[PATCH 0/4] ASoC: cs35l56: Update hibernate/wake sequences and enable hibernation

[PATCH 0/4] ASoC: cs35l56: Update hibernate/wake sequences and enable hibernation

[Richard Fitzgerald]

Update the hibernate and wake command sequences to meet the latest
datasheet specification and enable hibernation for I2C and SPI control
interfaces.

Richard Fitzgerald (1):
  ASoC: cs35l56: Enable low-power hibernation mode on SPI

Simon Trimmer (3):
  ASoC: cs35l56: Change hibernate sequence to use allow auto hibernate
  ASoC: cs35l56: Wake transactions need to be issued twice
  ASoC: cs35l56: Enable low-power hibernation mode on i2c

 include/sound/cs35l56.h           |  1 +
 sound/soc/codecs/cs35l56-i2c.c    |  1 +
 sound/soc/codecs/cs35l56-shared.c | 66 +++++++++++++++++++------------
 sound/soc/codecs/cs35l56-spi.c    |  1 +
 4 files changed, 43 insertions(+), 26 deletions(-)

-- 
2.30.2

[PATCH 1/4] ASoC: cs35l56: Change hibernate sequence to use allow auto hibernate

[Richard Fitzgerald]

From: Simon Trimmer <simont@opensource.cirrus.com>

If the hardware uses SPI_MOSI, I2C_SCL or I2C_SDA as the wake source
the bus activity of sending HIBERNATE_NOW will wake up the amps that
were already put into hibernate.

ALLOW_AUTO_HIBERNATE tells the firmware to hibernate itself after a
timeout of a few seconds, giving the driver instances time to send this
before any amps have gone into hibernate.

Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs35l56-shared.c | 15 +++++----------
 1 file changed, 5 insertions(+), 10 deletions(-)

diff --git a/sound/soc/codecs/cs35l56-shared.c b/sound/soc/codecs/cs35l56-shared.c
index 01b6fa97b36b..68dc93b82789 100644
--- a/sound/soc/codecs/cs35l56-shared.c
+++ b/sound/soc/codecs/cs35l56-shared.c
@@ -439,7 +439,7 @@ EXPORT_SYMBOL_NS_GPL(cs35l56_is_fw_reload_needed, SND_SOC_CS35L56_SHARED);
 
 static const struct reg_sequence cs35l56_hibernate_seq[] = {
 	/* This must be the last register access */
-	REG_SEQ0(CS35L56_DSP_VIRTUAL1_MBOX_1, CS35L56_MBOX_CMD_HIBERNATE_NOW),
+	REG_SEQ0(CS35L56_DSP_VIRTUAL1_MBOX_1, CS35L56_MBOX_CMD_ALLOW_AUTO_HIBERNATE),
 };
 
 static const struct reg_sequence cs35l56_hibernate_wake_seq[] = {
@@ -473,12 +473,6 @@ int cs35l56_runtime_suspend_common(struct cs35l56_base *cs35l56_base)
 		return 0;
 	}
 
-	/*
-	 * Enable auto-hibernate. If it is woken by some other wake source
-	 * it will automatically return to hibernate.
-	 */
-	cs35l56_mbox_send(cs35l56_base, CS35L56_MBOX_CMD_ALLOW_AUTO_HIBERNATE);
-
 	/*
 	 * Must enter cache-only first so there can't be any more register
 	 * accesses other than the controlled hibernate sequence below.
@@ -545,11 +539,12 @@ int cs35l56_runtime_resume_common(struct cs35l56_base *cs35l56_base, bool is_sou
 	return 0;
 
 err:
-	regmap_write(cs35l56_base->regmap, CS35L56_DSP_VIRTUAL1_MBOX_1,
-		     CS35L56_MBOX_CMD_HIBERNATE_NOW);
-
 	regcache_cache_only(cs35l56_base->regmap, true);
 
+	regmap_multi_reg_write_bypassed(cs35l56_base->regmap,
+					cs35l56_hibernate_seq,
+					ARRAY_SIZE(cs35l56_hibernate_seq));
+
 	return ret;
 }
 EXPORT_SYMBOL_NS_GPL(cs35l56_runtime_resume_common, SND_SOC_CS35L56_SHARED);
-- 
2.30.2

[PATCH 2/4] ASoC: cs35l56: Wake transactions need to be issued twice

[Richard Fitzgerald]

From: Simon Trimmer <simont@opensource.cirrus.com>

As the dummy wake is a toggling signal (either I2C or SPI activity) it
is not guaranteed to meet the minimum asserted hold time for a wake
signal. In this case the wake must guarantee rising edges separated by
at least the minimum hold time.

Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 include/sound/cs35l56.h           |  1 +
 sound/soc/codecs/cs35l56-shared.c | 51 +++++++++++++++++++++----------
 2 files changed, 36 insertions(+), 16 deletions(-)

diff --git a/include/sound/cs35l56.h b/include/sound/cs35l56.h
index 762b96b29211..8c18e8b6d27d 100644
--- a/include/sound/cs35l56.h
+++ b/include/sound/cs35l56.h
@@ -243,6 +243,7 @@
 #define CS35L56_HALO_STATE_POLL_US			1000
 #define CS35L56_HALO_STATE_TIMEOUT_US			50000
 #define CS35L56_RESET_PULSE_MIN_US			1100
+#define CS35L56_WAKE_HOLD_TIME_US			1000
 
 #define CS35L56_SDW1_PLAYBACK_PORT			1
 #define CS35L56_SDW1_CAPTURE_PORT			3
diff --git a/sound/soc/codecs/cs35l56-shared.c b/sound/soc/codecs/cs35l56-shared.c
index 68dc93b82789..953ba066bab1 100644
--- a/sound/soc/codecs/cs35l56-shared.c
+++ b/sound/soc/codecs/cs35l56-shared.c
@@ -446,6 +446,32 @@ static const struct reg_sequence cs35l56_hibernate_wake_seq[] = {
 	REG_SEQ0(CS35L56_DSP_VIRTUAL1_MBOX_1, CS35L56_MBOX_CMD_WAKEUP),
 };
 
+static void cs35l56_issue_wake_event(struct cs35l56_base *cs35l56_base)
+{
+	/*
+	 * Dummy transactions to trigger I2C/SPI auto-wake. Issue two
+	 * transactions to meet the minimum required time from the rising edge
+	 * to the last falling edge of wake.
+	 *
+	 * It uses bypassed write because we must wake the chip before
+	 * disabling regmap cache-only.
+	 *
+	 * This can NAK on I2C which will terminate the write sequence so the
+	 * single-write sequence is issued twice.
+	 */
+	regmap_multi_reg_write_bypassed(cs35l56_base->regmap,
+					cs35l56_hibernate_wake_seq,
+					ARRAY_SIZE(cs35l56_hibernate_wake_seq));
+
+	usleep_range(CS35L56_WAKE_HOLD_TIME_US, 2 * CS35L56_WAKE_HOLD_TIME_US);
+
+	regmap_multi_reg_write_bypassed(cs35l56_base->regmap,
+					cs35l56_hibernate_wake_seq,
+					ARRAY_SIZE(cs35l56_hibernate_wake_seq));
+
+	cs35l56_wait_control_port_ready();
+}
+
 int cs35l56_runtime_suspend_common(struct cs35l56_base *cs35l56_base)
 {
 	unsigned int val;
@@ -500,17 +526,9 @@ int cs35l56_runtime_resume_common(struct cs35l56_base *cs35l56_base, bool is_sou
 	if (!cs35l56_base->can_hibernate)
 		goto out_sync;
 
-	if (!is_soundwire) {
-		/*
-		 * Dummy transaction to trigger I2C/SPI auto-wake. This will NAK on I2C.
-		 * Must be done before releasing cache-only.
-		 */
-		regmap_multi_reg_write_bypassed(cs35l56_base->regmap,
-						cs35l56_hibernate_wake_seq,
-						ARRAY_SIZE(cs35l56_hibernate_wake_seq));
-
-		cs35l56_wait_control_port_ready();
-	}
+	/* Must be done before releasing cache-only */
+	if (!is_soundwire)
+		cs35l56_issue_wake_event(cs35l56_base);
 
 out_sync:
 	regcache_cache_only(cs35l56_base->regmap, false);
@@ -578,13 +596,14 @@ int cs35l56_hw_init(struct cs35l56_base *cs35l56_base)
 	unsigned int devid, revid, otpid, secured;
 
