diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.14/950-0161-ASoC-bcm2835-fix-hw_params-error-when-device-is-in-p.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.14/950-0161-ASoC-bcm2835-fix-hw_params-error-when-device-is-in-p.patch | 69 |
1 files changed, 69 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.14/950-0161-ASoC-bcm2835-fix-hw_params-error-when-device-is-in-p.patch b/target/linux/brcm2708/patches-4.14/950-0161-ASoC-bcm2835-fix-hw_params-error-when-device-is-in-p.patch new file mode 100644 index 0000000000..e94199288b --- /dev/null +++ b/target/linux/brcm2708/patches-4.14/950-0161-ASoC-bcm2835-fix-hw_params-error-when-device-is-in-p.patch @@ -0,0 +1,69 @@ +From 0f409e6c30a04eb85792a6883e81ad2af118c7bd Mon Sep 17 00:00:00 2001 +From: Matthias Reichl <github@hias.horus.com> +Date: Thu, 18 Jan 2018 12:36:44 +0100 +Subject: [PATCH 161/454] ASoC: bcm2835: fix hw_params error when device is in + prepared state (#2345) + +commit 8d5737a5f53902a916ee1e1cb248c9b8b883b2ea upstream. + +If bcm2835 is configured as bitclock master calling hw_params() +after prepare() fails with EBUSY. This also makes it impossible to +use bcm2835 in full duplex mode. + +The error is caused by the split clock setup: clk_set_rate +is called in hw_params, clk_prepare_enable in prepare. As hw_params +doesn't check if the clock was already enabled clk_set_rate +fails with EBUSY. + +Fix this by moving clock startup from prepare to hw_params and +let hw_params properly deal with an already set up or enabled +clock. + +Signed-off-by: Matthias Reichl <hias@horus.com> +--- + sound/soc/bcm/bcm2835-i2s.c | 20 ++++++++++++++------ + 1 file changed, 14 insertions(+), 6 deletions(-) + +--- a/sound/soc/bcm/bcm2835-i2s.c ++++ b/sound/soc/bcm/bcm2835-i2s.c +@@ -130,6 +130,7 @@ struct bcm2835_i2s_dev { + struct regmap *i2s_regmap; + struct clk *clk; + bool clk_prepared; ++ int clk_rate; + }; + + static void bcm2835_i2s_start_clock(struct bcm2835_i2s_dev *dev) +@@ -419,10 +420,19 @@ static int bcm2835_i2s_hw_params(struct + } + + /* Clock should only be set up here if CPU is clock master */ +- if (bit_clock_master) { +- ret = clk_set_rate(dev->clk, bclk_rate); +- if (ret) +- return ret; ++ if (bit_clock_master && ++ (!dev->clk_prepared || dev->clk_rate != bclk_rate)) { ++ if (dev->clk_prepared) ++ bcm2835_i2s_stop_clock(dev); ++ ++ if (dev->clk_rate != bclk_rate) { ++ ret = clk_set_rate(dev->clk, bclk_rate); ++ if (ret) ++ return ret; ++ dev->clk_rate = bclk_rate; ++ } ++ ++ bcm2835_i2s_start_clock(dev); + } + + /* Setup the frame format */ +@@ -618,8 +628,6 @@ static int bcm2835_i2s_prepare(struct sn + struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai); + uint32_t cs_reg; + +- bcm2835_i2s_start_clock(dev); +- + /* + * Clear both FIFOs if the one that should be started + * is not empty at the moment. This should only happen |