linux/include/sound/hda_regmap.h

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License cleanup: add SPDX GPL-2.0 license identifier to files with no license Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 14:07:57 +00:00
/* SPDX-License-Identifier: GPL-2.0 */
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 13:42:38 +00:00
/*
* 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>
#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 13:42:38 +00:00
int snd_hdac_regmap_init(struct hdac_device *codec);
void snd_hdac_regmap_exit(struct hdac_device *codec);
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 13:42:38 +00:00
int snd_hdac_regmap_read_raw(struct hdac_device *codec, unsigned int reg,
unsigned int *val);
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 13:42:38 +00:00
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))
/**
* 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 13:42:38 +00:00
/**
* snd_hdac_regmap_write - Write a verb with caching
* @nid: codec NID
* @reg: verb to write
* @val: value to write
*
* 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 13:42:38 +00:00
*/
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
*
* 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 13:42:38 +00:00
*/
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);
}
/**
* 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);
}
/**
* 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 13:42:38 +00:00
#endif /* __SOUND_HDA_REGMAP_H */