mx6: clock: Add thermal clock enable function

Add api to check and enable pll3 as required
for thermal sensor driver.

Signed-off-by: Ye.Li <B37916@freescale.com>
Signed-off-by: Nitin Garg <nitin.garg@freescale.com>
diff --git a/arch/arm/cpu/armv7/mx6/clock.c b/arch/arm/cpu/armv7/mx6/clock.c
index 6c9c78c..80b11aa 100644
--- a/arch/arm/cpu/armv7/mx6/clock.c
+++ b/arch/arm/cpu/armv7/mx6/clock.c
@@ -673,6 +673,36 @@
 }
 #endif
 
+static void enable_pll3(void)
+{
+	struct anatop_regs __iomem *anatop =
+		(struct anatop_regs __iomem *)ANATOP_BASE_ADDR;
+
+	/* make sure pll3 is enabled */
+	if ((readl(&anatop->usb1_pll_480_ctrl) &
+			BM_ANADIG_USB1_PLL_480_CTRL_LOCK) == 0) {
+		/* enable pll's power */
+		writel(BM_ANADIG_USB1_PLL_480_CTRL_POWER,
+		       &anatop->usb1_pll_480_ctrl_set);
+		writel(0x80, &anatop->ana_misc2_clr);
+		/* wait for pll lock */
+		while ((readl(&anatop->usb1_pll_480_ctrl) &
+			BM_ANADIG_USB1_PLL_480_CTRL_LOCK) == 0)
+			;
+		/* disable bypass */
+		writel(BM_ANADIG_USB1_PLL_480_CTRL_BYPASS,
+		       &anatop->usb1_pll_480_ctrl_clr);
+		/* enable pll output */
+		writel(BM_ANADIG_USB1_PLL_480_CTRL_ENABLE,
+		       &anatop->usb1_pll_480_ctrl_set);
+	}
+}
+
+void enable_thermal_clk(void)
+{
+	enable_pll3();
+}
+
 unsigned int mxc_get_clock(enum mxc_clock clk)
 {
 	switch (clk) {
diff --git a/arch/arm/include/asm/arch-mx6/clock.h b/arch/arm/include/asm/arch-mx6/clock.h
index 3c58a0a..8e51f9b 100644
--- a/arch/arm/include/asm/arch-mx6/clock.h
+++ b/arch/arm/include/asm/arch-mx6/clock.h
@@ -66,4 +66,5 @@
 void enable_ipu_clock(void);
 int enable_fec_anatop_clock(enum enet_freq freq);
 void enable_enet_clk(unsigned char enable);
+void enable_thermal_clk(void);
 #endif /* __ASM_ARCH_CLOCK_H */