From 1f8e86a5ea59beba4aacf0a5f8f3b7cb8ac77371 Mon Sep 17 00:00:00 2001 From: Sugar Zhang Date: Mon, 3 Jul 2023 18:54:44 +0800 Subject: [PATCH] ASoC: rockchip: pdm: Fix clk glitch on runtime PM For controller which is managed by PD (power-domain), when PD off, the controller is reset to the default status, and the FRAC-DIV is a fixed value(1/20). Once the mclk is enabled, there are some high freq cycle leak, to fix this issue, we use the pinctrl-idle to block these cycles until the config has been come back to the normal state. Signed-off-by: Sugar Zhang Change-Id: I4e34129277cffa7bc443b6addfb1e26b70bf546e --- sound/soc/rockchip/rockchip_pdm.c | 41 +++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/sound/soc/rockchip/rockchip_pdm.c b/sound/soc/rockchip/rockchip_pdm.c index 1c998f4f5a33..f95cd3229f96 100644 --- a/sound/soc/rockchip/rockchip_pdm.c +++ b/sound/soc/rockchip/rockchip_pdm.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -48,6 +49,8 @@ struct rk_pdm_dev { struct regmap *regmap; struct snd_dmaengine_dai_dma_data capture_dma_data; struct reset_control *reset; + struct pinctrl *pinctrl; + struct pinctrl_state *clk_state; unsigned int start_delay_ms; unsigned int filter_delay_ms; enum rk_pdm_version version; @@ -723,6 +726,31 @@ static const struct snd_soc_component_driver rockchip_pdm_component = { .name = "rockchip-pdm", }; +static int rockchip_pdm_pinctrl_select_clk_state(struct device *dev) +{ + struct rk_pdm_dev *pdm = dev_get_drvdata(dev); + + if (IS_ERR_OR_NULL(pdm->pinctrl) || !pdm->clk_state) + return 0; + + /* + * A necessary delay to make sure the correct + * frac div has been applied when resume from + * power down. + */ + udelay(10); + + /* + * Must disable the clk to avoid clk glitch + * when pinctrl switch from gpio to pdm clk. + */ + clk_disable_unprepare(pdm->clk); + pinctrl_select_state(pdm->pinctrl, pdm->clk_state); + clk_prepare_enable(pdm->clk); + + return 0; +} + static int rockchip_pdm_runtime_suspend(struct device *dev) { struct rk_pdm_dev *pdm = dev_get_drvdata(dev); @@ -731,6 +759,8 @@ static int rockchip_pdm_runtime_suspend(struct device *dev) clk_disable_unprepare(pdm->clk); clk_disable_unprepare(pdm->hclk); + pinctrl_pm_select_idle_state(dev); + return 0; } @@ -755,6 +785,8 @@ static int rockchip_pdm_runtime_resume(struct device *dev) rockchip_pdm_rxctrl(pdm, 0); + rockchip_pdm_pinctrl_select_clk_state(dev); + return 0; err_regmap: @@ -936,6 +968,15 @@ static int rockchip_pdm_probe(struct platform_device *pdev) pdm->dev = &pdev->dev; dev_set_drvdata(&pdev->dev, pdm); + pdm->pinctrl = devm_pinctrl_get(&pdev->dev); + if (!IS_ERR_OR_NULL(pdm->pinctrl)) { + pdm->clk_state = pinctrl_lookup_state(pdm->pinctrl, "clk"); + if (IS_ERR(pdm->clk_state)) { + pdm->clk_state = NULL; + dev_dbg(pdm->dev, "Have no clk pinctrl state\n"); + } + } + pdm->start_delay_ms = PDM_START_DELAY_MS_DEFAULT; pdm->filter_delay_ms = PDM_FILTER_DELAY_MS_MIN;