diff options
Diffstat (limited to 'drivers/mmc/core/core.c')
| -rw-r--r-- | drivers/mmc/core/core.c | 38 |
1 files changed, 38 insertions, 0 deletions
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 @@ void mmc_set_driver_type(struct mmc_host *host, unsigned int drv_type) 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. |