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WSL2-Linux-Kernel/include/sound/hda_regmap.h

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ALSA: hda - Add regmap support This patch adds an infrastructure to support regmap-based verb accesses. Because o the asymmetric nature of HD-audio verbs, especially the amp verbs, we need to translate the verbs as a sort of pseudo registers to be mapped uniquely in regmap. In this patch, a pseudo register is built from the NID, the AC_VERB_GET_* and 8bit parameters, i.e. almost in the form to be sent to HD-audio bus but without codec address field. OTOH, for writing, the same pseudo register is translated to AC_VERB_SET_* automatically. The AC_VERB_SET_AMP_* verb is re-encoded from the corresponding AC_VERB_GET_AMP_* verb and parameter at writing. Some verbs has a single command for read but multiple for writes. A write for such a verb is split automatically to multiple verbs. The patch provides also a few handy helper functions. They are designed to be accessible even without regmap. When no regmap is set up (e.g. before the codec device instantiation), the direct hardware access is used. Also, it tries to avoid the unnecessary power-up. The power up/down sequence is performed only on demand. The codec driver needs to call snd_hdac_regmap_exit() and snd_hdac_regmap_exit() at probe and remove if it wants the regmap access. There is one flag added to hdac_device. When the flag lazy_cache is set, regmap helper ignores a write for a suspended device and returns as if it was actually written. It reduces the hardware access pretty much, e.g. when adjusting the mixer volume while in idle. This assumes that the driver will sync the cache later at resume properly, so use it carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-25 16:42:38 +03:00
/*
* HD-audio regmap helpers
*/
#ifndef __SOUND_HDA_REGMAP_H
#define __SOUND_HDA_REGMAP_H
#include <linux/regmap.h>
#include <sound/core.h>
#include <sound/hdaudio.h>
ALSA: hda - Re-add the lost fake mute support Yet another regression by the transition to regmap cache; for better usability, we had the fake mute control using the zero amp value for Conexant codecs, and this was forgotten in the new hda core code. Since the bits 4-7 are unused for the amp registers (as we follow the syntax of AMP_GET verb), the bit 4 is now used to indicate the fake mute. For setting this flag, snd_hda_codec_amp_update() becomes a function from a simple macro. The bonus is that it gained a proper function description. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-06-11 11:51:28 +03:00
#define AC_AMP_FAKE_MUTE 0x10 /* fake mute bit set to amp verbs */
ALSA: hda - Add regmap support This patch adds an infrastructure to support regmap-based verb accesses. Because o the asymmetric nature of HD-audio verbs, especially the amp verbs, we need to translate the verbs as a sort of pseudo registers to be mapped uniquely in regmap. In this patch, a pseudo register is built from the NID, the AC_VERB_GET_* and 8bit parameters, i.e. almost in the form to be sent to HD-audio bus but without codec address field. OTOH, for writing, the same pseudo register is translated to AC_VERB_SET_* automatically. The AC_VERB_SET_AMP_* verb is re-encoded from the corresponding AC_VERB_GET_AMP_* verb and parameter at writing. Some verbs has a single command for read but multiple for writes. A write for such a verb is split automatically to multiple verbs. The patch provides also a few handy helper functions. They are designed to be accessible even without regmap. When no regmap is set up (e.g. before the codec device instantiation), the direct hardware access is used. Also, it tries to avoid the unnecessary power-up. The power up/down sequence is performed only on demand. The codec driver needs to call snd_hdac_regmap_exit() and snd_hdac_regmap_exit() at probe and remove if it wants the regmap access. There is one flag added to hdac_device. When the flag lazy_cache is set, regmap helper ignores a write for a suspended device and returns as if it was actually written. It reduces the hardware access pretty much, e.g. when adjusting the mixer volume while in idle. This assumes that the driver will sync the cache later at resume properly, so use it carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-25 16:42:38 +03:00
int snd_hdac_regmap_init(struct hdac_device *codec);
void snd_hdac_regmap_exit(struct hdac_device *codec);
ALSA: hda - Allow driver to add vendor-specific verbs for regmap Codecs may have own vendor-specific verbs, and we need to allow each driver to give such verbs for cached accesses. Here a verb can be put into a single array and looked through it at readable and writeable callbacks. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-26 14:29:03 +03:00
int snd_hdac_regmap_add_vendor_verb(struct hdac_device *codec,
unsigned int verb);
