Add support for eMMC hardware reset for BYT eMMC.
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
---
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 611331a..e082fac 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;
--
1.7.11.7
--
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