drivers/i2c/busses/i2c-tegra.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * drivers/i2c/busses/i2c-tegra.c
   4  *
   5  * Copyright (C) 2010 Google, Inc.
   6  * Author: Colin Cross <[email protected]>
   7  */
   8
   9 #include <linux/bitfield.h>
  10 #include <linux/clk.h>
  11 #include <linux/delay.h>
  12 #include <linux/dmaengine.h>
  13 #include <linux/dma-mapping.h>
  14 #include <linux/err.h>
  15 #include <linux/i2c.h>
  16 #include <linux/init.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/io.h>
  19 #include <linux/iopoll.h>
  20 #include <linux/irq.h>
  21 #include <linux/kernel.h>
  22 #include <linux/ktime.h>
  23 #include <linux/module.h>
  24 #include <linux/of_device.h>
  25 #include <linux/pinctrl/consumer.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/pm_runtime.h>
  28 #include <linux/reset.h>
  29
  30 #define BYTES_PER_FIFO_WORD 4
  31
  32 #define I2C_CNFG                                0x000
  33 #define I2C_CNFG_DEBOUNCE_CNT                   GENMASK(14, 12)
  34 #define I2C_CNFG_PACKET_MODE_EN                 BIT(10)
  35 #define I2C_CNFG_NEW_MASTER_FSM                 BIT(11)
  36 #define I2C_CNFG_MULTI_MASTER_MODE              BIT(17)
  37 #define I2C_STATUS                              0x01c
  38 #define I2C_SL_CNFG                             0x020
  39 #define I2C_SL_CNFG_NACK                        BIT(1)
  40 #define I2C_SL_CNFG_NEWSL                       BIT(2)
  41 #define I2C_SL_ADDR1                            0x02c
  42 #define I2C_SL_ADDR2                            0x030
  43 #define I2C_TLOW_SEXT                           0x034
  44 #define I2C_TX_FIFO                             0x050
  45 #define I2C_RX_FIFO                             0x054
  46 #define I2C_PACKET_TRANSFER_STATUS              0x058
  47 #define I2C_FIFO_CONTROL                        0x05c
  48 #define I2C_FIFO_CONTROL_TX_FLUSH               BIT(1)
  49 #define I2C_FIFO_CONTROL_RX_FLUSH               BIT(0)
  50 #define I2C_FIFO_CONTROL_TX_TRIG(x)             (((x) - 1) << 5)
  51 #define I2C_FIFO_CONTROL_RX_TRIG(x)             (((x) - 1) << 2)
  52 #define I2C_FIFO_STATUS                         0x060
  53 #define I2C_FIFO_STATUS_TX                      GENMASK(7, 4)
  54 #define I2C_FIFO_STATUS_RX                      GENMASK(3, 0)
  55 #define I2C_INT_MASK                            0x064
  56 #define I2C_INT_STATUS                          0x068
  57 #define I2C_INT_BUS_CLR_DONE                    BIT(11)
  58 #define I2C_INT_PACKET_XFER_COMPLETE            BIT(7)
  59 #define I2C_INT_NO_ACK                          BIT(3)
  60 #define I2C_INT_ARBITRATION_LOST                BIT(2)
  61 #define I2C_INT_TX_FIFO_DATA_REQ                BIT(1)
  62 #define I2C_INT_RX_FIFO_DATA_REQ                BIT(0)
  63 #define I2C_CLK_DIVISOR                         0x06c
  64 #define I2C_CLK_DIVISOR_STD_FAST_MODE           GENMASK(31, 16)
  65 #define I2C_CLK_DIVISOR_HSMODE                  GENMASK(15, 0)
  66
  67 #define DVC_CTRL_REG1                           0x000
  68 #define DVC_CTRL_REG1_INTR_EN                   BIT(10)
  69 #define DVC_CTRL_REG3                           0x008
  70 #define DVC_CTRL_REG3_SW_PROG                   BIT(26)
  71 #define DVC_CTRL_REG3_I2C_DONE_INTR_EN          BIT(30)
  72 #define DVC_STATUS                              0x00c
  73 #define DVC_STATUS_I2C_DONE_INTR                BIT(30)
  74
  75 #define I2C_ERR_NONE                            0x00
  76 #define I2C_ERR_NO_ACK                          BIT(0)
  77 #define I2C_ERR_ARBITRATION_LOST                BIT(1)
  78 #define I2C_ERR_UNKNOWN_INTERRUPT               BIT(2)
  79 #define I2C_ERR_RX_BUFFER_OVERFLOW              BIT(3)
  80
  81 #define PACKET_HEADER0_HEADER_SIZE              GENMASK(29, 28)
  82 #define PACKET_HEADER0_PACKET_ID                GENMASK(23, 16)
  83 #define PACKET_HEADER0_CONT_ID                  GENMASK(15, 12)
  84 #define PACKET_HEADER0_PROTOCOL                 GENMASK(7, 4)
  85 #define PACKET_HEADER0_PROTOCOL_I2C             1
  86
  87 #define I2C_HEADER_CONT_ON_NAK                  BIT(21)
  88 #define I2C_HEADER_READ                         BIT(19)
  89 #define I2C_HEADER_10BIT_ADDR                   BIT(18)
  90 #define I2C_HEADER_IE_ENABLE                    BIT(17)
  91 #define I2C_HEADER_REPEAT_START                 BIT(16)
  92 #define I2C_HEADER_CONTINUE_XFER                BIT(15)
  93 #define I2C_HEADER_SLAVE_ADDR_SHIFT             1
  94
  95 #define I2C_BUS_CLEAR_CNFG                      0x084
  96 #define I2C_BC_SCLK_THRESHOLD                   GENMASK(23, 16)
  97 #define I2C_BC_STOP_COND                        BIT(2)
  98 #define I2C_BC_TERMINATE                        BIT(1)
  99 #define I2C_BC_ENABLE                           BIT(0)
 100 #define I2C_BUS_CLEAR_STATUS                    0x088
 101 #define I2C_BC_STATUS                           BIT(0)
 102
 103 #define I2C_CONFIG_LOAD                         0x08c
 104 #define I2C_MSTR_CONFIG_LOAD                    BIT(0)
 105
 106 #define I2C_CLKEN_OVERRIDE                      0x090
 107 #define I2C_MST_CORE_CLKEN_OVR                  BIT(0)
 108
 109 #define I2C_INTERFACE_TIMING_0                  0x094
 110 #define  I2C_INTERFACE_TIMING_THIGH             GENMASK(13, 8)
 111 #define  I2C_INTERFACE_TIMING_TLOW              GENMASK(5, 0)
 112 #define I2C_INTERFACE_TIMING_1                  0x098
 113 #define  I2C_INTERFACE_TIMING_TBUF              GENMASK(29, 24)
 114 #define  I2C_INTERFACE_TIMING_TSU_STO           GENMASK(21, 16)
 115 #define  I2C_INTERFACE_TIMING_THD_STA           GENMASK(13, 8)
 116 #define  I2C_INTERFACE_TIMING_TSU_STA           GENMASK(5, 0)
 117
 118 #define I2C_HS_INTERFACE_TIMING_0               0x09c
 119 #define  I2C_HS_INTERFACE_TIMING_THIGH          GENMASK(13, 8)
 120 #define  I2C_HS_INTERFACE_TIMING_TLOW           GENMASK(5, 0)
 121 #define I2C_HS_INTERFACE_TIMING_1               0x0a0
 122 #define  I2C_HS_INTERFACE_TIMING_TSU_STO        GENMASK(21, 16)
 123 #define  I2C_HS_INTERFACE_TIMING_THD_STA        GENMASK(13, 8)
 124 #define  I2C_HS_INTERFACE_TIMING_TSU_STA        GENMASK(5, 0)
 125
 126 #define I2C_MST_FIFO_CONTROL                    0x0b4
 127 #define I2C_MST_FIFO_CONTROL_RX_FLUSH           BIT(0)
 128 #define I2C_MST_FIFO_CONTROL_TX_FLUSH           BIT(1)
 129 #define I2C_MST_FIFO_CONTROL_RX_TRIG(x)         (((x) - 1) <<  4)
 130 #define I2C_MST_FIFO_CONTROL_TX_TRIG(x)         (((x) - 1) << 16)
 131
 132 #define I2C_MST_FIFO_STATUS                     0x0b8
 133 #define I2C_MST_FIFO_STATUS_TX                  GENMASK(23, 16)
 134 #define I2C_MST_FIFO_STATUS_RX                  GENMASK(7, 0)
 135
 136 /* configuration load timeout in microseconds */
 137 #define I2C_CONFIG_LOAD_TIMEOUT                 1000000
 138
 139 /* packet header size in bytes */
 140 #define I2C_PACKET_HEADER_SIZE                  12
 141
 142 /*
 143  * I2C Controller will use PIO mode for transfers up to 32 bytes in order to
 144  * avoid DMA overhead, otherwise external APB DMA controller will be used.
 145  * Note that the actual MAX PIO length is 20 bytes because 32 bytes include
 146  * I2C_PACKET_HEADER_SIZE.
 147  */
 148 #define I2C_PIO_MODE_PREFERRED_LEN              32
 149
 150 /*
 151  * msg_end_type: The bus control which needs to be sent at end of transfer.
 152  * @MSG_END_STOP: Send stop pulse.
 153  * @MSG_END_REPEAT_START: Send repeat-start.
 154  * @MSG_END_CONTINUE: Don't send stop or repeat-start.
 155  */
 156 enum msg_end_type {
 157         MSG_END_STOP,
 158         MSG_END_REPEAT_START,
 159         MSG_END_CONTINUE,
 160 };
 161
 162 /**
 163  * struct tegra_i2c_hw_feature : per hardware generation features
 164  * @has_continue_xfer_support: continue-transfer supported
 165  * @has_per_pkt_xfer_complete_irq: Has enable/disable capability for transfer
 166  *              completion interrupt on per packet basis.
 167  * @has_config_load_reg: Has the config load register to load the new
 168  *              configuration.
 169  * @clk_divisor_hs_mode: Clock divisor in HS mode.
 170  * @clk_divisor_std_mode: Clock divisor in standard mode. It is
 171  *              applicable if there is no fast clock source i.e. single clock
 172  *              source.
 173  * @clk_divisor_fast_mode: Clock divisor in fast mode. It is
 174  *              applicable if there is no fast clock source i.e. single clock
 175  *              source.
 176  * @clk_divisor_fast_plus_mode: Clock divisor in fast mode plus. It is
 177  *              applicable if there is no fast clock source (i.e. single
 178  *              clock source).
 179  * @has_multi_master_mode: The I2C controller supports running in single-master
 180  *              or multi-master mode.
 181  * @has_slcg_override_reg: The I2C controller supports a register that
 182  *              overrides the second level clock gating.
