Add support of low power modes to STM32 SAI driver.
Signed-off-by: Olivier Moysan olivier.moysan@st.com --- sound/soc/stm/stm32_sai.c | 80 ++++++++++++++++++++++++++++++++++++++----- sound/soc/stm/stm32_sai.h | 2 ++ sound/soc/stm/stm32_sai_sub.c | 45 ++++++++++++++++++------ 3 files changed, 108 insertions(+), 19 deletions(-)
diff --git a/sound/soc/stm/stm32_sai.c b/sound/soc/stm/stm32_sai.c index d68d62f12df5..7550d5f08be3 100644 --- a/sound/soc/stm/stm32_sai.c +++ b/sound/soc/stm/stm32_sai.c @@ -21,6 +21,7 @@ #include <linux/delay.h> #include <linux/module.h> #include <linux/of_platform.h> +#include <linux/pinctrl/consumer.h> #include <linux/reset.h>
#include <sound/dmaengine_pcm.h> @@ -44,20 +45,41 @@ static const struct of_device_id stm32_sai_ids[] = { {} };
-static int stm32_sai_sync_conf_client(struct stm32_sai_data *sai, int synci) +static int stm32_sai_pclk_disable(struct device *dev) +{ + struct stm32_sai_data *sai = dev_get_drvdata(dev); + + clk_disable_unprepare(sai->pclk); + + return 0; +} + +static int stm32_sai_pclk_enable(struct device *dev) { + struct stm32_sai_data *sai = dev_get_drvdata(dev); int ret;
- /* Enable peripheral clock to allow GCR register access */ ret = clk_prepare_enable(sai->pclk); if (ret) { dev_err(&sai->pdev->dev, "failed to enable clock: %d\n", ret); return ret; }
+ return 0; +} + +static int stm32_sai_sync_conf_client(struct stm32_sai_data *sai, int synci) +{ + int ret; + + /* Enable peripheral clock to allow GCR register access */ + ret = stm32_sai_pclk_enable(&sai->pdev->dev); + if (ret) + return ret; + writel_relaxed(FIELD_PREP(SAI_GCR_SYNCIN_MASK, (synci - 1)), sai->base);
- clk_disable_unprepare(sai->pclk); + stm32_sai_pclk_disable(&sai->pdev->dev);
return 0; } @@ -68,11 +90,9 @@ static int stm32_sai_sync_conf_provider(struct stm32_sai_data *sai, int synco) int ret;
/* Enable peripheral clock to allow GCR register access */ - ret = clk_prepare_enable(sai->pclk); - if (ret) { - dev_err(&sai->pdev->dev, "failed to enable clock: %d\n", ret); + ret = stm32_sai_pclk_enable(&sai->pdev->dev); + if (ret) return ret; - }
dev_dbg(&sai->pdev->dev, "Set %pOFn%s as synchro provider\n", sai->pdev->dev.of_node, @@ -83,13 +103,13 @@ static int stm32_sai_sync_conf_provider(struct stm32_sai_data *sai, int synco) dev_err(&sai->pdev->dev, "%pOFn%s already set as sync provider\n", sai->pdev->dev.of_node, prev_synco == STM_SAI_SYNC_OUT_A ? "A" : "B"); - clk_disable_unprepare(sai->pclk); + stm32_sai_pclk_disable(&sai->pdev->dev); return -EINVAL; }
writel_relaxed(FIELD_PREP(SAI_GCR_SYNCOUT_MASK, synco), sai->base);
- clk_disable_unprepare(sai->pclk); + stm32_sai_pclk_disable(&sai->pdev->dev);
return 0; } @@ -195,12 +215,54 @@ static int stm32_sai_probe(struct platform_device *pdev) return devm_of_platform_populate(&pdev->dev); }
+#ifdef CONFIG_PM_SLEEP +/* + * When pins are shared by two sai sub instances, pins have to be defined + * in sai parent node. In this case, pins state is not managed by alsa fw. + * These pins are managed in suspend/resume callbacks. + */ +static int stm32_sai_suspend(struct device *dev) +{ + struct stm32_sai_data *sai = dev_get_drvdata(dev); + int ret; + + ret = stm32_sai_pclk_enable(dev); + if (ret) + return ret; + + sai->gcr = readl_relaxed(sai->base); + stm32_sai_pclk_disable(dev); + + return pinctrl_pm_select_sleep_state(dev); +} + +static int stm32_sai_resume(struct device *dev) +{ + struct stm32_sai_data *sai = dev_get_drvdata(dev); + int ret; + + ret = stm32_sai_pclk_enable(dev); + if (ret) + return ret; + + writel_relaxed(sai->gcr, sai->base); + stm32_sai_pclk_disable(dev); + + return pinctrl_pm_select_default_state(dev); +} +#endif /* CONFIG_PM_SLEEP */ + +static const struct dev_pm_ops stm32_sai_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(stm32_sai_suspend, stm32_sai_resume) +}; + MODULE_DEVICE_TABLE(of, stm32_sai_ids);
