USB: Prevent system suspend when HSIC device is active
Some buses like HSIC would like to keep device in suspend state
after system resume. The remote wakeup or interface activity
later will auto resume the device. This will work only if the
device is auto suspended before system suspend. If the device
runtime state had been active during system suspend and system
suspend routine put the device in suspend, it will not be resumed
during system resume. When remote wakeup happen for this device,
the runtime resume will not bring the device to active as runtime
core think it is already active.
The HSIC bus ensure that device is auto suspended prior to system
suspend by holding a wakelock till the bus is suspended. HSIC bus
is not handling the case where device is auto resumed immediately
after system suspend begins. HSIC bus simply put the device into
suspend in system suspend routine.
This patch fixes above issue by returning an error code if the device
is not auto suspended during system suspend. Also add a safe guard
check in HSIC system resume routine to skip device resume only if it
is auto suspended prior to system suspend.
(cherry picked from commit 41d004c4eaa5565cb8d9113862c3cef1e51be648)
CRs-Fixed: 422876
Change-Id: I07063d1fe2ef054adc5c593691d417272e66221e
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Neha Pandey <nehap@codeaurora.org>
diff --git a/drivers/usb/host/ehci-msm-hsic.c b/drivers/usb/host/ehci-msm-hsic.c
index 3ec0098..e186140 100644
--- a/drivers/usb/host/ehci-msm-hsic.c
+++ b/drivers/usb/host/ehci-msm-hsic.c
@@ -1809,7 +1809,8 @@
* when remote wakeup is received or interface driver
* start I/O.
*/
- if (!atomic_read(&mehci->pm_usage_cnt))
+ if (!atomic_read(&mehci->pm_usage_cnt) &&
+ pm_runtime_suspended(dev))
return 0;
ret = msm_hsic_resume(mehci);