drivers/soundwire/debugfs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 // Copyright(c) 2017-2019 Intel Corporation.
   3
   4 #include <linux/cleanup.h>
   5 #include <linux/device.h>
   6 #include <linux/debugfs.h>
   7 #include <linux/firmware.h>
   8 #include <linux/mod_devicetable.h>
   9 #include <linux/pm_runtime.h>
  10 #include <linux/slab.h>
  11 #include <linux/soundwire/sdw.h>
  12 #include <linux/soundwire/sdw_registers.h>
  13 #include "bus.h"
  14
  15 static struct dentry *sdw_debugfs_root;
  16
  17 void sdw_bus_debugfs_init(struct sdw_bus *bus)
  18 {
  19         char name[16];
  20
  21         if (!sdw_debugfs_root)
  22                 return;
  23
  24         /* create the debugfs master-N */
  25         snprintf(name, sizeof(name), "master-%d-%d", bus->controller_id, bus->link_id);
  26         bus->debugfs = debugfs_create_dir(name, sdw_debugfs_root);
  27 }
  28
  29 void sdw_bus_debugfs_exit(struct sdw_bus *bus)
  30 {
  31         debugfs_remove_recursive(bus->debugfs);
  32 }
  33
  34 #define RD_BUF (3 * PAGE_SIZE)
  35
  36 static ssize_t sdw_sprintf(struct sdw_slave *slave,
  37                            char *buf, size_t pos, unsigned int reg)
  38 {
  39         int value;
  40
  41         value = sdw_read_no_pm(slave, reg);
  42
  43         if (value < 0)
  44                 return scnprintf(buf + pos, RD_BUF - pos, "%3x\tXX\n", reg);
  45         else
  46                 return scnprintf(buf + pos, RD_BUF - pos,
  47                                 "%3x\t%2x\n", reg, value);
  48 }
  49
  50 static int sdw_slave_reg_show(struct seq_file *s_file, void *data)
  51 {
  52         struct sdw_slave *slave = s_file->private;
  53         ssize_t ret;
  54         int i, j;
  55
  56         char *buf __free(kfree) = kzalloc(RD_BUF, GFP_KERNEL);
  57         if (!buf)
  58                 return -ENOMEM;
  59
  60         ret = pm_runtime_get_sync(&slave->dev);
  61         if (ret < 0 && ret != -EACCES) {
  62                 pm_runtime_put_noidle(&slave->dev);
  63                 return ret;
  64         }
  65
  66         ret = scnprintf(buf, RD_BUF, "Register  Value\n");
  67
  68         /* DP0 non-banked registers */
  69         ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP0\n");
  70         for (i = SDW_DP0_INT; i <= SDW_DP0_PREPARECTRL; i++)
  71                 ret += sdw_sprintf(slave, buf, ret, i);
  72
  73         /* DP0 Bank 0 registers */
  74         ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n");
  75         ret += sdw_sprintf(slave, buf, ret, SDW_DP0_CHANNELEN);
  76         for (i = SDW_DP0_SAMPLECTRL1; i <= SDW_DP0_LANECTRL; i++)
  77                 ret += sdw_sprintf(slave, buf, ret, i);
  78
  79         /* DP0 Bank 1 registers */
  80         ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n");
  81         ret += sdw_sprintf(slave, buf, ret,
  82                         SDW_DP0_CHANNELEN + SDW_BANK1_OFFSET);
  83         for (i = SDW_DP0_SAMPLECTRL1 + SDW_BANK1_OFFSET;
  84                         i <= SDW_DP0_LANECTRL + SDW_BANK1_OFFSET; i++)
  85                 ret += sdw_sprintf(slave, buf, ret, i);
  86
  87         /* SCP registers */
  88         ret += scnprintf(buf + ret, RD_BUF - ret, "\nSCP\n");
  89         for (i = SDW_SCP_INT1; i <= SDW_SCP_BUS_CLOCK_BASE; i++)
  90                 ret += sdw_sprintf(slave, buf, ret, i);
  91         for (i = SDW_SCP_DEVID_0; i <= SDW_SCP_DEVID_5; i++)
  92                 ret += sdw_sprintf(slave, buf, ret, i);
  93         for (i = SDW_SCP_FRAMECTRL_B0; i <= SDW_SCP_BUSCLOCK_SCALE_B0; i++)
  94                 ret += sdw_sprintf(slave, buf, ret, i);
  95         for (i = SDW_SCP_FRAMECTRL_B1; i <= SDW_SCP_BUSCLOCK_SCALE_B1; i++)
  96                 ret += sdw_sprintf(slave, buf, ret, i);
  97         for (i = SDW_SCP_PHY_OUT_CTRL_0; i <= SDW_SCP_PHY_OUT_CTRL_7; i++)