 	/*
-	 * If the system is not using a reset_gpio then issue a
-	 * dummy read to force a wakeup.
+	 * When the system is not using a reset_gpio ensure the device is
+	 * awake, otherwise the device has just been released from reset and
+	 * the driver must wait for the control port to become usable.
 	 */
 	if (!cs35l56_base->reset_gpio)
-		regmap_read(cs35l56_base->regmap, CS35L56_DSP_VIRTUAL1_MBOX_1, &devid);
-
-	cs35l56_wait_control_port_ready();
+		cs35l56_issue_wake_event(cs35l56_base);
+	else
+		cs35l56_wait_control_port_ready();
 
 	/*
 	 * The HALO_STATE register is in different locations on Ax and B0
-- 
2.30.2

[PATCH 3/4] ASoC: cs35l56: Enable low-power hibernation mode on i2c

[Richard Fitzgerald]

From: Simon Trimmer <simont@opensource.cirrus.com>

This can now be re-enabled as the sequence to reliably wake the device
has been implemented in the shared code.

Signed-off-by: Simon Trimmer <simont@opensource.cirrus.com>
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs35l56-i2c.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sound/soc/codecs/cs35l56-i2c.c b/sound/soc/codecs/cs35l56-i2c.c
index 9e5670b09af6..7063c400e896 100644
--- a/sound/soc/codecs/cs35l56-i2c.c
+++ b/sound/soc/codecs/cs35l56-i2c.c
@@ -27,6 +27,7 @@ static int cs35l56_i2c_probe(struct i2c_client *client)
 		return -ENOMEM;
 
 	cs35l56->base.dev = dev;
+	cs35l56->base.can_hibernate = true;
 
 	i2c_set_clientdata(client, cs35l56);
 	cs35l56->base.regmap = devm_regmap_init_i2c(client, regmap_config);
-- 
2.30.2

[PATCH 4/4] ASoC: cs35l56: Enable low-power hibernation mode on SPI

[Richard Fitzgerald]

Hibernation can be enabled on SPI-connected devices now that
the hibernate and wake sequences have been updated to work
with wake-on-MOSI.

Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
---
 sound/soc/codecs/cs35l56-spi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sound/soc/codecs/cs35l56-spi.c b/sound/soc/codecs/cs35l56-spi.c
index 768ffe8213dc..b07b798b0b45 100644
--- a/sound/soc/codecs/cs35l56-spi.c
+++ b/sound/soc/codecs/cs35l56-spi.c
@@ -32,6 +32,7 @@ static int cs35l56_spi_probe(struct spi_device *spi)
 	}
 
 	cs35l56->base.dev = &spi->dev;
+	cs35l56->base.can_hibernate = true;
 
 	ret = cs35l56_common_probe(cs35l56);
 	if (ret != 0)
-- 
2.30.2

Re: [PATCH 0/4] ASoC: cs35l56: Update hibernate/wake sequences and enable hibernation

[Mark Brown]

On Fri, 06 Oct 2023 12:10:35 +0100, Richard Fitzgerald wrote:
> Update the hibernate and wake command sequences to meet the latest
> datasheet specification and enable hibernation for I2C and SPI control
> interfaces.
> 
> Richard Fitzgerald (1):
>   ASoC: cs35l56: Enable low-power hibernation mode on SPI
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/4] ASoC: cs35l56: Change hibernate sequence to use allow auto hibernate
      commit: a47cf4dac7dcc43ef25d009ca0ad28fc86ba0eef
[2/4] ASoC: cs35l56: Wake transactions need to be issued twice
      commit: 3df761bdbc8bc1bb679b5a4d4e068728d930a552
[3/4] ASoC: cs35l56: Enable low-power hibernation mode on i2c
      commit: 79b101947a829a1c4c3eca4b6365093d2b534cf4
[4/4] ASoC: cs35l56: Enable low-power hibernation mode on SPI
      commit: 634ed138d80b1cc8a903edb226458ea203c44abd

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark