ARM: davinci: clk framework support for enable/disable functionality

DaVinci clock implementation does not support clock enable/disable
functionality on non-PSC clock nodes.

On DA850 SoC, EHRPWM module requires support for enable/disable
of TBCLK controlled using a system module register.

This patch adds a method for enabling/disabling non-PSC clocks
into DaVinci clock implementation.
Signed-off-by: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>

arch/arm/mach-davinci/clock.c

@@ -35,19 +35,26 @@ static void __clk_enable(struct clk *clk)
 {
 	if (clk->parent)
 		__clk_enable(clk->parent);
-	if (clk->usecount++ == 0 && (clk->flags & CLK_PSC))
+	if (clk->usecount++ == 0) {
+		if (clk->flags & CLK_PSC)
 			davinci_psc_config(clk->domain, clk->gpsc, clk->lpsc,
 					   true, clk->flags);
+		else if (clk->clk_enable)
+			clk->clk_enable(clk);
+	}
 }
 
 static void __clk_disable(struct clk *clk)
 {
 	if (WARN_ON(clk->usecount == 0))
 		return;
-	if (--clk->usecount == 0 && !(clk->flags & CLK_PLL) &&
-	    (clk->flags & CLK_PSC))
+	if (--clk->usecount == 0) {
+		if (!(clk->flags & CLK_PLL) && (clk->flags & CLK_PSC))
 			davinci_psc_config(clk->domain, clk->gpsc, clk->lpsc,
 					   false, clk->flags);
+		else if (clk->clk_disable)
+			clk->clk_disable(clk);
+	}
 	if (clk->parent)
 		__clk_disable(clk->parent);
 }

arch/arm/mach-davinci/clock.h

@@ -104,6 +104,8 @@ struct clk {
 	int (*set_rate) (struct clk *clk, unsigned long rate);
 	int (*round_rate) (struct clk *clk, unsigned long rate);
 	int (*reset) (struct clk *clk, bool reset);
+	void (*clk_enable) (struct clk *clk);
+	void (*clk_disable) (struct clk *clk);
 };
 
 /* Clock flags: SoC-specific flags start at BIT(16) */