[PATCH 1/5] omap-alsa-tsc2101: code, debug and comment cleanups

Following patch-set cleanups and simplifies the code in
omap-alsa-tsc2101 and omap-alsa-tsc2101-mixer.

Signed-off-by: lamikr <lamikr@cc.jyu.fi>

diff --git a/sound/arm/omap/omap-alsa-tsc2101.c b/sound/arm/omap/omap-alsa-tsc2101.c
index a0096cb62fce5c8beee1c63dd8baa2ba4039529a..c3abe1df3d88b54574fc2752fb93d69d37a081a4 100644 (file)
--- a/sound/arm/omap/omap-alsa-tsc2101.c
+++ b/sound/arm/omap/omap-alsa-tsc2101.c
@@ -136,7 +136,7 @@ static snd_pcm_hardware_t tsc2101_snd_omap_alsa_capture = {
 };
 
 /* 
- * Simplified write for tsc Audio
+ * Simplified write for tsc2101 audio registers.
  */
 inline void tsc2101_audio_write(u8 address, u16 data)
 {
@@ -144,7 +144,7 @@ inline void tsc2101_audio_write(u8 address, u16 data)
 }
 
 /* 
- * Simplified read for tsc  Audio
+ * Simplified read for tsc2101 audio registers.
  */
 inline u16 tsc2101_audio_read(u8 address)
 {
@@ -246,14 +246,17 @@ void tsc2101_set_samplerate(long sample_rate)
 #endif                         /* #ifdef TSC_MASTER */
        tsc2101_audio_write(TSC2101_AUDIO_CTRL_3, data);
 
-       /* program the PLLs */
+       /* Program the PLLs. This code assumes that the 12 Mhz MCLK is in use.
+         * If MCLK rate is something else, these values must be changed.
+        * See the tsc2101 specification for the details.
+        */
        if (rate_reg_info[count].fs_44kHz) {
-               /* 44.1 khz - 12 MHz Mclk */
+               /* samplerate = (44.1kHZ / x), where x is int. */
                tsc2101_audio_write(TSC2101_PLL_PROG_1, PLL1_PLLSEL |
                                PLL1_PVAL(1) | PLL1_I_VAL(7));  /* PVAL 1; I_VAL 7 */
                tsc2101_audio_write(TSC2101_PLL_PROG_2, PLL2_D_VAL(0x1490));    /* D_VAL 5264 */
        } else {
-               /* 48 khz - 12 Mhz Mclk */
+               /* samplerate = (48.kHZ / x), where x is int. */
                tsc2101_audio_write(TSC2101_PLL_PROG_1, PLL1_PLLSEL |
                               PLL1_PVAL(1) | PLL1_I_VAL(8));   /* PVAL 1; I_VAL 8 */
                tsc2101_audio_write(TSC2101_PLL_PROG_2, PLL2_D_VAL(0x780));     /* D_VAL 1920 */
@@ -317,21 +320,14 @@ int tsc2101_clock_on(void)
                       CODEC_CLOCK);
        }
        curRate = (uint)clk_get_rate(tsc2101_mclk);
-       DPRINTK("old clock rate = %d\n", curRate);
        if (curRate != CODEC_CLOCK) {
                err     = clk_set_rate(tsc2101_mclk, CODEC_CLOCK);
                if (err) {
                        printk(KERN_WARNING
                               "Cannot set MCLK clock rate for TSC2101 CODEC, error code = %d\n", err);
-                       //return -ECANCELED;
+                       return -ECANCELED;
                }
        }
-       else
-       {
-               printk(KERN_INFO
-                      "omap_alsa_tsc2101_clock_on(), no need to change rate, no need to change clock rate, rate already %d Hz.\n",
-                      CODEC_CLOCK);
-       }
        err             = clk_enable(tsc2101_mclk);
        curRate         = (uint)clk_get_rate(tsc2101_mclk);
        curUseCount     = clk_get_usecount(tsc2101_mclk);
@@ -349,8 +345,7 @@ int tsc2101_clock_on(void)
 }
 
 /*
- * Do some sanity check, turn clock off and then turn
- *  codec audio off
+ * Do some sanity check, turn clock off and then turn codec audio off
  */
 int tsc2101_clock_off(void) 
 {
@@ -374,10 +369,6 @@ int tsc2101_clock_off(void)
        tsc2101_audio_write(TSC2101_CODEC_POWER_CTRL,
                            ~(CPC_SP1PWDN | CPC_SP2PWDN | CPC_BASSBC));
        DPRINTK("audio codec off\n");
-#ifdef DUMP_TSC2101_AUDIO_REGISTERS
-       printk("tsc2101_clock_off()\n");
-       dump_tsc2101_audio_reg();
-#endif 
        return 0;       
 }
 
@@ -420,18 +411,22 @@ static struct platform_driver omap_alsa_driver = {
 };
 
 static int __init omap_alsa_tsc2101_init(void)
-{
-       int err;
-       
+{      
        ADEBUG();
-       err = platform_driver_register(&omap_alsa_driver);
-
-       return err;
+#ifdef DUMP_TSC2101_AUDIO_REGISTERS
+       printk("omap_alsa_tsc2101_init()\n");
+       dump_tsc2101_audio_reg();
+#endif
+       return platform_driver_register(&omap_alsa_driver);
 }
 
 static void __exit omap_alsa_tsc2101_exit(void)
 {
        ADEBUG();
+#ifdef DUMP_TSC2101_AUDIO_REGISTERS
+       printk("omap_alsa_tsc2101_exit()\n");
+       dump_tsc2101_audio_reg();
+#endif
        platform_driver_unregister(&omap_alsa_driver);
 }