mmc: sdio: don't reinitialize nonremovable powered-resumed cards

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 (mmc: sdio: fully reconfigure oldcard on resume) 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@wizery.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

2 files changed, 19 insertions, 2 deletions

diff --git a/drivers/mmc/core/sdio.c b/drivers/mmc/core/sdio.c
index c18810ab6465..82f4b9008987 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 4a9d9d2589c7..3a85e73a38a9 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -320,5 +320,10 @@ 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