mxc pwm: add mx25 support

Signed-off-by: NSascha Hauer <s.hauer@pengutronix.de>

arch/arm/plat-mxc/pwm.c

@@ -32,6 +32,7 @@
 #define MX3_PWMPR                 0x10    /* PWM Period Register */
 #define MX3_PWMCR_PRESCALER(x)    (((x - 1) & 0xFFF) << 4)
 #define MX3_PWMCR_CLKSRC_IPG_HIGH (2 << 16)
+#define MX3_PWMCR_CLKSRC_IPG      (1 << 16)
 #define MX3_PWMCR_EN              (1 << 0)
 
 
@@ -55,9 +56,11 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
 	if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
 		return -EINVAL;
 
-	if (cpu_is_mx27() || cpu_is_mx3()) {
+	if (cpu_is_mx27() || cpu_is_mx3() || cpu_is_mx25()) {
 		unsigned long long c;
 		unsigned long period_cycles, duty_cycles, prescale;
+		u32 cr;
+
 		c = clk_get_rate(pwm->clk);
 		c = c * period_ns;
 		do_div(c, 1000000000);
@@ -72,9 +75,15 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
 
 		writel(duty_cycles, pwm->mmio_base + MX3_PWMSAR);
 		writel(period_cycles, pwm->mmio_base + MX3_PWMPR);
-		writel(MX3_PWMCR_PRESCALER(prescale) |
-			MX3_PWMCR_CLKSRC_IPG_HIGH | MX3_PWMCR_EN,
-			pwm->mmio_base + MX3_PWMCR);
+
+		cr = MX3_PWMCR_PRESCALER(prescale) | MX3_PWMCR_EN;
+
+		if (cpu_is_mx25())
+			cr |= MX3_PWMCR_CLKSRC_IPG;
+		else
+			cr |= MX3_PWMCR_CLKSRC_IPG_HIGH;
+
+		writel(cr, pwm->mmio_base + MX3_PWMCR);
 	} else if (cpu_is_mx1() || cpu_is_mx21()) {
 		/* The PWM subsystem allows for exact frequencies. However,
 		 * I cannot connect a scope on my device to the PWM line and