From 94d89efb2c347a82a08a61dbac8565b1087c3259 Mon Sep 17 00:00:00 2001 From: Jorg Schummer Date: Tue, 31 Mar 2009 17:51:21 +0300 Subject: mmc: mmc_rescan detects card change in one run With this patch, mmc_rescan can detect the removal of an mmc card and the insertion of (possibly another) card in the same run. This means that a card change can be detected without having to call mmc_detect_change multiple times. This change generalises the core such that it can be easily used by hosts which provide a mechanism to detect only the presence of a card reader cover, which has to be taken off in order to insert a card. Other hosts ("card detect" or "MMC_CAP_NEEDS_POLL") each receive an event when a card is removed and when a card is inserted, so it is sufficient for them if mmc_rescan handles only one event at a time. "Cover detect" hosts, however, only receive events about the cover status. This means that between 2 subsequent events, both a card removal and a card insertion can occur. In this case, the pre-patch version of mmc_rescan would only detect the removal of the previous card but not the insertion of the new card. Signed-off-by: Jorg Schummer Signed-off-by: Pierre Ossman --- drivers/mmc/core/core.c | 99 +++++++++++++++++++++++++++---------------------- 1 file changed, 55 insertions(+), 44 deletions(-) (limited to 'drivers/mmc') diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 264911732756..23fb2c39d9ed 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -855,61 +855,72 @@ void mmc_rescan(struct work_struct *work) mmc_bus_get(host); - if (host->bus_ops == NULL) { - /* - * Only we can add a new handler, so it's safe to - * release the lock here. - */ + /* if there is a card registered, check whether it is still present */ + if ((host->bus_ops != NULL) && host->bus_ops->detect && !host->bus_dead) + host->bus_ops->detect(host); + + mmc_bus_put(host); + + + mmc_bus_get(host); + + /* if there still is a card present, stop here */ + if (host->bus_ops != NULL) { mmc_bus_put(host); + goto out; + } - if (host->ops->get_cd && host->ops->get_cd(host) == 0) - goto out; + /* detect a newly inserted card */ - mmc_claim_host(host); + /* + * Only we can add a new handler, so it's safe to + * release the lock here. + */ + mmc_bus_put(host); - mmc_power_up(host); - mmc_go_idle(host); + if (host->ops->get_cd && host->ops->get_cd(host) == 0) + goto out; - mmc_send_if_cond(host, host->ocr_avail); + mmc_claim_host(host); - /* - * First we search for SDIO... - */ - err = mmc_send_io_op_cond(host, 0, &ocr); - if (!err) { - if (mmc_attach_sdio(host, ocr)) - mmc_power_off(host); - goto out; - } + mmc_power_up(host); + mmc_go_idle(host); - /* - * ...then normal SD... - */ - err = mmc_send_app_op_cond(host, 0, &ocr); - if (!err) { - if (mmc_attach_sd(host, ocr)) - mmc_power_off(host); - goto out; - } + mmc_send_if_cond(host, host->ocr_avail); - /* - * ...and finally MMC. - */ - err = mmc_send_op_cond(host, 0, &ocr); - if (!err) { - if (mmc_attach_mmc(host, ocr)) - mmc_power_off(host); - goto out; - } + /* + * First we search for SDIO... + */ + err = mmc_send_io_op_cond(host, 0, &ocr); + if (!err) { + if (mmc_attach_sdio(host, ocr)) + mmc_power_off(host); + goto out; + } - mmc_release_host(host); - mmc_power_off(host); - } else { - if (host->bus_ops->detect && !host->bus_dead) - host->bus_ops->detect(host); + /* + * ...then normal SD... + */ + err = mmc_send_app_op_cond(host, 0, &ocr); + if (!err) { + if (mmc_attach_sd(host, ocr)) + mmc_power_off(host); + goto out; + } - mmc_bus_put(host); + /* + * ...and finally MMC. + */ + err = mmc_send_op_cond(host, 0, &ocr); + if (!err) { + if (mmc_attach_mmc(host, ocr)) + mmc_power_off(host); + goto out; } + + mmc_release_host(host); + mmc_power_off(host); + out: if (host->caps & MMC_CAP_NEEDS_POLL) mmc_schedule_delayed_work(&host->detect, HZ); -- cgit v1.2.3