diff mbox series

ASoC: sgtl5000: Fix VAG power-on handling

Message ID 20200414181140.145825-1-sebastian.reichel@collabora.com (mailing list archive)
State Accepted
Commit aa7812737f2877e192d57626cbe8825cc7cf6de9
Headers show
Series ASoC: sgtl5000: Fix VAG power-on handling | expand

Commit Message

Sebastian Reichel April 14, 2020, 6:11 p.m. UTC
As mentioned slightly out of patch context in the code, there
is no reset routine for the chip. On boards where the chip is
supplied by a fixed regulator, it might not even be resetted
during (e.g. watchdog) reboot and can be in any state.

If the device is probed with VAG enabled, the driver's probe
routine will generate a loud pop sound when ANA_POWER is
being programmed. Avoid this by properly disabling just the
VAG bit and waiting the required power down time.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
---
 sound/soc/codecs/sgtl5000.c | 34 ++++++++++++++++++++++++++++++++++
 sound/soc/codecs/sgtl5000.h |  1 +
 2 files changed, 35 insertions(+)

Comments

Fabio Estevam April 14, 2020, 7:01 p.m. UTC | #1
Hi Sebastian,

On Tue, Apr 14, 2020 at 3:11 PM Sebastian Reichel
<sebastian.reichel@collabora.com> wrote:
>
> As mentioned slightly out of patch context in the code, there
> is no reset routine for the chip. On boards where the chip is
> supplied by a fixed regulator, it might not even be resetted
> during (e.g. watchdog) reboot and can be in any state.
>
> If the device is probed with VAG enabled, the driver's probe
> routine will generate a loud pop sound when ANA_POWER is
> being programmed. Avoid this by properly disabling just the
> VAG bit and waiting the required power down time.
>
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

Reviewed-by: Fabio Estevam <festivem@gmail.com>
diff mbox series

Patch

diff --git a/sound/soc/codecs/sgtl5000.c b/sound/soc/codecs/sgtl5000.c
index d5130193b4a2..e8a8bf7b4ffe 100644
--- a/sound/soc/codecs/sgtl5000.c
+++ b/sound/soc/codecs/sgtl5000.c
@@ -1653,6 +1653,40 @@  static int sgtl5000_i2c_probe(struct i2c_client *client,
 		dev_err(&client->dev,
 			"Error %d initializing CHIP_CLK_CTRL\n", ret);
 
+	/* Mute everything to avoid pop from the following power-up */
+	ret = regmap_write(sgtl5000->regmap, SGTL5000_CHIP_ANA_CTRL,
+			   SGTL5000_CHIP_ANA_CTRL_DEFAULT);
+	if (ret) {
+		dev_err(&client->dev,
+			"Error %d muting outputs via CHIP_ANA_CTRL\n", ret);
+		goto disable_clk;
+	}
+
+	/*
+	 * If VAG is powered-on (e.g. from previous boot), it would be disabled
+	 * by the write to ANA_POWER in later steps of the probe code. This
+	 * may create a loud pop even with all outputs muted. The proper way
+	 * to circumvent this is disabling the bit first and waiting the proper
+	 * cool-down time.
+	 */
+	ret = regmap_read(sgtl5000->regmap, SGTL5000_CHIP_ANA_POWER, &value);
+	if (ret) {
+		dev_err(&client->dev, "Failed to read ANA_POWER: %d\n", ret);
+		goto disable_clk;
+	}
+	if (value & SGTL5000_VAG_POWERUP) {
+		ret = regmap_update_bits(sgtl5000->regmap,
+					 SGTL5000_CHIP_ANA_POWER,
+					 SGTL5000_VAG_POWERUP,
+					 0);
+		if (ret) {
+			dev_err(&client->dev, "Error %d disabling VAG\n", ret);
+			goto disable_clk;
+		}
+
+		msleep(SGTL5000_VAG_POWERDOWN_DELAY);
+	}
+
 	/* Follow section 2.2.1.1 of AN3663 */
 	ana_pwr = SGTL5000_ANA_POWER_DEFAULT;
 	if (sgtl5000->num_supplies <= VDDD) {
diff --git a/sound/soc/codecs/sgtl5000.h b/sound/soc/codecs/sgtl5000.h
index a4bf4bca95bf..56ec5863f250 100644
--- a/sound/soc/codecs/sgtl5000.h
+++ b/sound/soc/codecs/sgtl5000.h
@@ -233,6 +233,7 @@ 
 /*
  * SGTL5000_CHIP_ANA_CTRL
  */
+#define SGTL5000_CHIP_ANA_CTRL_DEFAULT		0x0133
 #define SGTL5000_LINE_OUT_MUTE			0x0100
 #define SGTL5000_HP_SEL_MASK			0x0040
 #define SGTL5000_HP_SEL_SHIFT			6