[ALSA] make control.c suspend aware

Modules: Control Midlevel

This patch prevents user-space apps from accessing the hardware via
control interface while the soundcard is suspended.

Signed-off-by: Giuliano Pochini <pochini@shiny.it>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/core/control.c b/sound/core/control.c
index 0c29679..9742bdb 100644 (file)
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -658,7 +658,11 @@ static int snd_ctl_elem_info_user(struct snd_ctl_file *ctl,
 
        if (copy_from_user(&info, _info, sizeof(info)))
                return -EFAULT;
-       result = snd_ctl_elem_info(ctl, &info);
+       snd_power_lock(ctl->card);
+       result = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0, NULL);
+       if (result >= 0)
+               result = snd_ctl_elem_info(ctl, &info);
+       snd_power_unlock(ctl->card);
        if (result >= 0)
                if (copy_to_user(_info, &info, sizeof(info)))
                        return -EFAULT;
@@ -708,7 +712,11 @@ static int snd_ctl_elem_read_user(struct snd_card *card,
                kfree(control);
                return -EFAULT;
        }
-       result = snd_ctl_elem_read(card, control);
+       snd_power_lock(card);
+       result = snd_power_wait(card, SNDRV_CTL_POWER_D0, NULL);
+       if (result >= 0)
+               result = snd_ctl_elem_read(card, control);
+       snd_power_unlock(card);
        if (result >= 0)
                if (copy_to_user(_control, control, sizeof(*control)))
                        result = -EFAULT;
@@ -758,6 +766,7 @@ static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
                                   struct snd_ctl_elem_value __user *_control)
 {
        struct snd_ctl_elem_value *control;
+       struct snd_card *card;
        int result;
 
        control = kmalloc(sizeof(*control), GFP_KERNEL);
@@ -767,7 +776,12 @@ static int snd_ctl_elem_write_user(struct snd_ctl_file *file,
                kfree(control);
                return -EFAULT;
        }
-       result = snd_ctl_elem_write(file->card, file, control);
+       card = file->card;
+       snd_power_lock(card);
+       result = snd_power_wait(card, SNDRV_CTL_POWER_D0, NULL);
+       if (result >= 0)
+               result = snd_ctl_elem_write(card, file, control);
+       snd_power_unlock(card);
        if (result >= 0)
                if (copy_to_user(_control, control, sizeof(*control)))
                        result = -EFAULT;

diff --git a/sound/core/control_compat.c b/sound/core/control_compat.c
index a529b62..84fef50 100644 (file)
--- a/sound/core/control_compat.c
+++ b/sound/core/control_compat.c
@@ -107,7 +107,13 @@ static int snd_ctl_elem_info_compat(struct snd_ctl_file *ctl,
         */
        if (get_user(data->value.enumerated.item, &data32->value.enumerated.item))
                goto error;
-       err = snd_ctl_elem_info(ctl, data);
+
+       snd_power_lock(ctl->card);
+       err = snd_power_wait(ctl->card, SNDRV_CTL_POWER_D0, NULL);
+       if (err >= 0)
+               err = snd_ctl_elem_info(ctl, data);
+       snd_power_unlock(ctl->card);
+
        if (err < 0)
                goto error;
        /* restore info to 32bit */
@@ -286,9 +292,14 @@ static int snd_ctl_elem_read_user_compat(struct snd_card *card,
 
        if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
                goto error;
-       if ((err = snd_ctl_elem_read(card, data)) < 0)
-               goto error;
-       err = copy_ctl_value_to_user(data32, data, type, count);
+
+       snd_power_lock(card);
+       err = snd_power_wait(card, SNDRV_CTL_POWER_D0, NULL);
+       if (err >= 0)
+               err = snd_ctl_elem_read(card, data);
+       snd_power_unlock(card);
+       if (err >= 0)
+               err = copy_ctl_value_to_user(data32, data, type, count);
  error:
        kfree(data);
        return err;
@@ -298,17 +309,23 @@ static int snd_ctl_elem_write_user_compat(struct snd_ctl_file *file,
                                          struct snd_ctl_elem_value32 __user *data32)
 {
        struct snd_ctl_elem_value *data;
+       struct snd_card *card = file->card;
        int err, type, count;
 
        data = kzalloc(sizeof(*data), GFP_KERNEL);
        if (data == NULL)
                return -ENOMEM;
 
-       if ((err = copy_ctl_value_from_user(file->card, data, data32, &type, &count)) < 0)
-               goto error;
-       if ((err = snd_ctl_elem_write(file->card, file, data)) < 0)
+       if ((err = copy_ctl_value_from_user(card, data, data32, &type, &count)) < 0)
                goto error;
-       err = copy_ctl_value_to_user(data32, data, type, count);
+
+       snd_power_lock(card);
+       err = snd_power_wait(card, SNDRV_CTL_POWER_D0, NULL);
+       if (err >= 0)
+               err = snd_ctl_elem_write(card, file, data);
+       snd_power_unlock(card);
+       if (err >= 0)
+               err = copy_ctl_value_to_user(data32, data, type, count);
  error:
        kfree(data);
        return err;