ARM: OMAP: Add support for forcing osc_ck on

Some boards might use the oscillator clock for powering
external peripherals. Add support for making sure osc_ck
stays active even when trying to go to sleep.
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/clock.c

@@ -81,6 +81,14 @@ static void omap2_propagate_rate(struct clk * clk)
 	propagate_rate(clk);
 }
 
+static void omap2_set_osc_ck(int enable)
+{
+	if (enable)
+		PRCM_CLKSRC_CTRL &= ~(0x3 << 3);
+	else
+		PRCM_CLKSRC_CTRL |= 0x3 << 3;
+}
+
 /* Enable an APLL if off */
 static void omap2_clk_fixed_enable(struct clk *clk)
 {
@@ -121,6 +129,11 @@ static int _omap2_clk_enable(struct clk * clk)
 	if (clk->flags & ALWAYS_ENABLED)
 		return 0;
 
+	if (unlikely(clk == &osc_ck)) {
+		omap2_set_osc_ck(1);
+		return 0;
+	}
+
 	if (unlikely(clk->enable_reg == 0)) {
 		printk(KERN_ERR "clock.c: Enable for %s without enable code\n",
 		       clk->name);
@@ -158,6 +171,11 @@ static void _omap2_clk_disable(struct clk *clk)
 {
 	u32 regval32;
 
+	if (unlikely(clk == &osc_ck)) {
+		omap2_set_osc_ck(0);
+		return;
+	}
+
 	if (clk->enable_reg == 0)
 		return;
 

arch/arm/mach-omap2/clock.h

@@ -560,7 +560,7 @@ static struct clk osc_ck = {		/* (*12, *13, 19.2, *26, 38.4)MHz */
 	.name		= "osc_ck",
 	.rate		= 26000000,		/* fixed up in clock init */
 	.flags		= CLOCK_IN_OMAP242X | CLOCK_IN_OMAP243X |
-				RATE_FIXED | ALWAYS_ENABLED | RATE_PROPAGATES,
+				RATE_FIXED | RATE_PROPAGATES,
 };
 
 /* With out modem likely 12MHz, with modem likely 13MHz */