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authorPawel MOLL <pawel.moll@st.com>2008-07-29 17:34:26 +0100
committerJaroslav Kysela <perex@perex.cz>2008-07-29 21:32:48 +0200
commit9423969005586e6e27ca380e01b4a8c50698e2af (patch)
tree818bef3892109c05a4ad5ec3ae5e90dd4436c0c6 /sound/core/pcm.c
parent815ecf8dec95d07e260a16ebe8409f4b7c0fdc0f (diff)
ALSA: Fix limit of 8 PCM devices in SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE
When compiled with CONFIG_SND_DYNAMIC_MINORS the ALSA core is fine to have more than 8 PCM devices per card, except one place - the SNDRV_CTL_IOCTL_PCM_NEXT_DEVICE ioctl, which will not enumerate devices > 7. This patch fixes the issue, changing the devices list organisation. Instead of adding new device to the tail, the list is now kept always ordered (by card number, then device number). Thus, during enumeration, it is easy to discover the fact that there is no more given card's devices. The same limit was present in OSS emulation code. It has been fixed as well. Additionally the device field of struct snd_pcm is now int, instead of unsigned int, as there is no obvious reason for keeping it unsigned. This caused a lot of problems with comparing this value with other (almost always signed) variables. There is just one more place where device number is unsigned - in struct snd_pcm_info, which should be also sorted out in future. Signed-off-by: Pawel MOLL <pawel.moll@st.com> Signed-off-by: Jaroslav Kysela <perex@perex.cz>
Diffstat (limited to 'sound/core/pcm.c')
-rw-r--r--sound/core/pcm.c50
1 files changed, 37 insertions, 13 deletions
diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index ece25c718e9..24271a3bd90 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -42,7 +42,7 @@ static int snd_pcm_dev_free(struct snd_device *device);
static int snd_pcm_dev_register(struct snd_device *device);
static int snd_pcm_dev_disconnect(struct snd_device *device);
-static struct snd_pcm *snd_pcm_search(struct snd_card *card, int device)
+static inline struct snd_pcm *snd_pcm_get(struct snd_card *card, int device)
{
struct snd_pcm *pcm;
@@ -53,6 +53,37 @@ static struct snd_pcm *snd_pcm_search(struct snd_card *card, int device)
return NULL;
}
+static inline int snd_pcm_next(struct snd_card *card, int device)
+{
+ struct snd_pcm *pcm;
+
+ list_for_each_entry(pcm, &snd_pcm_devices, list) {
+ if (pcm->card == card && pcm->device > device)
+ return pcm->device;
+ else if (pcm->card->number > card->number)
+ return -1;
+ }
+ return -1;
+}
+
+static inline int snd_pcm_add(struct snd_pcm *newpcm)
+{
+ struct snd_pcm *pcm;
+
+ list_for_each_entry(pcm, &snd_pcm_devices, list) {
+ if (pcm->card == newpcm->card && pcm->device == newpcm->device)
+ return -EBUSY;
+ if (pcm->card->number > newpcm->card->number ||
+ (pcm->card == newpcm->card &&
+ pcm->device > newpcm->device)) {
+ list_add(&newpcm->list, pcm->list.prev);
+ return 0;
+ }
+ }
+ list_add_tail(&newpcm->list, &snd_pcm_devices);
+ return 0;
+}
+
static int snd_pcm_control_ioctl(struct snd_card *card,
struct snd_ctl_file *control,
unsigned int cmd, unsigned long arg)
@@ -65,14 +96,7 @@ static int snd_pcm_control_ioctl(struct snd_card *card,
if (get_user(device, (int __user *)arg))
return -EFAULT;
mutex_lock(&register_mutex);
- device = device < 0 ? 0 : device + 1;
- while (device < SNDRV_PCM_DEVICES) {
- if (snd_pcm_search(card, device))
- break;
- device++;
- }
- if (device == SNDRV_PCM_DEVICES)
- device = -1;
+ device = snd_pcm_next(card, device);
mutex_unlock(&register_mutex);
if (put_user(device, (int __user *)arg))
return -EFAULT;
@@ -98,7 +122,7 @@ static int snd_pcm_control_ioctl(struct snd_card *card,
if (get_user(subdevice, &info->subdevice))
return -EFAULT;
mutex_lock(&register_mutex);
- pcm = snd_pcm_search(card, device);
+ pcm = snd_pcm_get(card, device);
if (pcm == NULL) {
err = -ENXIO;
goto _error;
@@ -931,11 +955,11 @@ static int snd_pcm_dev_register(struct snd_device *device)
snd_assert(pcm != NULL && device != NULL, return -ENXIO);
mutex_lock(&register_mutex);
- if (snd_pcm_search(pcm->card, pcm->device)) {
+ err = snd_pcm_add(pcm);
+ if (err) {
mutex_unlock(&register_mutex);
- return -EBUSY;
+ return err;
}
- list_add_tail(&pcm->list, &snd_pcm_devices);
for (cidx = 0; cidx < 2; cidx++) {
int devtype = -1;
if (pcm->streams[cidx].substream == NULL)