static struct platform_driver stm32_sai_driver = { .driver = { .name = "st,stm32-sai", .of_match_table = stm32_sai_ids, + .pm = &stm32_sai_pm_ops, }, .probe = stm32_sai_probe, }; diff --git a/sound/soc/stm/stm32_sai.h b/sound/soc/stm/stm32_sai.h index 08de899c766b..9c36a393ab7b 100644 --- a/sound/soc/stm/stm32_sai.h +++ b/sound/soc/stm/stm32_sai.h @@ -268,6 +268,7 @@ struct stm32_sai_conf { * @version: SOC version * @irq: SAI interrupt line * @set_sync: pointer to synchro mode configuration callback + * @gcr: SAI Global Configuration Register */ struct stm32_sai_data { struct platform_device *pdev; @@ -279,4 +280,5 @@ struct stm32_sai_data { int irq; int (*set_sync)(struct stm32_sai_data *sai, struct device_node *np_provider, int synco, int synci); + u32 gcr; }; diff --git a/sound/soc/stm/stm32_sai_sub.c b/sound/soc/stm/stm32_sai_sub.c index 55d802f51c15..2a90641cf164 100644 --- a/sound/soc/stm/stm32_sai_sub.c +++ b/sound/soc/stm/stm32_sai_sub.c @@ -168,6 +168,7 @@ static bool stm32_sai_sub_volatile_reg(struct device *dev, unsigned int reg) { switch (reg) { case STM_SAI_DR_REGX: + case STM_SAI_SR_REGX: return true; default: return false; @@ -182,7 +183,6 @@ static bool stm32_sai_sub_writeable_reg(struct device *dev, unsigned int reg) case STM_SAI_FRCR_REGX: case STM_SAI_SLOTR_REGX: case STM_SAI_IMR_REGX: - case STM_SAI_SR_REGX: case STM_SAI_CLRFR_REGX: case STM_SAI_DR_REGX: case STM_SAI_PDMCR_REGX: @@ -202,6 +202,7 @@ static const struct regmap_config stm32_sai_sub_regmap_config_f4 = { .volatile_reg = stm32_sai_sub_volatile_reg, .writeable_reg = stm32_sai_sub_writeable_reg, .fast_io = true, + .cache_type = REGCACHE_FLAT, };
static const struct regmap_config stm32_sai_sub_regmap_config_h7 = { @@ -213,6 +214,7 @@ static const struct regmap_config stm32_sai_sub_regmap_config_h7 = { .volatile_reg = stm32_sai_sub_volatile_reg, .writeable_reg = stm32_sai_sub_writeable_reg, .fast_io = true, + .cache_type = REGCACHE_FLAT, };
static int snd_pcm_iec958_info(struct snd_kcontrol *kcontrol, @@ -441,8 +443,8 @@ static irqreturn_t stm32_sai_isr(int irq, void *devid) if (!flags) return IRQ_NONE;
- regmap_update_bits(sai->regmap, STM_SAI_CLRFR_REGX, SAI_XCLRFR_MASK, - SAI_XCLRFR_MASK); + regmap_write_bits(sai->regmap, STM_SAI_CLRFR_REGX, SAI_XCLRFR_MASK, + SAI_XCLRFR_MASK);
if (!sai->substream) { dev_err(&pdev->dev, "Device stopped. Spurious IRQ 0x%x\n", sr); @@ -704,9 +706,8 @@ static int stm32_sai_startup(struct snd_pcm_substream *substream, }
/* Enable ITs */ - - regmap_update_bits(sai->regmap, STM_SAI_CLRFR_REGX, - SAI_XCLRFR_MASK, SAI_XCLRFR_MASK); + regmap_write_bits(sai->regmap, STM_SAI_CLRFR_REGX, + SAI_XCLRFR_MASK, SAI_XCLRFR_MASK);
imr = SAI_XIMR_OVRUDRIE; if (STM_SAI_IS_CAPTURE(sai)) { @@ -738,10 +739,10 @@ static int stm32_sai_set_config(struct snd_soc_dai *cpu_dai, * SAI fifo threshold is set to half fifo, to keep enough space * for DMA incoming bursts. */ - regmap_update_bits(sai->regmap, STM_SAI_CR2_REGX, - SAI_XCR2_FFLUSH | SAI_XCR2_FTH_MASK, - SAI_XCR2_FFLUSH | - SAI_XCR2_FTH_SET(STM_SAI_FIFO_TH_HALF)); + regmap_write_bits(sai->regmap, STM_SAI_CR2_REGX, + SAI_XCR2_FFLUSH | SAI_XCR2_FTH_MASK, + SAI_XCR2_FFLUSH | + SAI_XCR2_FTH_SET(STM_SAI_FIFO_TH_HALF));
/* DS bits in CR1 not set for SPDIF (size forced to 24 bits).*/ if (STM_SAI_PROTOCOL_IS_SPDIF(sai)) { @@ -1492,10 +1493,34 @@ static int stm32_sai_sub_probe(struct platform_device *pdev) return 0; }
+#ifdef CONFIG_PM_SLEEP +static int stm32_sai_sub_suspend(struct device *dev) +{ + struct stm32_sai_sub_data *sai = dev_get_drvdata(dev); + + regcache_cache_only(sai->regmap, true); + regcache_mark_dirty(sai->regmap); + return 0; +} + +static int stm32_sai_sub_resume(struct device *dev) +{ + struct stm32_sai_sub_data *sai = dev_get_drvdata(dev); + + regcache_cache_only(sai->regmap, false); + return regcache_sync(sai->regmap); +} +#endif /* CONFIG_PM_SLEEP */ + +static const struct dev_pm_ops stm32_sai_sub_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(stm32_sai_sub_suspend, stm32_sai_sub_resume) +}; + static struct platform_driver stm32_sai_sub_driver = { .driver = { .name = "st,stm32-sai-sub", .of_match_table = stm32_sai_sub_ids, + .pm = &stm32_sai_sub_pm_ops, }, .probe = stm32_sai_sub_probe, };