Commit 6b35f924 authored Jan 19, 2012 by Fabio Estevam Committed by Mark Brown Jan 20, 2012

ASoC: mxs: Fix mxs-saif timeout



On a mx28evk board the following errors happens on mxs-sgtl5000 probe:

[    0.660000] saif0_clk_set_rate: divider writing timeout
[    0.670000] mxs-sgtl5000: probe of mxs-sgtl5000.0 failed with error -110
[    0.670000] ALSA device list:
[    0.680000]   No soundcards found.

This timeout happens because clk_set_rate will result in writing to the DIV bits
of register HW_CLKCTRL_SAIF0 with the saif clock gated (CLKGATE bit set to one).

MX28 Reference states the following about CLKGATE:

"The DIV field can change ONLY when this clock gate bit field is low."

So call clk_prepare_enable prior to clk_set_rate to fix this problem.

After this change the mxs-saif driver can be correctly probed and audio is functional.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

parent fed22007

sound/soc/mxs/mxs-saif.c

+5 −0

Original line number	Diff line number	Diff line
		@@ -124,6 +124,8 @@ static int mxs_saif_set_clk(struct mxs_saif *saif,
		*
		* If MCLK is not used, we just set saif clk to 512*fs.
		*/
		clk_prepare_enable(master_saif->clk);

		if (master_saif->mclk_in_use) {
		if (mclk % 32 == 0) {
		scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
		@@ -133,6 +135,7 @@ static int mxs_saif_set_clk(struct mxs_saif *saif,
		ret = clk_set_rate(master_saif->clk, 384 * rate);
		} else {
		/* SAIF MCLK should be either 32x or 48x */
		clk_disable_unprepare(master_saif->clk);
		return -EINVAL;
		}
		} else {
		@@ -140,6 +143,8 @@ static int mxs_saif_set_clk(struct mxs_saif *saif,
		scr &= ~BM_SAIF_CTRL_BITCLK_BASE_RATE;
		}

		clk_disable_unprepare(master_saif->clk);

		if (ret)
		return ret;