ALSA: hda - Add regmap support This patch adds an infrastructure to support regmap-based verb accesses. Because o the asymmetric nature of HD-audio verbs, especially the amp verbs, we need to translate the verbs as a sort of pseudo registers to be mapped uniquely in regmap. In this patch, a pseudo register is built from the NID, the AC_VERB_GET_* and 8bit parameters, i.e. almost in the form to be sent to HD-audio bus but without codec address field. OTOH, for writing, the same pseudo register is translated to AC_VERB_SET_* automatically. The AC_VERB_SET_AMP_* verb is re-encoded from the corresponding AC_VERB_GET_AMP_* verb and parameter at writing. Some verbs has a single command for read but multiple for writes. A write for such a verb is split automatically to multiple verbs. The patch provides also a few handy helper functions. They are designed to be accessible even without regmap. When no regmap is set up (e.g. before the codec device instantiation), the direct hardware access is used. Also, it tries to avoid the unnecessary power-up. The power up/down sequence is performed only on demand. The codec driver needs to call snd_hdac_regmap_exit() and snd_hdac_regmap_exit() at probe and remove if it wants the regmap access. There is one flag added to hdac_device. When the flag lazy_cache is set, regmap helper ignores a write for a suspended device and returns as if it was actually written. It reduces the hardware access pretty much, e.g. when adjusting the mixer volume while in idle. This assumes that the driver will sync the cache later at resume properly, so use it carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-25 16:42:38 +03:00
int snd_hdac_regmap_read_raw(struct hdac_device *codec, unsigned int reg,
unsigned int *val);
ALSA: hda - Fix possible race on regmap bypass flip HD-audio driver uses regmap cache bypass feature for reading a raw value without the cache. But this is racy since both the cached and the uncached reads may occur concurrently. The former is done via the normal control API access while the latter comes from the proc file read. Even though the regmap itself has the protection against the concurrent accesses, the flag set/reset is done without the protection, so it may lead to inconsistent state of bypass flag that doesn't match with the current read and occasionally result in a kernel WARNING like: WARNING: CPU: 3 PID: 2731 at drivers/base/regmap/regcache.c:499 regcache_cache_only+0x78/0x93 One way to work around such a problem is to wrap with a mutex. But in this case, the solution is simpler: for the uncached read, we just skip the regmap and directly calls its accessor. The verb execution there is protected by itself, so basically it's safe to call individually. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=116171 Signed-off-by: Takashi Iwai <tiwai@suse.de>
2016-04-21 18:49:11 +03:00
int snd_hdac_regmap_read_raw_uncached(struct hdac_device *codec,
unsigned int reg, unsigned int *val);
ALSA: hda - Add regmap support This patch adds an infrastructure to support regmap-based verb accesses. Because o the asymmetric nature of HD-audio verbs, especially the amp verbs, we need to translate the verbs as a sort of pseudo registers to be mapped uniquely in regmap. In this patch, a pseudo register is built from the NID, the AC_VERB_GET_* and 8bit parameters, i.e. almost in the form to be sent to HD-audio bus but without codec address field. OTOH, for writing, the same pseudo register is translated to AC_VERB_SET_* automatically. The AC_VERB_SET_AMP_* verb is re-encoded from the corresponding AC_VERB_GET_AMP_* verb and parameter at writing. Some verbs has a single command for read but multiple for writes. A write for such a verb is split automatically to multiple verbs. The patch provides also a few handy helper functions. They are designed to be accessible even without regmap. When no regmap is set up (e.g. before the codec device instantiation), the direct hardware access is used. Also, it tries to avoid the unnecessary power-up. The power up/down sequence is performed only on demand. The codec driver needs to call snd_hdac_regmap_exit() and snd_hdac_regmap_exit() at probe and remove if it wants the regmap access. There is one flag added to hdac_device. When the flag lazy_cache is set, regmap helper ignores a write for a suspended device and returns as if it was actually written. It reduces the hardware access pretty much, e.g. when adjusting the mixer volume while in idle. This assumes that the driver will sync the cache later at resume properly, so use it carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-25 16:42:38 +03:00
int snd_hdac_regmap_write_raw(struct hdac_device *codec, unsigned int reg,
unsigned int val);
int snd_hdac_regmap_update_raw(struct hdac_device *codec, unsigned int reg,
unsigned int mask, unsigned int val);
/**
* snd_hdac_regmap_encode_verb - encode the verb to a pseudo register
* @nid: widget NID
* @verb: codec verb
*
* Returns an encoded pseudo register.
