Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Unverified Commit 8d5737a5 authored by Matthias Reichl's avatar Matthias Reichl Committed by Mark Brown
Browse files

ASoC: bcm2835: fix hw_params error when device is in prepared state 



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: default avatarMatthias Reichl <hias@horus.com>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 4fbd8d19

sound/soc/bcm/bcm2835-i2s.c

+14 −6
Original line number Diff line number Diff line
@@ -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 snd_pcm_substream *substream, 
	}



	/* Clock should only be set up here if CPU is clock master */

	if (bit_clock_master) {

	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 snd_pcm_substream *substream, 
	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