From 28f52482b41edc88cdf575aa6ed414c6e116ce10 Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Tue, 17 Jun 2008 18:17:15 +0400 Subject: mmc: add support for card-detection polling Some hosts (and boards that use mmc_spi) do not use interrupts on the CD line, so they can't trigger mmc_detect_change. We want to poll the card and see if there was a change. 1 second poll interval seems resonable. This patch also implements .get_cd() host operation, that could be used by the hosts that are able to report card-detect status without need to talk MMC. Signed-off-by: Anton Vorontsov Signed-off-by: Pierre Ossman --- include/linux/mmc/host.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include') diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h index 7ab962f..6188e19 100644 --- a/include/linux/mmc/host.h +++ b/include/linux/mmc/host.h @@ -51,8 +51,18 @@ struct mmc_ios { struct mmc_host_ops { void (*request)(struct mmc_host *host, struct mmc_request *req); + /* + * Avoid calling these three functions too often or in a "fast path", + * since underlaying controller might implement them in an expensive + * and/or slow way. + * + * Also note that these functions might sleep, so don't call them + * in the atomic contexts! + */ void (*set_ios)(struct mmc_host *host, struct mmc_ios *ios); int (*get_ro)(struct mmc_host *host); + int (*get_cd)(struct mmc_host *host); + void (*enable_sdio_irq)(struct mmc_host *host, int enable); }; @@ -94,6 +104,7 @@ struct mmc_host { #define MMC_CAP_SD_HIGHSPEED (1 << 3) /* Can do SD high-speed timing */ #define MMC_CAP_SDIO_IRQ (1 << 4) /* Can signal pending SDIO IRQs */ #define MMC_CAP_SPI (1 << 5) /* Talks only SPI protocols */ +#define MMC_CAP_NEEDS_POLL (1 << 6) /* Needs polling for card-detection */ /* host specific block data */ unsigned int max_seg_size; /* see blk_queue_max_segment_size */ -- cgit v1.1