*/
#define snd_hdac_regmap_encode_verb(nid, verb) \
(((verb) << 8) | 0x80000 | ((unsigned int)(nid) << 20))
/**
* snd_hdac_regmap_encode_amp - encode the AMP verb to a pseudo register
* @nid: widget NID
* @ch: channel (left = 0, right = 1)
* @dir: direction (#HDA_INPUT, #HDA_OUTPUT)
* @idx: input index value
*
* Returns an encoded pseudo register.
*/
#define snd_hdac_regmap_encode_amp(nid, ch, dir, idx) \
(snd_hdac_regmap_encode_verb(nid, AC_VERB_GET_AMP_GAIN_MUTE) | \
((ch) ? AC_AMP_GET_RIGHT : AC_AMP_GET_LEFT) | \
((dir) == HDA_OUTPUT ? AC_AMP_GET_OUTPUT : AC_AMP_GET_INPUT) | \
(idx))
ALSA: hda - Add a fake stereo amp register support HD-audio spec is inconvenient regarding the handling of stereo volume controls. It can set and get only single channel at once (although there is a special option to set the same value to both channels). This patch provides a fake pseudo-register via the regmap access so that the stereo channels can be read and written by a single call. It'd be useful, for example, for implementing DAPM widgets. A stereo amp pseudo register consists of the encoding like the normal amp verbs but it has both SET_LEFT (bit 13) and SET_RIGHT (bit 12) bits set. The regmap reads and writes a 16bit value for this pseudo register where the upper 8bit is for the right chanel and the lower 8bit for the left channel. Note that the driver doesn't recognize conflicts when both stereo and mono channel registers are mixed. Mixing them would certainly confuse the operation. So, use carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-03-04 22:43:20 +03:00
/**
* snd_hdac_regmap_encode_amp_stereo - encode a pseudo register for stereo AMPs
* @nid: widget NID
* @dir: direction (#HDA_INPUT, #HDA_OUTPUT)
* @idx: input index value
*
* Returns an encoded pseudo register.
*/
#define snd_hdac_regmap_encode_amp_stereo(nid, dir, idx) \
(snd_hdac_regmap_encode_verb(nid, AC_VERB_GET_AMP_GAIN_MUTE) | \
AC_AMP_SET_LEFT | AC_AMP_SET_RIGHT | /* both bits set! */ \
((dir) == HDA_OUTPUT ? AC_AMP_GET_OUTPUT : AC_AMP_GET_INPUT) | \
(idx))
ALSA: hda - Add regmap support This patch adds an infrastructure to support regmap-based verb accesses. Because o the asymmetric nature of HD-audio verbs, especially the amp verbs, we need to translate the verbs as a sort of pseudo registers to be mapped uniquely in regmap. In this patch, a pseudo register is built from the NID, the AC_VERB_GET_* and 8bit parameters, i.e. almost in the form to be sent to HD-audio bus but without codec address field. OTOH, for writing, the same pseudo register is translated to AC_VERB_SET_* automatically. The AC_VERB_SET_AMP_* verb is re-encoded from the corresponding AC_VERB_GET_AMP_* verb and parameter at writing. Some verbs has a single command for read but multiple for writes. A write for such a verb is split automatically to multiple verbs. The patch provides also a few handy helper functions. They are designed to be accessible even without regmap. When no regmap is set up (e.g. before the codec device instantiation), the direct hardware access is used. Also, it tries to avoid the unnecessary power-up. The power up/down sequence is performed only on demand. The codec driver needs to call snd_hdac_regmap_exit() and snd_hdac_regmap_exit() at probe and remove if it wants the regmap access. There is one flag added to hdac_device. When the flag lazy_cache is set, regmap helper ignores a write for a suspended device and returns as if it was actually written. It reduces the hardware access pretty much, e.g. when adjusting the mixer volume while in idle. This assumes that the driver will sync the cache later at resume properly, so use it carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-25 16:42:38 +03:00
/**
* snd_hdac_regmap_write - Write a verb with caching
* @nid: codec NID
* @reg: verb to write
* @val: value to write
*
ALSA: hda - Fix typos in snd_hdac_regmap_*() documents Fixes the wrong reference names to regmap amp functions. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-09-28 13:19:08 +03:00
* For writing an amp value, use snd_hdac_regmap_update_amp().
