sound/soc/samsung/s3c24xx_uda134x.c

   1 /*
   2  * Modifications by Christian Pellegrin <chripell@evolware.org>
   3  *
   4  * s3c24xx_uda134x.c  --  S3C24XX_UDA134X ALSA SoC Audio board driver
   5  *
   6  * Copyright 2007 Dension Audio Systems Ltd.
   7  * Author: Zoltan Devai
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/clk.h>
  15 #include <linux/gpio.h>
  16 #include <linux/module.h>
  17
  18 #include <sound/soc.h>
  19 #include <sound/s3c24xx_uda134x.h>
  20
  21 #include "regs-iis.h"
  22
  23 #include "s3c24xx-i2s.h"
  24
  25 /* #define ENFORCE_RATES 1 */
  26 /*
  27   Unfortunately the S3C24XX in master mode has a limited capacity of
  28   generating the clock for the codec. If you define this only rates
  29   that are really available will be enforced. But be careful, most
  30   user level application just want the usual sampling frequencies (8,
  31   11.025, 22.050, 44.1 kHz) and anyway resampling is a costly
  32   operation for embedded systems. So if you aren't very lucky or your
  33   hardware engineer wasn't very forward-looking it's better to leave
  34   this undefined. If you do so an approximate value for the requested
  35   sampling rate in the range -/+ 5% will be chosen. If this in not
  36   possible an error will be returned.
  37 */
  38
  39 static struct clk *xtal;
  40 static struct clk *pclk;
  41 /* this is need because we don't have a place where to keep the
  42  * pointers to the clocks in each substream. We get the clocks only
  43  * when we are actually using them so we don't block stuff like
  44  * frequency change or oscillator power-off */
  45 static int clk_users;
  46 static DEFINE_MUTEX(clk_lock);
  47
  48 static unsigned int rates[33 * 2];
  49 #ifdef ENFORCE_RATES
  50 static struct snd_pcm_hw_constraint_list hw_constraints_rates = {
  51         .count  = ARRAY_SIZE(rates),
  52         .list   = rates,
  53         .mask   = 0,
  54 };
  55 #endif
  56
  57 static struct platform_device *s3c24xx_uda134x_snd_device;
  58
  59 static int s3c24xx_uda134x_startup(struct snd_pcm_substream *substream)
  60 {
  61         int ret = 0;
  62 #ifdef ENFORCE_RATES
  63         struct snd_pcm_runtime *runtime = substream->runtime;
  64 #endif
  65
  66         mutex_lock(&clk_lock);
  67         pr_debug("%s %d\n", __func__, clk_users);
  68         if (clk_users == 0) {
  69                 xtal = clk_get(&s3c24xx_uda134x_snd_device->dev, "xtal");
  70                 if (IS_ERR(xtal)) {
  71                         printk(KERN_ERR "%s cannot get xtal\n", __func__);
  72                         ret = PTR_ERR(xtal);
  73                 } else {
  74                         pclk = clk_get(&s3c24xx_uda134x_snd_device->dev,
  75                                        "pclk");
  76                         if (IS_ERR(pclk)) {
  77                                 printk(KERN_ERR "%s cannot get pclk\n",
  78                                        __func__);
  79                                 clk_put(xtal);
  80                                 ret = PTR_ERR(pclk);
  81                         }
  82                 }
  83                 if (!ret) {
  84                         int i, j;
  85
  86                         for (i = 0; i < 2; i++) {
  87                                 int fs = i ? 256 : 384;
  88
  89                                 rates[i*33] = clk_get_rate(xtal) / fs;
  90                                 for (j = 1; j < 33; j++)
  91                                         rates[i*33 + j] = clk_get_rate(pclk) /
  92                                                 (j * fs);
  93                         }
  94                 }
  95         }
  96         clk_users += 1;
  97         mutex_unlock(&clk_lock);
  98         if (!ret) {
  99 #ifdef ENFORCE_RATES
 100                 ret = snd_pcm_hw_constraint_list(runtime, 0,
 101                                                  SNDRV_PCM_HW_PARAM_RATE,
 102                                                  &hw_constraints_rates);
 103                 if (ret < 0)
 104                         printk(KERN_ERR "%s cannot set constraints\n",
 105                                __func__);
 106 #endif
 107         }
 108         return ret;
 109 }
 110
 111 static void s3c24xx_uda134x_shutdown(struct snd_pcm_substream *substream)
 112 {
 113         mutex_lock(&clk_lock);
