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ASoC: qcom: Specify LE device endianness

PATCH In review Stephen Boyd 2 participants 2 messages Nov 20, 2015 – Nov 21, 2015

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PATCH 1/1 ASoC: qcom: Specify LE device endianness

This is a little endian device, but so far we've been relying on the regmap mmio bus handling this for us without explicitly stating that fact. After commit 4a98da2164cf (regmap-mmio: Use native endianness for read/write, 2015-10-29), the regmap mmio bus will read/write with the __raw_*() IO accessors, instead of using the readl/writel() APIs that do proper byte swapping for little endian devices.

So if we're running on a big endian processor and haven't specified the endianness explicitly in the regmap config or in DT, we're going to switch from doing little endian byte swapping to big endian accesses without byte swapping, leading to some confusing results. Specify the endianness explicitly so that the regmap core properly byte swaps the accesses for us.

Cc Kenneth Westfield <[email protected]>
Cc Kevin Hilman <[email protected]>
Cc Tyler Baker <[email protected]>
Cc Simon Arlott <[email protected]>
---
 sound/soc/qcom/lpass-cpu.c | 1 +
 1 file changed, 1 insertion(+)
sound/soc/qcom/lpass-cpu.c +1 -0
index e5101e0d2d37..00b6c9d039cf 100644
@@ -355,6 +355,7 @@ static struct regmap_config lpass_cpu_regmap_config = {
 	.readable_reg = lpass_cpu_regmap_readable,
 	.volatile_reg = lpass_cpu_regmap_volatile,
 	.cache_type = REGCACHE_FLAT,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
 };
 
 int asoc_qcom_lpass_cpu_platform_probe(struct platform_device *pdev)
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Applied "ASoC: qcom: Specify LE device endianness" to the asoc tree

The patch

ASoC: qcom: Specify LE device endianness

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

Quoted 1 line

From 18560a4e3b07438113b50589e78532d95f907029 Mon Sep 17 00:00:00 2001

From: Stephen Boyd <[email protected]>
Date: Fri, 20 Nov 2015 15:43:06 -0800
Subject: [PATCH] ASoC: qcom: Specify LE device endianness

This is a little endian device, but so far we've been relying on the regmap mmio bus handling this for us without explicitly stating that fact. After commit 4a98da2164cf (regmap-mmio: Use native endianness for read/write, 2015-10-29), the regmap mmio bus will read/write with the __raw_*() IO accessors, instead of using the readl/writel() APIs that do proper byte swapping for little endian devices.

So if we're running on a big endian processor and haven't specified the endianness explicitly in the regmap config or in DT, we're going to switch from doing little endian byte swapping to big endian accesses without byte swapping, leading to some confusing results. Specify the endianness explicitly so that the regmap core properly byte swaps the accesses for us.

Cc Kenneth Westfield <[email protected]>
Cc Kevin Hilman <[email protected]>
Cc Tyler Baker <[email protected]>
Cc Simon Arlott <[email protected]>
---
 sound/soc/qcom/lpass-cpu.c | 1 +
 1 file changed, 1 insertion(+)
sound/soc/qcom/lpass-cpu.c +1 -0
index e5101e0..00b6c9d 100644
@@ -355,6 +355,7 @@ static struct regmap_config lpass_cpu_regmap_config = {
 	.readable_reg = lpass_cpu_regmap_readable,
 	.volatile_reg = lpass_cpu_regmap_volatile,
 	.cache_type = REGCACHE_FLAT,
+	.val_format_endian = REGMAP_ENDIAN_LITTLE,
 };
 
 int asoc_qcom_lpass_cpu_platform_probe(struct platform_device *pdev)
Signature · 1 line
2.6.1