From 06ffc1ebddbed88662a47646ff6aa6a2b41f0aec Mon Sep 17 00:00:00 2001 From: Eldad Zack Date: Wed, 3 Apr 2013 23:18:54 +0200 Subject: ALSA: usb-audio: UAC2: do clock validity check earlier Move the check that parse_audio_format_rates_v2() do after receiving the clock source entity ID directly into the find function and add a validation flag to the function. This patch does not introduce any logic flow change. It is provided to allow introducing automatic clock switching easier later. By moving this uac_clock_source_is_valid callsite, 2 additional callsites can be avoided. Signed-off-by: Eldad Zack Signed-off-by: Takashi Iwai --- sound/usb/clock.c | 34 ++++++++++++++++++---------------- 1 file changed, 18 insertions(+), 16 deletions(-) (limited to 'sound/usb/clock.c') diff --git a/sound/usb/clock.c b/sound/usb/clock.c index 013b346f045d..0c98f52a1c9c 100644 --- a/sound/usb/clock.c +++ b/sound/usb/clock.c @@ -131,7 +131,8 @@ static bool uac_clock_source_is_valid(struct snd_usb_audio *chip, int source_id) } static int __uac_clock_find_source(struct snd_usb_audio *chip, - int entity_id, unsigned long *visited) + int entity_id, unsigned long *visited, + bool validate) { struct uac_clock_source_descriptor *source; struct uac_clock_selector_descriptor *selector; @@ -148,8 +149,15 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, /* first, see if the ID we're looking for is a clock source already */ source = snd_usb_find_clock_source(chip->ctrl_intf, entity_id); - if (source) - return source->bClockID; + if (source) { + entity_id = source->bClockID; + if (validate && !uac_clock_source_is_valid(chip, entity_id)) { + snd_printk(KERN_ERR "usb-audio:%d: clock source %d is not valid, cannot use\n", + chip->dev->devnum, entity_id); + return -ENXIO; + } + return entity_id; + } selector = snd_usb_find_clock_selector(chip->ctrl_intf, entity_id); if (selector) { @@ -164,7 +172,7 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, /* Selector values are one-based */ if (ret > selector->bNrInPins || ret < 1) { - printk(KERN_ERR + snd_printk(KERN_ERR "%s(): selector reported illegal value, id %d, ret %d\n", __func__, selector->bClockID, ret); @@ -172,14 +180,14 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, } return __uac_clock_find_source(chip, selector->baCSourceID[ret-1], - visited); + visited, validate); } /* FIXME: multipliers only act as pass-thru element for now */ multiplier = snd_usb_find_clock_multiplier(chip->ctrl_intf, entity_id); if (multiplier) return __uac_clock_find_source(chip, multiplier->bCSourceID, - visited); + visited, validate); return -EINVAL; } @@ -195,11 +203,12 @@ static int __uac_clock_find_source(struct snd_usb_audio *chip, * * Returns the clock source UnitID (>=0) on success, or an error. */ -int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id) +int snd_usb_clock_find_source(struct snd_usb_audio *chip, int entity_id, + bool validate) { DECLARE_BITMAP(visited, 256); memset(visited, 0, sizeof(visited)); - return __uac_clock_find_source(chip, entity_id, visited); + return __uac_clock_find_source(chip, entity_id, visited, validate); } static int set_sample_rate_v1(struct snd_usb_audio *chip, int iface, @@ -275,18 +284,11 @@ 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); + int clock = snd_usb_clock_find_source(chip, fmt->clock, true); if (clock < 0) return clock; - if (!uac_clock_source_is_valid(chip, clock)) { - /* TODO: should we try to find valid clock setups by ourself? */ - snd_printk(KERN_ERR "%d:%d:%d: clock source %d is not valid, cannot use\n", - dev->devnum, iface, fmt->altsetting, clock); - return -ENXIO; - } - prev_rate = get_sample_rate_v2(chip, iface, fmt->altsetting, clock); data = cpu_to_le32(rate); -- cgit v1.2.3