diff options
| author | Chris Brandt <chris.brandt@renesas.com> | 2017-01-25 15:28:08 -0500 |
|---|---|---|
| committer | Ulf Hansson <ulf.hansson@linaro.org> | 2017-02-13 13:20:41 +0100 |
| commit | 34a1654706c6cc20e7a9077063b307afe28ec66c (patch) | |
| tree | 8bf9e7a2407575ec379e86340f823f91a9f57025 /drivers | |
| parent | dc012058d79aa781d74988c83e29a7398ad1e47b (diff) | |
mmc: sh_mobile_sdhi: add support for 2 clocks
Some controllers have 2 clock sources instead of 1. The 2nd clock
is for the internal card detect logic and must be enabled/disabled
along with the main core clock for proper operation.
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/mmc/host/sh_mobile_sdhi.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/mmc/host/sh_mobile_sdhi.c b/drivers/mmc/host/sh_mobile_sdhi.c index 8bebf35c7576..bc6be0dbea39 100644 --- a/drivers/mmc/host/sh_mobile_sdhi.c +++ b/drivers/mmc/host/sh_mobile_sdhi.c @@ -143,6 +143,7 @@ MODULE_DEVICE_TABLE(of, sh_mobile_sdhi_of_match); struct sh_mobile_sdhi { struct clk *clk; + struct clk *clk_cd; struct tmio_mmc_data mmc_data; struct tmio_mmc_dma dma_priv; struct pinctrl *pinctrl; @@ -190,6 +191,12 @@ static int sh_mobile_sdhi_clk_enable(struct tmio_mmc_host *host) if (ret < 0) return ret; + ret = clk_prepare_enable(priv->clk_cd); + if (ret < 0) { + clk_disable_unprepare(priv->clk); + return ret; + } + /* * The clock driver may not know what maximum frequency * actually works, so it should be set with the max-frequency @@ -255,6 +262,7 @@ static void sh_mobile_sdhi_clk_disable(struct tmio_mmc_host *host) struct sh_mobile_sdhi *priv = host_to_priv(host); clk_disable_unprepare(priv->clk); + clk_disable_unprepare(priv->clk_cd); } static int sh_mobile_sdhi_card_busy(struct mmc_host *mmc) @@ -572,6 +580,21 @@ static int sh_mobile_sdhi_probe(struct platform_device *pdev) goto eprobe; } + /* + * Some controllers provide a 2nd clock just to run the internal card + * detection logic. Unfortunately, the existing driver architecture does + * not support a separation of clocks for runtime PM usage. When + * native hotplug is used, the tmio driver assumes that the core + * must continue to run for card detect to stay active, so we cannot + * disable it. + * Additionally, it is prohibited to supply a clock to the core but not + * to the card detect circuit. That leaves us with if separate clocks + * are presented, we must treat them both as virtually 1 clock. + */ + priv->clk_cd = devm_clk_get(&pdev->dev, "cd"); + if (IS_ERR(priv->clk_cd)) + priv->clk_cd = NULL; + priv->pinctrl = devm_pinctrl_get(&pdev->dev); if (!IS_ERR(priv->pinctrl)) { priv->pins_default = pinctrl_lookup_state(priv->pinctrl, |