UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

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 <ext-jorg.2.schummer@nokia.com>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>
This commit is contained in:
Jorg Schummer 2009-03-31 17:51:21 +03:00 committed by Pierre Ossman
parent f3ad116588
commit 94d89efb2c
1 changed files with 64 additions and 53 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

117
drivers/mmc/core/core.c
View File

@ -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.
*/
mmc_bus_put(host);
if (host->ops->get_cd && host->ops->get_cd(host) == 0)
goto out;
mmc_claim_host(host);
mmc_power_up(host);
mmc_go_idle(host);
mmc_send_if_cond(host, host->ocr_avail);
/*
* 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;
}
/*
* ...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;
}
/*
* ...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);
} else {
if (host->bus_ops->detect && !host->bus_dead)
host->bus_ops->detect(host);
/* 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;
}
/* detect a newly inserted card */
/*
* Only we can add a new handler, so it's safe to
* release the lock here.
*/
mmc_bus_put(host);
if (host->ops->get_cd && host->ops->get_cd(host) == 0)
goto out;
mmc_claim_host(host);
mmc_power_up(host);
mmc_go_idle(host);
mmc_send_if_cond(host, host->ocr_avail);
/*
* 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;
}
/*
* ...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;
}
/*
* ...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);