mmc: core: Allow card drive strength to be different to host
Initialization of UHS-I modes for SD and SDIO cards
employs a callback to allow the host driver to
choose a drive strength value. Currently that
assumes the card drive strength and host driver
type must be the same value. Change to let the
callback make that decision and return both the
card drive strength and host driver type.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c
index 8f6864a..5edd7d8 100644
--- a/drivers/mmc/core/sd.c
+++ b/drivers/mmc/core/sd.c
@@ -388,18 +388,9 @@
{
int host_drv_type = SD_DRIVER_TYPE_B;
int card_drv_type = SD_DRIVER_TYPE_B;
- int drive_strength;
+ int drive_strength, drv_type;
int err;
- /*
- * If the host doesn't support any of the Driver Types A,C or D,
- * or there is no board specific handler then default Driver
- * Type B is used.
- */
- if (!(card->host->caps & (MMC_CAP_DRIVER_TYPE_A | MMC_CAP_DRIVER_TYPE_C
- | MMC_CAP_DRIVER_TYPE_D)))
- return 0;
-
if (!card->host->ops->select_drive_strength)
return 0;
@@ -430,20 +421,22 @@
mmc_host_clk_hold(card->host);
drive_strength = card->host->ops->select_drive_strength(
card->sw_caps.uhs_max_dtr,
- host_drv_type, card_drv_type);
+ host_drv_type, card_drv_type, &drv_type);
mmc_host_clk_release(card->host);
- err = mmc_sd_switch(card, 1, 2, drive_strength, status);
- if (err)
- return err;
-
- if ((status[15] & 0xF) != drive_strength) {
- pr_warn("%s: Problem setting drive strength!\n",
- mmc_hostname(card->host));
- return 0;
+ if (drive_strength) {
+ err = mmc_sd_switch(card, 1, 2, drive_strength, status);
+ if (err)
+ return err;
+ if ((status[15] & 0xF) != drive_strength) {
+ pr_warn("%s: Problem setting drive strength!\n",
+ mmc_hostname(card->host));
+ return 0;
+ }
}
- mmc_set_driver_type(card->host, drive_strength);
+ if (drv_type)
+ mmc_set_driver_type(card->host, drv_type);
return 0;
}