From df91bc23dcb052ff2da71b3482bf3c5fbf4b8a53 Mon Sep 17 00:00:00 2001 From: Clemens Ladisch Date: Fri, 29 Aug 2008 13:08:34 +0200 Subject: [PATCH] ALSA: oxygen: fix distorted output on AK4396-based cards When changing the sample rate, the CMI8788's master clock output becomes unstable for a short time. The AK4396 needs the master clock to do SPI writes, so writing to an AK4396 control register directly after a sample rate change will garble the value. In our case, this leads to the DACs being misconfigured to I2S sample format, which results in a wrong output level and horrible distortions on samples louder than -6 dB. To fix this, we need to wait until the new master clock signal has become stable before doing SPI writes. Signed-off-by: Clemens Ladisch Signed-off-by: Takashi Iwai --- sound/pci/oxygen/hifier.c | 4 ++++ sound/pci/oxygen/oxygen.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/sound/pci/oxygen/hifier.c b/sound/pci/oxygen/hifier.c index 7442460583dd..dad393ae040a 100644 --- a/sound/pci/oxygen/hifier.c +++ b/sound/pci/oxygen/hifier.c @@ -17,6 +17,7 @@ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ +#include #include #include #include @@ -107,6 +108,9 @@ static void set_ak4396_params(struct oxygen *chip, else value |= AK4396_DFS_QUAD; data->ak4396_ctl2 = value; + + msleep(1); /* wait for the new MCLK to become stable */ + ak4396_write(chip, AK4396_CONTROL_1, AK4396_DIF_24_MSB); ak4396_write(chip, AK4396_CONTROL_2, value); ak4396_write(chip, AK4396_CONTROL_1, AK4396_DIF_24_MSB | AK4396_RSTN); diff --git a/sound/pci/oxygen/oxygen.c b/sound/pci/oxygen/oxygen.c index 7c8ae31eb468..c5829d30ef86 100644 --- a/sound/pci/oxygen/oxygen.c +++ b/sound/pci/oxygen/oxygen.c @@ -28,6 +28,7 @@ * GPIO 1 -> DFS1 of AK5385 */ +#include #include #include #include @@ -213,6 +214,9 @@ static void set_ak4396_params(struct oxygen *chip, else value |= AK4396_DFS_QUAD; data->ak4396_ctl2 = value; + + msleep(1); /* wait for the new MCLK to become stable */ + for (i = 0; i < 4; ++i) { ak4396_write(chip, i, AK4396_CONTROL_1, AK4396_DIF_24_MSB); -- 2.20.1