Upon system resume, SDIO core must reinitialize cards that were
powered off during suspend.
If the card had its power kept during suspend (and thus it
is 'powered-resumed'), SDIO core performs only a limited reinitializing,
mainly needed to make sure that the card wasn't removed/replaced.
If a __nonremovable__ card is powered-resumed, we can safely skip the
reinitializing phase.
Note: 9b966aa removed the bus width reconfiguration since
mmc_sdio_init_card already does it. It is brought back now in case
mmc_sdio_init_card is skipped.
Signed-off-by: Ohad Ben-Cohen <ohad@xxxxxxxxxx>
---
I have not switched all existing code to mmc_card_is_powered_resumed(),
I can do that as a subsequent clean up patch.
drivers/mmc/core/sdio.c | 16 ++++++++++++++--
include/linux/mmc/host.h | 5 +++++
2 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index efef5f9..b424fbe 100644
--- a/drivers/mmc/core/sdio.c
+++ b/drivers/mmc/core/sdio.c
@@ -627,15 +627,27 @@ static int mmc_sdio_suspend(struct mmc_host *host)
static int mmc_sdio_resume(struct mmc_host *host)
{
- int i, err;
+ int i, err = 0;
BUG_ON(!host);
BUG_ON(!host->card);
/* Basic card reinitialization. */
mmc_claim_host(host);
- err = mmc_sdio_init_card(host, host->ocr, host->card,
+
+ /* No need to reinitialize powered-resumed nonremovable cards */
+ if (mmc_card_is_removable(host) || !mmc_card_is_powered_resumed(host))
+ err = mmc_sdio_init_card(host, host->ocr, host->card,
(host->pm_flags & MMC_PM_KEEP_POWER));
+ else if (mmc_card_is_powered_resumed(host)) {
+ /* We may have switched to 1-bit mode during suspend */
+ err = sdio_enable_4bit_bus(host->card);
+ if (err > 0) {
+ mmc_set_bus_width(host, MMC_BUS_WIDTH_4);
+ err = 0;
+ }
+ }
+
if (!err && host->sdio_irqs)
mmc_signal_sdio_irq(host);
mmc_release_host(host);
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 381c77f..30b6fb9 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -317,5 +317,10 @@ static inline int mmc_card_is_removable(struct mmc_host *host)
return !(host->caps & MMC_CAP_NONREMOVABLE) && mmc_assume_removable;
}
+static inline int mmc_card_is_powered_resumed(struct mmc_host *host)
+{
+ return host->pm_flags & MMC_PM_KEEP_POWER;
+}
+
#endif
--
1.7.0.4
--
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