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>

1 files changed, 13 insertions, 0 deletions

diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index 0076c7448fe6..64a8325a4a8a 100644
--- 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");