[PATCH v9] ARM: omap: edma: add suspend resume hook

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Daniel Mack]

This patch makes the edma driver resume correctly after suspend. Tested
on an AM33xx platform with cyclic audio streams and omap_hsmmc.

All information can be reconstructed by already known runtime
information.

As we now use some functions that were previously only used from __init
context, annotations had to be dropped.

[nm at ti.com: added error handling for runtime + suspend_late/early_resume]
Signed-off-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Daniel Mack <zonque@gmail.com>
Tested-by: Joel Fernandes <joelf@ti.com>
Acked-by: Joel Fernandes <joelf@ti.com>
---
Changes from v8:

	* Drop the edma_suspend hook altogether. Even though back then
	  when I wrote the code I was sure disabling the interrupts
	  during suspend is necessary, tests now show it in fact isn't.
	  My test setup still works if that code is omitted.
	* Use SET_LATE_SYSTEM_SLEEP_PM_OPS in the dev_pm_ops
	  declaration.

	Thanks to Sekhar for pointing out the above.

 arch/arm/common/edma.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 58 insertions(+), 2 deletions(-)

diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
index 485be42..c623dd0 100644
--- a/arch/arm/common/edma.c
+++ b/arch/arm/common/edma.c
@@ -244,6 +244,8 @@ struct edma {
 	/* list of channels with no even trigger; terminated by "-1" */
 	const s8	*noevent;
 
+	struct edma_soc_info *info;
+
 	/* The edma_inuse bit for each PaRAM slot is clear unless the
 	 * channel is in use ... by ARM or DSP, for QDMA, or whatever.
 	 */
@@ -295,7 +297,7 @@ static void map_dmach_queue(unsigned ctlr, unsigned ch_no,
 			~(0x7 << bit), queue_no << bit);
 }
 
-static void __init assign_priority_to_queue(unsigned ctlr, int queue_no,
+static void assign_priority_to_queue(unsigned ctlr, int queue_no,
 		int priority)
 {
 	int bit = queue_no * 4;
@@ -314,7 +316,7 @@ static void __init assign_priority_to_queue(unsigned ctlr, int queue_no,
  * included in that particular EDMA variant (Eg : dm646x)
  *
  */
-static void __init map_dmach_param(unsigned ctlr)
+static void map_dmach_param(unsigned ctlr)
 {
 	int i;
 	for (i = 0; i < EDMA_MAX_DMACH; i++)
@@ -1762,15 +1764,69 @@ static int edma_probe(struct platform_device *pdev)
 			edma_write_array2(j, EDMA_DRAE, i, 1, 0x0);
 			edma_write_array(j, EDMA_QRAE, i, 0x0);
 		}
+		edma_cc[j]->info = info[j];
 		arch_num_cc++;
 	}
 
 	return 0;
 }
 
+static int edma_pm_resume(struct device *dev)
+{
+	int i, j, r;
+
+	r = pm_runtime_get_sync(dev);
+	if (r < 0) {
+		dev_err(dev, "%s: get_sync returned %d\n", __func__, r);
+		return r;
+	}
+
+	for (j = 0; j < arch_num_cc; j++) {
+		struct edma *cc = edma_cc[j];
+
+		s8 (*queue_priority_mapping)[2];
+
+		queue_priority_mapping = cc->info->queue_priority_mapping;
+
+		/* Event queue priority mapping */
+		for (i = 0; queue_priority_mapping[i][0] != -1; i++)
+			assign_priority_to_queue(j,
+						 queue_priority_mapping[i][0],
+						 queue_priority_mapping[i][1]);
+
+		/*
+		 * Map the channel to param entry if channel mapping logic
+		 * exist
+		 */
+		if (edma_read(j, EDMA_CCCFG) & CHMAP_EXIST)
+			map_dmach_param(j);
+
+		for (i = 0; i < cc->num_channels; i++) {
+			if (test_bit(i, cc->edma_inuse)) {
+				/* ensure access through shadow region 0 */
+				edma_or_array2(j, EDMA_DRAE, 0, i >> 5,
+					       BIT(i & 0x1f));
+
+				setup_dma_interrupt(i,
+						    cc->intr_data[i].callback,
+						    cc->intr_data[i].data);
+			}
+		}
+	}
+
+	pm_runtime_put_sync(dev);
+
+	return 0;
+}
+
+static const struct dev_pm_ops edma_pm_ops = {
+	SET_LATE_SYSTEM_SLEEP_PM_OPS(NULL, edma_pm_resume)
+};
+
 static struct platform_driver edma_driver = {
 	.driver = {
 		.name	= "edma",
+		.pm	= &edma_pm_ops,
 		.of_match_table = edma_of_ids,
 	},
 	.probe = edma_probe,
-- 
2.1.0

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Dave Gerlach]

