From c9faff6cbb3d2b37b3aa356ce455848f91685b24 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Thu, 13 Jun 2013 11:50:26 +0300 Subject: [PATCH] mmc: sdhci-pci: add support for eMMC hardware reset for BYT eMMC. Add support for eMMC hardware reset for BYT eMMC. Signed-off-by: Adrian Hunter Signed-off-by: Chris Ball --- drivers/mmc/host/sdhci-pci.c | 32 ++++++++++++++++++++++++++++++-- 1 file changed, 30 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/sdhci-pci.c b/drivers/mmc/host/sdhci-pci.c index 611331a39fe5..e082fac6bc96 100644 --- a/drivers/mmc/host/sdhci-pci.c +++ b/drivers/mmc/host/sdhci-pci.c @@ -77,6 +77,8 @@ struct sdhci_pci_slot { int rst_n_gpio; int cd_gpio; int cd_irq; + + void (*hw_reset)(struct sdhci_host *host); }; struct sdhci_pci_chip { @@ -307,10 +309,27 @@ static const struct sdhci_pci_fixes sdhci_intel_pch_sdio = { .probe_slot = pch_hc_probe_slot, }; +static void sdhci_pci_int_hw_reset(struct sdhci_host *host) +{ + u8 reg; + + reg = sdhci_readb(host, SDHCI_POWER_CONTROL); + reg |= 0x10; + sdhci_writeb(host, reg, SDHCI_POWER_CONTROL); + /* For eMMC, minimum is 1us but give it 9us for good measure */ + udelay(9); + reg &= ~0x10; + sdhci_writeb(host, reg, SDHCI_POWER_CONTROL); + /* For eMMC, minimum is 200us but give it 300us for good measure */ + usleep_range(300, 1000); +} + static int byt_emmc_probe_slot(struct sdhci_pci_slot *slot) { - slot->host->mmc->caps |= MMC_CAP_8_BIT_DATA | MMC_CAP_NONREMOVABLE; + slot->host->mmc->caps |= MMC_CAP_8_BIT_DATA | MMC_CAP_NONREMOVABLE | + MMC_CAP_HW_RESET; slot->host->mmc->caps2 |= MMC_CAP2_HC_ERASE_SZ; + slot->hw_reset = sdhci_pci_int_hw_reset; return 0; } @@ -1016,7 +1035,7 @@ static int sdhci_pci_bus_width(struct sdhci_host *host, int width) return 0; } -static void sdhci_pci_hw_reset(struct sdhci_host *host) +static void sdhci_pci_gpio_hw_reset(struct sdhci_host *host) { struct sdhci_pci_slot *slot = sdhci_priv(host); int rst_n_gpio = slot->rst_n_gpio; @@ -1031,6 +1050,14 @@ static void sdhci_pci_hw_reset(struct sdhci_host *host) usleep_range(300, 1000); } +static void sdhci_pci_hw_reset(struct sdhci_host *host) +{ + struct sdhci_pci_slot *slot = sdhci_priv(host); + + if (slot->hw_reset) + slot->hw_reset(host); +} + static const struct sdhci_ops sdhci_pci_ops = { .enable_dma = sdhci_pci_enable_dma, .platform_bus_width = sdhci_pci_bus_width, @@ -1328,6 +1355,7 @@ static struct sdhci_pci_slot *sdhci_pci_probe_slot( if (!gpio_request(slot->rst_n_gpio, "eMMC_reset")) { gpio_direction_output(slot->rst_n_gpio, 1); slot->host->mmc->caps |= MMC_CAP_HW_RESET; + slot->hw_reset = sdhci_pci_gpio_hw_reset; } else { dev_warn(&pdev->dev, "failed to request rst_n_gpio\n"); slot->rst_n_gpio = -EINVAL; -- 2.30.2