 183  * @has_mst_fifo: The I2C controller contains the new MST FIFO interface that
 184  *              provides additional features and allows for longer messages to
 185  *              be transferred in one go.
 186  * @quirks: I2C adapter quirks for limiting write/read transfer size and not
 187  *              allowing 0 length transfers.
 188  * @supports_bus_clear: Bus Clear support to recover from bus hang during
 189  *              SDA stuck low from device for some unknown reasons.
 190  * @has_apb_dma: Support of APBDMA on corresponding Tegra chip.
 191  * @tlow_std_mode: Low period of the clock in standard mode.
 192  * @thigh_std_mode: High period of the clock in standard mode.
 193  * @tlow_fast_fastplus_mode: Low period of the clock in fast/fast-plus modes.
 194  * @thigh_fast_fastplus_mode: High period of the clock in fast/fast-plus modes.
 195  * @setup_hold_time_std_mode: Setup and hold time for start and stop conditions
 196  *              in standard mode.
 197  * @setup_hold_time_fast_fast_plus_mode: Setup and hold time for start and stop
 198  *              conditions in fast/fast-plus modes.
 199  * @setup_hold_time_hs_mode: Setup and hold time for start and stop conditions
 200  *              in HS mode.
 201  * @has_interface_timing_reg: Has interface timing register to program the tuned
 202  *              timing settings.
 203  */
 204 struct tegra_i2c_hw_feature {
 205         bool has_continue_xfer_support;
 206         bool has_per_pkt_xfer_complete_irq;
 207         bool has_config_load_reg;
 208         u32 clk_divisor_hs_mode;
 209         u32 clk_divisor_std_mode;
 210         u32 clk_divisor_fast_mode;
 211         u32 clk_divisor_fast_plus_mode;
 212         bool has_multi_master_mode;
 213         bool has_slcg_override_reg;
 214         bool has_mst_fifo;
 215         const struct i2c_adapter_quirks *quirks;
 216         bool supports_bus_clear;
 217         bool has_apb_dma;
 218         u32 tlow_std_mode;
 219         u32 thigh_std_mode;
 220         u32 tlow_fast_fastplus_mode;
 221         u32 thigh_fast_fastplus_mode;
 222         u32 setup_hold_time_std_mode;
 223         u32 setup_hold_time_fast_fast_plus_mode;
 224         u32 setup_hold_time_hs_mode;
 225         bool has_interface_timing_reg;
 226 };
 227
 228 /**
 229  * struct tegra_i2c_dev - per device I2C context
 230  * @dev: device reference for power management
 231  * @hw: Tegra I2C HW feature
 232  * @adapter: core I2C layer adapter information
 233  * @div_clk: clock reference for div clock of I2C controller
 234  * @clocks: array of I2C controller clocks
 235  * @nclocks: number of clocks in the array
 236  * @rst: reset control for the I2C controller
 237  * @base: ioremapped registers cookie
 238  * @base_phys: physical base address of the I2C controller
 239  * @cont_id: I2C controller ID, used for packet header
 240  * @irq: IRQ number of transfer complete interrupt
 241  * @is_dvc: identifies the DVC I2C controller, has a different register layout
 242  * @is_vi: identifies the VI I2C controller, has a different register layout
 243  * @msg_complete: transfer completion notifier
 244  * @msg_err: error code for completed message
 245  * @msg_buf: pointer to current message data
 246  * @msg_buf_remaining: size of unsent data in the message buffer
 247  * @msg_read: indicates that the transfer is a read access
 248  * @bus_clk_rate: current I2C bus clock rate
 249  * @multimaster_mode: indicates that I2C controller is in multi-master mode
 250  * @tx_dma_chan: DMA transmit channel
 251  * @rx_dma_chan: DMA receive channel
 252  * @dma_phys: handle to DMA resources
 253  * @dma_buf: pointer to allocated DMA buffer
 254  * @dma_buf_size: DMA buffer size
 255  * @dma_mode: indicates active DMA transfer
 256  * @dma_complete: DMA completion notifier
 257  * @atomic_mode: indicates active atomic transfer
 258  */
 259 struct tegra_i2c_dev {
 260         struct device *dev;
 261         struct i2c_adapter adapter;
 262
 263         const struct tegra_i2c_hw_feature *hw;
 264         struct reset_control *rst;
 265         unsigned int cont_id;
 266         unsigned int irq;
 267
 268         phys_addr_t base_phys;
 269         void __iomem *base;
 270
 271         struct clk_bulk_data clocks[2];
 272         unsigned int nclocks;
 273
 274         struct clk *div_clk;
 275         u32 bus_clk_rate;
 276
 277         struct completion msg_complete;
 278         size_t msg_buf_remaining;
 279         int msg_err;
 280         u8 *msg_buf;
 281
 282         struct completion dma_complete;
 283         struct dma_chan *tx_dma_chan;
 284         struct dma_chan *rx_dma_chan;
 285         unsigned int dma_buf_size;
 286         dma_addr_t dma_phys;
 287         void *dma_buf;
 288
 289         bool multimaster_mode;
 290         bool atomic_mode;
 291         bool dma_mode;
 292         bool msg_read;
 293         bool is_dvc;
 294         bool is_vi;
 295 };
 296
 297 static void dvc_writel(struct tegra_i2c_dev *i2c_dev, u32 val,
 298                        unsigned int reg)
 299 {
 300         writel_relaxed(val, i2c_dev->base + reg);
 301 }
 302
 303 static u32 dvc_readl(struct tegra_i2c_dev *i2c_dev, unsigned int reg)
 304 {
 305         return readl_relaxed(i2c_dev->base + reg);
 306 }
 307
 308 /*
 309  * If necessary, i2c_writel() and i2c_readl() will offset the register
 310  * in order to talk to the I2C block inside the DVC block.
 311  */
 312 static u32 tegra_i2c_reg_addr(struct tegra_i2c_dev *i2c_dev, unsigned int reg)
 313 {
 314         if (i2c_dev->is_dvc)
 315                 reg += (reg >= I2C_TX_FIFO) ? 0x10 : 0x40;
 316         else if (i2c_dev->is_vi)
 317                 reg = 0xc00 + (reg << 2);
 318
 319         return reg;
 320 }
 321
 322 static void i2c_writel(struct tegra_i2c_dev *i2c_dev, u32 val, unsigned int reg)
 323 {
 324         writel_relaxed(val, i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
 325
 326         /* read back register to make sure that register writes completed */
 327         if (reg != I2C_TX_FIFO)
 328                 readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
 329         else if (i2c_dev->is_vi)
 330                 readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, I2C_INT_STATUS));
 331 }
 332
 333 static u32 i2c_readl(struct tegra_i2c_dev *i2c_dev, unsigned int reg)
 334 {
 335         return readl_relaxed(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg));
 336 }
 337
 338 static void i2c_writesl(struct tegra_i2c_dev *i2c_dev, void *data,
 339                         unsigned int reg, unsigned int len)
 340 {
 341         writesl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
 342 }
 343
 344 static void i2c_writesl_vi(struct tegra_i2c_dev *i2c_dev, void *data,
 345                            unsigned int reg, unsigned int len)
 346 {
 347         u32 *data32 = data;
 348
 349         /*
 350          * VI I2C controller has known hardware bug where writes get stuck
 351          * when immediate multiple writes happen to TX_FIFO register.
 352          * Recommended software work around is to read I2C register after
 353          * each write to TX_FIFO register to flush out the data.
 354          */
 355         while (len--)
 356                 i2c_writel(i2c_dev, *data32++, reg);
 357 }
 358
 359 static void i2c_readsl(struct tegra_i2c_dev *i2c_dev, void *data,
 360                        unsigned int reg, unsigned int len)
 361 {
 362         readsl(i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg), data, len);
 363 }
 364
 365 static void tegra_i2c_mask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask)
 366 {
 367         u32 int_mask;
 368
 369         int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) & ~mask;
 370         i2c_writel(i2c_dev, int_mask, I2C_INT_MASK);
 371 }
 372
 373 static void tegra_i2c_unmask_irq(struct tegra_i2c_dev *i2c_dev, u32 mask)
 374 {
 375         u32 int_mask;
 376
 377         int_mask = i2c_readl(i2c_dev, I2C_INT_MASK) | mask;
 378         i2c_writel(i2c_dev, int_mask, I2C_INT_MASK);
 379 }
 380
 381 static void tegra_i2c_dma_complete(void *args)
 382 {
 383         struct tegra_i2c_dev *i2c_dev = args;
 384
 385         complete(&i2c_dev->dma_complete);
 386 }
 387
 388 static int tegra_i2c_dma_submit(struct tegra_i2c_dev *i2c_dev, size_t len)
 389 {
 390         struct dma_async_tx_descriptor *dma_desc;
 391         enum dma_transfer_direction dir;
 392         struct dma_chan *chan;
 393
 394         dev_dbg(i2c_dev->dev, "starting DMA for length: %zu\n", len);
 395
 396         reinit_completion(&i2c_dev->dma_complete);
 397
 398         dir = i2c_dev->msg_read ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
 399         chan = i2c_dev->msg_read ? i2c_dev->rx_dma_chan : i2c_dev->tx_dma_chan;
 400
 401         dma_desc = dmaengine_prep_slave_single(chan, i2c_dev->dma_phys,
 402                                                len, dir, DMA_PREP_INTERRUPT |
 403                                                DMA_CTRL_ACK);
 404         if (!dma_desc) {
 405                 dev_err(i2c_dev->dev, "failed to get %s DMA descriptor\n",
 406                         i2c_dev->msg_read ? "RX" : "TX");
 407                 return -EINVAL;
 408         }
 409
 410         dma_desc->callback = tegra_i2c_dma_complete;
 411         dma_desc->callback_param = i2c_dev;
 412
 413         dmaengine_submit(dma_desc);
 414         dma_async_issue_pending(chan);
 415
 416         return 0;
 417 }
 418
 419 static void tegra_i2c_release_dma(struct tegra_i2c_dev *i2c_dev)
 420 {
 421         if (i2c_dev->dma_buf) {
 422                 dma_free_coherent(i2c_dev->dev, i2c_dev->dma_buf_size,
 423                                   i2c_dev->dma_buf, i2c_dev->dma_phys);
 424                 i2c_dev->dma_buf = NULL;
 425         }
 426
 427         if (i2c_dev->tx_dma_chan) {
 428                 dma_release_channel(i2c_dev->tx_dma_chan);
 429                 i2c_dev->tx_dma_chan = NULL;
 430         }
 431
 432         if (i2c_dev->rx_dma_chan) {
 433                 dma_release_channel(i2c_dev->rx_dma_chan);
 434                 i2c_dev->rx_dma_chan = NULL;
 435         }
 436 }
 437
 438 static int tegra_i2c_init_dma(struct tegra_i2c_dev *i2c_dev)
 439 {
 440         struct dma_chan *chan;
 441         dma_addr_t dma_phys;
 442         u32 *dma_buf;
 443         int err;
 444
 445         if (!i2c_dev->hw->has_apb_dma || i2c_dev->is_vi)
 446                 return 0;
 447
 448         if (!IS_ENABLED(CONFIG_TEGRA20_APB_DMA)) {
 449                 dev_dbg(i2c_dev->dev, "DMA support not enabled\n");
 450                 return 0;
 451         }
 452
 453         chan = dma_request_chan(i2c_dev->dev, "rx");
 454         if (IS_ERR(chan)) {
 455                 err = PTR_ERR(chan);
 456                 goto err_out;
 457         }
 458
 459         i2c_dev->rx_dma_chan = chan;
 460
 461         chan = dma_request_chan(i2c_dev->dev, "tx");
 462         if (IS_ERR(chan)) {
 463                 err = PTR_ERR(chan);
 464                 goto err_out;
 465         }
 466
 467         i2c_dev->tx_dma_chan = chan;
 468
 469         i2c_dev->dma_buf_size = i2c_dev->hw->quirks->max_write_len +
 470                                 I2C_PACKET_HEADER_SIZE;
 471
 472         dma_buf = dma_alloc_coherent(i2c_dev->dev, i2c_dev->dma_buf_size,
 473                                      &dma_phys, GFP_KERNEL | __GFP_NOWARN);
 474         if (!dma_buf) {
 475                 dev_err(i2c_dev->dev, "failed to allocate DMA buffer\n");
 476                 err = -ENOMEM;
 477                 goto err_out;
 478         }
 479
 480         i2c_dev->dma_buf = dma_buf;
 481         i2c_dev->dma_phys = dma_phys;
 482
 483         return 0;
 484
 485 err_out:
 486         tegra_i2c_release_dma(i2c_dev);
 487         if (err != -EPROBE_DEFER) {
 488                 dev_err(i2c_dev->dev, "cannot use DMA: %d\n", err);
 489                 dev_err(i2c_dev->dev, "falling back to PIO\n");
 490                 return 0;
 491         }
 492
 493         return err;
 494 }
 495
 496 /*
 497  * One of the Tegra I2C blocks is inside the DVC (Digital Voltage Controller)
 498  * block.  This block is identical to the rest of the I2C blocks, except that
 499  * it only supports master mode, it has registers moved around, and it needs
 500  * some extra init to get it into I2C mode.  The register moves are handled
 501  * by i2c_readl() and i2c_writel().
