Hi, On Monday 23 March 2015 04:05 AM, NeilBrown wrote: > From: NeilBrown <neilb@xxxxxxx> > > A construct like: > > if (pm_runtime_suspended(twl->dev)) > pm_runtime_get_sync(twl->dev); > > is against the spirit of the runtime_pm interface as it > makes the internal refcounting useless. > > In this case it is also racy, particularly as 'put_autosuspend' > is use to drop a reference. > When that happens a timer is started and the device is > runtime-suspended after the timeout. > If the above code runs in this window, the device will not be > found to be suspended so no pm_runtime reference is taken. > When the timer expires the device will be suspended, which is > against the intention of the code. > > So be more direct is taking and dropping references. > If twl->linkstat is VBUS_VALID or ID_GROUND, then hold a > pm_runtime reference, otherwise don't. > Define "cable_present()" to test for this condition. minor comment below.. > > Tested-by: Tony Lindgren <tony@xxxxxxxxxxx> > Signed-off-by: NeilBrown <neilb@xxxxxxx> > --- > drivers/phy/phy-twl4030-usb.c | 29 ++++++++++++++++++++--------- > 1 file changed, 20 insertions(+), 9 deletions(-) > > diff --git a/drivers/phy/phy-twl4030-usb.c b/drivers/phy/phy-twl4030-usb.c > index 8e87f54671f3..1a244f34b748 100644 > --- a/drivers/phy/phy-twl4030-usb.c > +++ b/drivers/phy/phy-twl4030-usb.c > @@ -144,6 +144,16 @@ > #define PMBR1 0x0D > #define GPIO_USB_4PIN_ULPI_2430C (3 << 0) > > +/* > + * If VBUS is valid or ID is ground, then we know a > + * cable is present and we need to be runtime-enabled > + */ > +static inline bool cable_present(enum omap_musb_vbus_id_status stat) twl4030_cable_present? -Kishon -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