ALSA: hda - Add regmap support This patch adds an infrastructure to support regmap-based verb accesses. Because o the asymmetric nature of HD-audio verbs, especially the amp verbs, we need to translate the verbs as a sort of pseudo registers to be mapped uniquely in regmap. In this patch, a pseudo register is built from the NID, the AC_VERB_GET_* and 8bit parameters, i.e. almost in the form to be sent to HD-audio bus but without codec address field. OTOH, for writing, the same pseudo register is translated to AC_VERB_SET_* automatically. The AC_VERB_SET_AMP_* verb is re-encoded from the corresponding AC_VERB_GET_AMP_* verb and parameter at writing. Some verbs has a single command for read but multiple for writes. A write for such a verb is split automatically to multiple verbs. The patch provides also a few handy helper functions. They are designed to be accessible even without regmap. When no regmap is set up (e.g. before the codec device instantiation), the direct hardware access is used. Also, it tries to avoid the unnecessary power-up. The power up/down sequence is performed only on demand. The codec driver needs to call snd_hdac_regmap_exit() and snd_hdac_regmap_exit() at probe and remove if it wants the regmap access. There is one flag added to hdac_device. When the flag lazy_cache is set, regmap helper ignores a write for a suspended device and returns as if it was actually written. It reduces the hardware access pretty much, e.g. when adjusting the mixer volume while in idle. This assumes that the driver will sync the cache later at resume properly, so use it carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-25 16:42:38 +03:00
*/
static inline int
snd_hdac_regmap_write(struct hdac_device *codec, hda_nid_t nid,
unsigned int verb, unsigned int val)
{
unsigned int cmd = snd_hdac_regmap_encode_verb(nid, verb);
return snd_hdac_regmap_write_raw(codec, cmd, val);
}
/**
* snd_hda_regmap_update - Update a verb value with caching
* @nid: codec NID
* @verb: verb to update
* @mask: bit mask to update
* @val: value to update
*
ALSA: hda - Fix typos in snd_hdac_regmap_*() documents Fixes the wrong reference names to regmap amp functions. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-09-28 13:19:08 +03:00
* For updating an amp value, use snd_hdac_regmap_update_amp().
