mmc: core: fix improper clock frequency being passed to set_ios
This bug was introduced in the 'MMC-4.5 Power OFF Notify Rework' fix.
Prior to the aforementioned patch, during resume mmc_init_card was being
invoked. The aforesaid patch invokes mmc_card_awake, prior to which
mmc_power_up has already set the clock frequency to 400Khz. Since the card
init is not done again, this frequency stays as is and results in data
time-out errors.
Two new functions
* mmc_save_ios
* mmc_restore_ios
were added.
The mmc_save_ios is invoked during mmc_suspend process and it saves the
current ios values, while mmc_restore_ios is invoked during mmc_resume process
and restores the previous ios values before sending the awake command. This
ensures that the clock, timing, bus-width etc are set properly before any
request is sent to the driver.
Signed-off-by: Asutosh Das <asutoshd@codeaurora.org>
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 4d948ea..71484da 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -355,6 +355,7 @@
bool perf_enable;
#endif
+ struct mmc_ios saved_ios;
unsigned long private[0] ____cacheline_aligned;
};