mmc: core: Factor out common code in drive strength selection
Make a new function out of common code used for drive
strength selection.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 95009f9..9ad73f3 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1639,6 +1639,44 @@
mmc_host_clk_release(host);
}
+int mmc_select_drive_strength(struct mmc_card *card, unsigned int max_dtr,
+ int card_drv_type, int *drv_type)
+{
+ struct mmc_host *host = card->host;
+ int host_drv_type = SD_DRIVER_TYPE_B;
+ int drive_strength;
+
+ *drv_type = 0;
+
+ if (!host->ops->select_drive_strength)
+ return 0;
+
+ /* Use SD definition of driver strength for hosts */
+ if (host->caps & MMC_CAP_DRIVER_TYPE_A)
+ host_drv_type |= SD_DRIVER_TYPE_A;
+
+ if (host->caps & MMC_CAP_DRIVER_TYPE_C)
+ host_drv_type |= SD_DRIVER_TYPE_C;
+
+ if (host->caps & MMC_CAP_DRIVER_TYPE_D)
+ host_drv_type |= SD_DRIVER_TYPE_D;
+
+ /*
+ * The drive strength that the hardware can support
+ * depends on the board design. Pass the appropriate
+ * information and let the hardware specific code
+ * return what is possible given the options
+ */
+ mmc_host_clk_hold(host);
+ drive_strength = host->ops->select_drive_strength(card, max_dtr,
+ host_drv_type,
+ card_drv_type,
+ drv_type);
+ mmc_host_clk_release(host);
+
+ return drive_strength;
+}
+
/*
* Apply power to the MMC stack. This is a two-stage process.
* First, we enable power to the card without the clock running.