mmc: sdhci: Introduce sdhci_calc_clk()

In order to remove the SDHCI_QUIRK2_NEED_DELAY_AFTER_INT_CLK_RST and to
reduce code duplication, put the code relative to the SD clock
configuration in a function which can be used by hosts for the
implementation of the ->set_clock() callback.

Signed-off-by: Ludovic Desroches <ludovic.desroches@atmel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci.c

@@ -1085,23 +1085,14 @@ static u16 sdhci_get_preset_value(struct sdhci_host *host)
 	return preset;
 }
 
-void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
+u16 sdhci_calc_clk(struct sdhci_host *host, unsigned int clock,
+		   unsigned int *actual_clock)
 {
 	int div = 0; /* Initialized for compiler warning */
 	int real_div = div, clk_mul = 1;
 	u16 clk = 0;
-	unsigned long timeout;
 	bool switch_base_clk = false;
 
-	host->mmc->actual_clock = 0;
-
-	sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
-	if (host->quirks2 & SDHCI_QUIRK2_NEED_DELAY_AFTER_INT_CLK_RST)
-		mdelay(1);
-
-	if (clock == 0)
-		return;
-
 	if (host->version >= SDHCI_SPEC_300) {
 		if (host->preset_enabled) {
 			u16 pre_val;
@@ -1178,10 +1169,31 @@ void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
 
 clock_set:
 	if (real_div)
-		host->mmc->actual_clock = (host->max_clk * clk_mul) / real_div;
+		*actual_clock = (host->max_clk * clk_mul) / real_div;
 	clk |= (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT;
 	clk |= ((div & SDHCI_DIV_HI_MASK) >> SDHCI_DIV_MASK_LEN)
 		<< SDHCI_DIVIDER_HI_SHIFT;
+
+	return clk;
+}
+EXPORT_SYMBOL_GPL(sdhci_calc_clk);
+
+void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
+{
+	u16 clk;
+	unsigned long timeout;
+
+	host->mmc->actual_clock = 0;
+
+	sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
+	if (host->quirks2 & SDHCI_QUIRK2_NEED_DELAY_AFTER_INT_CLK_RST)
+		mdelay(1);
+
+	if (clock == 0)
+		return;
+
+	clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
+
 	clk |= SDHCI_CLOCK_INT_EN;
 	sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
 

drivers/mmc/host/sdhci.h

@@ -661,6 +661,8 @@ static inline bool sdhci_sdio_irq_enabled(struct sdhci_host *host)
 	return !!(host->flags & SDHCI_SDIO_IRQ_ENABLED);
 }
 
+u16 sdhci_calc_clk(struct sdhci_host *host, unsigned int clock,
+		   unsigned int *actual_clock);
 void sdhci_set_clock(struct sdhci_host *host, unsigned int clock);
 void sdhci_set_power(struct sdhci_host *host, unsigned char mode,
 		     unsigned short vdd);