 502  */
 503 static void tegra_dvc_init(struct tegra_i2c_dev *i2c_dev)
 504 {
 505         u32 val;
 506
 507         val = dvc_readl(i2c_dev, DVC_CTRL_REG3);
 508         val |= DVC_CTRL_REG3_SW_PROG;
 509         val |= DVC_CTRL_REG3_I2C_DONE_INTR_EN;
 510         dvc_writel(i2c_dev, val, DVC_CTRL_REG3);
 511
 512         val = dvc_readl(i2c_dev, DVC_CTRL_REG1);
 513         val |= DVC_CTRL_REG1_INTR_EN;
 514         dvc_writel(i2c_dev, val, DVC_CTRL_REG1);
 515 }
 516
 517 static void tegra_i2c_vi_init(struct tegra_i2c_dev *i2c_dev)
 518 {
 519         u32 value;
 520
 521         value = FIELD_PREP(I2C_INTERFACE_TIMING_THIGH, 2) |
 522                 FIELD_PREP(I2C_INTERFACE_TIMING_TLOW, 4);
 523         i2c_writel(i2c_dev, value, I2C_INTERFACE_TIMING_0);
 524
 525         value = FIELD_PREP(I2C_INTERFACE_TIMING_TBUF, 4) |
 526                 FIELD_PREP(I2C_INTERFACE_TIMING_TSU_STO, 7) |
 527                 FIELD_PREP(I2C_INTERFACE_TIMING_THD_STA, 4) |
 528                 FIELD_PREP(I2C_INTERFACE_TIMING_TSU_STA, 4);
 529         i2c_writel(i2c_dev, value, I2C_INTERFACE_TIMING_1);
 530
 531         value = FIELD_PREP(I2C_HS_INTERFACE_TIMING_THIGH, 3) |
 532                 FIELD_PREP(I2C_HS_INTERFACE_TIMING_TLOW, 8);
 533         i2c_writel(i2c_dev, value, I2C_HS_INTERFACE_TIMING_0);
 534
 535         value = FIELD_PREP(I2C_HS_INTERFACE_TIMING_TSU_STO, 11) |
 536                 FIELD_PREP(I2C_HS_INTERFACE_TIMING_THD_STA, 11) |
 537                 FIELD_PREP(I2C_HS_INTERFACE_TIMING_TSU_STA, 11);
 538         i2c_writel(i2c_dev, value, I2C_HS_INTERFACE_TIMING_1);
 539
 540         value = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND;
 541         i2c_writel(i2c_dev, value, I2C_BUS_CLEAR_CNFG);
 542
 543         i2c_writel(i2c_dev, 0x0, I2C_TLOW_SEXT);
 544 }
 545
 546 static int tegra_i2c_poll_register(struct tegra_i2c_dev *i2c_dev,
 547                                    u32 reg, u32 mask, u32 delay_us,
 548                                    u32 timeout_us)
 549 {
 550         void __iomem *addr = i2c_dev->base + tegra_i2c_reg_addr(i2c_dev, reg);
 551         u32 val;
 552
 553         if (!i2c_dev->atomic_mode)
 554                 return readl_relaxed_poll_timeout(addr, val, !(val & mask),
 555                                                   delay_us, timeout_us);
 556
 557         return readl_relaxed_poll_timeout_atomic(addr, val, !(val & mask),
 558                                                  delay_us, timeout_us);
 559 }
 560
 561 static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev)
 562 {
 563         u32 mask, val, offset;
 564         int err;
 565
 566         if (i2c_dev->hw->has_mst_fifo) {
 567                 mask = I2C_MST_FIFO_CONTROL_TX_FLUSH |
 568                        I2C_MST_FIFO_CONTROL_RX_FLUSH;
 569                 offset = I2C_MST_FIFO_CONTROL;
 570         } else {
 571                 mask = I2C_FIFO_CONTROL_TX_FLUSH |
 572                        I2C_FIFO_CONTROL_RX_FLUSH;
 573                 offset = I2C_FIFO_CONTROL;
 574         }
 575
 576         val = i2c_readl(i2c_dev, offset);
 577         val |= mask;
 578         i2c_writel(i2c_dev, val, offset);
 579
 580         err = tegra_i2c_poll_register(i2c_dev, offset, mask, 1000, 1000000);
 581         if (err) {
 582                 dev_err(i2c_dev->dev, "failed to flush FIFO\n");
 583                 return err;
 584         }
 585
 586         return 0;
 587 }
 588
 589 static int tegra_i2c_wait_for_config_load(struct tegra_i2c_dev *i2c_dev)
 590 {
 591         int err;
 592
 593         if (!i2c_dev->hw->has_config_load_reg)
 594                 return 0;
 595
 596         i2c_writel(i2c_dev, I2C_MSTR_CONFIG_LOAD, I2C_CONFIG_LOAD);
 597
 598         err = tegra_i2c_poll_register(i2c_dev, I2C_CONFIG_LOAD, 0xffffffff,
 599                                       1000, I2C_CONFIG_LOAD_TIMEOUT);
 600         if (err) {
 601                 dev_err(i2c_dev->dev, "failed to load config\n");
 602                 return err;
 603         }
 604
 605         return 0;
 606 }
 607
 608 static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
 609 {
 610         u32 val, clk_divisor, clk_multiplier, tsu_thd, tlow, thigh, non_hs_mode;
 611         int err;
 612
 613         /*
 614          * The reset shouldn't ever fail in practice. The failure will be a
 615          * sign of a severe problem that needs to be resolved. Still we don't
 616          * want to fail the initialization completely because this may break
 617          * kernel boot up since voltage regulators use I2C. Hence, we will
 618          * emit a noisy warning on error, which won't stay unnoticed and
 619          * won't hose machine entirely.
 620          */
 621         err = reset_control_reset(i2c_dev->rst);
 622         WARN_ON_ONCE(err);
 623
 624         if (i2c_dev->is_dvc)
 625                 tegra_dvc_init(i2c_dev);
 626
 627         val = I2C_CNFG_NEW_MASTER_FSM | I2C_CNFG_PACKET_MODE_EN |
 628               FIELD_PREP(I2C_CNFG_DEBOUNCE_CNT, 2);
 629
 630         if (i2c_dev->hw->has_multi_master_mode)
 631                 val |= I2C_CNFG_MULTI_MASTER_MODE;
 632
 633         i2c_writel(i2c_dev, val, I2C_CNFG);
 634         i2c_writel(i2c_dev, 0, I2C_INT_MASK);
 635
 636         if (i2c_dev->is_vi)
 637                 tegra_i2c_vi_init(i2c_dev);
 638
 639         switch (i2c_dev->bus_clk_rate) {
 640         case I2C_MAX_STANDARD_MODE_FREQ + 1 ... I2C_MAX_FAST_MODE_PLUS_FREQ:
 641         default:
 642                 tlow = i2c_dev->hw->tlow_fast_fastplus_mode;
 643                 thigh = i2c_dev->hw->thigh_fast_fastplus_mode;
 644                 tsu_thd = i2c_dev->hw->setup_hold_time_fast_fast_plus_mode;
 645
 646                 if (i2c_dev->bus_clk_rate > I2C_MAX_FAST_MODE_FREQ)
 647                         non_hs_mode = i2c_dev->hw->clk_divisor_fast_plus_mode;
 648                 else
 649                         non_hs_mode = i2c_dev->hw->clk_divisor_fast_mode;
 650                 break;
 651
 652         case 0 ... I2C_MAX_STANDARD_MODE_FREQ:
 653                 tlow = i2c_dev->hw->tlow_std_mode;
 654                 thigh = i2c_dev->hw->thigh_std_mode;
 655                 tsu_thd = i2c_dev->hw->setup_hold_time_std_mode;
 656                 non_hs_mode = i2c_dev->hw->clk_divisor_std_mode;
 657                 break;
 658         }
 659
 660         /* make sure clock divisor programmed correctly */
 661         clk_divisor = FIELD_PREP(I2C_CLK_DIVISOR_HSMODE,
 662                                  i2c_dev->hw->clk_divisor_hs_mode) |
 663                       FIELD_PREP(I2C_CLK_DIVISOR_STD_FAST_MODE, non_hs_mode);
 664         i2c_writel(i2c_dev, clk_divisor, I2C_CLK_DIVISOR);
 665
 666         if (i2c_dev->hw->has_interface_timing_reg) {
 667                 val = FIELD_PREP(I2C_INTERFACE_TIMING_THIGH, thigh) |
 668                       FIELD_PREP(I2C_INTERFACE_TIMING_TLOW, tlow);
 669                 i2c_writel(i2c_dev, val, I2C_INTERFACE_TIMING_0);
 670         }
 671
 672         /*
 673          * Configure setup and hold times only when tsu_thd is non-zero.
