[PATCH v1 1/4] ALSA: hda: cs35l41: Clean up Firmware Load Controls

From: Stefan Binding
Date: Fri Apr 14 2023 - 11:27:26 EST


Ensure Firmware Load control and Firmware Type control
returns 1 when the value changes.

Remove fw_mutex from firmware load control put, since it is
unnecessary, and prevents any possibility of mutex inversion.

Signed-off-by: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>
---
sound/pci/hda/cs35l41_hda.c | 24 ++++++++++--------------
1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/sound/pci/hda/cs35l41_hda.c b/sound/pci/hda/cs35l41_hda.c
index b5210abb5141f..d100189e15b83 100644
--- a/sound/pci/hda/cs35l41_hda.c
+++ b/sound/pci/hda/cs35l41_hda.c
@@ -835,34 +835,26 @@ static int cs35l41_fw_load_ctl_put(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
struct cs35l41_hda *cs35l41 = snd_kcontrol_chip(kcontrol);
- unsigned int ret = 0;
-
- mutex_lock(&cs35l41->fw_mutex);

if (cs35l41->request_fw_load == ucontrol->value.integer.value[0])
- goto err;
+ return 0;

if (cs35l41->fw_request_ongoing) {
dev_dbg(cs35l41->dev, "Existing request not complete\n");
- ret = -EBUSY;
- goto err;
+ return -EBUSY;
}

/* Check if playback is ongoing when initial request is made */
if (cs35l41->playback_started) {
dev_err(cs35l41->dev, "Cannot Load/Unload firmware during Playback\n");
- ret = -EBUSY;
- goto err;
+ return -EBUSY;
}

cs35l41->fw_request_ongoing = true;
cs35l41->request_fw_load = ucontrol->value.integer.value[0];
schedule_work(&cs35l41->fw_load_work);

-err:
- mutex_unlock(&cs35l41->fw_mutex);
-
- return ret;
+ return 1;
}

static int cs35l41_fw_type_ctl_get(struct snd_kcontrol *kcontrol,
@@ -881,8 +873,12 @@ static int cs35l41_fw_type_ctl_put(struct snd_kcontrol *kcontrol,
struct cs35l41_hda *cs35l41 = snd_kcontrol_chip(kcontrol);

if (ucontrol->value.enumerated.item[0] < HDA_CS_DSP_NUM_FW) {
- cs35l41->firmware_type = ucontrol->value.enumerated.item[0];
- return 0;
+ if (cs35l41->firmware_type != ucontrol->value.enumerated.item[0]) {
+ cs35l41->firmware_type = ucontrol->value.enumerated.item[0];
+ return 1;
+ } else {
+ return 0;
+ }
}

return -EINVAL;
--
2.34.1