diff mbox

i2c: qup: skip qup_i2c_suspend if the device is already runtime suspended

Message ID 1472124219-1627-1-git-send-email-sudeep.holla@arm.com
State Accepted
Headers show

Commit Message

Sudeep Holla Aug. 25, 2016, 11:23 a.m. UTC
If the i2c device is already runtime suspended, if qup_i2c_suspend is
executed during suspend-to-idle or suspend-to-ram it will result in the
following splat:

WARNING: CPU: 3 PID: 1593 at drivers/clk/clk.c:476 clk_core_unprepare+0x80/0x90
Modules linked in:

CPU: 3 PID: 1593 Comm: bash Tainted: G        W       4.8.0-rc3 #14
Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
PC is at clk_core_unprepare+0x80/0x90
LR is at clk_unprepare+0x28/0x40
pc : [<ffff0000086eecf0>] lr : [<ffff0000086f0c58>] pstate: 60000145
Call trace:
 clk_core_unprepare+0x80/0x90
 qup_i2c_disable_clocks+0x2c/0x68
 qup_i2c_suspend+0x10/0x20
 platform_pm_suspend+0x24/0x68
 dpm_run_callback.isra.7+0x1c/0x70
 __device_suspend+0xf4/0x298
 dpm_suspend+0x10c/0x228
 dpm_suspend_start+0x68/0x78
 suspend_devices_and_enter+0xb8/0x460
 pm_suspend+0x1ec/0x240
 state_store+0x84/0xf8
 kobj_attr_store+0x14/0x28
 sysfs_kf_write+0x48/0x58
 kernfs_fop_write+0x15c/0x1f8
 __vfs_write+0x1c/0x100
 vfs_write+0x9c/0x1b8
 SyS_write+0x44/0xa0
 el0_svc_naked+0x24/0x28

This patch fixes the issue by executing qup_i2c_pm_suspend_runtime
conditionally in qup_i2c_suspend.

Cc: Andy Gross <andy.gross@linaro.org>
Cc: David Brown <david.brown@linaro.org>
Cc: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
---
 drivers/i2c/busses/i2c-qup.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--
2.7.4

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Comments

Sudeep Holla Sept. 13, 2016, 12:38 p.m. UTC | #1
On Thu, Aug 25, 2016 at 12:23 PM, Sudeep Holla <sudeep.holla@arm.com> wrote:
> If the i2c device is already runtime suspended, if qup_i2c_suspend is
> executed during suspend-to-idle or suspend-to-ram it will result in the
> following splat:
>
> WARNING: CPU: 3 PID: 1593 at drivers/clk/clk.c:476 clk_core_unprepare+0x80/0x90
> Modules linked in:
>
> CPU: 3 PID: 1593 Comm: bash Tainted: G        W       4.8.0-rc3 #14
> Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
> PC is at clk_core_unprepare+0x80/0x90
> LR is at clk_unprepare+0x28/0x40
> pc : [<ffff0000086eecf0>] lr : [<ffff0000086f0c58>] pstate: 60000145
> Call trace:
>  clk_core_unprepare+0x80/0x90
>  qup_i2c_disable_clocks+0x2c/0x68
>  qup_i2c_suspend+0x10/0x20
>  platform_pm_suspend+0x24/0x68
>  dpm_run_callback.isra.7+0x1c/0x70
>  __device_suspend+0xf4/0x298
>  dpm_suspend+0x10c/0x228
>  dpm_suspend_start+0x68/0x78
>  suspend_devices_and_enter+0xb8/0x460
>  pm_suspend+0x1ec/0x240
>  state_store+0x84/0xf8
>  kobj_attr_store+0x14/0x28
>  sysfs_kf_write+0x48/0x58
>  kernfs_fop_write+0x15c/0x1f8
>  __vfs_write+0x1c/0x100
>  vfs_write+0x9c/0x1b8
>  SyS_write+0x44/0xa0
>  el0_svc_naked+0x24/0x28
>
> This patch fixes the issue by executing qup_i2c_pm_suspend_runtime
> conditionally in qup_i2c_suspend.
>

Gentle ping !

