ARM: davinci: convert platform code to use clk_prepare/clk_unprepare

As a first step towards migrating davinci platforms to use common clock
framework, replace all instances of clk_enable() with clk_prepare_enable()
and clk_disable() with clk_disable_unprepare(). Until the platform is
switched to use the CONFIG_HAVE_CLK_PREPARE Kconfig variable, this just
adds a might_sleep() call and would work without any issues.

This will make it easy later to switch to common clk based implementation
of clk driver from DaVinci specific driver.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Reviewed-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
diff --git a/arch/arm/mach-davinci/board-dm365-evm.c b/arch/arm/mach-davinci/board-dm365-evm.c
index 1b4a8ad..5d49c75 100644
--- a/arch/arm/mach-davinci/board-dm365-evm.c
+++ b/arch/arm/mach-davinci/board-dm365-evm.c
@@ -478,7 +478,7 @@
 	aemif_clk = clk_get(NULL, "aemif");
 	if (IS_ERR(aemif_clk))
 		return;
-	clk_enable(aemif_clk);
+	clk_prepare_enable(aemif_clk);
 
 	if (request_mem_region(DM365_ASYNC_EMIF_DATA_CE1_BASE, SECTION_SIZE,
 			"cpld") == NULL)
@@ -489,7 +489,7 @@
 				SECTION_SIZE);
 fail:
 		pr_err("ERROR: can't map CPLD\n");
-		clk_disable(aemif_clk);
+		clk_disable_unprepare(aemif_clk);
 		return;
 	}