[alsa-devel] [PATCH] ASoC: nau8825: reduce standby power consumption
Decrease internal clock frequency for power saving when standby. But clock divider needs restore when MCLK as system clock in playback.
Signed-off-by: John Hsu KCHSU0@nuvoton.com --- sound/soc/codecs/nau8825.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/sound/soc/codecs/nau8825.c b/sound/soc/codecs/nau8825.c index 3e7bee2..4c8572c 100644 --- a/sound/soc/codecs/nau8825.c +++ b/sound/soc/codecs/nau8825.c @@ -1116,6 +1116,9 @@ static int nau8825_configure_sysclk(struct nau8825 *nau8825, int clk_id, regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, NAU8825_CLK_SRC_MASK, NAU8825_CLK_SRC_MCLK); regmap_update_bits(regmap, NAU8825_REG_FLL6, NAU8825_DCO_EN, 0); + /* MCLK not changed by clock tree */ + regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, + NAU8825_CLK_MCLK_SRC_MASK, 0); ret = nau8825_mclk_prepare(nau8825, freq); if (ret) return ret; @@ -1126,6 +1129,13 @@ static int nau8825_configure_sysclk(struct nau8825 *nau8825, int clk_id, NAU8825_DCO_EN); regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, NAU8825_CLK_SRC_MASK, NAU8825_CLK_SRC_VCO); + /* Decrease the VCO frequency for power saving */ + regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, + NAU8825_CLK_MCLK_SRC_MASK, 0xf); + regmap_update_bits(regmap, NAU8825_REG_FLL1, + NAU8825_FLL_RATIO_MASK, 0x10); + regmap_update_bits(regmap, NAU8825_REG_FLL6, + NAU8825_SDM_EN, NAU8825_SDM_EN); if (nau8825->mclk_freq) { clk_disable_unprepare(nau8825->mclk); nau8825->mclk_freq = 0;
On Tue, Mar 22, 2016 at 11:57:05AM +0800, John Hsu wrote:
@@ -1116,6 +1116,9 @@ static int nau8825_configure_sysclk(struct nau8825 *nau8825, int clk_id, regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, NAU8825_CLK_SRC_MASK, NAU8825_CLK_SRC_MCLK); regmap_update_bits(regmap, NAU8825_REG_FLL6, NAU8825_DCO_EN, 0);
/* MCLK not changed by clock tree */regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER,NAU8825_CLK_MCLK_SRC_MASK, 0);
I'm going to apply this since I suspect there are already similar assumptions in the code but it does look like the issues Ben raised with one of your other patches with confusing sysclk management and overall device power might apply here. We can't rely on people changing the clock configuration in lower power modes.
Hi, On 3/29/2016 3:05 AM, Mark Brown wrote:
On Tue, Mar 22, 2016 at 11:57:05AM +0800, John Hsu wrote:
@@ -1116,6 +1116,9 @@ static int nau8825_configure_sysclk(struct nau8825 *nau8825, int clk_id, regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, NAU8825_CLK_SRC_MASK, NAU8825_CLK_SRC_MCLK); regmap_update_bits(regmap, NAU8825_REG_FLL6, NAU8825_DCO_EN, 0);
/* MCLK not changed by clock tree */regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER,NAU8825_CLK_MCLK_SRC_MASK, 0);I'm going to apply this since I suspect there are already similar assumptions in the code but it does look like the issues Ben raised with one of your other patches with confusing sysclk management and overall device power might apply here. We can't rely on people changing the clock configuration in lower power modes.
If the platform has internal clock for interrupt, the codec power should use less power as possible. The patch is made to guarantee that requirement. The system has better power saving by slowing down the internal clock.
The patch
ASoC: nau8825: reduce standby power consumption
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 5a78e7c37d5d27702fdc019d610361c95491f989 Mon Sep 17 00:00:00 2001
From: John Hsu KCHSU0@nuvoton.com Date: Tue, 22 Mar 2016 11:57:05 +0800 Subject: [PATCH] ASoC: nau8825: reduce standby power consumption
Decrease internal clock frequency for power saving when standby. But clock divider needs restore when MCLK as system clock in playback.
Signed-off-by: John Hsu KCHSU0@nuvoton.com Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/codecs/nau8825.c | 10 ++++++++++ 1 file changed, 10 insertions(+)
diff --git a/sound/soc/codecs/nau8825.c b/sound/soc/codecs/nau8825.c index 3e7bee29eed4..4c8572cdec94 100644 --- a/sound/soc/codecs/nau8825.c +++ b/sound/soc/codecs/nau8825.c @@ -1116,6 +1116,9 @@ static int nau8825_configure_sysclk(struct nau8825 *nau8825, int clk_id, regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, NAU8825_CLK_SRC_MASK, NAU8825_CLK_SRC_MCLK); regmap_update_bits(regmap, NAU8825_REG_FLL6, NAU8825_DCO_EN, 0); + /* MCLK not changed by clock tree */ + regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, + NAU8825_CLK_MCLK_SRC_MASK, 0); ret = nau8825_mclk_prepare(nau8825, freq); if (ret) return ret; @@ -1126,6 +1129,13 @@ static int nau8825_configure_sysclk(struct nau8825 *nau8825, int clk_id, NAU8825_DCO_EN); regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, NAU8825_CLK_SRC_MASK, NAU8825_CLK_SRC_VCO); + /* Decrease the VCO frequency for power saving */ + regmap_update_bits(regmap, NAU8825_REG_CLK_DIVIDER, + NAU8825_CLK_MCLK_SRC_MASK, 0xf); + regmap_update_bits(regmap, NAU8825_REG_FLL1, + NAU8825_FLL_RATIO_MASK, 0x10); + regmap_update_bits(regmap, NAU8825_REG_FLL6, + NAU8825_SDM_EN, NAU8825_SDM_EN); if (nau8825->mclk_freq) { clk_disable_unprepare(nau8825->mclk); nau8825->mclk_freq = 0;
participants (2)
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John Hsu -
Mark Brown