 674          * Otherwise, preserve the chip default values.
 675          */
 676         if (i2c_dev->hw->has_interface_timing_reg && tsu_thd)
 677                 i2c_writel(i2c_dev, tsu_thd, I2C_INTERFACE_TIMING_1);
 678
 679         clk_multiplier = (tlow + thigh + 2) * (non_hs_mode + 1);
 680
 681         err = clk_set_rate(i2c_dev->div_clk,
 682                            i2c_dev->bus_clk_rate * clk_multiplier);
 683         if (err) {
 684                 dev_err(i2c_dev->dev, "failed to set div-clk rate: %d\n", err);
 685                 return err;
 686         }
 687
 688         if (!i2c_dev->is_dvc && !i2c_dev->is_vi) {
 689                 u32 sl_cfg = i2c_readl(i2c_dev, I2C_SL_CNFG);
 690
 691                 sl_cfg |= I2C_SL_CNFG_NACK | I2C_SL_CNFG_NEWSL;
 692                 i2c_writel(i2c_dev, sl_cfg, I2C_SL_CNFG);
 693                 i2c_writel(i2c_dev, 0xfc, I2C_SL_ADDR1);
 694                 i2c_writel(i2c_dev, 0x00, I2C_SL_ADDR2);
 695         }
 696
 697         err = tegra_i2c_flush_fifos(i2c_dev);
 698         if (err)
 699                 return err;
 700
 701         if (i2c_dev->multimaster_mode && i2c_dev->hw->has_slcg_override_reg)
 702                 i2c_writel(i2c_dev, I2C_MST_CORE_CLKEN_OVR, I2C_CLKEN_OVERRIDE);
 703
 704         err = tegra_i2c_wait_for_config_load(i2c_dev);
 705         if (err)
 706                 return err;
 707
 708         return 0;
 709 }
 710
 711 static int tegra_i2c_disable_packet_mode(struct tegra_i2c_dev *i2c_dev)
 712 {
 713         u32 cnfg;
 714
 715         /*
 716          * NACK interrupt is generated before the I2C controller generates
 717          * the STOP condition on the bus.  So, wait for 2 clock periods
 718          * before disabling the controller so that the STOP condition has
 719          * been delivered properly.
 720          */
 721         udelay(DIV_ROUND_UP(2 * 1000000, i2c_dev->bus_clk_rate));
 722
 723         cnfg = i2c_readl(i2c_dev, I2C_CNFG);
 724         if (cnfg & I2C_CNFG_PACKET_MODE_EN)
 725                 i2c_writel(i2c_dev, cnfg & ~I2C_CNFG_PACKET_MODE_EN, I2C_CNFG);
 726
 727         return tegra_i2c_wait_for_config_load(i2c_dev);
 728 }
 729
 730 static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
 731 {
 732         size_t buf_remaining = i2c_dev->msg_buf_remaining;
 733         unsigned int words_to_transfer, rx_fifo_avail;
 734         u8 *buf = i2c_dev->msg_buf;
 735         u32 val;
 736
 737         /*
 738          * Catch overflow due to message fully sent before the check for
 739          * RX FIFO availability.
 740          */
 741         if (WARN_ON_ONCE(!(i2c_dev->msg_buf_remaining)))
 742                 return -EINVAL;
 743
 744         if (i2c_dev->hw->has_mst_fifo) {
 745                 val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS);
 746                 rx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_RX, val);
 747         } else {
 748                 val = i2c_readl(i2c_dev, I2C_FIFO_STATUS);
 749                 rx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_RX, val);
 750         }
 751
 752         /* round down to exclude partial word at the end of buffer */
 753         words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD;
 754         if (words_to_transfer > rx_fifo_avail)
 755                 words_to_transfer = rx_fifo_avail;
 756
 757         i2c_readsl(i2c_dev, buf, I2C_RX_FIFO, words_to_transfer);
 758
 759         buf += words_to_transfer * BYTES_PER_FIFO_WORD;
 760         buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
 761         rx_fifo_avail -= words_to_transfer;
 762
 763         /*
 764          * If there is a partial word at the end of buffer, handle it
 765          * manually to prevent overwriting past the end of buffer.
 766          */
 767         if (rx_fifo_avail > 0 && buf_remaining > 0) {
 768                 /*
 769                  * buf_remaining > 3 check not needed as rx_fifo_avail == 0
 770                  * when (words_to_transfer was > rx_fifo_avail) earlier
 771                  * in this function.
 772                  */
 773                 val = i2c_readl(i2c_dev, I2C_RX_FIFO);
 774                 val = cpu_to_le32(val);
 775                 memcpy(buf, &val, buf_remaining);
 776                 buf_remaining = 0;
 777                 rx_fifo_avail--;
 778         }
 779
 780         /* RX FIFO must be drained, otherwise it's an Overflow case. */
 781         if (WARN_ON_ONCE(rx_fifo_avail))
 782                 return -EINVAL;
 783
 784         i2c_dev->msg_buf_remaining = buf_remaining;
 785         i2c_dev->msg_buf = buf;
 786
 787         return 0;
 788 }
 789
 790 static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
 791 {
 792         size_t buf_remaining = i2c_dev->msg_buf_remaining;
 793         unsigned int words_to_transfer, tx_fifo_avail;
 794         u8 *buf = i2c_dev->msg_buf;
 795         u32 val;
 796
 797         if (i2c_dev->hw->has_mst_fifo) {
 798                 val = i2c_readl(i2c_dev, I2C_MST_FIFO_STATUS);
 799                 tx_fifo_avail = FIELD_GET(I2C_MST_FIFO_STATUS_TX, val);
 800         } else {
 801                 val = i2c_readl(i2c_dev, I2C_FIFO_STATUS);
 802                 tx_fifo_avail = FIELD_GET(I2C_FIFO_STATUS_TX, val);
 803         }
 804
 805         /* round down to exclude partial word at the end of buffer */
 806         words_to_transfer = buf_remaining / BYTES_PER_FIFO_WORD;
 807
 808         /*
 809          * This hunk pushes 4 bytes at a time into the TX FIFO.
 810          *
 811          * It's very common to have < 4 bytes, hence there is no word
 812          * to push if we have less than 4 bytes to transfer.
 813          */
 814         if (words_to_transfer) {
 815                 if (words_to_transfer > tx_fifo_avail)
 816                         words_to_transfer = tx_fifo_avail;
 817
 818                 /*
 819                  * Update state before writing to FIFO.  Note that this may
 820                  * cause us to finish writing all bytes (AKA buf_remaining
 821                  * goes to 0), hence we have a potential for an interrupt
 822                  * (PACKET_XFER_COMPLETE is not maskable), but GIC interrupt
 823                  * is disabled at this point.
 824                  */
 825                 buf_remaining -= words_to_transfer * BYTES_PER_FIFO_WORD;
 826                 tx_fifo_avail -= words_to_transfer;
 827
 828                 i2c_dev->msg_buf_remaining = buf_remaining;
 829                 i2c_dev->msg_buf = buf + words_to_transfer * BYTES_PER_FIFO_WORD;
 830
 831                 if (i2c_dev->is_vi)
 832                         i2c_writesl_vi(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer);
 833                 else
 834                         i2c_writesl(i2c_dev, buf, I2C_TX_FIFO, words_to_transfer);
 835
 836                 buf += words_to_transfer * BYTES_PER_FIFO_WORD;
 837         }
 838
 839         /*
 840          * If there is a partial word at the end of buffer, handle it manually
 841          * to prevent reading past the end of buffer, which could cross a page
 842          * boundary and fault.
 843          */
 844         if (tx_fifo_avail > 0 && buf_remaining > 0) {
 845                 /*
 846                  * buf_remaining > 3 check not needed as tx_fifo_avail == 0
 847                  * when (words_to_transfer was > tx_fifo_avail) earlier
 848                  * in this function for non-zero words_to_transfer.
 849                  */
 850                 memcpy(&val, buf, buf_remaining);
 851                 val = le32_to_cpu(val);
 852
 853                 i2c_dev->msg_buf_remaining = 0;
 854                 i2c_dev->msg_buf = NULL;
 855
 856                 i2c_writel(i2c_dev, val, I2C_TX_FIFO);
 857         }
 858
 859         return 0;
 860 }
 861
 862 static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
 863 {
 864         const u32 status_err = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
 865         struct tegra_i2c_dev *i2c_dev = dev_id;
 866         u32 status;
 867
 868         status = i2c_readl(i2c_dev, I2C_INT_STATUS);
 869
 870         if (status == 0) {
 871                 dev_warn(i2c_dev->dev, "IRQ status 0 %08x %08x %08x\n",
 872                          i2c_readl(i2c_dev, I2C_PACKET_TRANSFER_STATUS),
 873                          i2c_readl(i2c_dev, I2C_STATUS),
 874                          i2c_readl(i2c_dev, I2C_CNFG));
 875                 i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT;
 876                 goto err;
 877         }
 878
 879         if (status & status_err) {
 880                 tegra_i2c_disable_packet_mode(i2c_dev);
 881                 if (status & I2C_INT_NO_ACK)
 882                         i2c_dev->msg_err |= I2C_ERR_NO_ACK;
 883                 if (status & I2C_INT_ARBITRATION_LOST)
 884                         i2c_dev->msg_err |= I2C_ERR_ARBITRATION_LOST;
 885                 goto err;
 886         }
 887
 888         /*
 889          * I2C transfer is terminated during the bus clear, so skip
 890          * processing the other interrupts.
 891          */
 892         if (i2c_dev->hw->supports_bus_clear && (status & I2C_INT_BUS_CLR_DONE))
 893                 goto err;
 894
 895         if (!i2c_dev->dma_mode) {
 896                 if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
 897                         if (tegra_i2c_empty_rx_fifo(i2c_dev)) {
 898                                 /*
 899                                  * Overflow error condition: message fully sent,
 900                                  * with no XFER_COMPLETE interrupt but hardware
 901                                  * asks to transfer more.
 902                                  */
 903                                 i2c_dev->msg_err |= I2C_ERR_RX_BUFFER_OVERFLOW;
 904                                 goto err;
 905                         }
 906                 }
 907
 908                 if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
 909                         if (i2c_dev->msg_buf_remaining)
 910                                 tegra_i2c_fill_tx_fifo(i2c_dev);
 911                         else
 912                                 tegra_i2c_mask_irq(i2c_dev,
 913                                                    I2C_INT_TX_FIFO_DATA_REQ);
 914                 }
 915         }
 916
 917         i2c_writel(i2c_dev, status, I2C_INT_STATUS);
 918         if (i2c_dev->is_dvc)
 919                 dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
 920
 921         /*
 922          * During message read XFER_COMPLETE interrupt is triggered prior to
 923          * DMA completion and during message write XFER_COMPLETE interrupt is
 924          * triggered after DMA completion.
