thinkpad-acpi: fix ALSA callback return status
Clemens Ladisch reports that thinkpad-acpi improperly implements the
ALSA API, and always returns 0 for success for the "put" callbacks
while the API requires it to return "1" when the control value has
been changed in the hardware/firmware.
Rework the volume subdriver to be able to properly implement the ALSA
API. Based on a patch by Clemens Ladisch <clemens@ladisch.de>.
This fix is also needed on 2.6.33.
Reported-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: stable@kernel.org
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 5d02cc0..e7b0c3b 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -6541,7 +6541,8 @@
return volume_set_status_ec(status);
}
-static int volume_set_mute_ec(const bool mute)
+/* returns < 0 on error, 0 on no change, 1 on change */
+static int __volume_set_mute_ec(const bool mute)
{
int rc;
u8 s, n;
@@ -6556,22 +6557,37 @@
n = (mute) ? s | TP_EC_AUDIO_MUTESW_MSK :
s & ~TP_EC_AUDIO_MUTESW_MSK;
- if (n != s)
+ if (n != s) {
rc = volume_set_status_ec(n);
+ if (!rc)
+ rc = 1;
+ }
unlock:
mutex_unlock(&volume_mutex);
return rc;
}
-static int volume_set_mute(const bool mute)
+static int volume_alsa_set_mute(const bool mute)
{
- dbg_printk(TPACPI_DBG_MIXER, "trying to %smute\n",
+ dbg_printk(TPACPI_DBG_MIXER, "ALSA: trying to %smute\n",
(mute) ? "" : "un");
- return volume_set_mute_ec(mute);
+ return __volume_set_mute_ec(mute);
}
-static int volume_set_volume_ec(const u8 vol)
+static int volume_set_mute(const bool mute)
+{
+ int rc;
+
+ dbg_printk(TPACPI_DBG_MIXER, "trying to %smute\n",
+ (mute) ? "" : "un");
+
+ rc = __volume_set_mute_ec(mute);
+ return (rc < 0) ? rc : 0;
+}
+
+/* returns < 0 on error, 0 on no change, 1 on change */
+static int __volume_set_volume_ec(const u8 vol)
{
int rc;
u8 s, n;
@@ -6588,19 +6604,22 @@
n = (s & ~TP_EC_AUDIO_LVL_MSK) | vol;
- if (n != s)
+ if (n != s) {
rc = volume_set_status_ec(n);
+ if (!rc)
+ rc = 1;
+ }
unlock:
mutex_unlock(&volume_mutex);
return rc;
}
-static int volume_set_volume(const u8 vol)
+static int volume_alsa_set_volume(const u8 vol)
{
dbg_printk(TPACPI_DBG_MIXER,
- "trying to set volume level to %hu\n", vol);
- return volume_set_volume_ec(vol);
+ "ALSA: trying to set volume level to %hu\n", vol);
+ return __volume_set_volume_ec(vol);
}
static void volume_alsa_notify_change(void)
@@ -6647,7 +6666,7 @@
static int volume_alsa_vol_put(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
- return volume_set_volume(ucontrol->value.integer.value[0]);
+ return volume_alsa_set_volume(ucontrol->value.integer.value[0]);
}
#define volume_alsa_mute_info snd_ctl_boolean_mono_info
@@ -6670,7 +6689,7 @@
static int volume_alsa_mute_put(struct snd_kcontrol *kcontrol,
struct snd_ctl_elem_value *ucontrol)
{
- return volume_set_mute(!ucontrol->value.integer.value[0]);
+ return volume_alsa_set_mute(!ucontrol->value.integer.value[0]);
}
static struct snd_kcontrol_new volume_alsa_control_vol __devinitdata = {