ALSA: hda - Add regmap support This patch adds an infrastructure to support regmap-based verb accesses. Because o the asymmetric nature of HD-audio verbs, especially the amp verbs, we need to translate the verbs as a sort of pseudo registers to be mapped uniquely in regmap. In this patch, a pseudo register is built from the NID, the AC_VERB_GET_* and 8bit parameters, i.e. almost in the form to be sent to HD-audio bus but without codec address field. OTOH, for writing, the same pseudo register is translated to AC_VERB_SET_* automatically. The AC_VERB_SET_AMP_* verb is re-encoded from the corresponding AC_VERB_GET_AMP_* verb and parameter at writing. Some verbs has a single command for read but multiple for writes. A write for such a verb is split automatically to multiple verbs. The patch provides also a few handy helper functions. They are designed to be accessible even without regmap. When no regmap is set up (e.g. before the codec device instantiation), the direct hardware access is used. Also, it tries to avoid the unnecessary power-up. The power up/down sequence is performed only on demand. The codec driver needs to call snd_hdac_regmap_exit() and snd_hdac_regmap_exit() at probe and remove if it wants the regmap access. There is one flag added to hdac_device. When the flag lazy_cache is set, regmap helper ignores a write for a suspended device and returns as if it was actually written. It reduces the hardware access pretty much, e.g. when adjusting the mixer volume while in idle. This assumes that the driver will sync the cache later at resume properly, so use it carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-25 16:42:38 +03:00
*/
static inline int
snd_hdac_regmap_update(struct hdac_device *codec, hda_nid_t nid,
unsigned int verb, unsigned int mask,
unsigned int val)
{
unsigned int cmd = snd_hdac_regmap_encode_verb(nid, verb);
return snd_hdac_regmap_update_raw(codec, cmd, mask, val);
}
/**
* snd_hda_regmap_read - Read a verb with caching
* @nid: codec NID
* @verb: verb to read
* @val: pointer to store the value
*
* For reading an amp value, use snd_hda_regmap_get_amp().
*/
static inline int
snd_hdac_regmap_read(struct hdac_device *codec, hda_nid_t nid,
unsigned int verb, unsigned int *val)
{
unsigned int cmd = snd_hdac_regmap_encode_verb(nid, verb);
return snd_hdac_regmap_read_raw(codec, cmd, val);
}
/**
* snd_hdac_regmap_get_amp - Read AMP value
* @codec: HD-audio codec
* @nid: NID to read the AMP value
* @ch: channel (left=0 or right=1)
* @direction: #HDA_INPUT or #HDA_OUTPUT
* @index: the index value (only for input direction)
* @val: the pointer to store the value
*
* Read AMP value. The volume is between 0 to 0x7f, 0x80 = mute bit.
* Returns the value or a negative error.
*/
static inline int
snd_hdac_regmap_get_amp(struct hdac_device *codec, hda_nid_t nid,
int ch, int dir, int idx)
{
unsigned int cmd = snd_hdac_regmap_encode_amp(nid, ch, dir, idx);
int err, val;
err = snd_hdac_regmap_read_raw(codec, cmd, &val);
return err < 0 ? err : val;
}
/**
* snd_hdac_regmap_update_amp - update the AMP value
* @codec: HD-audio codec
* @nid: NID to read the AMP value
* @ch: channel (left=0 or right=1)
* @direction: #HDA_INPUT or #HDA_OUTPUT
* @idx: the index value (only for input direction)
* @mask: bit mask to set
* @val: the bits value to set
*
* Update the AMP value with a bit mask.
* Returns 0 if the value is unchanged, 1 if changed, or a negative error.
*/
static inline int
snd_hdac_regmap_update_amp(struct hdac_device *codec, hda_nid_t nid,
int ch, int dir, int idx, int mask, int val)
{
unsigned int cmd = snd_hdac_regmap_encode_amp(nid, ch, dir, idx);
return snd_hdac_regmap_update_raw(codec, cmd, mask, val);
}
ALSA: hda - Add a fake stereo amp register support HD-audio spec is inconvenient regarding the handling of stereo volume controls. It can set and get only single channel at once (although there is a special option to set the same value to both channels). This patch provides a fake pseudo-register via the regmap access so that the stereo channels can be read and written by a single call. It'd be useful, for example, for implementing DAPM widgets. A stereo amp pseudo register consists of the encoding like the normal amp verbs but it has both SET_LEFT (bit 13) and SET_RIGHT (bit 12) bits set. The regmap reads and writes a 16bit value for this pseudo register where the upper 8bit is for the right chanel and the lower 8bit for the left channel. Note that the driver doesn't recognize conflicts when both stereo and mono channel registers are mixed. Mixing them would certainly confuse the operation. So, use carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-03-04 22:43:20 +03:00
/**
* snd_hdac_regmap_get_amp_stereo - Read stereo AMP values
* @codec: HD-audio codec
* @nid: NID to read the AMP value
* @ch: channel (left=0 or right=1)
* @direction: #HDA_INPUT or #HDA_OUTPUT
* @index: the index value (only for input direction)
* @val: the pointer to store the value
*
* Read stereo AMP values. The lower byte is left, the upper byte is right.
