mmc: mmci: add f_max to variant structure

Some of the controller have maximum supported frequency, This patch adds
support in variant data structure to specify such restrictions. This
gives more flexibility in calculating the f_max before passing it to
mmc-core.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
index 0a8cdac..b588810 100644
--- a/drivers/mmc/host/mmci.c
+++ b/drivers/mmc/host/mmci.c
@@ -67,6 +67,7 @@
  * @blksz_datactrl4: true if Block size is at b4..b16 position in datactrl
  *		     register
  * @pwrreg_powerup: power up value for MMCIPOWER register
+ * @f_max: maximum clk frequency supported by the controller.
  * @signal_direction: input/out direction of bus signals can be indicated
  * @pwrreg_clkgate: MMCIPOWER register must be used to gate the clock
  * @busy_detect: true if busy detection on dat0 is supported
@@ -87,6 +88,7 @@
 	bool			blksz_datactrl16;
 	bool			blksz_datactrl4;
 	u32			pwrreg_powerup;
+	u32			f_max;
 	bool			signal_direction;
 	bool			pwrreg_clkgate;
 	bool			busy_detect;
@@ -98,6 +100,7 @@
 	.fifohalfsize		= 8 * 4,
 	.datalength_bits	= 16,
 	.pwrreg_powerup		= MCI_PWR_UP,
+	.f_max			= 100000000,
 };
 
 static struct variant_data variant_arm_extended_fifo = {
@@ -105,6 +108,7 @@
 	.fifohalfsize		= 64 * 4,
 	.datalength_bits	= 16,
 	.pwrreg_powerup		= MCI_PWR_UP,
+	.f_max			= 100000000,
 };
 
 static struct variant_data variant_arm_extended_fifo_hwfc = {
@@ -113,6 +117,7 @@
 	.clkreg_enable		= MCI_ARM_HWFCEN,
 	.datalength_bits	= 16,
 	.pwrreg_powerup		= MCI_PWR_UP,
+	.f_max			= 100000000,
 };
 
 static struct variant_data variant_u300 = {
@@ -123,6 +128,7 @@
 	.datalength_bits	= 16,
 	.sdio			= true,
 	.pwrreg_powerup		= MCI_PWR_ON,
+	.f_max			= 100000000,
 	.signal_direction	= true,
 	.pwrreg_clkgate		= true,
 	.pwrreg_nopower		= true,
@@ -136,6 +142,7 @@
 	.sdio			= true,
 	.st_clkdiv		= true,
 	.pwrreg_powerup		= MCI_PWR_ON,
+	.f_max			= 100000000,
 	.signal_direction	= true,
 	.pwrreg_clkgate		= true,
 	.pwrreg_nopower		= true,
@@ -152,6 +159,7 @@
 	.sdio			= true,
 	.st_clkdiv		= true,
 	.pwrreg_powerup		= MCI_PWR_ON,
+	.f_max			= 100000000,
 	.signal_direction	= true,
 	.pwrreg_clkgate		= true,
 	.busy_detect		= true,
@@ -171,6 +179,7 @@
 	.st_clkdiv		= true,
 	.blksz_datactrl16	= true,
 	.pwrreg_powerup		= MCI_PWR_ON,
+	.f_max			= 100000000,
 	.signal_direction	= true,
 	.pwrreg_clkgate		= true,
 	.busy_detect		= true,
@@ -1473,8 +1482,8 @@
 	 * so we try to adjust the clock down to this,
 	 * (if possible).
 	 */
-	if (host->mclk > 100000000) {
-		ret = clk_set_rate(host->clk, 100000000);
+	if (host->mclk > variant->f_max) {
+		ret = clk_set_rate(host->clk, variant->f_max);
 		if (ret < 0)
 			goto clk_disable;
 		host->mclk = clk_get_rate(host->clk);