ASoC: codec: wm8960: add additional probe check for codec identification

The wm8960 codec is not readable, resulting in a NACK for address 0x3d (8-bit).
This can partially indicate it. For example: wm8962 codec use the same address
but is readable. This additional probe check will help prevent loading the wm8960
module incorrectly on wm8962 hardware.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230713222513.1636591-1-Frank.Li@nxp.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/wm8960.c b/sound/soc/codecs/wm8960.c
index 366f5d7..b2c1432 100644 (file)
--- a/sound/soc/codecs/wm8960.c
+++ b/sound/soc/codecs/wm8960.c
@@ -1415,6 +1415,7 @@ static int wm8960_i2c_probe(struct i2c_client *i2c)
        struct wm8960_data *pdata = dev_get_platdata(&i2c->dev);
        struct wm8960_priv *wm8960;
        int ret;
+       u8 val;
 
        wm8960 = devm_kzalloc(&i2c->dev, sizeof(struct wm8960_priv),
                              GFP_KERNEL);
@@ -1436,6 +1437,12 @@ static int wm8960_i2c_probe(struct i2c_client *i2c)
        else if (i2c->dev.of_node)
                wm8960_set_pdata_from_of(i2c, &wm8960->pdata);
 
+       ret = i2c_master_recv(i2c, &val, sizeof(val));
+       if (ret >= 0) {
+               dev_err(&i2c->dev, "Not wm8960, wm8960 reg can not read by i2c\n");
+               return -EINVAL;
+       }
+
        ret = wm8960_reset(wm8960->regmap);
        if (ret != 0) {
                dev_err(&i2c->dev, "Failed to issue reset\n");