* [PATCH v4 2/3] ASoC: cs35l56: Use reg_base to offset addresses on SoundWire
2026-05-21 11:54 [PATCH v4 0/3] ASoC: cs35l56: Replace open-coded SoundWire regmap with generic regmap-sdw Richard Fitzgerald
2026-05-21 11:54 ` [PATCH v4 1/3] ASoC: cs35l56-shared-test: Subtract reg_base offset in dummy regmap Richard Fitzgerald
@ 2026-05-21 11:54 ` Richard Fitzgerald
2026-05-21 11:54 ` [PATCH v4 3/3] ASoC: cs35l56: Use standard SoundWire regmap implementation Richard Fitzgerald
2026-05-21 23:17 ` [PATCH v4 0/3] ASoC: cs35l56: Replace open-coded SoundWire regmap with generic regmap-sdw Mark Brown
3 siblings, 0 replies; 5+ messages in thread
From: Richard Fitzgerald @ 2026-05-21 11:54 UTC (permalink / raw)
To: broonie; +Cc: linux-sound, linux-kernel, patches
Set the reg_base member of regmap_config for SoundWire so that
the regmap core will apply the 0x8000 offset to addresses, instead
of doing it within our low-level regmap read/write callbacks.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
No changes in V4
No changes in V3
No changes in V2
sound/soc/codecs/cs35l56-sdw.c | 7 +------
sound/soc/codecs/cs35l56-shared.c | 2 ++
2 files changed, 3 insertions(+), 6 deletions(-)
diff --git a/sound/soc/codecs/cs35l56-sdw.c b/sound/soc/codecs/cs35l56-sdw.c
index d5b9e5f71de2..d9dcca1e952f 100644
--- a/sound/soc/codecs/cs35l56-sdw.c
+++ b/sound/soc/codecs/cs35l56-sdw.c
@@ -59,8 +59,6 @@ static int cs35l56_sdw_slow_read(struct sdw_slave *peripheral, unsigned int reg,
{
int ret, i;
- reg += CS35L56_SDW_ADDR_OFFSET;
-
for (i = 0; i < val_size; i += sizeof(u32)) {
/* Poll for bus bridge idle */
ret = cs35l56_sdw_poll_mem_status(peripheral,
@@ -123,11 +121,9 @@ static int cs35l56_sdw_read(void *context, const void *reg_buf,
reg = le32_to_cpu(*(const __le32 *)reg_buf);
- if (cs35l56_is_otp_register(reg))
+ if (cs35l56_is_otp_register(reg - CS35L56_SDW_ADDR_OFFSET))
return cs35l56_sdw_slow_read(peripheral, reg, buf8, val_size);
- reg += CS35L56_SDW_ADDR_OFFSET;
-
if (val_size == 4)
return cs35l56_sdw_read_one(peripheral, reg, val_buf);
@@ -186,7 +182,6 @@ static int cs35l56_sdw_gather_write(void *context,
int ret;
reg = le32_to_cpu(*(const __le32 *)reg_buf);
- reg += CS35L56_SDW_ADDR_OFFSET;
if (val_size == 4)
return cs35l56_sdw_write_one(peripheral, reg, src_be);
diff --git a/sound/soc/codecs/cs35l56-shared.c b/sound/soc/codecs/cs35l56-shared.c
index 795e2764d67e..8e3538e28fad 100644
--- a/sound/soc/codecs/cs35l56-shared.c
+++ b/sound/soc/codecs/cs35l56-shared.c
@@ -1880,6 +1880,7 @@ EXPORT_SYMBOL_NS_GPL(cs35l56_regmap_spi, "SND_SOC_CS35L56_SHARED");
const struct regmap_config cs35l56_regmap_sdw = {
.reg_bits = 32,
+ .reg_base = 0x8000,
.val_bits = 32,
.reg_stride = 4,
.reg_format_endian = REGMAP_ENDIAN_LITTLE,
@@ -1915,6 +1916,7 @@ const struct regmap_config cs35l63_regmap_sdw = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
+ .reg_base = 0x8000,
.reg_format_endian = REGMAP_ENDIAN_LITTLE,
.val_format_endian = REGMAP_ENDIAN_BIG,
.max_register = CS35L56_DSP1_PMEM_5114,
--
2.47.3
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v4 3/3] ASoC: cs35l56: Use standard SoundWire regmap implementation
2026-05-21 11:54 [PATCH v4 0/3] ASoC: cs35l56: Replace open-coded SoundWire regmap with generic regmap-sdw Richard Fitzgerald
2026-05-21 11:54 ` [PATCH v4 1/3] ASoC: cs35l56-shared-test: Subtract reg_base offset in dummy regmap Richard Fitzgerald
