From 00a97fc57c09ff1cf71107753d9b5629caeb8c8a Mon Sep 17 00:00:00 2001 From: Iker Pedrosa Date: Mon, 11 May 2026 10:53:58 +0200 Subject: [PATCH] mmc: sdhci-of-k1: add regulator and pinctrl voltage switching support Add voltage switching infrastructure for UHS-I modes by integrating both regulator framework (for supply voltage control) and pinctrl state switching (for pin drive strength optimization). - Add regulator supply parsing and voltage switching callback - Add optional pinctrl state switching between "default" (3.3V) and "state_uhs" (1.8V) configurations - Enable coordinated voltage and pin configuration changes for UHS modes This provides complete voltage switching support while maintaining backward compatibility when pinctrl states are not defined. Tested-by: Anand Moon Tested-by: Trevor Gamblin Acked-by: Adrian Hunter Reviewed-by: Troy Mitchell Tested-by: Vincent Legoll Signed-off-by: Iker Pedrosa Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-of-k1.c | 72 ++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) diff --git a/drivers/mmc/host/sdhci-of-k1.c b/drivers/mmc/host/sdhci-of-k1.c index 0dd06fc19b857..d9144537032a5 100644 --- a/drivers/mmc/host/sdhci-of-k1.c +++ b/drivers/mmc/host/sdhci-of-k1.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include "sdhci.h" @@ -71,6 +72,9 @@ struct spacemit_sdhci_host { struct clk *clk_core; struct clk *clk_io; + struct pinctrl *pinctrl; + struct pinctrl_state *pinctrl_default; + struct pinctrl_state *pinctrl_uhs; }; /* All helper functions will update clr/set while preserve rest bits */ @@ -219,6 +223,46 @@ static void spacemit_sdhci_pre_hs400_to_hs200(struct mmc_host *mmc) SPACEMIT_SDHC_PHY_CTRL_REG); } +static int spacemit_sdhci_start_signal_voltage_switch(struct mmc_host *mmc, + struct mmc_ios *ios) +{ + struct sdhci_host *host = mmc_priv(mmc); + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); + struct spacemit_sdhci_host *sdhst = sdhci_pltfm_priv(pltfm_host); + struct pinctrl_state *state; + int ret; + + ret = sdhci_start_signal_voltage_switch(mmc, ios); + if (ret) + return ret; + + if (!sdhst->pinctrl) + return 0; + + /* Select appropriate pinctrl state based on signal voltage */ + switch (ios->signal_voltage) { + case MMC_SIGNAL_VOLTAGE_330: + state = sdhst->pinctrl_default; + break; + case MMC_SIGNAL_VOLTAGE_180: + state = sdhst->pinctrl_uhs; + break; + default: + dev_warn(mmc_dev(mmc), "unsupported voltage %d\n", ios->signal_voltage); + return 0; + } + + ret = pinctrl_select_state(sdhst->pinctrl, state); + if (ret) { + dev_warn(mmc_dev(mmc), "failed to select pinctrl state: %d\n", ret); + return 0; + } + dev_dbg(mmc_dev(mmc), "switched to %s pinctrl state\n", + ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180 ? "UHS" : "default"); + + return 0; +} + static inline int spacemit_sdhci_get_clocks(struct device *dev, struct sdhci_pltfm_host *pltfm_host) { @@ -252,6 +296,30 @@ static inline int spacemit_sdhci_get_resets(struct device *dev) return 0; } +static inline void spacemit_sdhci_get_pins(struct device *dev, + struct sdhci_pltfm_host *pltfm_host) +{ + struct spacemit_sdhci_host *sdhst = sdhci_pltfm_priv(pltfm_host); + + sdhst->pinctrl = devm_pinctrl_get(dev); + if (IS_ERR(sdhst->pinctrl)) { + sdhst->pinctrl = NULL; + dev_dbg(dev, "pinctrl not available, voltage switching will work without it\n"); + return; + } + + sdhst->pinctrl_default = pinctrl_lookup_state(sdhst->pinctrl, "default"); + if (IS_ERR(sdhst->pinctrl_default)) + sdhst->pinctrl_default = NULL; + + sdhst->pinctrl_uhs = pinctrl_lookup_state(sdhst->pinctrl, "uhs"); + if (IS_ERR(sdhst->pinctrl_uhs)) + sdhst->pinctrl_uhs = NULL; + + dev_dbg(dev, "pinctrl setup: default=%p, uhs=%p\n", + sdhst->pinctrl_default, sdhst->pinctrl_uhs); +} + static const struct sdhci_ops spacemit_sdhci_ops = { .get_max_clock = spacemit_sdhci_clk_get_max_clock, .reset = spacemit_sdhci_reset, @@ -324,6 +392,10 @@ static int spacemit_sdhci_probe(struct platform_device *pdev) host->mmc->caps |= MMC_CAP_NEED_RSP_BUSY; + spacemit_sdhci_get_pins(dev, pltfm_host); + + host->mmc_host_ops.start_signal_voltage_switch = spacemit_sdhci_start_signal_voltage_switch; + ret = spacemit_sdhci_get_clocks(dev, pltfm_host); if (ret) goto err_pltfm; -- 2.47.3