omap_hsmmc: keep track of power mode

This patch is preparation for adding context save and restore support.

Keep track of the current power mode so that the context restore function
can avoid restoring the context for a card if the power has been switched
off.  If the power is off, the card must be reinitialized anyway which
will re-establish the context.
Signed-off-by: NAdrian Hunter <adrian.hunter@nokia.com>
Acked-by: NMatt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/mmc/host/omap_hsmmc.c

@@ -143,6 +143,7 @@ struct mmc_omap_host {
 	unsigned int		dma_len;
 	unsigned int		dma_sg_idx;
 	unsigned char		bus_mode;
+	unsigned char		power_mode;
 	u32			*buffer;
 	u32			bytesleft;
 	int			suspended;
@@ -863,16 +864,25 @@ static void omap_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	unsigned long regval;
 	unsigned long timeout;
 	u32 con;
+	int do_send_init_stream = 0;
 
 	mmc_host_enable(host->mmc);
 
-	switch (ios->power_mode) {
-	case MMC_POWER_OFF:
-		mmc_slot(host).set_power(host->dev, host->slot_id, 0, 0);
-		break;
-	case MMC_POWER_UP:
-		mmc_slot(host).set_power(host->dev, host->slot_id, 1, ios->vdd);
-		break;
+	if (ios->power_mode != host->power_mode) {
+		switch (ios->power_mode) {
+		case MMC_POWER_OFF:
+			mmc_slot(host).set_power(host->dev, host->slot_id,
+						 0, 0);
+			break;
+		case MMC_POWER_UP:
+			mmc_slot(host).set_power(host->dev, host->slot_id,
+						 1, ios->vdd);
+			break;
+		case MMC_POWER_ON:
+			do_send_init_stream = 1;
+			break;
+		}
+		host->power_mode = ios->power_mode;
 	}
 
 	con = OMAP_HSMMC_READ(host->base, CON);
@@ -938,7 +948,7 @@ static void omap_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	OMAP_HSMMC_WRITE(host->base, SYSCTL,
 		OMAP_HSMMC_READ(host->base, SYSCTL) | CEN);
 
-	if (ios->power_mode == MMC_POWER_ON)
+	if (do_send_init_stream)
 		send_init_stream(host);
 
 	if (ios->bus_mode == MMC_BUSMODE_OPENDRAIN)
@@ -1116,6 +1126,7 @@ static int __init omap_mmc_probe(struct platform_device *pdev)
 	host->slot_id	= 0;
 	host->mapbase	= res->start;
 	host->base	= ioremap(host->mapbase, SZ_4K);
+	host->power_mode = -1;
 
 	platform_set_drvdata(pdev, host);
 	INIT_WORK(&host->mmc_carddetect_work, mmc_omap_detect);