On 08/26/2014 03:52 AM, Daniel Mack wrote:
> This patch makes the edma driver resume correctly after suspend. Tested
> on an AM33xx platform with cyclic audio streams and omap_hsmmc.
> 
> All information can be reconstructed by already known runtime
> information.
> 
> As we now use some functions that were previously only used from __init
> context, annotations had to be dropped.
> 
> [nm at ti.com: added error handling for runtime + suspend_late/early_resume]
> Signed-off-by: Nishanth Menon <nm@ti.com>
> Signed-off-by: Daniel Mack <zonque@gmail.com>
> Tested-by: Joel Fernandes <joelf@ti.com>
> Acked-by: Joel Fernandes <joelf@ti.com>
> ---
> Changes from v8:
> 
> 	* Drop the edma_suspend hook altogether. Even though back then
> 	  when I wrote the code I was sure disabling the interrupts
> 	  during suspend is necessary, tests now show it in fact isn't.
> 	  My test setup still works if that code is omitted.
> 	* Use SET_LATE_SYSTEM_SLEEP_PM_OPS in the dev_pm_ops
> 	  declaration.
> 
> 	Thanks to Sekhar for pointing out the above.
> 
>  arch/arm/common/edma.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 58 insertions(+), 2 deletions(-)

Doesn't seem to be any comments here, any chance this can be picked up? This
patch always seems to get missed but will be needed for suspend/resume on both
AM335x and AM437x.

Regards,
Dave

> 
> diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
> index 485be42..c623dd0 100644
> --- a/arch/arm/common/edma.c
> +++ b/arch/arm/common/edma.c
> @@ -244,6 +244,8 @@ struct edma {
>  	/* list of channels with no even trigger; terminated by "-1" */
>  	const s8	*noevent;
>  
> +	struct edma_soc_info *info;
> +
>  	/* The edma_inuse bit for each PaRAM slot is clear unless the
>  	 * channel is in use ... by ARM or DSP, for QDMA, or whatever.
>  	 */
> @@ -295,7 +297,7 @@ static void map_dmach_queue(unsigned ctlr, unsigned ch_no,
>  			~(0x7 << bit), queue_no << bit);
>  }
>  
> -static void __init assign_priority_to_queue(unsigned ctlr, int queue_no,
> +static void assign_priority_to_queue(unsigned ctlr, int queue_no,
>  		int priority)
>  {
>  	int bit = queue_no * 4;
> @@ -314,7 +316,7 @@ static void __init assign_priority_to_queue(unsigned ctlr, int queue_no,
>   * included in that particular EDMA variant (Eg : dm646x)
>   *
>   */
> -static void __init map_dmach_param(unsigned ctlr)
> +static void map_dmach_param(unsigned ctlr)
>  {
>  	int i;
>  	for (i = 0; i < EDMA_MAX_DMACH; i++)
> @@ -1762,15 +1764,69 @@ static int edma_probe(struct platform_device *pdev)
>  			edma_write_array2(j, EDMA_DRAE, i, 1, 0x0);
>  			edma_write_array(j, EDMA_QRAE, i, 0x0);
>  		}
> +		edma_cc[j]->info = info[j];
>  		arch_num_cc++;
>  	}
>  
>  	return 0;
>  }
>  
> +static int edma_pm_resume(struct device *dev)
> +{
> +	int i, j, r;
> +
> +	r = pm_runtime_get_sync(dev);
> +	if (r < 0) {
> +		dev_err(dev, "%s: get_sync returned %d\n", __func__, r);
> +		return r;
> +	}
> +
> +	for (j = 0; j < arch_num_cc; j++) {
> +		struct edma *cc = edma_cc[j];
> +
> +		s8 (*queue_priority_mapping)[2];
> +
> +		queue_priority_mapping = cc->info->queue_priority_mapping;
> +
> +		/* Event queue priority mapping */
> +		for (i = 0; queue_priority_mapping[i][0] != -1; i++)
> +			assign_priority_to_queue(j,
> +						 queue_priority_mapping[i][0],
> +						 queue_priority_mapping[i][1]);
> +
> +		/*
> +		 * Map the channel to param entry if channel mapping logic
> +		 * exist
> +		 */
> +		if (edma_read(j, EDMA_CCCFG) & CHMAP_EXIST)
> +			map_dmach_param(j);
> +
> +		for (i = 0; i < cc->num_channels; i++) {
> +			if (test_bit(i, cc->edma_inuse)) {
> +				/* ensure access through shadow region 0 */
> +				edma_or_array2(j, EDMA_DRAE, 0, i >> 5,
> +					       BIT(i & 0x1f));
> +
> +				setup_dma_interrupt(i,
> +						    cc->intr_data[i].callback,
> +						    cc->intr_data[i].data);
> +			}
> +		}
> +	}
> +
> +	pm_runtime_put_sync(dev);
> +
> +	return 0;
> +}
> +
> +static const struct dev_pm_ops edma_pm_ops = {
> +	SET_LATE_SYSTEM_SLEEP_PM_OPS(NULL, edma_pm_resume)
> +};
> +
>  static struct platform_driver edma_driver = {
>  	.driver = {
>  		.name	= "edma",
> +		.pm	= &edma_pm_ops,
>  		.of_match_table = edma_of_ids,
>  	},
>  	.probe = edma_probe,
> 

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Sekhar Nori]

