[PATCH] aoa: add locking to tas codec
Johannes Berg
johannes at sipsolutions.net
Thu Sep 14 18:06:16 EST 2006
Looks like I completely forgot to do this. This patch adds locking to
the tas codec so two userspace programs can't hit the controls at the
same time. Tested on my powerbook, but I obviously can't find any
problems even without it since it doesn't do SMP.
Signed-off-by: Johannes Berg <johannes at sipsolutions.net>
--- a/sound/aoa/codecs/snd-aoa-codec-tas.c 2006-09-13 22:05:49.849647141 +0200
+++ b/sound/aoa/codecs/snd-aoa-codec-tas.c 2006-09-13 22:06:16.859647141 +0200
@@ -66,6 +66,8 @@
#include <asm/prom.h>
#include <linux/delay.h>
#include <linux/module.h>
+#include <linux/mutex.h>
+
MODULE_AUTHOR("Johannes Berg <johannes at sipsolutions.net>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("tas codec driver for snd-aoa");
@@ -91,6 +93,10 @@ struct tas {
u8 bass, treble;
u8 acr;
int drc_range;
+ /* protects hardware access against concurrency from
+ * userspace when hitting controls and during
+ * codec init/suspend/resume */
+ struct mutex mtx;
};
static int tas_reset_init(struct tas *tas);
@@ -231,8 +237,10 @@ static int tas_snd_vol_get(struct snd_kc
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
ucontrol->value.integer.value[0] = tas->cached_volume_l;
ucontrol->value.integer.value[1] = tas->cached_volume_r;
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -241,14 +249,18 @@ static int tas_snd_vol_put(struct snd_kc
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
if (tas->cached_volume_l == ucontrol->value.integer.value[0]
- && tas->cached_volume_r == ucontrol->value.integer.value[1])
+ && tas->cached_volume_r == ucontrol->value.integer.value[1]) {
+ mutex_unlock(&tas->mtx);
return 0;
+ }
tas->cached_volume_l = ucontrol->value.integer.value[0];
tas->cached_volume_r = ucontrol->value.integer.value[1];
if (tas->hw_enabled)
tas_set_volume(tas);
+ mutex_unlock(&tas->mtx);
return 1;
}
@@ -276,8 +288,10 @@ static int tas_snd_mute_get(struct snd_k
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
ucontrol->value.integer.value[0] = !tas->mute_l;
ucontrol->value.integer.value[1] = !tas->mute_r;
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -286,14 +300,18 @@ static int tas_snd_mute_put(struct snd_k
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
if (tas->mute_l == !ucontrol->value.integer.value[0]
- && tas->mute_r == !ucontrol->value.integer.value[1])
+ && tas->mute_r == !ucontrol->value.integer.value[1]) {
+ mutex_unlock(&tas->mtx);
return 0;
+ }
tas->mute_l = !ucontrol->value.integer.value[0];
tas->mute_r = !ucontrol->value.integer.value[1];
if (tas->hw_enabled)
tas_set_volume(tas);
+ mutex_unlock(&tas->mtx);
return 1;
}
@@ -322,8 +340,10 @@ static int tas_snd_mixer_get(struct snd_
struct tas *tas = snd_kcontrol_chip(kcontrol);
int idx = kcontrol->private_value;
+ mutex_lock(&tas->mtx);
ucontrol->value.integer.value[0] = tas->mixer_l[idx];
ucontrol->value.integer.value[1] = tas->mixer_r[idx];
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -334,15 +354,19 @@ static int tas_snd_mixer_put(struct snd_
struct tas *tas = snd_kcontrol_chip(kcontrol);
int idx = kcontrol->private_value;
+ mutex_lock(&tas->mtx);
