From 0b03a931abcc7572489be07bee169a6d9a23832a Mon Sep 17 00:00:00 2001 From: Igor Grinberg Date: Mon, 3 Nov 2014 11:32:23 +0200 Subject: omap: hsmmc: assume cd gpio is active low Switch the default CD GPIO polarity to active low. The current hsmmc driver assumption that the CD GPIO is active high, but in the real hardware, usually the opposite holds. The usual SD card socket has a mechanical switch which is grounded as soon as a card is inserted. Of course there might be some board logic which inverts the signal, but as far as current users are concerned, there is no such logic. Current U-Boot users either not using the CD functionality, or have a different way (e.g. external to SoC GPIO controller) for checking the card presence. This patch also brings the polarity assumption in line with the Linux kernel and adds appropriate comments. This patch also might spare issues once the TWL GPIO driver will be converted to the DM. Signed-off-by: Igor Grinberg Cc: Pantelis Antoniou Cc: Dmitry Lifshitz Reviewed-by: Tom Rini --- drivers/mmc/omap_hsmmc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/mmc/omap_hsmmc.c b/drivers/mmc/omap_hsmmc.c index ef2cbf9e2f..ffb5284a00 100644 --- a/drivers/mmc/omap_hsmmc.c +++ b/drivers/mmc/omap_hsmmc.c @@ -611,7 +611,8 @@ static int omap_hsmmc_getcd(struct mmc *mmc) if (cd_gpio < 0) return 1; - return gpio_get_value(cd_gpio); + /* NOTE: assumes card detect signal is active-low */ + return !gpio_get_value(cd_gpio); } static int omap_hsmmc_getwp(struct mmc *mmc) @@ -624,6 +625,7 @@ static int omap_hsmmc_getwp(struct mmc *mmc) if (wp_gpio < 0) return 0; + /* NOTE: assumes write protect signal is active-high */ return gpio_get_value(wp_gpio); } #endif -- cgit v1.2.1