[PATCH 1/2] mmc: core: Add new power_mode MMC_POWER_UNDEFINED

[Roger Tseng]

Define new macro MMC_POWER_UNDEFINED for power_mode in struct mmc_ios.
It will also be set as the initial value of host->ios.power_mode in
mmc_start_host().

For hosts with MMC_CAP2_NO_PRESCAN_POWERUP, this makes the later
mmc_power_off() do real power-off things instead of NOP, and further
prevents state messed up in cards that was already initialized(eg. by
BIOS of UEFI driver).

Signed-off-by: Roger Tseng <rogerable at realtek.com>
---
 drivers/mmc/core/core.c  |    1 +
 include/linux/mmc/host.h |    1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index d03a080fb9cd..7dad1a1adf18 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -2489,6 +2489,7 @@ void mmc_start_host(struct mmc_host *host)
 {
 	host->f_init = max(freqs[0], host->f_min);
 	host->rescan_disable = 0;
+	host->ios.power_mode = MMC_POWER_UNDEFINED;
 	if (host->caps2 & MMC_CAP2_NO_PRESCAN_POWERUP)
 		mmc_power_off(host);
 	else
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 7960424d0bc0..b3bfa609816a 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -42,6 +42,7 @@ struct mmc_ios {
 #define MMC_POWER_OFF		0
 #define MMC_POWER_UP		1
 #define MMC_POWER_ON		2
+#define MMC_POWER_UNDEFINED	3
 
 	unsigned char	bus_width;		/* data bus width */
 
-- 
1.7.10.4