 114         pr_debug("%s %d\n", __func__, clk_users);
 115         clk_users -= 1;
 116         if (clk_users == 0) {
 117                 clk_put(xtal);
 118                 xtal = NULL;
 119                 clk_put(pclk);
 120                 pclk = NULL;
 121         }
 122         mutex_unlock(&clk_lock);
 123 }
 124
 125 static int s3c24xx_uda134x_hw_params(struct snd_pcm_substream *substream,
 126                                         struct snd_pcm_hw_params *params)
 127 {
 128         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 129         struct snd_soc_dai *codec_dai = rtd->codec_dai;
 130         struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
 131         unsigned int clk = 0;
 132         int ret = 0;
 133         int clk_source, fs_mode;
 134         unsigned long rate = params_rate(params);
 135         long err, cerr;
 136         unsigned int div;
 137         int i, bi;
 138
 139         err = 999999;
 140         bi = 0;
 141         for (i = 0; i < 2*33; i++) {
 142                 cerr = rates[i] - rate;
 143                 if (cerr < 0)
 144                         cerr = -cerr;
 145                 if (cerr < err) {
 146                         err = cerr;
 147                         bi = i;
 148                 }
 149         }
 150         if (bi / 33 == 1)
 151                 fs_mode = S3C2410_IISMOD_256FS;
 152         else
 153                 fs_mode = S3C2410_IISMOD_384FS;
 154         if (bi % 33 == 0) {
 155                 clk_source = S3C24XX_CLKSRC_MPLL;
 156                 div = 1;
 157         } else {
 158                 clk_source = S3C24XX_CLKSRC_PCLK;
 159                 div = bi % 33;
 160         }
 161         pr_debug("%s desired rate %lu, %d\n", __func__, rate, bi);
 162
 163         clk = (fs_mode == S3C2410_IISMOD_384FS ? 384 : 256) * rate;
 164         pr_debug("%s will use: %s %s %d sysclk %d err %ld\n", __func__,
 165                  fs_mode == S3C2410_IISMOD_384FS ? "384FS" : "256FS",
 166                  clk_source == S3C24XX_CLKSRC_MPLL ? "MPLLin" : "PCLK",
 167                  div, clk, err);
 168
 169         if ((err * 100 / rate) > 5) {
 170                 printk(KERN_ERR "S3C24XX_UDA134X: effective frequency "
 171                        "too different from desired (%ld%%)\n",
 172                        err * 100 / rate);
 173                 return -EINVAL;
 174         }
 175
 176         ret = snd_soc_dai_set_sysclk(cpu_dai, clk_source , clk,
 177                         SND_SOC_CLOCK_IN);
 178         if (ret < 0)
 179                 return ret;
 180
 181         ret = snd_soc_dai_set_clkdiv(cpu_dai, S3C24XX_DIV_MCLK, fs_mode);
 182         if (ret < 0)
 183                 return ret;
 184
 185         ret = snd_soc_dai_set_clkdiv(cpu_dai, S3C24XX_DIV_BCLK,
 186                         S3C2410_IISMOD_32FS);
 187         if (ret < 0)
 188                 return ret;
 189
 190         ret = snd_soc_dai_set_clkdiv(cpu_dai, S3C24XX_DIV_PRESCALER,
 191                         S3C24XX_PRESCALE(div, div));
 192         if (ret < 0)
 193                 return ret;
 194
 195         /* set the codec system clock for DAC and ADC */
 196         ret = snd_soc_dai_set_sysclk(codec_dai, 0, clk,
 197                         SND_SOC_CLOCK_OUT);
 198         if (ret < 0)
 199                 return ret;
 200
 201         return 0;
 202 }
 203
 204 static struct snd_soc_ops s3c24xx_uda134x_ops = {
 205         .startup = s3c24xx_uda134x_startup,
 206         .shutdown = s3c24xx_uda134x_shutdown,
 207         .hw_params = s3c24xx_uda134x_hw_params,
 208 };
 209
 210 static struct snd_soc_dai_link s3c24xx_uda134x_dai_link = {
 211         .name = "UDA134X",
 212         .stream_name = "UDA134X",
 213         .codec_name = "uda134x-codec",
 214         .codec_dai_name = "uda134x-hifi",
 215         .cpu_dai_name = "s3c24xx-iis",
 216         .dai_fmt = SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_NB_NF |
 217                    SND_SOC_DAIFMT_CBS_CFS,
 218         .ops = &s3c24xx_uda134x_ops,
 219         .platform_name  = "s3c24xx-iis",
 220 };
 221
 222 static struct snd_soc_card snd_soc_s3c24xx_uda134x = {
 223         .name = "S3C24XX_UDA134X",
 224         .owner = THIS_MODULE,
 225         .dai_link = &s3c24xx_uda134x_dai_link,
 226         .num_links = 1,
 227 };
 228
