sound/pci/lola/lola_clock.c
Source file repositories/reference/linux-study-clean/sound/pci/lola/lola_clock.c
File Facts
- System
- Linux kernel
- Corpus path
sound/pci/lola/lola_clock.c- Extension
.c- Size
- 7540 bytes
- Lines
- 311
- Domain
- Driver Families
- Bucket
- sound/pci
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/kernel.hlinux/init.hlinux/delay.hsound/core.hsound/pcm.hlola.h
Detected Declarations
function Copyrightfunction check_gran_clock_compatibilityfunction lola_set_granularityfunction lola_init_clock_widgetfunction lola_enable_clock_eventsfunction lola_set_clock_indexfunction lola_update_ext_clock_freqfunction lola_set_clockfunction lola_set_sample_rate
Annotated Snippet
if (err < 0) {
dev_err(chip->card->dev, "Can't read CLOCK_LIST\n");
return -EINVAL;
}
items[0] = val & 0xfff;
items[1] = (val >> 16) & 0xfff;
items[2] = res_ex & 0xfff;
items[3] = (res_ex >> 16) & 0xfff;
for (j = 0; j < 4; j++) {
unsigned char type = items[j] >> 8;
unsigned int freq = items[j] & 0xff;
int format = LOLA_CLOCK_FORMAT_NONE;
bool add_clock = true;
if (type == LOLA_CLOCK_TYPE_INTERNAL) {
freq = lola_sample_rate_convert(freq);
if (freq < chip->sample_rate_min)
add_clock = false;
else if (freq == 48000) {
chip->clock.cur_index = idx_list;
chip->clock.cur_freq = 48000;
chip->clock.cur_valid = true;
}
} else if (type == LOLA_CLOCK_TYPE_VIDEO) {
freq = lola_sample_rate_convert(freq);
if (freq < chip->sample_rate_min)
add_clock = false;
/* video clock has a format (0:NTSC, 1:PAL)*/
if (items[j] & 0x80)
format = LOLA_CLOCK_FORMAT_NTSC;
else
format = LOLA_CLOCK_FORMAT_PAL;
}
if (add_clock) {
struct lola_sample_clock *sc;
sc = &chip->clock.sample_clock[idx_list];
sc->type = type;
sc->format = format;
sc->freq = freq;
/* keep the index used with the board */
chip->clock.idx_lookup[idx_list] = idx;
idx_list++;
} else {
chip->clock.items--;
}
if (++idx >= nitems)
break;
}
}
return 0;
}
/* enable unsolicited events of the clock widget */
int lola_enable_clock_events(struct lola *chip)
{
unsigned int res;
int err;
err = lola_codec_read(chip, chip->clock.nid,
LOLA_VERB_SET_UNSOLICITED_ENABLE,
LOLA_UNSOLICITED_ENABLE | LOLA_UNSOLICITED_TAG,
0, &res, NULL);
if (err < 0)
return err;
if (res) {
dev_warn(chip->card->dev, "error in enable_clock_events %d\n",
res);
return -EINVAL;
}
return 0;
}
int lola_set_clock_index(struct lola *chip, unsigned int idx)
{
unsigned int res;
int err;
err = lola_codec_read(chip, chip->clock.nid,
LOLA_VERB_SET_CLOCK_SELECT,
chip->clock.idx_lookup[idx],
0, &res, NULL);
if (err < 0)
return err;
if (res) {
dev_warn(chip->card->dev, "error in set_clock %d\n", res);
return -EINVAL;
}
return 0;
}
Annotation
- Immediate include surface: `linux/kernel.h`, `linux/init.h`, `linux/delay.h`, `sound/core.h`, `sound/pcm.h`, `lola.h`.
- Detected declarations: `function Copyright`, `function check_gran_clock_compatibility`, `function lola_set_granularity`, `function lola_init_clock_widget`, `function lola_enable_clock_events`, `function lola_set_clock_index`, `function lola_update_ext_clock_freq`, `function lola_set_clock`, `function lola_set_sample_rate`.
- Atlas domain: Driver Families / sound/pci.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.