linux/include/sound/soc-card.h
Richard Fitzgerald eba2eb2495
ASoC: soc-card: Fix missing locking in snd_soc_card_get_kcontrol()
snd_soc_card_get_kcontrol() must be holding a read lock on
card->controls_rwsem while walking the controls list.

Compare with snd_ctl_find_numid().

The existing function is renamed snd_soc_card_get_kcontrol_locked()
so that it can be called from contexts that are already holding
card->controls_rwsem (for example, control get/put functions).

There are few direct or indirect callers of
snd_soc_card_get_kcontrol(), and most are safe. Three require
changes, which have been included in this patch:

codecs/cs35l45.c:
  cs35l45_activate_ctl() is called from a control put() function so
  is changed to call snd_soc_card_get_kcontrol_locked().

codecs/cs35l56.c:
  cs35l56_sync_asp1_mixer_widgets_with_firmware() is called from
  control get()/put() functions so is changed to call
  snd_soc_card_get_kcontrol_locked().

fsl/fsl_xcvr.c:
  fsl_xcvr_activate_ctl() is called from three places, one of which
  already holds card->controls_rwsem:
  1. fsl_xcvr_mode_put(), a control put function, which will
     already be holding card->controls_rwsem.
  2. fsl_xcvr_startup(), a DAI startup function.
  3. fsl_xcvr_shutdown(), a DAI shutdown function.

  To fix this, fsl_xcvr_activate_ctl() has been changed to call
  snd_soc_card_get_kcontrol_locked() so that it is safe to call
  directly from fsl_xcvr_mode_put().
  The fsl_xcvr_startup() and fsl_xcvr_shutdown() functions have been
  changed to take a read lock on card->controls_rsem() around calls
  to fsl_xcvr_activate_ctl(). While this is not very elegant, it
  keeps the change small, to avoid this patch creating a large
  collateral churn in fsl/fsl_xcvr.c.

Analysis of other callers of snd_soc_card_get_kcontrol() is that
they do not need any changes, they are not holding card->controls_rwsem
when they call snd_soc_card_get_kcontrol().

Direct callers of snd_soc_card_get_kcontrol():
  fsl/fsl_spdif.c: fsl_spdif_dai_probe() - DAI probe function
  fsl/fsl_micfil.c: voice_detected_fn() - IRQ handler

Indirect callers via soc_component_notify_control():
  codecs/cs42l43: cs42l43_mic_shutter() - IRQ handler
  codecs/cs42l43: cs42l43_spk_shutter() - IRQ handler
  codecs/ak4118.c: ak4118_irq_handler() - IRQ handler
  codecs/wm_adsp.c: wm_adsp_write_ctl() - not currently used

Indirect callers via snd_soc_limit_volume():
  qcom/sc8280xp.c: sc8280xp_snd_init() - DAIlink init function
  ti/rx51.c: rx51_aic34_init() - DAI init function

I don't have hardware to test the fsl/*, qcom/sc828xp.c, ti/rx51.c
and ak4118.c changes.

Backport note:
The fsl/, qcom/, cs35l45, cs35l56 and cs42l43 callers were added
since the Fixes commit so won't all be present on older kernels.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Fixes: 209c6cdfd2 ("ASoC: soc-card: move snd_soc_card_get_kcontrol() to soc-card")
Link: https://lore.kernel.org/r/20240221123710.690224-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-02-23 13:40:06 +00:00