if (tas->mixer_l[idx] == ucontrol->value.integer.value[0]
- && tas->mixer_r[idx] == ucontrol->value.integer.value[1])
+ && tas->mixer_r[idx] == ucontrol->value.integer.value[1]) {
+ mutex_unlock(&tas->mtx);
return 0;
+ }
tas->mixer_l[idx] = ucontrol->value.integer.value[0];
tas->mixer_r[idx] = ucontrol->value.integer.value[1];
if (tas->hw_enabled)
tas_set_mixer(tas);
+ mutex_unlock(&tas->mtx);
return 1;
}
@@ -375,7 +399,9 @@ static int tas_snd_drc_range_get(struct
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
ucontrol->value.integer.value[0] = tas->drc_range;
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -384,12 +410,16 @@ static int tas_snd_drc_range_put(struct
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
- if (tas->drc_range == ucontrol->value.integer.value[0])
+ mutex_lock(&tas->mtx);
+ if (tas->drc_range == ucontrol->value.integer.value[0]) {
+ mutex_unlock(&tas->mtx);
return 0;
+ }
tas->drc_range = ucontrol->value.integer.value[0];
if (tas->hw_enabled)
tas3004_set_drc(tas);
+ mutex_unlock(&tas->mtx);
return 1;
}
@@ -417,7 +447,9 @@ static int tas_snd_drc_switch_get(struct
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
ucontrol->value.integer.value[0] = tas->drc_enabled;
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -426,12 +458,16 @@ static int tas_snd_drc_switch_put(struct
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
- if (tas->drc_enabled == ucontrol->value.integer.value[0])
+ mutex_lock(&tas->mtx);
+ if (tas->drc_enabled == ucontrol->value.integer.value[0]) {
+ mutex_unlock(&tas->mtx);
return 0;
+ }
tas->drc_enabled = ucontrol->value.integer.value[0];
if (tas->hw_enabled)
tas3004_set_drc(tas);
+ mutex_unlock(&tas->mtx);
return 1;
}
@@ -463,7 +499,9 @@ static int tas_snd_capture_source_get(st
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
ucontrol->value.enumerated.item[0] = !!(tas->acr & TAS_ACR_INPUT_B);
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -471,15 +509,21 @@ static int tas_snd_capture_source_put(st
struct snd_ctl_elem_value *ucontrol)
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
- int oldacr = tas->acr;
+ int oldacr;
+
+ mutex_lock(&tas->mtx);
+ oldacr = tas->acr;
tas->acr &= ~TAS_ACR_INPUT_B;
if (ucontrol->value.enumerated.item[0])
tas->acr |= TAS_ACR_INPUT_B;
- if (oldacr == tas->acr)
+ if (oldacr == tas->acr) {
+ mutex_unlock(&tas->mtx);
return 0;
+ }
if (tas->hw_enabled)
tas_write_reg(tas, TAS_REG_ACR, 1, &tas->acr);
+ mutex_unlock(&tas->mtx);
return 1;
}
@@ -518,7 +562,9 @@ static int tas_snd_treble_get(struct snd
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
ucontrol->value.integer.value[0] = tas->treble;
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -527,12 +573,16 @@ static int tas_snd_treble_put(struct snd
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
- if (tas->treble == ucontrol->value.integer.value[0])
+ mutex_lock(&tas->mtx);
+ if (tas->treble == ucontrol->value.integer.value[0]) {
+ mutex_unlock(&tas->mtx);
return 0;
+ }
tas->treble = ucontrol->value.integer.value[0];
if (tas->hw_enabled)
tas_set_treble(tas);
+ mutex_unlock(&tas->mtx);
return 1;
}
@@ -560,7 +610,9 @@ static int tas_snd_bass_get(struct snd_k
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
