[PATCH] mmc: sdhci-sirf: fix 8bit width enable by overwriting set_bus_width
From: Barry Song <hidden>
Date: 2014-08-19 07:07:47
Also in:
linux-mmc
Subsystem:
multimedia card (mmc), secure digital (sd) and sdio subsystem, secure digital host controller interface (sdhci) driver, the rest · Maintainers:
Ulf Hansson, Adrian Hunter, Linus Torvalds
From: Minda Chen <redacted> 8bit-width enable bit of CSR MMC hosts is 3, while stardard hosts use bit 5. this patch fixes the functionality of 8bit transfer in CSR mmc controllers and improve performance for mmc0 a lot. Signed-off-by: Minda Chen <redacted> Signed-off-by: Barry Song <redacted> --- drivers/mmc/host/sdhci-sirf.c | 27 ++++++++++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci-sirf.c b/drivers/mmc/host/sdhci-sirf.c
index 1700453..376f45f 100644
--- a/drivers/mmc/host/sdhci-sirf.c
+++ b/drivers/mmc/host/sdhci-sirf.c@@ -15,6 +15,8 @@ #include <linux/mmc/slot-gpio.h> #include "sdhci-pltfm.h" +#define SDHCI_SIRF_8BITBUS BIT(3) + struct sdhci_sirf_priv { struct clk *clk; int gpio_cd;
@@ -27,10 +29,33 @@ static unsigned int sdhci_sirf_get_max_clk(struct sdhci_host *host) return clk_get_rate(priv->clk); } +static void sdhci_sirf_set_bus_width(struct sdhci_host *host, int width) +{ + u8 ctrl; + + ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL); + if (width == MMC_BUS_WIDTH_8) { + ctrl &= ~SDHCI_CTRL_4BITBUS; + /* + * 8bit-width enable bit of CSR MMC hosts is 3, + * while stardard hosts use bit 5 + */ + ctrl |= SDHCI_SIRF_8BITBUS; + } else { + if (host->version >= SDHCI_SPEC_300) + ctrl &= ~SDHCI_SIRF_8BITBUS; + if (width == MMC_BUS_WIDTH_4) + ctrl |= SDHCI_CTRL_4BITBUS; + else + ctrl &= ~SDHCI_CTRL_4BITBUS; + } + sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL); +} + static struct sdhci_ops sdhci_sirf_ops = { .set_clock = sdhci_set_clock, .get_max_clock = sdhci_sirf_get_max_clk, - .set_bus_width = sdhci_set_bus_width, + .set_bus_width = sdhci_sirf_set_bus_width, .reset = sdhci_reset, .set_uhs_signaling = sdhci_set_uhs_signaling, };
--
2.0.4
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