128 lines
3.6 KiB
C

/* SPDX-License-Identifier: GPL-2.0
*
* soc-card.h
*
* Copyright (C) 2019 Renesas Electronics Corp.
* Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
*/
#ifndef __SOC_CARD_H
#define __SOC_CARD_H
enum snd_soc_card_subclass {
SND_SOC_CARD_CLASS_ROOT = 0,
SND_SOC_CARD_CLASS_RUNTIME = 1,
};
static inline void snd_soc_card_mutex_lock_root(struct snd_soc_card *card)
{
mutex_lock_nested(&card->mutex, SND_SOC_CARD_CLASS_ROOT);
}
static inline void snd_soc_card_mutex_lock(struct snd_soc_card *card)
{
mutex_lock_nested(&card->mutex, SND_SOC_CARD_CLASS_RUNTIME);
}
static inline void snd_soc_card_mutex_unlock(struct snd_soc_card *card)
{
mutex_unlock(&card->mutex);
}
struct snd_kcontrol *snd_soc_card_get_kcontrol(struct snd_soc_card *soc_card,
const char *name);
struct snd_kcontrol *snd_soc_card_get_kcontrol_locked(struct snd_soc_card *soc_card,
const char *name);
int snd_soc_card_jack_new(struct snd_soc_card *card, const char *id, int type,
struct snd_soc_jack *jack);
int snd_soc_card_jack_new_pins(struct snd_soc_card *card, const char *id,
int type, struct snd_soc_jack *jack,
struct snd_soc_jack_pin *pins,
unsigned int num_pins);
int snd_soc_card_suspend_pre(struct snd_soc_card *card);
int snd_soc_card_suspend_post(struct snd_soc_card *card);
int snd_soc_card_resume_pre(struct snd_soc_card *card);
int snd_soc_card_resume_post(struct snd_soc_card *card);
int snd_soc_card_probe(struct snd_soc_card *card);
int snd_soc_card_late_probe(struct snd_soc_card *card);
void snd_soc_card_fixup_controls(struct snd_soc_card *card);
int snd_soc_card_remove(struct snd_soc_card *card);
int snd_soc_card_set_bias_level(struct snd_soc_card *card,
struct snd_soc_dapm_context *dapm,
enum snd_soc_bias_level level);
int snd_soc_card_set_bias_level_post(struct snd_soc_card *card,
struct snd_soc_dapm_context *dapm,
enum snd_soc_bias_level level);
int snd_soc_card_add_dai_link(struct snd_soc_card *card,
struct snd_soc_dai_link *dai_link);
void snd_soc_card_remove_dai_link(struct snd_soc_card *card,
struct snd_soc_dai_link *dai_link);
#ifdef CONFIG_PCI
static inline void snd_soc_card_set_pci_ssid(struct snd_soc_card *card,
unsigned short vendor,
unsigned short device)
{
card->pci_subsystem_vendor = vendor;
card->pci_subsystem_device = device;
card->pci_subsystem_set = true;
}
static inline int snd_soc_card_get_pci_ssid(struct snd_soc_card *card,
unsigned short *vendor,
unsigned short *device)
{
if (!card->pci_subsystem_set)
return -ENOENT;
*vendor = card->pci_subsystem_vendor;
*device = card->pci_subsystem_device;
return 0;
}
#else /* !CONFIG_PCI */
static inline void snd_soc_card_set_pci_ssid(struct snd_soc_card *card,
unsigned short vendor,
unsigned short device)
{
}
static inline int snd_soc_card_get_pci_ssid(struct snd_soc_card *card,
unsigned short *vendor,
unsigned short *device)
{
return -ENOENT;
}
#endif /* CONFIG_PCI */
/* device driver data */
static inline void snd_soc_card_set_drvdata(struct snd_soc_card *card,
void *data)
{
card->drvdata = data;
}
static inline void *snd_soc_card_get_drvdata(struct snd_soc_card *card)
{
return card->drvdata;
}
static inline
struct snd_soc_dai *snd_soc_card_get_codec_dai(struct snd_soc_card *card,
const char *dai_name)
{
struct snd_soc_pcm_runtime *rtd;
for_each_card_rtds(card, rtd) {
if (!strcmp(snd_soc_rtd_to_codec(rtd, 0)->name, dai_name))
return snd_soc_rtd_to_codec(rtd, 0);
}
return NULL;
}
#endif /* __SOC_CARD_H */