From b4f30a174e1fda8118eda038b5d8d5260db36ad5 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Fri, 6 Feb 2015 14:12:52 +0200 Subject: [PATCH] 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 Signed-off-by: Ulf Hansson --- drivers/mmc/core/sd.c | 33 ++++++++++++------------------ drivers/mmc/core/sdio.c | 43 +++++++++++++++++----------------------- include/linux/mmc/host.h | 3 ++- 3 files changed, 33 insertions(+), 46 deletions(-) diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index 8f6864a2a055..5edd7d8b033e 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -388,18 +388,9 @@ static int sd_select_driver_type(struct mmc_card *card, u8 *status) { 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 @@ static int sd_select_driver_type(struct mmc_card *card, u8 *status) 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; } diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c index 5c1423a3e7d7..9d87aeb7c752 100644 --- a/drivers/mmc/core/sdio.c +++ b/drivers/mmc/core/sdio.c @@ -404,21 +404,10 @@ static void sdio_select_driver_type(struct mmc_card *card) { int host_drv_type = SD_DRIVER_TYPE_B; int card_drv_type = SD_DRIVER_TYPE_B; - int drive_strength; + int drive_strength, drv_type; unsigned char card_strength; 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; - if (!card->host->ops->select_drive_strength) return; @@ -448,23 +437,27 @@ static void sdio_select_driver_type(struct mmc_card *card) */ 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); - /* if error just use default for drive strength B */ - err = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_DRIVE_STRENGTH, 0, - &card_strength); - if (err) - return; + if (drive_strength) { + /* if error just use default for drive strength B */ + err = mmc_io_rw_direct(card, 0, 0, SDIO_CCCR_DRIVE_STRENGTH, 0, + &card_strength); + if (err) + return; - card_strength &= ~(SDIO_DRIVE_DTSx_MASK<host, drive_strength); + if (drv_type) + mmc_set_driver_type(card->host, drv_type); } diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 433eccb50838..da33d18c66c8 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -132,7 +132,8 @@ struct mmc_host_ops { /* Prepare HS400 target operating frequency depending host driver */ int (*prepare_hs400_tuning)(struct mmc_host *host, struct mmc_ios *ios); - int (*select_drive_strength)(unsigned int max_dtr, int host_drv, int card_drv); + int (*select_drive_strength)(unsigned int max_dtr, int host_drv, + int card_drv, int *drv_type); void (*hw_reset)(struct mmc_host *host); void (*card_event)(struct mmc_host *host); -- 2.20.1