  98                 ret += sdw_sprintf(slave, buf, ret, i);
  99
 100
 101         /*
 102          * SCP Bank 0/1 registers are read-only and cannot be
 103          * retrieved from the Slave. The Master typically keeps track
 104          * of the current frame size so the information can be found
 105          * in other places
 106          */
 107
 108         /* DP1..14 registers */
 109         for (i = 1; SDW_VALID_PORT_RANGE(i); i++) {
 110
 111                 /* DPi registers */
 112                 ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP%d\n", i);
 113                 for (j = SDW_DPN_INT(i); j <= SDW_DPN_PREPARECTRL(i); j++)
 114                         ret += sdw_sprintf(slave, buf, ret, j);
 115
 116                 /* DPi Bank0 registers */
 117                 ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n");
 118                 for (j = SDW_DPN_CHANNELEN_B0(i);
 119                      j <= SDW_DPN_LANECTRL_B0(i); j++)
 120                         ret += sdw_sprintf(slave, buf, ret, j);
 121
 122                 /* DPi Bank1 registers */
 123                 ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n");
 124                 for (j = SDW_DPN_CHANNELEN_B1(i);
 125                      j <= SDW_DPN_LANECTRL_B1(i); j++)
 126                         ret += sdw_sprintf(slave, buf, ret, j);
 127         }
 128
 129         seq_printf(s_file, "%s", buf);
 130
 131         pm_runtime_mark_last_busy(&slave->dev);
 132         pm_runtime_put(&slave->dev);
 133
 134         return 0;
 135 }
 136 DEFINE_SHOW_ATTRIBUTE(sdw_slave_reg);
 137
 138 #define MAX_CMD_BYTES 256
 139
 140 static int cmd;
 141 static u32 start_addr;
 142 static size_t num_bytes;
 143 static u8 read_buffer[MAX_CMD_BYTES];
 144 static char *firmware_file;
 145
 146 static int set_command(void *data, u64 value)
 147 {
 148         struct sdw_slave *slave = data;
 149
 150         if (value > 1)
 151                 return -EINVAL;
 152
 153         /* Userspace changed the hardware state behind the kernel's back */
 154         add_taint(TAINT_USER, LOCKDEP_STILL_OK);
 155
 156         dev_dbg(&slave->dev, "command: %s\n", value ? "read" : "write");
 157         cmd = value;
 158
 159         return 0;
 160 }
 161 DEFINE_DEBUGFS_ATTRIBUTE(set_command_fops, NULL,
 162                          set_command, "%llu\n");
 163
 164 static int set_start_address(void *data, u64 value)
 165 {
 166         struct sdw_slave *slave = data;
 167
 168         /* Userspace changed the hardware state behind the kernel's back */
 169         add_taint(TAINT_USER, LOCKDEP_STILL_OK);
 170
 171         dev_dbg(&slave->dev, "start address %#llx\n", value);
 172
 173         start_addr = value;
 174
 175         return 0;
 176 }
 177 DEFINE_DEBUGFS_ATTRIBUTE(set_start_address_fops, NULL,
 178                          set_start_address, "%llu\n");
 179
 180 static int set_num_bytes(void *data, u64 value)
 181 {
 182         struct sdw_slave *slave = data;
 183
 184         if (value == 0 || value > MAX_CMD_BYTES)
 185                 return -EINVAL;
 186
 187         /* Userspace changed the hardware state behind the kernel's back */
 188         add_taint(TAINT_USER, LOCKDEP_STILL_OK);
 189
 190         dev_dbg(&slave->dev, "number of bytes %lld\n", value);
 191
 192         num_bytes = value;
 193
 194         return 0;
 195 }
 196 DEFINE_DEBUGFS_ATTRIBUTE(set_num_bytes_fops, NULL,
 197                          set_num_bytes, "%llu\n");
 198
 199 static int cmd_go(void *data, u64 value)
 200 {
 201         struct sdw_slave *slave = data;
 202         int ret;
 203
 204         if (value != 1)
 205                 return -EINVAL;
 206
 207         /* one last check */
 208         if (start_addr > SDW_REG_MAX ||
 209             num_bytes == 0 || num_bytes > MAX_CMD_BYTES)