 925          *
 926          * PACKETS_XFER_COMPLETE indicates completion of all bytes of transfer,
 927          * so forcing msg_buf_remaining to 0 in DMA mode.
 928          */
 929         if (status & I2C_INT_PACKET_XFER_COMPLETE) {
 930                 if (i2c_dev->dma_mode)
 931                         i2c_dev->msg_buf_remaining = 0;
 932                 /*
 933                  * Underflow error condition: XFER_COMPLETE before message
 934                  * fully sent.
 935                  */
 936                 if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining)) {
 937                         i2c_dev->msg_err |= I2C_ERR_UNKNOWN_INTERRUPT;
 938                         goto err;
 939                 }
 940                 complete(&i2c_dev->msg_complete);
 941         }
 942         goto done;
 943 err:
 944         /* mask all interrupts on error */
 945         tegra_i2c_mask_irq(i2c_dev,
 946                            I2C_INT_NO_ACK |
 947                            I2C_INT_ARBITRATION_LOST |
 948                            I2C_INT_PACKET_XFER_COMPLETE |
 949                            I2C_INT_TX_FIFO_DATA_REQ |
 950                            I2C_INT_RX_FIFO_DATA_REQ);
 951
 952         if (i2c_dev->hw->supports_bus_clear)
 953                 tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE);
 954
 955         i2c_writel(i2c_dev, status, I2C_INT_STATUS);
 956
 957         if (i2c_dev->is_dvc)
 958                 dvc_writel(i2c_dev, DVC_STATUS_I2C_DONE_INTR, DVC_STATUS);
 959
 960         if (i2c_dev->dma_mode) {
 961                 if (i2c_dev->msg_read)
 962                         dmaengine_terminate_async(i2c_dev->rx_dma_chan);
 963                 else
 964                         dmaengine_terminate_async(i2c_dev->tx_dma_chan);
 965
 966                 complete(&i2c_dev->dma_complete);
 967         }
 968
 969         complete(&i2c_dev->msg_complete);
 970 done:
 971         return IRQ_HANDLED;
 972 }
 973
 974 static void tegra_i2c_config_fifo_trig(struct tegra_i2c_dev *i2c_dev,
 975                                        size_t len)
 976 {
 977         struct dma_slave_config slv_config = {0};
 978         u32 val, reg, dma_burst, reg_offset;
 979         struct dma_chan *chan;
 980         int err;
 981
 982         if (i2c_dev->hw->has_mst_fifo)
 983                 reg = I2C_MST_FIFO_CONTROL;
 984         else
 985                 reg = I2C_FIFO_CONTROL;
 986
 987         if (i2c_dev->dma_mode) {
 988                 if (len & 0xF)
 989                         dma_burst = 1;
 990                 else if (len & 0x10)
 991                         dma_burst = 4;
 992                 else
 993                         dma_burst = 8;
 994
 995                 if (i2c_dev->msg_read) {
 996                         chan = i2c_dev->rx_dma_chan;
 997                         reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_RX_FIFO);
 998
 999                         slv_config.src_addr = i2c_dev->base_phys + reg_offset;
1000                         slv_config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1001                         slv_config.src_maxburst = dma_burst;
1002
1003                         if (i2c_dev->hw->has_mst_fifo)
1004                                 val = I2C_MST_FIFO_CONTROL_RX_TRIG(dma_burst);
1005                         else
1006                                 val = I2C_FIFO_CONTROL_RX_TRIG(dma_burst);
1007                 } else {
1008                         chan = i2c_dev->tx_dma_chan;
1009                         reg_offset = tegra_i2c_reg_addr(i2c_dev, I2C_TX_FIFO);
1010
1011                         slv_config.dst_addr = i2c_dev->base_phys + reg_offset;
1012                         slv_config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1013                         slv_config.dst_maxburst = dma_burst;
1014
1015                         if (i2c_dev->hw->has_mst_fifo)
1016                                 val = I2C_MST_FIFO_CONTROL_TX_TRIG(dma_burst);
1017                         else
1018                                 val = I2C_FIFO_CONTROL_TX_TRIG(dma_burst);
1019                 }
1020
1021                 slv_config.device_fc = true;
1022                 err = dmaengine_slave_config(chan, &slv_config);
1023                 if (err) {
1024                         dev_err(i2c_dev->dev, "DMA config failed: %d\n", err);
1025                         dev_err(i2c_dev->dev, "falling back to PIO\n");
1026
1027                         tegra_i2c_release_dma(i2c_dev);
1028                         i2c_dev->dma_mode = false;
1029                 } else {
1030                         goto out;
1031                 }
1032         }
1033
1034         if (i2c_dev->hw->has_mst_fifo)
1035                 val = I2C_MST_FIFO_CONTROL_TX_TRIG(8) |
1036                       I2C_MST_FIFO_CONTROL_RX_TRIG(1);
1037         else
1038                 val = I2C_FIFO_CONTROL_TX_TRIG(8) |
1039                       I2C_FIFO_CONTROL_RX_TRIG(1);
1040 out:
1041         i2c_writel(i2c_dev, val, reg);
1042 }
1043
1044 static unsigned long tegra_i2c_poll_completion(struct tegra_i2c_dev *i2c_dev,
1045                                                struct completion *complete,
1046                                                unsigned int timeout_ms)
1047 {
1048         ktime_t ktime = ktime_get();
1049         ktime_t ktimeout = ktime_add_ms(ktime, timeout_ms);
1050
1051         do {
1052                 u32 status = i2c_readl(i2c_dev, I2C_INT_STATUS);
1053
1054                 if (status)
1055                         tegra_i2c_isr(i2c_dev->irq, i2c_dev);
1056
1057                 if (completion_done(complete)) {
1058                         s64 delta = ktime_ms_delta(ktimeout, ktime);
1059
1060                         return msecs_to_jiffies(delta) ?: 1;
1061                 }
1062
1063                 ktime = ktime_get();
1064
1065         } while (ktime_before(ktime, ktimeout));
1066
1067         return 0;
1068 }
1069
1070 static unsigned long tegra_i2c_wait_completion(struct tegra_i2c_dev *i2c_dev,
1071                                                struct completion *complete,
1072                                                unsigned int timeout_ms)
1073 {
1074         unsigned long ret;
1075
1076         if (i2c_dev->atomic_mode) {
1077                 ret = tegra_i2c_poll_completion(i2c_dev, complete, timeout_ms);
1078         } else {
1079                 enable_irq(i2c_dev->irq);
1080                 ret = wait_for_completion_timeout(complete,
1081                                                   msecs_to_jiffies(timeout_ms));
1082                 disable_irq(i2c_dev->irq);
1083
1084                 /*
1085                  * Under some rare circumstances (like running KASAN +
1086                  * NFS root) CPU, which handles interrupt, may stuck in
1087                  * uninterruptible state for a significant time.  In this
1088                  * case we will get timeout if I2C transfer is running on
1089                  * a sibling CPU, despite of IRQ being raised.
1090                  *
1091                  * In order to handle this rare condition, the IRQ status
1092                  * needs to be checked after timeout.
1093                  */
1094                 if (ret == 0)
1095                         ret = tegra_i2c_poll_completion(i2c_dev, complete, 0);
1096         }
1097
1098         return ret;
1099 }
1100
1101 static int tegra_i2c_issue_bus_clear(struct i2c_adapter *adap)
1102 {
1103         struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
1104         u32 val, time_left;
1105         int err;
1106
1107         reinit_completion(&i2c_dev->msg_complete);
1108
1109         val = FIELD_PREP(I2C_BC_SCLK_THRESHOLD, 9) | I2C_BC_STOP_COND |
1110               I2C_BC_TERMINATE;
1111         i2c_writel(i2c_dev, val, I2C_BUS_CLEAR_CNFG);
1112
1113         err = tegra_i2c_wait_for_config_load(i2c_dev);
1114         if (err)
1115                 return err;
1116
1117         val |= I2C_BC_ENABLE;
1118         i2c_writel(i2c_dev, val, I2C_BUS_CLEAR_CNFG);
1119         tegra_i2c_unmask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE);
1120
1121         time_left = tegra_i2c_wait_completion(i2c_dev, &i2c_dev->msg_complete, 50);
1122         tegra_i2c_mask_irq(i2c_dev, I2C_INT_BUS_CLR_DONE);
1123
1124         if (time_left == 0) {
1125                 dev_err(i2c_dev->dev, "failed to clear bus\n");
1126                 return -ETIMEDOUT;
1127         }
1128
1129         val = i2c_readl(i2c_dev, I2C_BUS_CLEAR_STATUS);
1130         if (!(val & I2C_BC_STATUS)) {
1131                 dev_err(i2c_dev->dev, "un-recovered arbitration lost\n");
1132                 return -EIO;
1133         }
1134
1135         return -EAGAIN;
1136 }
1137
1138 static void tegra_i2c_push_packet_header(struct tegra_i2c_dev *i2c_dev,
1139                                          struct i2c_msg *msg,
1140                                          enum msg_end_type end_state)
1141 {
1142         u32 *dma_buf = i2c_dev->dma_buf;
1143         u32 packet_header;
1144
1145         packet_header = FIELD_PREP(PACKET_HEADER0_HEADER_SIZE, 0) |
1146                         FIELD_PREP(PACKET_HEADER0_PROTOCOL,
1147                                    PACKET_HEADER0_PROTOCOL_I2C) |
1148                         FIELD_PREP(PACKET_HEADER0_CONT_ID, i2c_dev->cont_id) |
1149                         FIELD_PREP(PACKET_HEADER0_PACKET_ID, 1);
1150
1151         if (i2c_dev->dma_mode && !i2c_dev->msg_read)
1152                 *dma_buf++ = packet_header;
1153         else
1154                 i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
1155
1156         packet_header = msg->len - 1;
1157
1158         if (i2c_dev->dma_mode && !i2c_dev->msg_read)
1159                 *dma_buf++ = packet_header;
1160         else
1161                 i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
1162