+ mutex_lock(&tas->mtx);
ucontrol->value.integer.value[0] = tas->bass;
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -569,12 +621,16 @@ static int tas_snd_bass_put(struct snd_k
{
struct tas *tas = snd_kcontrol_chip(kcontrol);
- if (tas->bass == ucontrol->value.integer.value[0])
+ mutex_lock(&tas->mtx);
+ if (tas->bass == ucontrol->value.integer.value[0]) {
+ mutex_unlock(&tas->mtx);
return 0;
+ }
tas->bass = ucontrol->value.integer.value[0];
if (tas->hw_enabled)
tas_set_bass(tas);
+ mutex_unlock(&tas->mtx);
return 1;
}
@@ -628,16 +684,16 @@ static int tas_reset_init(struct tas *ta
tmp = TAS_MCS_SCLK64 | TAS_MCS_SPORT_MODE_I2S | TAS_MCS_SPORT_WL_24BIT;
if (tas_write_reg(tas, TAS_REG_MCS, 1, &tmp))
- return -ENODEV;
+ goto outerr;
tas->acr |= TAS_ACR_ANALOG_PDOWN | TAS_ACR_B_MONAUREAL |
TAS_ACR_B_MON_SEL_RIGHT;
if (tas_write_reg(tas, TAS_REG_ACR, 1, &tas->acr))
- return -ENODEV;
+ goto outerr;
tmp = 0;
if (tas_write_reg(tas, TAS_REG_MCS2, 1, &tmp))
- return -ENODEV;
+ goto outerr;
tas3004_set_drc(tas);
@@ -649,9 +705,11 @@ static int tas_reset_init(struct tas *ta
tas->acr &= ~TAS_ACR_ANALOG_PDOWN;
if (tas_write_reg(tas, TAS_REG_ACR, 1, &tas->acr))
- return -ENODEV;
+ goto outerr;
return 0;
+ outerr:
+ return -ENODEV;
}
static int tas_switch_clock(struct codec_info_item *cii, enum clock_switch clock)
@@ -666,11 +724,13 @@ static int tas_switch_clock(struct codec
break;
case CLOCK_SWITCH_SLAVE:
/* Clocks are back, re-init the codec */
+ mutex_lock(&tas->mtx);
tas_reset_init(tas);
tas_set_volume(tas);
tas_set_mixer(tas);
tas->hw_enabled = 1;
tas->codec.gpio->methods->all_amps_restore(tas->codec.gpio);
+ mutex_unlock(&tas->mtx);
break;
default:
/* doesn't happen as of now */
@@ -684,19 +744,23 @@ static int tas_switch_clock(struct codec
* our i2c device is suspended, and then take note of that! */
static int tas_suspend(struct tas *tas)
{
+ mutex_lock(&tas->mtx);
tas->hw_enabled = 0;
tas->acr |= TAS_ACR_ANALOG_PDOWN;
tas_write_reg(tas, TAS_REG_ACR, 1, &tas->acr);
+ mutex_unlock(&tas->mtx);
return 0;
}
static int tas_resume(struct tas *tas)
{
/* reset codec */
+ mutex_lock(&tas->mtx);
tas_reset_init(tas);
tas_set_volume(tas);
tas_set_mixer(tas);
tas->hw_enabled = 1;
+ mutex_unlock(&tas->mtx);
return 0;
}
@@ -739,11 +803,14 @@ static int tas_init_codec(struct aoa_cod
return -EINVAL;
}
+ mutex_lock(&tas->mtx);
if (tas_reset_init(tas)) {
printk(KERN_ERR PFX "tas failed to initialise\n");
+ mutex_unlock(&tas->mtx);
return -ENXIO;
}
tas->hw_enabled = 1;
+ mutex_unlock(&tas->mtx);
if (tas->codec.soundbus_dev->attach_codec(tas->codec.soundbus_dev,
aoa_get_card(),
@@ -822,6 +889,7 @@ static int tas_create(struct i2c_adapter
if (!tas)
return -ENOMEM;
+ mutex_init(&tas->mtx);
tas->i2c.driver = &tas_driver;
tas->i2c.adapter = adapter;
tas->i2c.addr = addr;
@@ -850,6 +918,7 @@ static int tas_create(struct i2c_adapter
detach:
i2c_detach_client(&tas->i2c);
fail:
+ mutex_destroy(&tas->mtx);
kfree(tas);
return -EINVAL;
}
@@ -908,6 +977,7 @@ static int tas_i2c_detach(struct i2c_cli
/* power down codec chip */
tas_write_reg(tas, TAS_REG_ACR, 1, &tmp);
+ mutex_destroy(&tas->mtx);
kfree(tas);
return 0;
}
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