--- /dev/null
+From 35deff7eb212b661b32177b6043f674fde6314d7 Mon Sep 17 00:00:00 2001
+From: Jon Hunter <jonathanh@nvidia.com>
+Date: Fri, 20 Nov 2015 10:51:00 +0000
+Subject: mfd: as3722: Handle interrupts on suspend
+
+From: Jon Hunter <jonathanh@nvidia.com>
+
+commit 35deff7eb212b661b32177b6043f674fde6314d7 upstream.
+
+The as3722 device is registered as an irqchip and the as3722-rtc interrupt
+is one of it's interrupt sources. When using the as3722-rtc as a wake-up
+device from suspend, the following is seen:
+
+ PM: Syncing filesystems ... done.
+ Freezing user space processes ... (elapsed 0.001 seconds) done.
+ Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
+ Suspending console(s) (use no_console_suspend to debug)
+ PM: suspend of devices complete after 161.119 msecs
+ PM: late suspend of devices complete after 1.048 msecs
+ PM: noirq suspend of devices complete after 0.756 msecs
+ Disabling non-boot CPUs ...
+ CPU1: shutdown
+ CPU2: shutdown
+ CPU3: shutdown
+ Entering suspend state LP1
+ Enabling non-boot CPUs ...
+ CPU1 is up
+ CPU2 is up
+ CPU3 is up
+ PM: noirq resume of devices complete after 0.487 msecs
+ as3722 4-0040: Failed to read IRQ status: -16
+ as3722 4-0040: Failed to read IRQ status: -16
+ as3722 4-0040: Failed to read IRQ status: -16
+ as3722 4-0040: Failed to read IRQ status: -16
+ ...
+
+The reason why the as3722 interrupt status cannot be read is because the
+as3722 interrupt is not masked during suspend and when the as3722-rtc
+interrupt occurs, to wake-up the device, the interrupt is seen before the
+i2c controller has been resumed in order to read the as3722 interrupt
+status.
+
+The as3722-rtc driver sets it's interrupt as a wake-up source during
+suspend, which gets propagated to the parent as3722 interrupt. However,
+the as3722-rtc driver cannot disable it's interrupt during suspend
+otherwise we would never be woken up and so the as3722 must disable it's
+interrupt instead.
+
+Fix this by disabling the as3722 interrupt during suspend. To ensure that
+a wake-up event from the as3722 is not missing, enable the as3722 interrupt
+as a wake-up source before disabling the interrupt on entering suspend.
+
+Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
+Signed-off-by: Lee Jones <lee.jones@linaro.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/mfd/as3722.c | 30 ++++++++++++++++++++++++++++++
+ 1 file changed, 30 insertions(+)
+
+--- a/drivers/mfd/as3722.c
++++ b/drivers/mfd/as3722.c
+@@ -405,6 +405,8 @@ static int as3722_i2c_probe(struct i2c_c
+ goto scrub;
+ }
+
++ device_init_wakeup(as3722->dev, true);
++
+ dev_dbg(as3722->dev, "AS3722 core driver initialized successfully\n");
+ return 0;
+
+@@ -422,6 +424,29 @@ static int as3722_i2c_remove(struct i2c_
+ return 0;
+ }
+
++static int as3722_i2c_suspend(struct device *dev)
++{
++ struct as3722 *as3722 = dev_get_drvdata(dev);
++
++ if (device_may_wakeup(dev))
++ enable_irq_wake(as3722->chip_irq);
++ disable_irq(as3722->chip_irq);
++
++ return 0;
++}
++
++static int as3722_i2c_resume(struct device *dev)
++{
++ struct as3722 *as3722 = dev_get_drvdata(dev);
++
++ enable_irq(as3722->chip_irq);
++
++ if (device_may_wakeup(dev))
++ disable_irq_wake(as3722->chip_irq);
++
++ return 0;
++}
++
+ static const struct of_device_id as3722_of_match[] = {
+ { .compatible = "ams,as3722", },
+ {},
+@@ -434,10 +459,15 @@ static const struct i2c_device_id as3722
+ };
+ MODULE_DEVICE_TABLE(i2c, as3722_i2c_id);
+
++static const struct dev_pm_ops as3722_pm_ops = {
++ SET_SYSTEM_SLEEP_PM_OPS(as3722_i2c_suspend, as3722_i2c_resume)
++};
++
+ static struct i2c_driver as3722_i2c_driver = {
+ .driver = {
+ .name = "as3722",
+ .of_match_table = as3722_of_match,
++ .pm = &as3722_pm_ops,
+ },
+ .probe = as3722_i2c_probe,
+ .remove = as3722_i2c_remove,
--- /dev/null
+From a7b956fd38dd217dd78e3058110929f5ac914df1 Mon Sep 17 00:00:00 2001
+From: Arnd Bergmann <arnd@arndb.de>
+Date: Tue, 8 Dec 2015 16:21:05 +0100
+Subject: mfd: as3722: Mark PM functions as __maybe_unused
+
+From: Arnd Bergmann <arnd@arndb.de>
+
+commit a7b956fd38dd217dd78e3058110929f5ac914df1 upstream.
+
+The newly introduced as3722_i2c_suspend/resume functions are built
+unconditionally, but only used when power management is enabled,
+so we get a warning otherwise:
+
+drivers/mfd/as3722.c:427:12: warning: 'as3722_i2c_suspend' defined but not used [-Wunused-function]
+drivers/mfd/as3722.c:438:12: warning: 'as3722_i2c_resume' defined but not used [-Wunused-function]
+
+This marks them both as __maybe_unused, which avoids an ugly #ifdef
+and gives us best compile-time coverage. When they are unused, the
+compiler will silently drop the functions from its output.
+
+Signed-off-by: Arnd Bergmann <arnd@arndb.de>
+Fixes: 35deff7eb212 ("mfd: as3722: Handle interrupts on suspend")
+Signed-off-by: Lee Jones <lee.jones@linaro.org>
+Cc: Jon Hunter <jonathanh@nvidia.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ drivers/mfd/as3722.c | 4 ++--
+ 1 file changed, 2 insertions(+), 2 deletions(-)
+
+--- a/drivers/mfd/as3722.c
++++ b/drivers/mfd/as3722.c
+@@ -424,7 +424,7 @@ static int as3722_i2c_remove(struct i2c_
+ return 0;
+ }
+
+-static int as3722_i2c_suspend(struct device *dev)
++static int __maybe_unused as3722_i2c_suspend(struct device *dev)
+ {
+ struct as3722 *as3722 = dev_get_drvdata(dev);
+
+@@ -435,7 +435,7 @@ static int as3722_i2c_suspend(struct dev
+ return 0;
+ }
+
+-static int as3722_i2c_resume(struct device *dev)
++static int __maybe_unused as3722_i2c_resume(struct device *dev)
+ {
+ struct as3722 *as3722 = dev_get_drvdata(dev);
+
projects / thirdparty / kernel / stable-queue.git / commitdiff