1163         packet_header = I2C_HEADER_IE_ENABLE;
1164
1165         if (end_state == MSG_END_CONTINUE)
1166                 packet_header |= I2C_HEADER_CONTINUE_XFER;
1167         else if (end_state == MSG_END_REPEAT_START)
1168                 packet_header |= I2C_HEADER_REPEAT_START;
1169
1170         if (msg->flags & I2C_M_TEN) {
1171                 packet_header |= msg->addr;
1172                 packet_header |= I2C_HEADER_10BIT_ADDR;
1173         } else {
1174                 packet_header |= msg->addr << I2C_HEADER_SLAVE_ADDR_SHIFT;
1175         }
1176
1177         if (msg->flags & I2C_M_IGNORE_NAK)
1178                 packet_header |= I2C_HEADER_CONT_ON_NAK;
1179
1180         if (msg->flags & I2C_M_RD)
1181                 packet_header |= I2C_HEADER_READ;
1182
1183         if (i2c_dev->dma_mode && !i2c_dev->msg_read)
1184                 *dma_buf++ = packet_header;
1185         else
1186                 i2c_writel(i2c_dev, packet_header, I2C_TX_FIFO);
1187 }
1188
1189 static int tegra_i2c_error_recover(struct tegra_i2c_dev *i2c_dev,
1190                                    struct i2c_msg *msg)
1191 {
1192         if (i2c_dev->msg_err == I2C_ERR_NONE)
1193                 return 0;
1194
1195         tegra_i2c_init(i2c_dev);
1196
1197         /* start recovery upon arbitration loss in single master mode */
1198         if (i2c_dev->msg_err == I2C_ERR_ARBITRATION_LOST) {
1199                 if (!i2c_dev->multimaster_mode)
1200                         return i2c_recover_bus(&i2c_dev->adapter);
1201
1202                 return -EAGAIN;
1203         }
1204
1205         if (i2c_dev->msg_err == I2C_ERR_NO_ACK) {
1206                 if (msg->flags & I2C_M_IGNORE_NAK)
1207                         return 0;
1208
1209                 return -EREMOTEIO;
1210         }
1211
1212         return -EIO;
1213 }
1214
1215 static int tegra_i2c_xfer_msg(struct tegra_i2c_dev *i2c_dev,
1216                               struct i2c_msg *msg,
1217                               enum msg_end_type end_state)
1218 {
1219         unsigned long time_left, xfer_time = 100;
1220         size_t xfer_size;
1221         u32 int_mask;
1222         int err;
1223
1224         err = tegra_i2c_flush_fifos(i2c_dev);
1225         if (err)
1226                 return err;
1227
1228         i2c_dev->msg_buf = msg->buf;
1229         i2c_dev->msg_buf_remaining = msg->len;
1230         i2c_dev->msg_err = I2C_ERR_NONE;
1231         i2c_dev->msg_read = !!(msg->flags & I2C_M_RD);
1232         reinit_completion(&i2c_dev->msg_complete);
1233
1234         if (i2c_dev->msg_read)
1235                 xfer_size = msg->len;
1236         else
1237                 xfer_size = msg->len + I2C_PACKET_HEADER_SIZE;
1238
1239         xfer_size = ALIGN(xfer_size, BYTES_PER_FIFO_WORD);
1240
1241         i2c_dev->dma_mode = xfer_size > I2C_PIO_MODE_PREFERRED_LEN &&
1242                             i2c_dev->dma_buf && !i2c_dev->atomic_mode;
1243
1244         tegra_i2c_config_fifo_trig(i2c_dev, xfer_size);
1245
1246         /*
1247          * Transfer time in mSec = Total bits / transfer rate
1248          * Total bits = 9 bits per byte (including ACK bit) + Start & stop bits
1249          */
1250         xfer_time += DIV_ROUND_CLOSEST(((xfer_size * 9) + 2) * MSEC_PER_SEC,
1251                                        i2c_dev->bus_clk_rate);
1252
1253         int_mask = I2C_INT_NO_ACK | I2C_INT_ARBITRATION_LOST;
1254         tegra_i2c_unmask_irq(i2c_dev, int_mask);
1255
1256         if (i2c_dev->dma_mode) {
1257                 if (i2c_dev->msg_read) {
1258                         dma_sync_single_for_device(i2c_dev->dev,
1259                                                    i2c_dev->dma_phys,
1260                                                    xfer_size, DMA_FROM_DEVICE);
1261
1262                         err = tegra_i2c_dma_submit(i2c_dev, xfer_size);
1263                         if (err)
1264                                 return err;
1265                 } else {
1266                         dma_sync_single_for_cpu(i2c_dev->dev,
1267                                                 i2c_dev->dma_phys,
1268                                                 xfer_size, DMA_TO_DEVICE);
1269                 }
1270         }
1271
1272         tegra_i2c_push_packet_header(i2c_dev, msg, end_state);
1273
1274         if (!i2c_dev->msg_read) {
1275                 if (i2c_dev->dma_mode) {
1276                         memcpy(i2c_dev->dma_buf + I2C_PACKET_HEADER_SIZE,
1277                                msg->buf, msg->len);
1278
1279                         dma_sync_single_for_device(i2c_dev->dev,
1280                                                    i2c_dev->dma_phys,
1281                                                    xfer_size, DMA_TO_DEVICE);
1282
1283                         err = tegra_i2c_dma_submit(i2c_dev, xfer_size);
1284                         if (err)
1285                                 return err;
1286                 } else {
1287                         tegra_i2c_fill_tx_fifo(i2c_dev);
1288                 }
1289         }
1290
1291         if (i2c_dev->hw->has_per_pkt_xfer_complete_irq)
1292                 int_mask |= I2C_INT_PACKET_XFER_COMPLETE;
1293
1294         if (!i2c_dev->dma_mode) {
1295                 if (msg->flags & I2C_M_RD)
1296                         int_mask |= I2C_INT_RX_FIFO_DATA_REQ;
1297                 else if (i2c_dev->msg_buf_remaining)
1298                         int_mask |= I2C_INT_TX_FIFO_DATA_REQ;
1299         }
1300
1301         tegra_i2c_unmask_irq(i2c_dev, int_mask);
1302         dev_dbg(i2c_dev->dev, "unmasked IRQ: %02x\n",
1303                 i2c_readl(i2c_dev, I2C_INT_MASK));
1304
1305         if (i2c_dev->dma_mode) {
1306                 time_left = tegra_i2c_wait_completion(i2c_dev,
1307                                                       &i2c_dev->dma_complete,
1308                                                       xfer_time);
1309
1310                 /*
1311                  * Synchronize DMA first, since dmaengine_terminate_sync()
1312                  * performs synchronization after the transfer's termination
1313                  * and we want to get a completion if transfer succeeded.
1314                  */
1315                 dmaengine_synchronize(i2c_dev->msg_read ?
1316                                       i2c_dev->rx_dma_chan :
1317                                       i2c_dev->tx_dma_chan);
1318
1319                 dmaengine_terminate_sync(i2c_dev->msg_read ?
1320                                          i2c_dev->rx_dma_chan :
1321                                          i2c_dev->tx_dma_chan);
1322
1323                 if (!time_left && !completion_done(&i2c_dev->dma_complete)) {
1324                         dev_err(i2c_dev->dev, "DMA transfer timed out\n");
1325                         tegra_i2c_init(i2c_dev);
1326                         return -ETIMEDOUT;
1327                 }
1328
1329                 if (i2c_dev->msg_read && i2c_dev->msg_err == I2C_ERR_NONE) {
1330                         dma_sync_single_for_cpu(i2c_dev->dev,
1331                                                 i2c_dev->dma_phys,
1332                                                 xfer_size, DMA_FROM_DEVICE);
1333
1334                         memcpy(i2c_dev->msg_buf, i2c_dev->dma_buf, msg->len);
1335                 }
1336         }
1337
1338         time_left = tegra_i2c_wait_completion(i2c_dev, &i2c_dev->msg_complete,
1339                                               xfer_time);
1340
1341         tegra_i2c_mask_irq(i2c_dev, int_mask);
1342
1343         if (time_left == 0) {
1344                 dev_err(i2c_dev->dev, "I2C transfer timed out\n");
1345                 tegra_i2c_init(i2c_dev);
1346                 return -ETIMEDOUT;
1347         }
1348
1349         dev_dbg(i2c_dev->dev, "transfer complete: %lu %d %d\n",
1350                 time_left, completion_done(&i2c_dev->msg_complete),
1351                 i2c_dev->msg_err);
1352
1353         i2c_dev->dma_mode = false;
1354
1355         err = tegra_i2c_error_recover(i2c_dev, msg);
1356         if (err)
1357                 return err;
1358
1359         return 0;
1360 }
1361
1362 static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
1363                           int num)
1364 {
1365         struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
1366         int i, ret;
1367
1368         ret = pm_runtime_get_sync(i2c_dev->dev);
1369         if (ret < 0) {
1370                 dev_err(i2c_dev->dev, "runtime resume failed %d\n", ret);
1371                 pm_runtime_put_noidle(i2c_dev->dev);
1372                 return ret;
1373         }
1374
1375         for (i = 0; i < num; i++) {
1376                 enum msg_end_type end_type = MSG_END_STOP;
1377
1378                 if (i < (num - 1)) {
1379                         /* check whether follow up message is coming */
1380                         if (msgs[i + 1].flags & I2C_M_NOSTART)
1381                                 end_type = MSG_END_CONTINUE;
1382                         else
1383                                 end_type = MSG_END_REPEAT_START;
1384                 }
1385                 ret = tegra_i2c_xfer_msg(i2c_dev, &msgs[i], end_type);
1386                 if (ret)
1387                         break;
1388         }
1389
1390         pm_runtime_put(i2c_dev->dev);
1391
1392         return ret ?: i;
1393 }
1394
1395 static int tegra_i2c_xfer_atomic(struct i2c_adapter *adap,
1396                                  struct i2c_msg msgs[], int num)
1397 {
1398         struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
1399         int ret;
1400
1401         i2c_dev->atomic_mode = true;
1402         ret = tegra_i2c_xfer(adap, msgs, num);
1403         i2c_dev->atomic_mode = false;
1404
1405         return ret;
1406 }
1407
1408 static u32 tegra_i2c_func(struct i2c_adapter *adap)
1409 {
1410         struct tegra_i2c_dev *i2c_dev = i2c_get_adapdata(adap);
