ASoC: tlv320dac33: Error handling for broken chip

Correct/Implement handling of broken chip.
Fail the soc_prope if the communication with the chip
fails (can not read chip ID).

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@nokia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>

diff --git a/sound/soc/codecs/tlv320dac33.c b/sound/soc/codecs/tlv320dac33.c
index d251ff5..fed1458 100644 (file)
--- a/sound/soc/codecs/tlv320dac33.c
+++ b/sound/soc/codecs/tlv320dac33.c
@@ -200,7 +200,7 @@ static int dac33_read(struct snd_soc_codec *codec, unsigned int reg,
                      u8 *value)
 {
        struct tlv320dac33_priv *dac33 = snd_soc_codec_get_drvdata(codec);
-       int val;
+       int val, ret = 0;
 
        *value = reg & 0xff;
 
@@ -210,6 +210,7 @@ static int dac33_read(struct snd_soc_codec *codec, unsigned int reg,
                if (val < 0) {
                        dev_err(codec->dev, "Read failed (%d)\n", val);
                        value[0] = dac33_read_reg_cache(codec, reg);
+                       ret = val;
                } else {
                        value[0] = val;
                        dac33_write_reg_cache(codec, reg, val);
@@ -218,7 +219,7 @@ static int dac33_read(struct snd_soc_codec *codec, unsigned int reg,
                value[0] = dac33_read_reg_cache(codec, reg);
        }
 
-       return 0;
+       return ret;
 }
 
 static int dac33_write(struct snd_soc_codec *codec, unsigned int reg,
@@ -329,13 +330,18 @@ static void dac33_init_chip(struct snd_soc_codec *codec)
                    dac33_read_reg_cache(codec, DAC33_LINER_TO_RLO_VOL));
 }
 
-static inline void dac33_read_id(struct snd_soc_codec *codec)
+static inline int dac33_read_id(struct snd_soc_codec *codec)
 {
+       int i, ret = 0;
        u8 reg;
 
-       dac33_read(codec, DAC33_DEVICE_ID_MSB, &reg);
-       dac33_read(codec, DAC33_DEVICE_ID_LSB, &reg);
-       dac33_read(codec, DAC33_DEVICE_REV_ID, &reg);
+       for (i = 0; i < 3; i++) {
+               ret = dac33_read(codec, DAC33_DEVICE_ID_MSB + i, &reg);
+               if (ret < 0)
+                       break;
+       }
+
+       return ret;
 }
 
 static inline void dac33_soft_power(struct snd_soc_codec *codec, int power)
@@ -1414,9 +1420,15 @@ static int dac33_soc_probe(struct snd_soc_codec *codec)
                dev_err(codec->dev, "Failed to power up codec: %d\n", ret);
                goto err_power;
        }
-       dac33_read_id(codec);
+       ret = dac33_read_id(codec);
        dac33_hard_power(codec, 0);
 
+       if (ret < 0) {
+               dev_err(codec->dev, "Failed to read chip ID: %d\n", ret);
+               ret = -ENODEV;
+               goto err_power;
+       }
+
        /* Check if the IRQ number is valid and request it */
        if (dac33->irq >= 0) {
                ret = request_irq(dac33->irq, dac33_interrupt_handler,