From: khilman@ti.com (Kevin Hilman) Date: Tue, 08 Feb 2011 10:31:41 -0800 Subject: [PATCH] i2c: OMAP: fix static suspend vs. runtime suspend In-Reply-To: <20110205160843.GD15795@trinity.fluff.org> (Ben Dooks's message of "Sat, 5 Feb 2011 16:08:43 +0000") References: <1296173921-4832-1-git-send-email-khilman@ti.com> <20110205160843.GD15795@trinity.fluff.org> Message-ID: <87d3n2nzsi.fsf@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Ben Dooks writes: > On Thu, Jan 27, 2011 at 04:18:41PM -0800, Kevin Hilman wrote: >> When runtime PM is enabled, each OMAP i2c device is suspended after >> each i2c xfer. However, there are two cases when the static suspend >> methods must be used to ensure the devices are suspended: >> >> 1) runtime PM is disabled, either at compile time or dynamically >> via /sys/devices/.../power/control. >> 2) an i2c client driver uses i2c during it's suspend callback, thus >> leaving the i2c driver active (NOTE: runtime suspend transitions are >> disabled during system suspend, so i2c activity during system >> suspend will runtime resume the device, but not runtime (re)suspend it.) >> >> Since the actual work to suspend the device is handled by the >> subsytem, call the bus methods to take care of it. >> >> NOTE: This takes care of a known suspend problem on OMAP3 where the >> TWL RTC driver does i2c xfers during its suspend path leaving the i2c >> driver in an active state (since runtime suspend transistions are >> disabled.) >> >> Signed-off-by: Kevin Hilman >> --- >> Ben, this is a regression in 2.6.38 so hopefully this can be queued >> in the 2.6.38-rc cycle. Thanks. > > Ok, after all the discussions should I keep it in my -rc queue? > Yes, please. Kevin