1411         u32 ret = I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
1412                   I2C_FUNC_10BIT_ADDR | I2C_FUNC_PROTOCOL_MANGLING;
1413
1414         if (i2c_dev->hw->has_continue_xfer_support)
1415                 ret |= I2C_FUNC_NOSTART;
1416
1417         return ret;
1418 }
1419
1420 static const struct i2c_algorithm tegra_i2c_algo = {
1421         .master_xfer            = tegra_i2c_xfer,
1422         .master_xfer_atomic     = tegra_i2c_xfer_atomic,
1423         .functionality          = tegra_i2c_func,
1424 };
1425
1426 /* payload size is only 12 bit */
1427 static const struct i2c_adapter_quirks tegra_i2c_quirks = {
1428         .flags = I2C_AQ_NO_ZERO_LEN,
1429         .max_read_len = SZ_4K,
1430         .max_write_len = SZ_4K - I2C_PACKET_HEADER_SIZE,
1431 };
1432
1433 static const struct i2c_adapter_quirks tegra194_i2c_quirks = {
1434         .flags = I2C_AQ_NO_ZERO_LEN,
1435         .max_write_len = SZ_64K - I2C_PACKET_HEADER_SIZE,
1436 };
1437
1438 static struct i2c_bus_recovery_info tegra_i2c_recovery_info = {
1439         .recover_bus = tegra_i2c_issue_bus_clear,
1440 };
1441
1442 static const struct tegra_i2c_hw_feature tegra20_i2c_hw = {
1443         .has_continue_xfer_support = false,
1444         .has_per_pkt_xfer_complete_irq = false,
1445         .clk_divisor_hs_mode = 3,
1446         .clk_divisor_std_mode = 0,
1447         .clk_divisor_fast_mode = 0,
1448         .clk_divisor_fast_plus_mode = 0,
1449         .has_config_load_reg = false,
1450         .has_multi_master_mode = false,
1451         .has_slcg_override_reg = false,
1452         .has_mst_fifo = false,
1453         .quirks = &tegra_i2c_quirks,
1454         .supports_bus_clear = false,
1455         .has_apb_dma = true,
1456         .tlow_std_mode = 0x4,
1457         .thigh_std_mode = 0x2,
1458         .tlow_fast_fastplus_mode = 0x4,
1459         .thigh_fast_fastplus_mode = 0x2,
1460         .setup_hold_time_std_mode = 0x0,
1461         .setup_hold_time_fast_fast_plus_mode = 0x0,
1462         .setup_hold_time_hs_mode = 0x0,
1463         .has_interface_timing_reg = false,
1464 };
1465
1466 static const struct tegra_i2c_hw_feature tegra30_i2c_hw = {
1467         .has_continue_xfer_support = true,
1468         .has_per_pkt_xfer_complete_irq = false,
1469         .clk_divisor_hs_mode = 3,
1470         .clk_divisor_std_mode = 0,
1471         .clk_divisor_fast_mode = 0,
1472         .clk_divisor_fast_plus_mode = 0,
1473         .has_config_load_reg = false,
1474         .has_multi_master_mode = false,
1475         .has_slcg_override_reg = false,
1476         .has_mst_fifo = false,
1477         .quirks = &tegra_i2c_quirks,
1478         .supports_bus_clear = false,
1479         .has_apb_dma = true,
1480         .tlow_std_mode = 0x4,
1481         .thigh_std_mode = 0x2,
1482         .tlow_fast_fastplus_mode = 0x4,
1483         .thigh_fast_fastplus_mode = 0x2,
1484         .setup_hold_time_std_mode = 0x0,
1485         .setup_hold_time_fast_fast_plus_mode = 0x0,
1486         .setup_hold_time_hs_mode = 0x0,
1487         .has_interface_timing_reg = false,
1488 };
1489
1490 static const struct tegra_i2c_hw_feature tegra114_i2c_hw = {
1491         .has_continue_xfer_support = true,
1492         .has_per_pkt_xfer_complete_irq = true,
1493         .clk_divisor_hs_mode = 1,
1494         .clk_divisor_std_mode = 0x19,
1495         .clk_divisor_fast_mode = 0x19,
1496         .clk_divisor_fast_plus_mode = 0x10,
1497         .has_config_load_reg = false,
1498         .has_multi_master_mode = false,
1499         .has_slcg_override_reg = false,
1500         .has_mst_fifo = false,
1501         .quirks = &tegra_i2c_quirks,
1502         .supports_bus_clear = true,
1503         .has_apb_dma = true,
1504         .tlow_std_mode = 0x4,
1505         .thigh_std_mode = 0x2,
1506         .tlow_fast_fastplus_mode = 0x4,
1507         .thigh_fast_fastplus_mode = 0x2,
1508         .setup_hold_time_std_mode = 0x0,
1509         .setup_hold_time_fast_fast_plus_mode = 0x0,
1510         .setup_hold_time_hs_mode = 0x0,
1511         .has_interface_timing_reg = false,
1512 };
1513
1514 static const struct tegra_i2c_hw_feature tegra124_i2c_hw = {
1515         .has_continue_xfer_support = true,
1516         .has_per_pkt_xfer_complete_irq = true,
1517         .clk_divisor_hs_mode = 1,
1518         .clk_divisor_std_mode = 0x19,
1519         .clk_divisor_fast_mode = 0x19,
1520         .clk_divisor_fast_plus_mode = 0x10,
1521         .has_config_load_reg = true,
1522         .has_multi_master_mode = false,
1523         .has_slcg_override_reg = true,
1524         .has_mst_fifo = false,
1525         .quirks = &tegra_i2c_quirks,
1526         .supports_bus_clear = true,
1527         .has_apb_dma = true,
1528         .tlow_std_mode = 0x4,
1529         .thigh_std_mode = 0x2,
1530         .tlow_fast_fastplus_mode = 0x4,
1531         .thigh_fast_fastplus_mode = 0x2,
1532         .setup_hold_time_std_mode = 0x0,
1533         .setup_hold_time_fast_fast_plus_mode = 0x0,
1534         .setup_hold_time_hs_mode = 0x0,
1535         .has_interface_timing_reg = true,
1536 };
1537
1538 static const struct tegra_i2c_hw_feature tegra210_i2c_hw = {
1539         .has_continue_xfer_support = true,
1540         .has_per_pkt_xfer_complete_irq = true,
1541         .clk_divisor_hs_mode = 1,
1542         .clk_divisor_std_mode = 0x19,
1543         .clk_divisor_fast_mode = 0x19,
1544         .clk_divisor_fast_plus_mode = 0x10,
1545         .has_config_load_reg = true,
1546         .has_multi_master_mode = false,
1547         .has_slcg_override_reg = true,
1548         .has_mst_fifo = false,
1549         .quirks = &tegra_i2c_quirks,
1550         .supports_bus_clear = true,
1551         .has_apb_dma = true,
1552         .tlow_std_mode = 0x4,
1553         .thigh_std_mode = 0x2,
1554         .tlow_fast_fastplus_mode = 0x4,
1555         .thigh_fast_fastplus_mode = 0x2,
1556         .setup_hold_time_std_mode = 0,
1557         .setup_hold_time_fast_fast_plus_mode = 0,
1558         .setup_hold_time_hs_mode = 0,
1559         .has_interface_timing_reg = true,
1560 };
1561
1562 static const struct tegra_i2c_hw_feature tegra186_i2c_hw = {
1563         .has_continue_xfer_support = true,
1564         .has_per_pkt_xfer_complete_irq = true,
1565         .clk_divisor_hs_mode = 1,
1566         .clk_divisor_std_mode = 0x16,
1567         .clk_divisor_fast_mode = 0x19,
1568         .clk_divisor_fast_plus_mode = 0x10,
1569         .has_config_load_reg = true,
1570         .has_multi_master_mode = false,
1571         .has_slcg_override_reg = true,
1572         .has_mst_fifo = false,
1573         .quirks = &tegra_i2c_quirks,
1574         .supports_bus_clear = true,
1575         .has_apb_dma = false,
1576         .tlow_std_mode = 0x4,
1577         .thigh_std_mode = 0x3,
1578         .tlow_fast_fastplus_mode = 0x4,
1579         .thigh_fast_fastplus_mode = 0x2,
1580         .setup_hold_time_std_mode = 0,
1581         .setup_hold_time_fast_fast_plus_mode = 0,
1582         .setup_hold_time_hs_mode = 0,
1583         .has_interface_timing_reg = true,
1584 };
1585
1586 static const struct tegra_i2c_hw_feature tegra194_i2c_hw = {
1587         .has_continue_xfer_support = true,
1588         .has_per_pkt_xfer_complete_irq = true,
1589         .clk_divisor_hs_mode = 1,
1590         .clk_divisor_std_mode = 0x4f,
1591         .clk_divisor_fast_mode = 0x3c,
1592         .clk_divisor_fast_plus_mode = 0x16,
1593         .has_config_load_reg = true,
1594         .has_multi_master_mode = true,
1595         .has_slcg_override_reg = true,
1596         .has_mst_fifo = true,
1597         .quirks = &tegra194_i2c_quirks,
1598         .supports_bus_clear = true,
1599         .has_apb_dma = false,
1600         .tlow_std_mode = 0x8,
1601         .thigh_std_mode = 0x7,
1602         .tlow_fast_fastplus_mode = 0x2,
1603         .thigh_fast_fastplus_mode = 0x2,
1604         .setup_hold_time_std_mode = 0x08080808,
1605         .setup_hold_time_fast_fast_plus_mode = 0x02020202,
1606         .setup_hold_time_hs_mode = 0x090909,
1607         .has_interface_timing_reg = true,
1608 };
1609
1610 static const struct of_device_id tegra_i2c_of_match[] = {
1611         { .compatible = "nvidia,tegra194-i2c", .data = &tegra194_i2c_hw, },
1612         { .compatible = "nvidia,tegra186-i2c", .data = &tegra186_i2c_hw, },
1613         { .compatible = "nvidia,tegra210-i2c-vi", .data = &tegra210_i2c_hw, },
1614         { .compatible = "nvidia,tegra210-i2c", .data = &tegra210_i2c_hw, },
1615         { .compatible = "nvidia,tegra124-i2c", .data = &tegra124_i2c_hw, },
1616         { .compatible = "nvidia,tegra114-i2c", .data = &tegra114_i2c_hw, },
1617         { .compatible = "nvidia,tegra30-i2c", .data = &tegra30_i2c_hw, },
1618         { .compatible = "nvidia,tegra20-i2c", .data = &tegra20_i2c_hw, },
1619         { .compatible = "nvidia,tegra20-i2c-dvc", .data = &tegra20_i2c_hw, },
1620         {},
1621 };
1622 MODULE_DEVICE_TABLE(of, tegra_i2c_of_match);
1623
1624 static void tegra_i2c_parse_dt(struct tegra_i2c_dev *i2c_dev)
1625 {
1626         struct device_node *np = i2c_dev->dev->of_node;
1627         bool multi_mode;
1628         int err;
1629
1630         err = of_property_read_u32(np, "clock-frequency",
1631                                    &i2c_dev->bus_clk_rate);
1632         if (err)
1633                 i2c_dev->bus_clk_rate = I2C_MAX_STANDARD_MODE_FREQ;
1634
1635         multi_mode = of_property_read_bool(np, "multi-master");
1636         i2c_dev->multimaster_mode = multi_mode;
1637
1638         if (of_device_is_compatible(np, "nvidia,tegra20-i2c-dvc"))
1639                 i2c_dev->is_dvc = true;
1640
1641         if (of_device_is_compatible(np, "nvidia,tegra210-i2c-vi"))
1642                 i2c_dev->is_vi = true;
1643 }
1644
1645 static int tegra_i2c_init_clocks(struct tegra_i2c_dev *i2c_dev)
1646 {
1647         int err;
1648
1649         i2c_dev->clocks[i2c_dev->nclocks++].id = "div-clk";
