mmc: davinci: Add support for set_power callback

Some devices connected to the MMC bus are power controlled by external
means. For instance, an SDIO device may be powered down/up by an
external gpio line.

In order to avoid toggling power from within the MMC host driver, add a
set_power callback function, which will be called by set_ios upon
powering down/up.

Signed-off-by: Ido Yariv <ido@wizery.com>
CC: Chris Ball <cjb@laptop.org>
Acked-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

diff --git a/arch/arm/mach-davinci/include/mach/mmc.h b/arch/arm/mach-davinci/include/mach/mmc.h
index d4f1e96..5ba6b22 100644 (file)
--- a/arch/arm/mach-davinci/include/mach/mmc.h
+++ b/arch/arm/mach-davinci/include/mach/mmc.h
@@ -12,6 +12,9 @@ struct davinci_mmc_config {
        /* get_cd()/get_wp() may sleep */
        int     (*get_cd)(int module);
        int     (*get_ro)(int module);
+
+       void    (*set_power)(int module, bool on);
+
        /* wires == 0 is equivalent to wires == 4 (4-bit parallel) */
        u8      wires;
 

diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 0076c74..64a8325 100644 (file)
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -807,12 +807,25 @@ static void calculate_clk_divider(struct mmc_host *mmc, struct mmc_ios *ios)
 static void mmc_davinci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 {
        struct mmc_davinci_host *host = mmc_priv(mmc);
+       struct platform_device *pdev = to_platform_device(mmc->parent);
+       struct davinci_mmc_config *config = pdev->dev.platform_data;
 
        dev_dbg(mmc_dev(host->mmc),
                "clock %dHz busmode %d powermode %d Vdd %04x\n",
                ios->clock, ios->bus_mode, ios->power_mode,
                ios->vdd);
 
+       switch (ios->power_mode) {
+       case MMC_POWER_OFF:
+               if (config && config->set_power)
+                       config->set_power(pdev->id, false);
+               break;
+       case MMC_POWER_UP:
+               if (config && config->set_power)
+                       config->set_power(pdev->id, true);
+               break;
+       }
+
        switch (ios->bus_width) {
        case MMC_BUS_WIDTH_8:
                dev_dbg(mmc_dev(host->mmc), "Enabling 8 bit mode\n");