[alsa-devel] Applied "ASoC: fsl_ssi: Add driver suspend and resume to support MEGA Fast" to the asoc tree

[Mark Brown]

The patch

   ASoC: fsl_ssi: Add driver suspend and resume to support MEGA Fast

has been applied to the asoc tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

>From 05cf237972fe65eb537ea4f10e5627ceeb8f89b6 Mon Sep 17 00:00:00 2001
From: Zidan Wang <zidan.wang at freescale.com>
Date: Fri, 18 Sep 2015 11:09:12 +0800
Subject: [PATCH] ASoC: fsl_ssi: Add driver suspend and resume to support MEGA
 Fast

For i.MX6 SoloX, there is a mode of the SoC to shutdown all power
source of modules during system suspend and resume procedure. Thus,
SSI needs to save all the values of registers before the system
suspend and restore them after the system resume.

The register SFCSR is volatile, but some bits in it need to be
recovered after suspend/resume.

Signed-off-by: Zidan Wang <zidan.wang at freescale.com>
Acked-by: Nicolin Chen <nicoleotsuka at gmail.com>
Signed-off-by: Mark Brown <broonie at kernel.org>
---
 sound/soc/fsl/fsl_ssi.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 102 insertions(+)

diff --git a/sound/soc/fsl/fsl_ssi.c b/sound/soc/fsl/fsl_ssi.c
index 8ec6fb2..7c495d3 100644
--- a/sound/soc/fsl/fsl_ssi.c
+++ b/sound/soc/fsl/fsl_ssi.c
@@ -111,12 +111,75 @@ struct fsl_ssi_rxtx_reg_val {
 	struct fsl_ssi_reg_val rx;
 	struct fsl_ssi_reg_val tx;
 };
+
+static const struct reg_default fsl_ssi_reg_defaults[] = {
+	{0x10, 0x00000000},
+	{0x18, 0x00003003},
+	{0x1c, 0x00000200},
+	{0x20, 0x00000200},
+	{0x24, 0x00040000},
+	{0x28, 0x00040000},
+	{0x38, 0x00000000},
+	{0x48, 0x00000000},
+	{0x4c, 0x00000000},
+	{0x54, 0x00000000},
+	{0x58, 0x00000000},
+};
+
+static bool fsl_ssi_readable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case CCSR_SSI_SACCEN:
+	case CCSR_SSI_SACCDIS:
+		return false;
+	default:
+		return true;
+	}
+}
+
+static bool fsl_ssi_volatile_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case CCSR_SSI_STX0:
+	case CCSR_SSI_STX1:
+	case CCSR_SSI_SRX0:
+	case CCSR_SSI_SRX1:
+	case CCSR_SSI_SISR:
+	case CCSR_SSI_SFCSR:
+	case CCSR_SSI_SACADD:
+	case CCSR_SSI_SACDAT:
+	case CCSR_SSI_SATAG:
+	case CCSR_SSI_SACCST:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static bool fsl_ssi_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case CCSR_SSI_SRX0:
+	case CCSR_SSI_SRX1:
+	case CCSR_SSI_SACCST:
+		return false;
+	default:
+		return true;
+	}
+}
+
 static const struct regmap_config fsl_ssi_regconfig = {
 	.max_register = CCSR_SSI_SACCDIS,
 	.reg_bits = 32,
 	.val_bits = 32,
 	.reg_stride = 4,
 	.val_format_endian = REGMAP_ENDIAN_NATIVE,
+	.reg_defaults = fsl_ssi_reg_defaults,
+	.num_reg_defaults = ARRAY_SIZE(fsl_ssi_reg_defaults),
+	.readable_reg = fsl_ssi_readable_reg,
+	.volatile_reg = fsl_ssi_volatile_reg,
+	.writeable_reg = fsl_ssi_writeable_reg,
+	.cache_type = REGCACHE_RBTREE,
 };
 
 struct fsl_ssi_soc_data {
@@ -176,6 +239,9 @@ struct fsl_ssi_private {
 	unsigned int baudclk_streams;
 	unsigned int bitclk_freq;
 
+	/*regcache for SFCSR*/
+	u32 regcache_sfcsr;
+
 	/* DMA params */
 	struct snd_dmaengine_dai_dma_data dma_params_tx;
 	struct snd_dmaengine_dai_dma_data dma_params_rx;
@@ -1513,10 +1579,46 @@ static int fsl_ssi_remove(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int fsl_ssi_suspend(struct device *dev)
+{
+	struct fsl_ssi_private *ssi_private = dev_get_drvdata(dev);
+	struct regmap *regs = ssi_private->regs;
+
+	regmap_read(regs, CCSR_SSI_SFCSR,
+			&ssi_private->regcache_sfcsr);
+
+	regcache_cache_only(regs, true);
+	regcache_mark_dirty(regs);
+
+	return 0;
+}
+
+static int fsl_ssi_resume(struct device *dev)
+{
+	struct fsl_ssi_private *ssi_private = dev_get_drvdata(dev);
+	struct regmap *regs = ssi_private->regs;
+
+	regcache_cache_only(regs, false);
+
+	regmap_update_bits(regs, CCSR_SSI_SFCSR,
+			CCSR_SSI_SFCSR_RFWM1_MASK | CCSR_SSI_SFCSR_TFWM1_MASK |
+			CCSR_SSI_SFCSR_RFWM0_MASK | CCSR_SSI_SFCSR_TFWM0_MASK,
+			ssi_private->regcache_sfcsr);
+
+	return regcache_sync(regs);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct dev_pm_ops fsl_ssi_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(fsl_ssi_suspend, fsl_ssi_resume)
+};
+
 static struct platform_driver fsl_ssi_driver = {
 	.driver = {
 		.name = "fsl-ssi-dai",
 		.of_match_table = fsl_ssi_ids,
+		.pm = &fsl_ssi_pm,
 	},
 	.probe = fsl_ssi_probe,
 	.remove = fsl_ssi_remove,
-- 
2.5.0