1650
1651         if (i2c_dev->hw == &tegra20_i2c_hw || i2c_dev->hw == &tegra30_i2c_hw)
1652                 i2c_dev->clocks[i2c_dev->nclocks++].id = "fast-clk";
1653
1654         if (i2c_dev->is_vi)
1655                 i2c_dev->clocks[i2c_dev->nclocks++].id = "slow";
1656
1657         err = devm_clk_bulk_get(i2c_dev->dev, i2c_dev->nclocks,
1658                                 i2c_dev->clocks);
1659         if (err)
1660                 return err;
1661
1662         err = clk_bulk_prepare(i2c_dev->nclocks, i2c_dev->clocks);
1663         if (err)
1664                 return err;
1665
1666         i2c_dev->div_clk = i2c_dev->clocks[0].clk;
1667
1668         if (!i2c_dev->multimaster_mode)
1669                 return 0;
1670
1671         err = clk_enable(i2c_dev->div_clk);
1672         if (err) {
1673                 dev_err(i2c_dev->dev, "failed to enable div-clk: %d\n", err);
1674                 goto unprepare_clocks;
1675         }
1676
1677         return 0;
1678
1679 unprepare_clocks:
1680         clk_bulk_unprepare(i2c_dev->nclocks, i2c_dev->clocks);
1681
1682         return err;
1683 }
1684
1685 static void tegra_i2c_release_clocks(struct tegra_i2c_dev *i2c_dev)
1686 {
1687         if (i2c_dev->multimaster_mode)
1688                 clk_disable(i2c_dev->div_clk);
1689
1690         clk_bulk_unprepare(i2c_dev->nclocks, i2c_dev->clocks);
1691 }
1692
1693 static int tegra_i2c_init_hardware(struct tegra_i2c_dev *i2c_dev)
1694 {
1695         int ret;
1696
1697         ret = pm_runtime_get_sync(i2c_dev->dev);
1698         if (ret < 0)
1699                 dev_err(i2c_dev->dev, "runtime resume failed: %d\n", ret);
1700         else
1701                 ret = tegra_i2c_init(i2c_dev);
1702
1703         pm_runtime_put(i2c_dev->dev);
1704
1705         return ret;
1706 }
1707
1708 static int tegra_i2c_probe(struct platform_device *pdev)
1709 {
1710         struct tegra_i2c_dev *i2c_dev;
1711         struct resource *res;
1712         int err;
1713
1714         i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
1715         if (!i2c_dev)
1716                 return -ENOMEM;
1717
1718         platform_set_drvdata(pdev, i2c_dev);
1719
1720         init_completion(&i2c_dev->msg_complete);
1721         init_completion(&i2c_dev->dma_complete);
1722
1723         i2c_dev->hw = of_device_get_match_data(&pdev->dev);
1724         i2c_dev->cont_id = pdev->id;
1725         i2c_dev->dev = &pdev->dev;
1726
1727         i2c_dev->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1728         if (IS_ERR(i2c_dev->base))
1729                 return PTR_ERR(i2c_dev->base);
1730
1731         i2c_dev->base_phys = res->start;
1732
1733         err = platform_get_irq(pdev, 0);
1734         if (err < 0)
1735                 return err;
1736
1737         i2c_dev->irq = err;
1738
1739         /* interrupt will be enabled during of transfer time */
1740         irq_set_status_flags(i2c_dev->irq, IRQ_NOAUTOEN);
1741
1742         err = devm_request_threaded_irq(i2c_dev->dev, i2c_dev->irq,
1743                                         NULL, tegra_i2c_isr,
1744                                         IRQF_NO_SUSPEND | IRQF_ONESHOT,
1745                                         dev_name(i2c_dev->dev), i2c_dev);
1746         if (err)
1747                 return err;
1748
1749         i2c_dev->rst = devm_reset_control_get_exclusive(i2c_dev->dev, "i2c");
1750         if (IS_ERR(i2c_dev->rst)) {
1751                 dev_err_probe(i2c_dev->dev, PTR_ERR(i2c_dev->rst),
1752                               "failed to get reset control\n");
1753                 return PTR_ERR(i2c_dev->rst);
1754         }
1755
1756         tegra_i2c_parse_dt(i2c_dev);
1757
1758         err = tegra_i2c_init_clocks(i2c_dev);
1759         if (err)
1760                 return err;
1761
1762         err = tegra_i2c_init_dma(i2c_dev);
1763         if (err)
1764                 goto release_clocks;
1765
1766         /*
1767          * VI I2C is in VE power domain which is not always ON and not
1768          * IRQ-safe.  Thus, IRQ-safe device shouldn't be attached to a
1769          * non IRQ-safe domain because this prevents powering off the power
1770          * domain.
1771          *
1772          * VI I2C device shouldn't be marked as IRQ-safe because VI I2C won't
1773          * be used for atomic transfers.
1774          */
1775         if (!i2c_dev->is_vi)
1776                 pm_runtime_irq_safe(i2c_dev->dev);
1777
1778         pm_runtime_enable(i2c_dev->dev);
1779
1780         err = tegra_i2c_init_hardware(i2c_dev);
1781         if (err)
1782                 goto release_rpm;
1783
1784         i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
1785         i2c_dev->adapter.dev.of_node = i2c_dev->dev->of_node;
1786         i2c_dev->adapter.dev.parent = i2c_dev->dev;
1787         i2c_dev->adapter.retries = 1;
1788         i2c_dev->adapter.timeout = 6 * HZ;
1789         i2c_dev->adapter.quirks = i2c_dev->hw->quirks;
1790         i2c_dev->adapter.owner = THIS_MODULE;
1791         i2c_dev->adapter.class = I2C_CLASS_DEPRECATED;
1792         i2c_dev->adapter.algo = &tegra_i2c_algo;
1793         i2c_dev->adapter.nr = pdev->id;
1794
1795         if (i2c_dev->hw->supports_bus_clear)
1796                 i2c_dev->adapter.bus_recovery_info = &tegra_i2c_recovery_info;
1797
1798         strlcpy(i2c_dev->adapter.name, dev_name(i2c_dev->dev),
1799                 sizeof(i2c_dev->adapter.name));
1800
1801         err = i2c_add_numbered_adapter(&i2c_dev->adapter);
1802         if (err)
1803                 goto release_rpm;
1804
1805         return 0;
1806
1807 release_rpm:
1808         pm_runtime_disable(i2c_dev->dev);
1809
1810         tegra_i2c_release_dma(i2c_dev);
1811 release_clocks:
1812         tegra_i2c_release_clocks(i2c_dev);
1813
1814         return err;
1815 }
1816
1817 static int tegra_i2c_remove(struct platform_device *pdev)
1818 {
1819         struct tegra_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
1820
1821         i2c_del_adapter(&i2c_dev->adapter);
1822         pm_runtime_disable(i2c_dev->dev);
1823
1824         tegra_i2c_release_dma(i2c_dev);
1825         tegra_i2c_release_clocks(i2c_dev);
1826
1827         return 0;
1828 }
1829
1830 static int __maybe_unused tegra_i2c_runtime_resume(struct device *dev)
1831 {
1832         struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
1833         int err;
1834
1835         err = pinctrl_pm_select_default_state(dev);
1836         if (err)
1837                 return err;
1838
1839         err = clk_bulk_enable(i2c_dev->nclocks, i2c_dev->clocks);
1840         if (err)
1841                 return err;
1842
1843         /*
1844          * VI I2C device is attached to VE power domain which goes through
1845          * power ON/OFF during runtime PM resume/suspend, meaning that
1846          * controller needs to be re-initialized after power ON.
1847          */
1848         if (i2c_dev->is_vi) {
1849                 err = tegra_i2c_init(i2c_dev);
1850                 if (err)
1851                         goto disable_clocks;
1852         }
1853
1854         return 0;
1855
1856 disable_clocks:
1857         clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks);
1858
1859         return err;
1860 }
1861
1862 static int __maybe_unused tegra_i2c_runtime_suspend(struct device *dev)
1863 {
1864         struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
1865
1866         clk_bulk_disable(i2c_dev->nclocks, i2c_dev->clocks);
1867
1868         return pinctrl_pm_select_idle_state(dev);
1869 }
1870
1871 static int __maybe_unused tegra_i2c_suspend(struct device *dev)
1872 {
1873         struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
1874         int err;
1875
1876         i2c_mark_adapter_suspended(&i2c_dev->adapter);
1877
1878         if (!pm_runtime_status_suspended(dev)) {
1879                 err = tegra_i2c_runtime_suspend(dev);
1880                 if (err)
1881                         return err;
1882         }
1883
1884         return 0;
1885 }
1886
1887 static int __maybe_unused tegra_i2c_resume(struct device *dev)
1888 {
1889         struct tegra_i2c_dev *i2c_dev = dev_get_drvdata(dev);
1890         int err;
1891
1892         /*
1893          * We need to ensure that clocks are enabled so that registers can be
1894          * restored in tegra_i2c_init().
1895          */
1896         err = tegra_i2c_runtime_resume(dev);
1897         if (err)
1898                 return err;
1899
1900         err = tegra_i2c_init(i2c_dev);
1901         if (err)
1902                 return err;
1903
1904         /*
1905          * In case we are runtime suspended, disable clocks again so that we
1906          * don't unbalance the clock reference counts during the next runtime
1907          * resume transition.
1908          */
1909         if (pm_runtime_status_suspended(dev)) {
1910                 err = tegra_i2c_runtime_suspend(dev);
1911                 if (err)
1912                         return err;
1913         }
1914
1915         i2c_mark_adapter_resumed(&i2c_dev->adapter);
1916
1917         return 0;
1918 }
1919
1920 static const struct dev_pm_ops tegra_i2c_pm = {
1921         SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(tegra_i2c_suspend, tegra_i2c_resume)
1922         SET_RUNTIME_PM_OPS(tegra_i2c_runtime_suspend, tegra_i2c_runtime_resume,
1923                            NULL)
1924 };
1925
1926 static struct platform_driver tegra_i2c_driver = {
1927         .probe = tegra_i2c_probe,
1928         .remove = tegra_i2c_remove,
1929         .driver = {
1930                 .name = "tegra-i2c",
1931                 .of_match_table = tegra_i2c_of_match,
1932                 .pm = &tegra_i2c_pm,
1933         },
1934 };
1935 module_platform_driver(tegra_i2c_driver);
1936
1937 MODULE_DESCRIPTION("NVIDIA Tegra I2C Bus Controller driver");
1938 MODULE_AUTHOR("Colin Cross");
1939 MODULE_LICENSE("GPL v2");