2026-05-21 11:54 ` [PATCH v4 2/3] ASoC: cs35l56: Use reg_base to offset addresses on SoundWire Richard Fitzgerald
@ 2026-05-21 11:54 ` Richard Fitzgerald
2026-05-21 23:17 ` [PATCH v4 0/3] ASoC: cs35l56: Replace open-coded SoundWire regmap with generic regmap-sdw Mark Brown
3 siblings, 0 replies; 5+ messages in thread
From: Richard Fitzgerald @ 2026-05-21 11:54 UTC (permalink / raw)
To: broonie; +Cc: linux-sound, linux-kernel, patches
Use the regmap_sdw implementation for SoundWire instead of
re-implementing the low-level bus transactions in cs35l56-sdw.c
The cs35l56 registers are big-endian on I2C and SPI but little-endian
over SoundWire. The firmware files are all big-endian and contain opaque
blobs in big-endian order. So these must be endian-swapped to transfer
over SoundWire. A custom regmap bus implementation is used to do this
endian-swapping.
The original implementation of this custom regmap bus was a complete bus
backend, performing the endian swapping and low-level SoundWire bus
read/write.
This commit changes the custom regmap bus to only perform the endian-swap.
It uses an underlying simple uncached regmap_sdw bus to deal with
transferring the 32-bit registers over the SoundWire bus. Although this
adds a small amount of overhead, from passing through the regmap APIs
twice, it avoids having a local duplicate implementation of what regmap_sdw
already does.
The slow-read handling for OTP registers must access 8-bit SoundWire
registers so it still uses low-level SoundWire bus reads.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
No changes in V4
No changes in V3
Changed in V2:
- Select REGMAP_SOUNDWIRE
sound/soc/codecs/Kconfig | 2 +-
sound/soc/codecs/cs35l56-sdw.c | 132 ++++++++++++---------------------
sound/soc/codecs/cs35l56.h | 1 +
3 files changed, 51 insertions(+), 84 deletions(-)
diff --git a/sound/soc/codecs/Kconfig b/sound/soc/codecs/Kconfig
index 5fdd0334c355..a7c61f7c7f4c 100644
--- a/sound/soc/codecs/Kconfig
+++ b/sound/soc/codecs/Kconfig
@@ -887,7 +887,7 @@ config SND_SOC_CS35L56_SPI
config SND_SOC_CS35L56_SDW
tristate "Cirrus Logic CS35L56 CODEC (SDW)"
depends on SOUNDWIRE
- select REGMAP
+ select REGMAP_SOUNDWIRE
select SND_SOC_CS35L56
select SND_SOC_CS35L56_SHARED
help
diff --git a/sound/soc/codecs/cs35l56-sdw.c b/sound/soc/codecs/cs35l56-sdw.c
index d9dcca1e952f..d2b82a846ae8 100644
--- a/sound/soc/codecs/cs35l56-sdw.c
+++ b/sound/soc/codecs/cs35l56-sdw.c
@@ -17,6 +17,7 @@
#include <linux/string_choices.h>
#include <linux/swab.h>
#include <linux/types.h>
+#include <linux/unaligned.h>
#include <linux/workqueue.h>
#include "cs35l56.h"
@@ -95,55 +96,23 @@ static int cs35l56_sdw_slow_read(struct sdw_slave *peripheral, unsigned int reg,
return 0;
}
-static int cs35l56_sdw_read_one(struct sdw_slave *peripheral, unsigned int reg, void *buf)
-{
- int ret;
-
- ret = sdw_nread_no_pm(peripheral, reg, 4, (u8 *)buf);
- if (ret != 0) {
- dev_err(&peripheral->dev, "Read failed @%#x:%d\n", reg, ret);
- return ret;
- }
-
- swab32s((u32 *)buf);
-
- return 0;
-}
-
static int cs35l56_sdw_read(void *context, const void *reg_buf,
const size_t reg_size, void *val_buf,
size_t val_size)
{
struct sdw_slave *peripheral = context;
- u8 *buf8 = val_buf;
- unsigned int reg, bytes;
+ struct cs35l56_private *cs35l56 = dev_get_drvdata(&peripheral->dev);
+ unsigned int reg_addr = get_unaligned_le32(reg_buf);