* Returns the value or a negative error.
*/
static inline int
snd_hdac_regmap_get_amp_stereo(struct hdac_device *codec, hda_nid_t nid,
int dir, int idx)
{
unsigned int cmd = snd_hdac_regmap_encode_amp_stereo(nid, dir, idx);
int err, val;
err = snd_hdac_regmap_read_raw(codec, cmd, &val);
return err < 0 ? err : val;
}
/**
* snd_hdac_regmap_update_amp_stereo - update the stereo AMP value
* @codec: HD-audio codec
* @nid: NID to read the AMP value
* @direction: #HDA_INPUT or #HDA_OUTPUT
* @idx: the index value (only for input direction)
* @mask: bit mask to set
* @val: the bits value to set
*
* Update the stereo AMP value with a bit mask.
* The lower byte is left, the upper byte is right.
* Returns 0 if the value is unchanged, 1 if changed, or a negative error.
*/
static inline int
snd_hdac_regmap_update_amp_stereo(struct hdac_device *codec, hda_nid_t nid,
int dir, int idx, int mask, int val)
{
unsigned int cmd = snd_hdac_regmap_encode_amp_stereo(nid, dir, idx);
return snd_hdac_regmap_update_raw(codec, cmd, mask, val);
}
ALSA: hda - Sync node attributes at resume from widget power saving So far we assumed that the node attributes like amp values remain during the power state transition of the node itself. While this is true for IDT/STAC codecs I've tested, but some other codecs don't seem behaving in that way. This patch implements a partial sync mechanism specific to the given widget node. Now we've merged the regmap support, and it can be easily written with regcache_sync_region(). Tested-by: Hui Wang <hui.wang@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-04-04 13:17:28 +03:00
/**
* snd_hdac_regmap_sync_node - sync the widget node attributes
* @codec: HD-audio codec
* @nid: NID to sync
*/
static inline void
snd_hdac_regmap_sync_node(struct hdac_device *codec, hda_nid_t nid)
{
regcache_mark_dirty(codec->regmap);
regcache_sync_region(codec->regmap, nid << 20, ((nid + 1) << 20) - 1);
}
ALSA: hda - Add regmap support This patch adds an infrastructure to support regmap-based verb accesses. Because o the asymmetric nature of HD-audio verbs, especially the amp verbs, we need to translate the verbs as a sort of pseudo registers to be mapped uniquely in regmap. In this patch, a pseudo register is built from the NID, the AC_VERB_GET_* and 8bit parameters, i.e. almost in the form to be sent to HD-audio bus but without codec address field. OTOH, for writing, the same pseudo register is translated to AC_VERB_SET_* automatically. The AC_VERB_SET_AMP_* verb is re-encoded from the corresponding AC_VERB_GET_AMP_* verb and parameter at writing. Some verbs has a single command for read but multiple for writes. A write for such a verb is split automatically to multiple verbs. The patch provides also a few handy helper functions. They are designed to be accessible even without regmap. When no regmap is set up (e.g. before the codec device instantiation), the direct hardware access is used. Also, it tries to avoid the unnecessary power-up. The power up/down sequence is performed only on demand. The codec driver needs to call snd_hdac_regmap_exit() and snd_hdac_regmap_exit() at probe and remove if it wants the regmap access. There is one flag added to hdac_device. When the flag lazy_cache is set, regmap helper ignores a write for a suspended device and returns as if it was actually written. It reduces the hardware access pretty much, e.g. when adjusting the mixer volume while in idle. This assumes that the driver will sync the cache later at resume properly, so use it carefully. Signed-off-by: Takashi Iwai <tiwai@suse.de>
2015-02-25 16:42:38 +03:00
#endif /* __SOUND_HDA_REGMAP_H */