Regards,
Sudeep
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Andy Gross Sept. 14, 2016, 5:33 p.m. UTC | #2
On Thu, Aug 25, 2016 at 12:23:39PM +0100, Sudeep Holla wrote:
> If the i2c device is already runtime suspended, if qup_i2c_suspend is
> executed during suspend-to-idle or suspend-to-ram it will result in the
> following splat:
> 
<snip>
> 
> This patch fixes the issue by executing qup_i2c_pm_suspend_runtime
> conditionally in qup_i2c_suspend.
> 
> Cc: Andy Gross <andy.gross@linaro.org>
> Cc: David Brown <david.brown@linaro.org>
> Cc: Wolfram Sang <wsa@the-dreams.de>
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

Reviewed-by: Andy Gross <andy.gross@linro.org>

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Wolfram Sang Sept. 22, 2016, 6:09 p.m. UTC | #3
On Thu, Aug 25, 2016 at 12:23:39PM +0100, Sudeep Holla wrote:
> If the i2c device is already runtime suspended, if qup_i2c_suspend is
> executed during suspend-to-idle or suspend-to-ram it will result in the
> following splat:
> 
> WARNING: CPU: 3 PID: 1593 at drivers/clk/clk.c:476 clk_core_unprepare+0x80/0x90
> Modules linked in:
> 
> CPU: 3 PID: 1593 Comm: bash Tainted: G        W       4.8.0-rc3 #14
> Hardware name: Qualcomm Technologies, Inc. APQ 8016 SBC (DT)
> PC is at clk_core_unprepare+0x80/0x90
> LR is at clk_unprepare+0x28/0x40
> pc : [<ffff0000086eecf0>] lr : [<ffff0000086f0c58>] pstate: 60000145
> Call trace:
>  clk_core_unprepare+0x80/0x90
>  qup_i2c_disable_clocks+0x2c/0x68
>  qup_i2c_suspend+0x10/0x20
>  platform_pm_suspend+0x24/0x68
>  dpm_run_callback.isra.7+0x1c/0x70
>  __device_suspend+0xf4/0x298
>  dpm_suspend+0x10c/0x228
>  dpm_suspend_start+0x68/0x78
>  suspend_devices_and_enter+0xb8/0x460
>  pm_suspend+0x1ec/0x240
>  state_store+0x84/0xf8
>  kobj_attr_store+0x14/0x28
>  sysfs_kf_write+0x48/0x58
>  kernfs_fop_write+0x15c/0x1f8
>  __vfs_write+0x1c/0x100
>  vfs_write+0x9c/0x1b8
>  SyS_write+0x44/0xa0
>  el0_svc_naked+0x24/0x28
> 
> This patch fixes the issue by executing qup_i2c_pm_suspend_runtime
> conditionally in qup_i2c_suspend.
> 
> Cc: Andy Gross <andy.gross@linaro.org>
> Cc: David Brown <david.brown@linaro.org>
> Cc: Wolfram Sang <wsa@the-dreams.de>
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

Applied to for-current, thanks!
Wolfram Sang Sept. 22, 2016, 6:10 p.m. UTC | #4
> > Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> 
> Reviewed-by: Andy Gross <andy.gross@linro.org>

I took the liberty to make "linaro" out of "linro".
diff mbox

Patch

diff --git a/drivers/i2c/busses/i2c-qup.c b/drivers/i2c/busses/i2c-qup.c
index 501bd15cb78e..a8497cfdae6f 100644
--- a/drivers/i2c/busses/i2c-qup.c
+++ b/drivers/i2c/busses/i2c-qup.c
@@ -1599,7 +1599,8 @@  static int qup_i2c_pm_resume_runtime(struct device *device)
 #ifdef CONFIG_PM_SLEEP
 static int qup_i2c_suspend(struct device *device)
 {
-	qup_i2c_pm_suspend_runtime(device);
+	if (!pm_runtime_suspended(device))
+		return qup_i2c_pm_suspend_runtime(device);
 	return 0;
 }