int ret;
- reg = le32_to_cpu(*(const __le32 *)reg_buf);
+ if (cs35l56_is_otp_register(reg_addr - CS35L56_SDW_ADDR_OFFSET))
+ return cs35l56_sdw_slow_read(peripheral, reg_addr, (u8 *)val_buf, val_size);
- if (cs35l56_is_otp_register(reg - CS35L56_SDW_ADDR_OFFSET))
- return cs35l56_sdw_slow_read(peripheral, reg, buf8, val_size);
+ ret = regmap_raw_read(cs35l56->sdw_bus_regmap, reg_addr, val_buf, val_size);
+ if (ret)
+ return ret;
- if (val_size == 4)
- return cs35l56_sdw_read_one(peripheral, reg, val_buf);
-
- while (val_size) {
- bytes = SDW_REG_NO_PAGE - (reg & SDW_REGADDR); /* to end of page */
- if (bytes > val_size)
- bytes = val_size;
-
- ret = sdw_nread_no_pm(peripheral, reg, bytes, buf8);
- if (ret != 0) {
- dev_err(&peripheral->dev, "Read failed @%#x..%#x:%d\n",
- reg, reg + bytes - 1, ret);
- return ret;
- }
-
- swab32_array((u32 *)buf8, bytes / 4);
- val_size -= bytes;
- reg += bytes;
- buf8 += bytes;
- }
+ swab32_array((u32 *)val_buf, val_size / sizeof(u32));
return 0;
}
@@ -157,57 +126,34 @@ static inline void cs35l56_swab_copy(void *dest, const void *src, size_t nbytes)
*dest32++ = swab32(*src32++);
}
-static int cs35l56_sdw_write_one(struct sdw_slave *peripheral, unsigned int reg, const void *buf)
-{
- u32 val_le = swab32(*(u32 *)buf);
- int ret;
-
- ret = sdw_nwrite_no_pm(peripheral, reg, 4, (u8 *)&val_le);
- if (ret != 0) {
- dev_err(&peripheral->dev, "Write failed @%#x:%d\n", reg, ret);
- return ret;
- }
-
- return 0;
-}
-
static int cs35l56_sdw_gather_write(void *context,
const void *reg_buf, size_t reg_size,
const void *val_buf, size_t val_size)
{
struct sdw_slave *peripheral = context;
- const u8 *src_be = val_buf;
- u32 val_le_buf[64]; /* Define u32 so it is 32-bit aligned */
- unsigned int reg, bytes;
+ struct cs35l56_private *cs35l56 = dev_get_drvdata(&peripheral->dev);
+ unsigned int reg_addr = get_unaligned_le32(reg_buf);
+ u32 swab_buf[64]; /* Define u32 so it is 32-bit aligned */
int ret;
- reg = le32_to_cpu(*(const __le32 *)reg_buf);
-
- if (val_size == 4)
- return cs35l56_sdw_write_one(peripheral, reg, src_be);
-
- while (val_size) {
- bytes = SDW_REG_NO_PAGE - (reg & SDW_REGADDR); /* to end of page */
- if (bytes > val_size)
- bytes = val_size;
- if (bytes > sizeof(val_le_buf))
- bytes = sizeof(val_le_buf);
-
- cs35l56_swab_copy(val_le_buf, src_be, bytes);
-
- ret = sdw_nwrite_no_pm(peripheral, reg, bytes, (u8 *)val_le_buf);
- if (ret != 0) {
- dev_err(&peripheral->dev, "Write failed @%#x..%#x:%d\n",
- reg, reg + bytes - 1, ret);
+ while (val_size > sizeof(swab_buf)) {
+ cs35l56_swab_copy(swab_buf, val_buf, sizeof(swab_buf));
+ ret = regmap_raw_write(cs35l56->sdw_bus_regmap, reg_addr,
+ swab_buf, sizeof(swab_buf));
+ if (ret)
return ret;
- }
- val_size -= bytes;
- reg += bytes;
- src_be += bytes;
+ val_size -= sizeof(swab_buf);
+ reg_addr += sizeof(swab_buf);
+ val_buf += sizeof(swab_buf);
}
- return 0;
+ if (val_size == 0)
+ return 0;
+
+ cs35l56_swab_copy(swab_buf, val_buf, val_size);
+
+ return regmap_raw_write(cs35l56->sdw_bus_regmap, reg_addr, swab_buf, val_size);
}
static int cs35l56_sdw_write(void *context, const void *val_buf, size_t val_size)
@@ -226,7 +172,7 @@ static int cs35l56_sdw_write(void *context, const void *val_buf, size_t val_size
* byte controls always have the same byte order, and firmware file blobs
* can be written verbatim.