 210                 return -EINVAL;
 211
 212         ret = pm_runtime_get_sync(&slave->dev);
 213         if (ret < 0 && ret != -EACCES) {
 214                 pm_runtime_put_noidle(&slave->dev);
 215                 return ret;
 216         }
 217
 218         /* Userspace changed the hardware state behind the kernel's back */
 219         add_taint(TAINT_USER, LOCKDEP_STILL_OK);
 220
 221         dev_dbg(&slave->dev, "starting command\n");
 222
 223         if (cmd == 0) {
 224                 const struct firmware *fw;
 225
 226                 ret = request_firmware(&fw, firmware_file, &slave->dev);
 227                 if (ret < 0) {
 228                         dev_err(&slave->dev, "firmware %s not found\n", firmware_file);
 229                         goto out;
 230                 }
 231
 232                 if (fw->size != num_bytes) {
 233                         dev_err(&slave->dev,
 234                                 "firmware %s: unexpected size %zd, desired %zd\n",
 235                                 firmware_file, fw->size, num_bytes);
 236                         release_firmware(fw);
 237                         goto out;
 238                 }
 239
 240                 ret = sdw_nwrite_no_pm(slave, start_addr, num_bytes, fw->data);
 241                 release_firmware(fw);
 242         } else {
 243                 ret = sdw_nread_no_pm(slave, start_addr, num_bytes, read_buffer);
 244         }
 245
 246         dev_dbg(&slave->dev, "command completed %d\n", ret);
 247
 248 out:
 249         pm_runtime_mark_last_busy(&slave->dev);
 250         pm_runtime_put(&slave->dev);
 251
 252         return ret;
 253 }
 254 DEFINE_DEBUGFS_ATTRIBUTE(cmd_go_fops, NULL,
 255                          cmd_go, "%llu\n");
 256
 257 #define MAX_LINE_LEN 128
 258
 259 static int read_buffer_show(struct seq_file *s_file, void *data)
 260 {
 261         char buf[MAX_LINE_LEN];
 262         int i;
 263
 264         if (num_bytes == 0 || num_bytes > MAX_CMD_BYTES)
 265                 return -EINVAL;
 266
 267         for (i = 0; i < num_bytes; i++) {
 268                 scnprintf(buf, MAX_LINE_LEN, "address %#x val 0x%02x\n",
 269                           start_addr + i, read_buffer[i]);
 270                 seq_printf(s_file, "%s", buf);
 271         }
 272
 273         return 0;
 274 }
 275 DEFINE_SHOW_ATTRIBUTE(read_buffer);
 276
 277 void sdw_slave_debugfs_init(struct sdw_slave *slave)
 278 {
 279         struct dentry *master;
 280         struct dentry *d;
 281         char name[32];
 282
 283         master = slave->bus->debugfs;
 284
 285         /* create the debugfs slave-name */
 286         snprintf(name, sizeof(name), "%s", dev_name(&slave->dev));
 287         d = debugfs_create_dir(name, master);
 288
 289         debugfs_create_file("registers", 0400, d, slave, &sdw_slave_reg_fops);
 290
 291         /* interface to send arbitrary commands */
 292         debugfs_create_file("command", 0200, d, slave, &set_command_fops);
 293         debugfs_create_file("start_address", 0200, d, slave, &set_start_address_fops);
 294         debugfs_create_file("num_bytes", 0200, d, slave, &set_num_bytes_fops);
 295         debugfs_create_file("go", 0200, d, slave, &cmd_go_fops);
 296
 297         debugfs_create_file("read_buffer", 0400, d, slave, &read_buffer_fops);
 298         firmware_file = NULL;
 299         debugfs_create_str("firmware_file", 0200, d, &firmware_file);
 300
 301         slave->debugfs = d;
 302 }
 303
 304 void sdw_slave_debugfs_exit(struct sdw_slave *slave)
 305 {
 306         debugfs_remove_recursive(slave->debugfs);
 307 }
 308
 309 void sdw_debugfs_init(void)
 310 {
 311         sdw_debugfs_root = debugfs_create_dir("soundwire", NULL);
 312 }
 313
 314 void sdw_debugfs_exit(void)
 315 {
 316         debugfs_remove_recursive(sdw_debugfs_root);
 317 }