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From 2165ae346e98922f21ffe6abad1f6d4226e445b1 Mon Sep 17 00:00:00 2001
From: Matthias Reichl <hias@horus.com>
Date: Sun, 11 Oct 2015 15:25:51 +0200
Subject: [PATCH] bcm2835-i2s: setup clock only if CPU is clock master
Code ported from bcm2708-i2s driver in Raspberry Pi tree.
RPi commit c14827ecdaa36607f6110f9ce8df96e698672191 ("bcm2708: Allow
option card devices to be configured via DT")
Original work by Zoltan Szenczi, committed to RPi tree by
Phil Elwell.
Signed-off-by: Matthias Reichl <hias@horus.com>
---
sound/soc/bcm/bcm2835-i2s.c | 28 +++++++++++++++++++---------
1 file changed, 19 insertions(+), 9 deletions(-)
--- a/sound/soc/bcm/bcm2835-i2s.c
+++ b/sound/soc/bcm/bcm2835-i2s.c
@@ -411,15 +411,25 @@ static int bcm2835_i2s_hw_params(struct
divf = dividend & BCM2835_CLK_DIVF_MASK;
}
- /* Set clock divider */
- regmap_write(dev->clk_regmap, BCM2835_CLK_PCMDIV_REG, BCM2835_CLK_PASSWD
- | BCM2835_CLK_DIVI(divi)
- | BCM2835_CLK_DIVF(divf));
+ /* Clock should only be set up here if CPU is clock master */
+ switch (dev->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
+ case SND_SOC_DAIFMT_CBS_CFS:
+ case SND_SOC_DAIFMT_CBS_CFM:
+ /* Set clock divider */
+ regmap_write(dev->clk_regmap, BCM2835_CLK_PCMDIV_REG,
+ BCM2835_CLK_PASSWD
+ | BCM2835_CLK_DIVI(divi)
+ | BCM2835_CLK_DIVF(divf));
- /* Setup clock, but don't start it yet */
- regmap_write(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG, BCM2835_CLK_PASSWD
- | BCM2835_CLK_MASH(mash)
- | BCM2835_CLK_SRC(clk_src));
+ /* Setup clock, but don't start it yet */
+ regmap_write(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG,
+ BCM2835_CLK_PASSWD
+ | BCM2835_CLK_MASH(mash)
+ | BCM2835_CLK_SRC(clk_src));
+ break;
+ default:
+ break;
+ }
/* Setup the frame format */
format = BCM2835_I2S_CHEN;
|
