[PATCH v4 1/6] ASoC: ops: improve snd_soc_get_volsw

[Niranjan H Y <niranjan.hy@ti.com>]

* add error handling in case register read fails
* add support for clamping the values if the register
  value read is greater than max value

Signed-off-by: Niranjan H Y <niranjan.hy@ti.com>
---
 sound/soc/soc-ops.c | 38 +++++++++++++++++++++++++++++---------
 1 file changed, 29 insertions(+), 9 deletions(-)

diff --git a/sound/soc/soc-ops.c b/sound/soc/soc-ops.c
index a629e0eac..59e91741b 100644
--- a/sound/soc/soc-ops.c
+++ b/sound/soc/soc-ops.c
@@ -111,10 +111,14 @@ int snd_soc_put_enum_double(struct snd_kcontrol *kcontrol,
 EXPORT_SYMBOL_GPL(snd_soc_put_enum_double);
 
 static int soc_mixer_reg_to_ctl(struct soc_mixer_control *mc, unsigned int reg_val,
-				unsigned int mask, unsigned int shift, int max)
+				unsigned int mask, unsigned int shift, int max,
+				bool clamp)
 {
 	int val = (reg_val >> shift) & mask;
 
+	if (clamp)
+		val = clamp(val, 0, mc->max);
+
 	if (mc->sign_bit)
 		val = sign_extend32(val, mc->sign_bit);
 
@@ -245,29 +249,44 @@ static int soc_put_volsw(struct snd_kcontrol *kcontrol,
 
 static int soc_get_volsw(struct snd_kcontrol *kcontrol,
 			 struct snd_ctl_elem_value *ucontrol,
-			 struct soc_mixer_control *mc, int mask, int max)
+			 struct soc_mixer_control *mc, int mask, int max,
+			 bool clamp)
 {
 	struct snd_soc_component *component = snd_kcontrol_chip(kcontrol);
 	unsigned int reg_val;
-	int val;
+	int val, ret = 0;
 
 	reg_val = snd_soc_component_read(component, mc->reg);
-	val = soc_mixer_reg_to_ctl(mc, reg_val, mask, mc->shift, max);
+	val = reg_val;
+	if (val < 0) {
+		ret = val;
+		goto get_volsw_done;
+	}
+
+	val = soc_mixer_reg_to_ctl(mc, reg_val, mask, mc->shift, max, clamp);
 
 	ucontrol->value.integer.value[0] = val;
 
 	if (snd_soc_volsw_is_stereo(mc)) {
 		if (mc->reg == mc->rreg) {
-			val = soc_mixer_reg_to_ctl(mc, reg_val, mask, mc->rshift, max);
+			val = soc_mixer_reg_to_ctl(mc, reg_val, mask, mc->rshift,
+						   max, clamp);
 		} else {
 			reg_val = snd_soc_component_read(component, mc->rreg);
-			val = soc_mixer_reg_to_ctl(mc, reg_val, mask, mc->shift, max);
+			val = reg_val;
+			if (val < 0) {
+				ret = val;
+				goto get_volsw_done;
+			}
+			val = soc_mixer_reg_to_ctl(mc, reg_val, mask,
+						   mc->shift, max, clamp);
 		}
 
 		ucontrol->value.integer.value[1] = val;
 	}
 
-	return 0;
+get_volsw_done:
+	return ret;
 }
 
 /**
@@ -330,7 +349,8 @@ int snd_soc_get_volsw(struct snd_kcontrol *kcontrol,
 		(struct soc_mixer_control *)kcontrol->private_value;
 	unsigned int mask = soc_mixer_mask(mc);
 
-	return soc_get_volsw(kcontrol, ucontrol, mc, mask, mc->max - mc->min);
+	return soc_get_volsw(kcontrol, ucontrol, mc, mask,
+			     mc->max - mc->min, false);
 }
 EXPORT_SYMBOL_GPL(snd_soc_get_volsw);
 
@@ -372,7 +392,7 @@ int snd_soc_get_volsw_sx(struct snd_kcontrol *kcontrol,
 		(struct soc_mixer_control *)kcontrol->private_value;
 	unsigned int mask = soc_mixer_sx_mask(mc);
 
-	return soc_get_volsw(kcontrol, ucontrol, mc, mask, mc->max);
+	return soc_get_volsw(kcontrol, ucontrol, mc, mask, mc->max, false);
 }
 EXPORT_SYMBOL_GPL(snd_soc_get_volsw_sx);
 
-- 
2.45.2