On 21/06/19 9:12 AM, Baolin Wang wrote:
> For Spreadtrum SD card voltage switching, besides regulator setting,
> it also need switch related pin's state to output corresponding voltage.
>
> This patch adds pin control operation to support voltage switch.
>
> Signed-off-by: Baolin Wang <baolin.w...@linaro.org>
Acked-by: Adrian Hunter <adrian.hun...@intel.com>
> ---
> drivers/mmc/host/sdhci-sprd.c | 54
> +++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 54 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-sprd.c b/drivers/mmc/host/sdhci-sprd.c
> index 8b23c88..6ee340a 100644
> --- a/drivers/mmc/host/sdhci-sprd.c
> +++ b/drivers/mmc/host/sdhci-sprd.c
> @@ -12,6 +12,7 @@
> #include <linux/of.h>
> #include <linux/of_device.h>
> #include <linux/of_gpio.h>
> +#include <linux/pinctrl/consumer.h>
> #include <linux/platform_device.h>
> #include <linux/pm_runtime.h>
> #include <linux/regulator/consumer.h>
> @@ -72,6 +73,9 @@ struct sdhci_sprd_host {
> struct clk *clk_sdio;
> struct clk *clk_enable;
> struct clk *clk_2x_enable;
> + struct pinctrl *pinctrl;
> + struct pinctrl_state *pins_uhs;
> + struct pinctrl_state *pins_default;
> u32 base_rate;
> int flags; /* backup of host attribute */
> u32 phy_delay[MMC_TIMING_MMC_HS400 + 2];
> @@ -405,6 +409,8 @@ static void sdhci_sprd_request(struct mmc_host *mmc,
> struct mmc_request *mrq)
>
> static int sdhci_sprd_voltage_switch(struct mmc_host *mmc, struct mmc_ios
> *ios)
> {
> + struct sdhci_host *host = mmc_priv(mmc);
> + struct sdhci_sprd_host *sprd_host = TO_SPRD_HOST(host);
> int ret;
>
> if (!IS_ERR(mmc->supply.vqmmc)) {
> @@ -416,6 +422,37 @@ static int sdhci_sprd_voltage_switch(struct mmc_host
> *mmc, struct mmc_ios *ios)
> }
> }
>
> + if (IS_ERR(sprd_host->pinctrl))
> + return 0;
> +
> + switch (ios->signal_voltage) {
> + case MMC_SIGNAL_VOLTAGE_180:
> + ret = pinctrl_select_state(sprd_host->pinctrl,
> + sprd_host->pins_uhs);
> + if (ret) {
> + pr_err("%s: failed to select uhs pin state\n",
> + mmc_hostname(mmc));
> + return ret;
> + }
> + break;
> +
> + default:
> + /* fall-through */
> + case MMC_SIGNAL_VOLTAGE_330:
> + ret = pinctrl_select_state(sprd_host->pinctrl,
> + sprd_host->pins_default);
> + if (ret) {
> + pr_err("%s: failed to select default pin state\n",
> + mmc_hostname(mmc));
> + return ret;
> + }
> + break;
> + }
> +
> + /* Wait for 300 ~ 500 us for pin state stable */
> + usleep_range(300, 500);
> + sdhci_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
> +
> return 0;
> }
>
> @@ -504,6 +541,23 @@ static int sdhci_sprd_probe(struct platform_device *pdev)
> sprd_host = TO_SPRD_HOST(host);
> sdhci_sprd_phy_param_parse(sprd_host, pdev->dev.of_node);
>
> + sprd_host->pinctrl = devm_pinctrl_get(&pdev->dev);
> + if (!IS_ERR(sprd_host->pinctrl)) {
> + sprd_host->pins_uhs =
> + pinctrl_lookup_state(sprd_host->pinctrl, "state_uhs");
> + if (IS_ERR(sprd_host->pins_uhs)) {
> + ret = PTR_ERR(sprd_host->pins_uhs);
> + goto pltfm_free;
> + }
> +
> + sprd_host->pins_default =
> + pinctrl_lookup_state(sprd_host->pinctrl, "default");
> + if (IS_ERR(sprd_host->pins_default)) {
> + ret = PTR_ERR(sprd_host->pins_default);
> + goto pltfm_free;
> + }
> + }
> +
> clk = devm_clk_get(&pdev->dev, "sdio");
> if (IS_ERR(clk)) {
> ret = PTR_ERR(clk);
>
