CHROMIUM: ASoC: Import entire upstream ASoC tree

sound/soc/ep93xx/ep93xx-i2s.c

 /*
  * linux/sound/soc/ep93xx-i2s.c
  * EP93xx I2S driver
  *
  * Copyright (C) 2010 Ryan Mallon <ryan@bluewatersys.com>
  *
  * Based on the original driver by:
  *   Copyright (C) 2007 Chase Douglas <chasedouglas@gmail>
  *   Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
  *
@@ skipping 249 matching lines @@
         default:
                 return -EINVAL;
         }
 
         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
                 ep93xx_i2s_write_reg(info, EP93XX_I2S_TXWRDLEN, word_len);
         else
                 ep93xx_i2s_write_reg(info, EP93XX_I2S_RXWRDLEN, word_len);
 
         /*
-         * Calculate the sdiv (bit clock) and lrdiv (left/right clock) values.
-         * If the lrclk is pulse length is larger than the word size, then the
-         * bit clock will be gated for the unused bits.
+         * EP93xx I2S module can be setup so SCLK / LRCLK value can be
+         * 32, 64, 128. MCLK / SCLK value can be 2 and 4.
+         * We set LRCLK equal to `rate' and minimum SCLK / LRCLK 
+         * value is 64, because our sample size is 32 bit * 2 channels.
+         * I2S standard permits us to transmit more bits than
+         * the codec uses.
          */
-        div = (clk_get_rate(info->mclk) / params_rate(params)) *
-                params_channels(params);
+        div = clk_get_rate(info->mclk) / params_rate(params);
         for (sdiv = 2; sdiv <= 4; sdiv += 2)
-                for (lrdiv = 32; lrdiv <= 128; lrdiv <<= 1)
+                for (lrdiv = 64; lrdiv <= 128; lrdiv <<= 1)
                         if (sdiv * lrdiv == div) {
                                 found = 1;
                                 goto out;
                         }
 out:
         if (!found)
                 return -EINVAL;
 
         err = clk_set_rate(info->sclk, clk_get_rate(info->mclk) / sdiv);
         if (err)
@@ skipping 46 matching lines @@
 #endif
 
 static struct snd_soc_dai_ops ep93xx_i2s_dai_ops = {
         .startup        = ep93xx_i2s_startup,
         .shutdown       = ep93xx_i2s_shutdown,
         .hw_params      = ep93xx_i2s_hw_params,
         .set_sysclk     = ep93xx_i2s_set_sysclk,
         .set_fmt        = ep93xx_i2s_set_dai_fmt,
 };
 
-#define EP93XX_I2S_FORMATS (SNDRV_PCM_FMTBIT_S16_LE | \
-                            SNDRV_PCM_FMTBIT_S24_LE | \
-                            SNDRV_PCM_FMTBIT_S32_LE)
+#define EP93XX_I2S_FORMATS (SNDRV_PCM_FMTBIT_S32_LE)
 
 static struct snd_soc_dai_driver ep93xx_i2s_dai = {
         .symmetric_rates= 1,
         .suspend        = ep93xx_i2s_suspend,
         .resume         = ep93xx_i2s_resume,
         .playback       = {
                 .channels_min   = 2,
                 .channels_max   = 2,
-                .rates          = SNDRV_PCM_RATE_8000_48000,
+                .rates          = SNDRV_PCM_RATE_8000_96000,
                 .formats        = EP93XX_I2S_FORMATS,
         },
         .capture        = {
                  .channels_min  = 2,
                  .channels_max  = 2,
-                 .rates         = SNDRV_PCM_RATE_8000_48000,
+                 .rates         = SNDRV_PCM_RATE_8000_96000,
                  .formats       = EP93XX_I2S_FORMATS,
         },
         .ops            = &ep93xx_i2s_dai_ops,
 };
 
 static int ep93xx_i2s_probe(struct platform_device *pdev)
 {
         struct ep93xx_i2s_info *info;
         struct resource *res;
         int err;
@@ skipping 98 matching lines @@
         platform_driver_unregister(&ep93xx_i2s_driver);
 }
 
 module_init(ep93xx_i2s_init);
 module_exit(ep93xx_i2s_exit);
 
 MODULE_ALIAS("platform:ep93xx-i2s");
 MODULE_AUTHOR("Ryan Mallon <ryan@bluewatersys.com>");
 MODULE_DESCRIPTION("EP93XX I2S driver");
 MODULE_LICENSE("GPL");