1 From b10789f9366de21dc44df087c4e65aa4a56a1dd9 Mon Sep 17 00:00:00 2001
2 From: Matthias Reichl <hias@horus.com>
3 Date: Sun, 11 Oct 2015 15:25:51 +0200
4 Subject: [PATCH 016/304] bcm2835-i2s: setup clock only if CPU is clock master
6 Code ported from bcm2708-i2s driver in Raspberry Pi tree.
8 RPi commit c14827ecdaa36607f6110f9ce8df96e698672191 ("bcm2708: Allow
9 option card devices to be configured via DT")
11 Original work by Zoltan Szenczi, committed to RPi tree by
14 Signed-off-by: Matthias Reichl <hias@horus.com>
16 sound/soc/bcm/bcm2835-i2s.c | 28 +++++++++++++++++++---------
17 1 file changed, 19 insertions(+), 9 deletions(-)
19 --- a/sound/soc/bcm/bcm2835-i2s.c
20 +++ b/sound/soc/bcm/bcm2835-i2s.c
21 @@ -411,15 +411,25 @@ static int bcm2835_i2s_hw_params(struct
22 divf = dividend & BCM2835_CLK_DIVF_MASK;
25 - /* Set clock divider */
26 - regmap_write(dev->clk_regmap, BCM2835_CLK_PCMDIV_REG, BCM2835_CLK_PASSWD
27 - | BCM2835_CLK_DIVI(divi)
28 - | BCM2835_CLK_DIVF(divf));
29 + /* Clock should only be set up here if CPU is clock master */
30 + switch (dev->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
31 + case SND_SOC_DAIFMT_CBS_CFS:
32 + case SND_SOC_DAIFMT_CBS_CFM:
33 + /* Set clock divider */
34 + regmap_write(dev->clk_regmap, BCM2835_CLK_PCMDIV_REG,
36 + | BCM2835_CLK_DIVI(divi)
37 + | BCM2835_CLK_DIVF(divf));
39 - /* Setup clock, but don't start it yet */
40 - regmap_write(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG, BCM2835_CLK_PASSWD
41 - | BCM2835_CLK_MASH(mash)
42 - | BCM2835_CLK_SRC(clk_src));
43 + /* Setup clock, but don't start it yet */
44 + regmap_write(dev->clk_regmap, BCM2835_CLK_PCMCTL_REG,
46 + | BCM2835_CLK_MASH(mash)
47 + | BCM2835_CLK_SRC(clk_src));
53 /* Setup the frame format */
54 format = BCM2835_I2S_CHEN;