Commit 8d20b2ea authored by Kishon Vijay Abraham I's avatar Kishon Vijay Abraham I Committed by Ulf Hansson
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mmc: sdhci_omap: Add support to set IODELAY values



The data manual of J6/J6 Eco recommends to set different IODELAY values
depending on the mode in which the MMC/SD is enumerated in order to
ensure IO timings are met.

Add support to set the IODELAY values depending on the various MMC
modes using the pinctrl APIs.

Signed-off-by: default avatarKishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent 7d33c358
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+148 −0
Original line number Diff line number Diff line
@@ -25,6 +25,7 @@
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/pinctrl/consumer.h>

#include "sdhci-pltfm.h"

@@ -90,8 +91,12 @@

#define MAX_PHASE_DELAY		0x7C

/* sdhci-omap controller flags */
#define SDHCI_OMAP_REQUIRE_IODELAY	BIT(0)

struct sdhci_omap_data {
	u32 offset;
	u8 flags;
};

struct sdhci_omap_host {
@@ -102,8 +107,16 @@ struct sdhci_omap_host {
	struct sdhci_host	*host;
	u8			bus_mode;
	u8			power_mode;
	u8			timing;
	u8			flags;

	struct pinctrl		*pinctrl;
	struct pinctrl_state	**pinctrl_state;
};

static void sdhci_omap_start_clock(struct sdhci_omap_host *omap_host);
static void sdhci_omap_stop_clock(struct sdhci_omap_host *omap_host);

static inline u32 sdhci_omap_readl(struct sdhci_omap_host *host,
				   unsigned int offset)
{
@@ -436,6 +449,31 @@ static int sdhci_omap_start_signal_voltage_switch(struct mmc_host *mmc,
	return 0;
}

static void sdhci_omap_set_timing(struct sdhci_omap_host *omap_host, u8 timing)
{
	int ret;
	struct pinctrl_state *pinctrl_state;
	struct device *dev = omap_host->dev;

	if (!(omap_host->flags & SDHCI_OMAP_REQUIRE_IODELAY))
		return;

	if (omap_host->timing == timing)
		return;

	sdhci_omap_stop_clock(omap_host);

	pinctrl_state = omap_host->pinctrl_state[timing];
	ret = pinctrl_select_state(omap_host->pinctrl, pinctrl_state);
	if (ret) {
		dev_err(dev, "failed to select pinctrl state\n");
		return;
	}

	sdhci_omap_start_clock(omap_host);
	omap_host->timing = timing;
}

static void sdhci_omap_set_power_mode(struct sdhci_omap_host *omap_host,
				      u8 power_mode)
{
@@ -472,6 +510,7 @@ static void sdhci_omap_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
	omap_host = sdhci_pltfm_priv(pltfm_host);

	sdhci_omap_set_bus_mode(omap_host, ios->bus_mode);
	sdhci_omap_set_timing(omap_host, ios->timing);
	sdhci_set_ios(mmc, ios);
	sdhci_omap_set_power_mode(omap_host, ios->power_mode);
}
@@ -680,6 +719,7 @@ static const struct sdhci_pltfm_data sdhci_omap_pdata = {

static const struct sdhci_omap_data dra7_data = {
	.offset = 0x200,
	.flags	= SDHCI_OMAP_REQUIRE_IODELAY,
};

static const struct of_device_id omap_sdhci_match[] = {
@@ -688,6 +728,108 @@ static const struct of_device_id omap_sdhci_match[] = {
};
MODULE_DEVICE_TABLE(of, omap_sdhci_match);

static struct pinctrl_state
*sdhci_omap_iodelay_pinctrl_state(struct sdhci_omap_host *omap_host, char *mode,
				  u32 *caps, u32 capmask)
{
	struct device *dev = omap_host->dev;
	struct pinctrl_state *pinctrl_state = ERR_PTR(-ENODEV);

	if (!(*caps & capmask))
		goto ret;

	pinctrl_state = pinctrl_lookup_state(omap_host->pinctrl, mode);
	if (IS_ERR(pinctrl_state)) {
		dev_err(dev, "no pinctrl state for %s mode", mode);
		*caps &= ~capmask;
	}

ret:
	return pinctrl_state;
}

static int sdhci_omap_config_iodelay_pinctrl_state(struct sdhci_omap_host
						   *omap_host)
{
	struct device *dev = omap_host->dev;
	struct sdhci_host *host = omap_host->host;
	struct mmc_host *mmc = host->mmc;
	u32 *caps = &mmc->caps;
	u32 *caps2 = &mmc->caps2;
	struct pinctrl_state *state;
	struct pinctrl_state **pinctrl_state;

	if (!(omap_host->flags & SDHCI_OMAP_REQUIRE_IODELAY))
		return 0;

	pinctrl_state = devm_kzalloc(dev, sizeof(*pinctrl_state) *
				     (MMC_TIMING_MMC_HS200 + 1), GFP_KERNEL);
	if (!pinctrl_state)
		return -ENOMEM;

	omap_host->pinctrl = devm_pinctrl_get(omap_host->dev);
	if (IS_ERR(omap_host->pinctrl)) {
		dev_err(dev, "Cannot get pinctrl\n");
		return PTR_ERR(omap_host->pinctrl);
	}

	state = pinctrl_lookup_state(omap_host->pinctrl, "default");
	if (IS_ERR(state)) {
		dev_err(dev, "no pinctrl state for default mode\n");
		return PTR_ERR(state);
	}
	pinctrl_state[MMC_TIMING_LEGACY] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "sdr104", caps,
						 MMC_CAP_UHS_SDR104);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_UHS_SDR104] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "ddr50", caps,
						 MMC_CAP_UHS_DDR50);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_UHS_DDR50] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "sdr50", caps,
						 MMC_CAP_UHS_SDR50);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_UHS_SDR50] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "sdr25", caps,
						 MMC_CAP_UHS_SDR25);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_UHS_SDR25] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "sdr12", caps,
						 MMC_CAP_UHS_SDR12);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_UHS_SDR12] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "ddr_1_8v", caps,
						 MMC_CAP_1_8V_DDR);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_MMC_DDR52] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "hs", caps,
						 MMC_CAP_SD_HIGHSPEED);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_SD_HS] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "hs", caps,
						 MMC_CAP_MMC_HIGHSPEED);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_MMC_HS] = state;

	state = sdhci_omap_iodelay_pinctrl_state(omap_host, "hs200_1_8v", caps2,
						 MMC_CAP2_HS200_1_8V_SDR);
	if (!IS_ERR(state))
		pinctrl_state[MMC_TIMING_MMC_HS200] = state;

	omap_host->pinctrl_state = pinctrl_state;

	return 0;
}

static int sdhci_omap_probe(struct platform_device *pdev)
{
	int ret;
@@ -724,6 +866,8 @@ static int sdhci_omap_probe(struct platform_device *pdev)
	omap_host->base = host->ioaddr;
	omap_host->dev = dev;
	omap_host->power_mode = MMC_POWER_UNDEFINED;
	omap_host->timing = MMC_TIMING_LEGACY;
	omap_host->flags = data->flags;
	host->ioaddr += offset;

	mmc = host->mmc;
@@ -772,6 +916,10 @@ static int sdhci_omap_probe(struct platform_device *pdev)
		goto err_put_sync;
	}

	ret = sdhci_omap_config_iodelay_pinctrl_state(omap_host);
	if (ret)
		goto err_put_sync;

	host->mmc_host_ops.get_ro = mmc_gpio_get_ro;
	host->mmc_host_ops.start_signal_voltage_switch =
					sdhci_omap_start_signal_voltage_switch;