On 06/29/2012 11:27 PM, Shilimkar, Santosh wrote: > + Paul, Rajendra, > > On Sat, Jun 30, 2012 at 2:34 AM, Jon Hunter <jon-hunter@xxxxxx> wrote: >> Note: Re-sending with updated kernel doc. >> >> The wake-up power domain is an alway-on power domain and so this power domain >> does not have a power state status (PM_PWSTST_xxx) register that indicates the >> current state. However, during the registering of the wake-up power domain the >> state of the domain is queried by calling pwrdm_read_pwrst(). This actually >> tries to read a register that does not exist and returns a value of 0 that >> indicates that the current state is OFF. The OFF state count of the wake-up >> power domain is then set to 1 and the current state to OFF. Both of which are >> incorrect. >> >> To fix this, if a power domain only supports the ON state, do not attempt to >> read the power state status register and simply return ON as the current power >> state. >> >> This is based upon Tony's current linux-omap master branch. >> >> Testing: >> - Boot tested on OMAP4460 panda. >> - Boot tested on OMAP3430 beagle and validated CORE RET still working (using >> Paul's 32k timer patch [1]). >> >> [1] http://marc.info/?l=linux-omap&m=134000053229888&w=2 >> >> Signed-off-by: Jon Hunter <jon-hunter@xxxxxx> >> --- >> arch/arm/mach-omap2/powerdomain.c | 6 +++++- >> 1 file changed, 5 insertions(+), 1 deletion(-) >> >> diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c >> index eefe179..69b36e1 100644 >> --- a/arch/arm/mach-omap2/powerdomain.c >> +++ b/arch/arm/mach-omap2/powerdomain.c >> @@ -526,7 +526,8 @@ int pwrdm_read_next_pwrst(struct powerdomain *pwrdm) >> * >> * Return the powerdomain @pwrdm's current power state. Returns -EINVAL >> * if the powerdomain pointer is null or returns the current power state >> - * upon success. >> + * upon success. Note that if the power domain only supports the ON state >> + * then just return ON as the current state. >> */ >> int pwrdm_read_pwrst(struct powerdomain *pwrdm) >> { >> @@ -535,6 +536,9 @@ int pwrdm_read_pwrst(struct powerdomain *pwrdm) >> if (!pwrdm) >> return -EINVAL; >> >> + if (pwrdm->pwrsts == PWRSTS_ON) >> + return PWRDM_POWER_ON; >> + > The patch as such is correct but just wondering whether we should > have some flag rather than above check. I was wondering that too. I opted not to add a flag because there is only one such power domain that needs it. However, I can add a flag if it is preferred. Cheers Jon -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
