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mmc: propagate error codes back from bus drivers' suspend/resume methods

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Especially for SDIO drivers which may have special conditions/errors to
report, it is a good thing to relay the returned error code back to upper
layers.

This also allows for the rationalization of the resume path where code to
"remove" a no-longer-existing or replaced card was duplicated into the
MMC, SD and SDIO bus drivers.

In the SDIO case, if a function suspend method returns an error, then all
previously suspended functions are resumed and the error returned.  An
exception is made for -ENOSYS which the core interprets as "we don't
support suspend so just kick the card out for suspend and return success".

When resuming SDIO cards, the core code only validates the manufacturer
and product IDs to make sure the same kind of card is still present before
invoking functions resume methods.  It's the function driver's
responsibility to perform further tests to confirm that the actual same
card is present (same MAC address, etc.) and return an error otherwise.

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Nicolas Pitre
2009-09-22 16:45:29 -07:00
committed by Linus Torvalds
parent 17d33e14f7
commit 95cdfb72b9
5 changed files with 85 additions and 70 deletions
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35
drivers/mmc/core/core.c
View File

@@ -1236,6 +1236,8 @@ EXPORT_SYMBOL(mmc_card_can_sleep);
*/
int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
{
int err = 0;
if (host->caps & MMC_CAP_DISABLE)
cancel_delayed_work(&host->disable);
cancel_delayed_work(&host->detect);
@@ -1244,21 +1246,26 @@ int mmc_suspend_host(struct mmc_host *host, pm_message_t state)
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead) {
if (host->bus_ops->suspend)
host->bus_ops->suspend(host);
if (!host->bus_ops->resume) {
err = host->bus_ops->suspend(host);
if (err == -ENOSYS || !host->bus_ops->resume) {
/*
* We simply "remove" the card in this case.
* It will be redetected on resume.
*/
if (host->bus_ops->remove)
host->bus_ops->remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
err = 0;
}
}
mmc_bus_put(host);
mmc_power_off(host);
if (!err)
mmc_power_off(host);
return 0;
return err;
}
EXPORT_SYMBOL(mmc_suspend_host);
@@ -1269,12 +1276,26 @@ EXPORT_SYMBOL(mmc_suspend_host);
*/
int mmc_resume_host(struct mmc_host *host)
{
int err = 0;
mmc_bus_get(host);
if (host->bus_ops && !host->bus_dead) {
mmc_power_up(host);
mmc_select_voltage(host, host->ocr);
BUG_ON(!host->bus_ops->resume);
host->bus_ops->resume(host);
err = host->bus_ops->resume(host);
if (err) {
printk(KERN_WARNING "%s: error %d during resume "
"(card was removed?)\n",
mmc_hostname(host), err);
if (host->bus_ops->remove)
host->bus_ops->remove(host);
mmc_claim_host(host);
mmc_detach_bus(host);
mmc_release_host(host);
/* no need to bother upper layers */
err = 0;
}
}
mmc_bus_put(host);
@@ -1284,7 +1305,7 @@ int mmc_resume_host(struct mmc_host *host)
*/
mmc_detect_change(host, 1);
return 0;
return err;
}
EXPORT_SYMBOL(mmc_resume_host);