diff options
author | Eldad Zack <eldad@fogrefinery.com> | 2013-04-03 23:18:55 +0200 |
---|---|---|
committer | Takashi Iwai <tiwai@suse.de> | 2013-04-04 08:31:14 +0200 |
commit | 8c55af3f69be6021631628b968cad301d3f294c8 (patch) | |
tree | 049cd4e6cc4aa6c5fb7143d719fecee2f6c93025 /sound/usb/clock.c | |
parent | ALSA: usb-audio: UAC2: do clock validity check earlier (diff) | |
download | linux-8c55af3f69be6021631628b968cad301d3f294c8.tar.xz linux-8c55af3f69be6021631628b968cad301d3f294c8.zip |
ALSA: usb-audio: UAC2: try to find and switch to valid clock
If a selector is available on a device, it may be pointing to a
clock source which is currently invalid.
If there is a valid clock source which can be selected, switch
to it.
Signed-off-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/clock.c')
-rw-r--r-- | sound/usb/clock.c | 69 |
1 files changed, 66 insertions, 3 deletions
diff --git a/sound/usb/clock.c b/sound/usb/clock.c index 0c98f52a1c9c..d7ab2d75aefd 100644 --- a/sound/usb/clock.c +++ b/sound/usb/clock.c @@ -99,6 +99,41 @@ static int uac_clock_selector_get_val(struct snd_usb_audio *chip, int selector_i return buf; } +static int uac_clock_selector_set_val(struct snd_usb_audio *chip, int selector_id, + unsigned char pin) +{ + int ret; + + ret = snd_usb_ctl_msg(chip->dev, usb_sndctrlpipe(chip->dev, 0), + UAC2_CS_CUR, + USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_OUT, + UAC2_CX_CLOCK_SELECTOR << 8, + snd_usb_ctrl_intf(chip) | (selector_id << 8), + &pin, sizeof(pin)); + if (ret < 0) + return ret; + + if (ret != sizeof(pin)) { + snd_printk(KERN_ERR + "usb-audio:%d: setting selector (id %d) unexpected length %d\n", + chip->dev->devnum, selector_id, ret); + return -EINVAL; + } + + ret = uac_clock_selector_get_val(chip, selector_id); + if (ret < 0) + return ret; + + if (ret != pin) { + snd_printk(KERN_ERR + "usb-audio:%d: setting selector (id %d) to %x failed (current: %d)\n", + chip->dev->devnum, selector_id, pin, ret); + return -EINVAL; + } + + return ret; +} + static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id) { int err; @@ -161,7 +196,7 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id); if (selector) { - int ret; + int ret, i, cur; /* the entity ID we are looking for is a selector. * find out what it currently selects */ @@ -179,8 +214,35 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, return -EINVAL; } - return __uac_clock_find_source(chip, selector->baCSourceID[ret-1], + cur = ret; + ret = __uac_clock_find_source(chip, selector->baCSourceID[ret - 1], visited, validate); + if (!validate || ret > 0) + return ret; + + /* The current clock source is invalid, try others. */ + for (i = 1; i <= selector->bNrInPins; i++) { + int err; + + if (i == cur) + continue; + + ret = __uac_clock_find_source(chip, selector->baCSourceID[i - 1], + visited, true); + if (ret < 0) + continue; + + err = uac_clock_selector_set_val(chip, entity_id, i); + if (err < 0) + continue; + + snd_printk(KERN_INFO + "usb-audio:%d: found and selected valid clock source %d\n", + chip->dev->devnum, ret); + return ret; + } + + return -ENXIO; } /* FIXME: multipliers only act as pass-thru element for now */ @@ -284,8 +346,9 @@ static int set_sample_rate_v2(struct snd_usb_audio *chip, int iface, struct usb_device *dev = chip->dev; __le32 data; int err, cur_rate, prev_rate; - int clock = snd_usb_clock_find_source(chip, fmt->clock, true); + int clock; + clock = snd_usb_clock_find_source(chip, fmt->clock, true); if (clock < 0) return clock; |