OMAP3: wait on IDLEST after enabling USBTLL fclk

We need to wait on the IDLEST bit after the clocks are enabled
before attempting to access any register.

Currently, the USBTLL i-clock ops uses the clkops_omap2_dflt_wait,
while the USBTLL f-clock ops uses clkops_omap2_dflt. If the
i-clock is enabled first, the clkops_omap2_dflt_wait is
short-circuited as the companion f-clock is not enabled.
This can cause a data abort if the IDLEST has not transitioned,
and we try to access a USBTLL register.

Since the USBTLL i-clock and f-clock could be enabled in any order,
this is a bug. Fix it by changing the clkops for the f-clock.

Signed-off-by: Anand Gadiyar <gadiyar@ti.com>
Acked-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>

diff --git a/arch/arm/mach-omap2/clock3xxx_data.c b/arch/arm/mach-omap2/clock3xxx_data.c
index 41b155a..c226798 100644 (file)
--- a/arch/arm/mach-omap2/clock3xxx_data.c
+++ b/arch/arm/mach-omap2/clock3xxx_data.c
@@ -1408,7 +1408,7 @@ static struct clk ts_fck = {
 
 static struct clk usbtll_fck = {
        .name           = "usbtll_fck",
-       .ops            = &clkops_omap2_dflt,
+       .ops            = &clkops_omap2_dflt_wait,
        .parent         = &dpll5_m2_ck,
        .enable_reg     = OMAP_CM_REGADDR(CORE_MOD, OMAP3430ES2_CM_FCLKEN3),
        .enable_bit     = OMAP3430ES2_EN_USBTLL_SHIFT,