regmap: sdw: check for invalid multi-register writes config

SoundWire code as it is only supports Bulk register writes and
it does not support multi-register writes.

Any drivers that set can_multi_write and use regmap_multi_reg_write() will
easily endup with programming the hardware incorrectly without any errors.

So, add this check in bus code to be able to validate the drivers config.

Fixes: 522272047dc6 ("regmap: sdw: Remove 8-bit value size restriction")
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20230523154747.5429-1-srinivas.kandagatla@linaro.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regmap: sdw: Remove 8-bit value size restriction

Some SoundWire devices have larger width device specific register
maps, in addition to the standard SoundWire 8-bit map. Update the
helpers to allow accessing arbitrarily sized register values and remove
the explicit 8-bit restriction from regmap_sdw_config_check.

Signed-off-by: Lucas Tanure <tanureal@opensource.cirrus.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230112171840.2098463-3-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regmap: sdw: Update misleading comment

In the regmap config reg_bits represents the number of address bits not
the number of value bits. Correct the misleading comment which looks a
lot like it suggests the register value itself is 32-bits wide.

Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20230112171840.2098463-2-ckeepax@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regmap: Constify static regmap_bus structs

The only usage of these is to pass their address to __regmap_init() or
__devm_regmap_init(), both which takes pointers to const struct
regmap_bus. Make them const to allow the compiler to put them in
read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20220330214110.36337-1-rikard.falkeborn@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regmap: sdw: use _no_pm functions in regmap_read/write

sdw_update_slave_status will be invoked when a codec is attached,
and the codec driver will initialize the codec with regmap functions
while the codec device is pm_runtime suspended.

regmap routines currently rely on regular SoundWire IO functions,
which will call pm_runtime_get_sync()/put_autosuspend.

This causes a deadlock where the resume routine waits for an
initialization complete signal that while the initialization complete
can only be reached when the resume completes.

The only solution if we allow regmap functions to be used in resume
operations as well as during codec initialization is to use _no_pm
routines. The duty of making sure the bus is operational needs to be
handled above the regmap level.

Fixes: 7c22ce6e21840 ('regmap: Add SoundWire bus support')
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210122070634.12825-6-yung-chuan.liao@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

regmap: sdw: add required header files

Explicitly add header files used by regmap SoundWire support.

Suggested-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@linux.intel.com>
Reviewed-by: Guennadi Liakhovetski <guennadi.liakhovetski@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20201125130128.15952-1-yung-chuan.liao@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

regmap: soundwire: remove unused header mod_devicetable.h

mod_devicetable.h does not seem to be required for this file, so
remove it.

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Link: https://lore.kernel.org/r/20200829103939.4007097-1-vkoul@kernel.org
Signed-off-by: Mark Brown <broonie@kernel.org>

regmap: Add SoundWire bus support

SoundWire bus provides sdw_read() and sdw_write() APIs for Slave
devices to program the registers. Provide support in regmap for
SoundWire bus.

Signed-off-by: Hardik T Shah <hardik.t.shah@intel.com>
Signed-off-by: Sanyog Kale <sanyog.r.kale@intel.com>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Acked-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>