*/
-static const struct regmap_bus cs35l56_regmap_bus_sdw = {
+static const struct regmap_bus cs35l56_regmap_swab_bus_sdw = {
.read = cs35l56_sdw_read,
.write = cs35l56_sdw_write,
.gather_write = cs35l56_sdw_gather_write,
@@ -234,6 +180,18 @@ static const struct regmap_bus cs35l56_regmap_bus_sdw = {
.val_format_endian_default = REGMAP_ENDIAN_BIG,
};
+/* Low-level SoundWire regmap to transfer the data over the bus */
+static const struct regmap_config cs35l56_sdw_bus_regmap = {
+ .name = "sdw-le32",
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .reg_format_endian = REGMAP_ENDIAN_LITTLE,
+ .val_format_endian = REGMAP_ENDIAN_LITTLE,
+ .max_register = CS35L56_DSP1_PMEM_5114 + 0x8000,
+ .cache_type = REGCACHE_NONE,
+};
+
static int cs35l56_sdw_get_unique_id(struct cs35l56_private *cs35l56)
{
int ret;
@@ -555,8 +513,16 @@ static int cs35l56_sdw_probe(struct sdw_slave *peripheral, const struct sdw_devi
cs35l56->base.type = ((unsigned int)id->driver_data) & 0xff;
- cs35l56->base.regmap = devm_regmap_init(dev, &cs35l56_regmap_bus_sdw,
- peripheral, regmap_config);
+ /* Low-level regmap to transfer read/writes over SoundWire bus */
+ cs35l56->sdw_bus_regmap = devm_regmap_init_sdw(peripheral, &cs35l56_sdw_bus_regmap);
+ if (IS_ERR(cs35l56->sdw_bus_regmap)) {
+ ret = PTR_ERR(cs35l56->sdw_bus_regmap);
+ return dev_err_probe(dev, ret, "Failed to allocate bus register map\n");
+ }
+
+ /* Wrapper regmap to simulate big-endian ordering */
+ cs35l56->base.regmap = devm_regmap_init(dev, &cs35l56_regmap_swab_bus_sdw,
+ peripheral, regmap_config);
if (IS_ERR(cs35l56->base.regmap)) {
ret = PTR_ERR(cs35l56->base.regmap);
return dev_err_probe(dev, ret, "Failed to allocate register map\n");
diff --git a/sound/soc/codecs/cs35l56.h b/sound/soc/codecs/cs35l56.h
index cd71b23b2a3a..d029fa3f8656 100644
--- a/sound/soc/codecs/cs35l56.h
+++ b/sound/soc/codecs/cs35l56.h
@@ -37,6 +37,7 @@ struct cs35l56_private {
struct snd_soc_component *component;
struct regulator_bulk_data supplies[CS35L56_NUM_BULK_SUPPLIES];
struct sdw_slave *sdw_peripheral;
+ struct regmap *sdw_bus_regmap;
const char *fallback_fw_suffix;
struct work_struct sdw_irq_work;
bool sdw_irq_no_unmask;
--
2.47.3
^ permalink raw reply related [flat|nested] 5+ messages in thread