drivers/sound/rockchip_i2s.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2018 Google LLC
   4  * Copyright 2014 Rockchip Electronics Co., Ltd.
   5  * Taken from dc i2s/rockchip.c
   6  */
   7
   8 #define LOG_CATEGORY UCLASS_I2S
   9
  10 #include <common.h>
  11 #include <dm.h>
  12 #include <i2s.h>
  13 #include <log.h>
  14 #include <sound.h>
  15 #include <asm/io.h>
  16 #include <linux/bitops.h>
  17
  18 struct rk_i2s_regs {
  19         u32 txcr;               /* I2S_TXCR, 0x00 */
  20         u32 rxcr;               /* I2S_RXCR, 0x04 */
  21         u32 ckr;                /* I2S_CKR, 0x08 */
  22         u32 fifolr;             /* I2S_FIFOLR, 0x0C */
  23         u32 dmacr;              /* I2S_DMACR, 0x10 */
  24         u32 intcr;              /* I2S_INTCR, 0x14 */
  25         u32 intsr;              /* I2S_INTSR, 0x18 */
  26         u32 xfer;               /* I2S_XFER, 0x1C */
  27         u32 clr;                /* I2S_CLR, 0x20 */
  28         u32 txdr;               /* I2S_TXDR, 0x24 */
  29         u32 rxdr;               /* I2S_RXDR, 0x28 */
  30 };
  31
  32 enum {
  33         /* I2S_XFER */
  34         I2S_RX_TRAN_BIT         = BIT(1),
  35         I2S_TX_TRAN_BIT         = BIT(0),
  36         I2S_TRAN_MASK           = 3 << 0,
  37
  38         /* I2S_TXCKR */
  39         I2S_MCLK_DIV_SHIFT      = 16,
  40         I2S_MCLK_DIV_MASK       = (0xff << I2S_MCLK_DIV_SHIFT),
  41
  42         I2S_RX_SCLK_DIV_SHIFT   = 8,
  43         I2S_RX_SCLK_DIV_MASK    = 0xff << I2S_RX_SCLK_DIV_SHIFT,
  44         I2S_TX_SCLK_DIV_SHIFT   = 0,
  45         I2S_TX_SCLK_DIV_MASK    = 0xff << I2S_TX_SCLK_DIV_SHIFT,
  46
  47         I2S_DATA_WIDTH_SHIFT    = 0,
  48         I2S_DATA_WIDTH_MASK     = 0x1f << I2S_DATA_WIDTH_SHIFT,
  49 };
  50
  51 static int rockchip_i2s_init(struct i2s_uc_priv *priv)
  52 {
  53         struct rk_i2s_regs *regs = (struct rk_i2s_regs *)priv->base_address;
  54         u32 bps = priv->bitspersample;
  55         u32 lrf = priv->rfs;
  56         u32 chn = priv->channels;
  57         u32 mode = 0;
  58
  59         clrbits_le32(&regs->xfer, I2S_TX_TRAN_BIT);
  60         mode = readl(&regs->txcr) & ~0x1f;
  61         switch (priv->bitspersample) {
  62         case 16:
  63         case 24:
  64                 mode |= (priv->bitspersample - 1) << I2S_DATA_WIDTH_SHIFT;
  65                 break;
  66         default:
  67                 log_err("Invalid sample size input %d\n", priv->bitspersample);
  68                 return -EINVAL;
  69         }
  70         writel(mode, &regs->txcr);
  71
  72         mode = readl(&regs->ckr) & ~I2S_MCLK_DIV_MASK;
  73         mode |= (lrf / (bps * chn) - 1) << I2S_MCLK_DIV_SHIFT;
  74
  75         mode &= ~I2S_TX_SCLK_DIV_MASK;
  76         mode |= (priv->bitspersample * priv->channels - 1) <<
  77                          I2S_TX_SCLK_DIV_SHIFT;
  78         writel(mode, &regs->ckr);
  79
  80         return 0;
  81 }
  82
  83 static int i2s_send_data(struct rk_i2s_regs *regs, u32 *data, uint length)
  84 {
  85         for (int i = 0; i < min(32u, length); i++)
  86                 writel(*data++, &regs->txdr);
  87
  88         length -= min(32u, length);
  89
  90         /* enable both tx and rx */
  91         setbits_le32(&regs->xfer, I2S_TRAN_MASK);
  92         while (length) {
  93                 if ((readl(&regs->fifolr) & 0x3f) < 0x20) {
  94                         writel(*data++, &regs->txdr);
  95                         length--;
  96                 }
  97         }
  98         while (readl(&regs->fifolr) & 0x3f)
  99                 /* wait until FIFO empty */;
 100         clrbits_le32(&regs->xfer, I2S_TRAN_MASK);
 101         writel(0, &regs->clr);
 102
 103         return 0;
 104 }
 105
 106 static int rockchip_i2s_tx_data(struct udevice *dev, void *data, uint data_size)
 107 {
 108         struct i2s_uc_priv *priv = dev_get_uclass_priv(dev);
 109         struct rk_i2s_regs *regs = (struct rk_i2s_regs *)priv->base_address;
 110
 111         return i2s_send_data(regs, data, data_size / sizeof(u32));
 112 }
 113
 114 static int rockchip_i2s_probe(struct udevice *dev)
 115 {
 116         struct i2s_uc_priv *priv = dev_get_uclass_priv(dev);
 117         ulong base;
 118
 119         base = dev_read_addr(dev);
 120         if (base == FDT_ADDR_T_NONE) {
 121                 log_debug("Missing i2s base\n");
 122                 return -EINVAL;
 123         }
 124         priv->base_address = base;
 125         priv->id = 1;
 126         priv->audio_pll_clk = 4800000;
 127         priv->samplingrate = 48000;
 128         priv->bitspersample = 16;
 129         priv->channels = 2;
 130         priv->rfs = 256;
 131         priv->bfs = 32;
 132
 133         return rockchip_i2s_init(priv);
 134 }
 135
 136 static const struct i2s_ops rockchip_i2s_ops = {
 137         .tx_data        = rockchip_i2s_tx_data,
 138 };
 139
 140 static const struct udevice_id rockchip_i2s_ids[] = {
 141         { .compatible = "rockchip,rk3288-i2s" },
 142         { }
 143 };
 144
 145 U_BOOT_DRIVER(rockchip_i2s) = {
 146         .name           = "rockchip_i2s",
 147         .id             = UCLASS_I2S,
 148         .of_match       = rockchip_i2s_ids,
 149         .probe          = rockchip_i2s_probe,
 150         .ops            = &rockchip_i2s_ops,
 151 };