 229 static struct s3c24xx_uda134x_platform_data *s3c24xx_uda134x_l3_pins;
 230
 231 static void setdat(int v)
 232 {
 233         gpio_set_value(s3c24xx_uda134x_l3_pins->l3_data, v > 0);
 234 }
 235
 236 static void setclk(int v)
 237 {
 238         gpio_set_value(s3c24xx_uda134x_l3_pins->l3_clk, v > 0);
 239 }
 240
 241 static void setmode(int v)
 242 {
 243         gpio_set_value(s3c24xx_uda134x_l3_pins->l3_mode, v > 0);
 244 }
 245
 246 /* FIXME - This must be codec platform data but in which board file ?? */
 247 static struct uda134x_platform_data s3c24xx_uda134x = {
 248         .l3 = {
 249                 .setdat = setdat,
 250                 .setclk = setclk,
 251                 .setmode = setmode,
 252                 .data_hold = 1,
 253                 .data_setup = 1,
 254                 .clock_high = 1,
 255                 .mode_hold = 1,
 256                 .mode = 1,
 257                 .mode_setup = 1,
 258         },
 259 };
 260
 261 static int s3c24xx_uda134x_setup_pin(int pin, char *fun)
 262 {
 263         if (gpio_request(pin, "s3c24xx_uda134x") < 0) {
 264                 printk(KERN_ERR "S3C24XX_UDA134X SoC Audio: "
 265                        "l3 %s pin already in use", fun);
 266                 return -EBUSY;
 267         }
 268         gpio_direction_output(pin, 0);
 269         return 0;
 270 }
 271
 272 static int s3c24xx_uda134x_probe(struct platform_device *pdev)
 273 {
 274         int ret;
 275
 276         printk(KERN_INFO "S3C24XX_UDA134X SoC Audio driver\n");
 277
 278         s3c24xx_uda134x_l3_pins = pdev->dev.platform_data;
 279         if (s3c24xx_uda134x_l3_pins == NULL) {
 280                 printk(KERN_ERR "S3C24XX_UDA134X SoC Audio: "
 281                        "unable to find platform data\n");
 282                 return -ENODEV;
 283         }
 284         s3c24xx_uda134x.power = s3c24xx_uda134x_l3_pins->power;
 285         s3c24xx_uda134x.model = s3c24xx_uda134x_l3_pins->model;
 286
 287         if (s3c24xx_uda134x_setup_pin(s3c24xx_uda134x_l3_pins->l3_data,
 288                                       "data") < 0)
 289                 return -EBUSY;
 290         if (s3c24xx_uda134x_setup_pin(s3c24xx_uda134x_l3_pins->l3_clk,
 291                                       "clk") < 0) {
 292                 gpio_free(s3c24xx_uda134x_l3_pins->l3_data);
 293                 return -EBUSY;
 294         }
 295         if (s3c24xx_uda134x_setup_pin(s3c24xx_uda134x_l3_pins->l3_mode,
 296                                       "mode") < 0) {
 297                 gpio_free(s3c24xx_uda134x_l3_pins->l3_data);
 298                 gpio_free(s3c24xx_uda134x_l3_pins->l3_clk);
 299                 return -EBUSY;
 300         }
 301
 302         s3c24xx_uda134x_snd_device = platform_device_alloc("soc-audio", -1);
 303         if (!s3c24xx_uda134x_snd_device) {
 304                 printk(KERN_ERR "S3C24XX_UDA134X SoC Audio: "
 305                        "Unable to register\n");
 306                 return -ENOMEM;
 307         }
 308
 309         platform_set_drvdata(s3c24xx_uda134x_snd_device,
 310                              &snd_soc_s3c24xx_uda134x);
 311         platform_device_add_data(s3c24xx_uda134x_snd_device, &s3c24xx_uda134x, sizeof(s3c24xx_uda134x));
 312         ret = platform_device_add(s3c24xx_uda134x_snd_device);
 313         if (ret) {
 314                 printk(KERN_ERR "S3C24XX_UDA134X SoC Audio: Unable to add\n");
 315                 platform_device_put(s3c24xx_uda134x_snd_device);
 316         }
 317
 318         return ret;
 319 }
 320
 321 static int s3c24xx_uda134x_remove(struct platform_device *pdev)
 322 {
 323         platform_device_unregister(s3c24xx_uda134x_snd_device);
 324         gpio_free(s3c24xx_uda134x_l3_pins->l3_data);
 325         gpio_free(s3c24xx_uda134x_l3_pins->l3_clk);
 326         gpio_free(s3c24xx_uda134x_l3_pins->l3_mode);
 327         return 0;
 328 }
 329
 330 static struct platform_driver s3c24xx_uda134x_driver = {
 331         .probe  = s3c24xx_uda134x_probe,
 332         .remove = s3c24xx_uda134x_remove,
 333         .driver = {
 334                 .name = "s3c24xx_uda134x",
 335         },
 336 };
 337
 338 module_platform_driver(s3c24xx_uda134x_driver);
 339
 340 MODULE_AUTHOR("Zoltan Devai, Christian Pellegrin <chripell@evolware.org>");
 341 MODULE_DESCRIPTION("S3C24XX_UDA134X ALSA SoC audio driver");
 342 MODULE_LICENSE("GPL");