On Wednesday 05 November 2014 09:27 PM, Dave Gerlach wrote:
> On 08/26/2014 03:52 AM, Daniel Mack wrote:
>> This patch makes the edma driver resume correctly after suspend. Tested
>> on an AM33xx platform with cyclic audio streams and omap_hsmmc.
>>
>> All information can be reconstructed by already known runtime
>> information.
>>
>> As we now use some functions that were previously only used from __init
>> context, annotations had to be dropped.
>>
>> [nm at ti.com: added error handling for runtime + suspend_late/early_resume]
>> Signed-off-by: Nishanth Menon <nm@ti.com>
>> Signed-off-by: Daniel Mack <zonque@gmail.com>
>> Tested-by: Joel Fernandes <joelf@ti.com>
>> Acked-by: Joel Fernandes <joelf@ti.com>
>> ---
>> Changes from v8:
>>
>> 	* Drop the edma_suspend hook altogether. Even though back then
>> 	  when I wrote the code I was sure disabling the interrupts
>> 	  during suspend is necessary, tests now show it in fact isn't.
>> 	  My test setup still works if that code is omitted.
>> 	* Use SET_LATE_SYSTEM_SLEEP_PM_OPS in the dev_pm_ops
>> 	  declaration.
>>
>> 	Thanks to Sekhar for pointing out the above.
>>
>>  arch/arm/common/edma.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++--
>>  1 file changed, 58 insertions(+), 2 deletions(-)
> 
> Doesn't seem to be any comments here, any chance this can be picked up? This
> patch always seems to get missed but will be needed for suspend/resume on both
> AM335x and AM437x.

Dave, do you have a branch against mainline with suspend working on any
of these SoCs using which I can test this patch?

Thanks,
Sekhar

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Dave Gerlach]

Sekhar,
On 11/05/2014 10:04 AM, Sekhar Nori wrote:
> On Wednesday 05 November 2014 09:27 PM, Dave Gerlach wrote:
>> On 08/26/2014 03:52 AM, Daniel Mack wrote:
>>> This patch makes the edma driver resume correctly after suspend. Tested
>>> on an AM33xx platform with cyclic audio streams and omap_hsmmc.
>>>
>>> All information can be reconstructed by already known runtime
>>> information.
>>>
>>> As we now use some functions that were previously only used from __init
>>> context, annotations had to be dropped.
>>>
>>> [nm at ti.com: added error handling for runtime + suspend_late/early_resume]
>>> Signed-off-by: Nishanth Menon <nm@ti.com>
>>> Signed-off-by: Daniel Mack <zonque@gmail.com>
>>> Tested-by: Joel Fernandes <joelf@ti.com>
>>> Acked-by: Joel Fernandes <joelf@ti.com>
>>> ---
>>> Changes from v8:
>>>
>>> 	* Drop the edma_suspend hook altogether. Even though back then
>>> 	  when I wrote the code I was sure disabling the interrupts
>>> 	  during suspend is necessary, tests now show it in fact isn't.
>>> 	  My test setup still works if that code is omitted.
>>> 	* Use SET_LATE_SYSTEM_SLEEP_PM_OPS in the dev_pm_ops
>>> 	  declaration.
>>>
>>> 	Thanks to Sekhar for pointing out the above.
>>>
>>>  arch/arm/common/edma.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++--
>>>  1 file changed, 58 insertions(+), 2 deletions(-)
>>
>> Doesn't seem to be any comments here, any chance this can be picked up? This
>> patch always seems to get missed but will be needed for suspend/resume on both
>> AM335x and AM437x.
> 
> Dave, do you have a branch against mainline with suspend working on any
> of these SoCs using which I can test this patch?

Yes, here is WIP of next version with all required patches + this one.
https://github.com/dgerlach/linux-pm/tree/pm-ds0-v3.18-rc3-WIP

For suspend to work you need to select:

CONFIG_WKUP_M3_IPC=y
CONFIG_WKUP_M3_RPROC=y

And you need to enable USB for multiple suspends to work.

You can get am335x-pm-firmware.elf FW here from HEAD:
https://git.ti.com/ti-cm3-pm-firmware/amx3-cm3/commits/next

You can place in /lib/firmware and select CONFIG_FW_LOADER_USER_HELPER_FALLBACK
or build into kernel.

Also for what it's worth you can have my tested by:

Tested-by: Dave Gerlach <d-gerlach@ti.com>

I have tested on am335x-boneblack, am335x-evm, and am335x-evmsk, multiple
suspend cycles work with no issue.

Regards,
Dave

> 
> Thanks,
> Sekhar
> 

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Sekhar Nori]

On Wednesday 05 November 2014 11:40 PM, Dave Gerlach wrote:
> Sekhar,
> On 11/05/2014 10:04 AM, Sekhar Nori wrote:
>> On Wednesday 05 November 2014 09:27 PM, Dave Gerlach wrote:
>>> On 08/26/2014 03:52 AM, Daniel Mack wrote:
>>>> This patch makes the edma driver resume correctly after suspend. Tested
>>>> on an AM33xx platform with cyclic audio streams and omap_hsmmc.
>>>>
>>>> All information can be reconstructed by already known runtime
>>>> information.
>>>>
>>>> As we now use some functions that were previously only used from __init
>>>> context, annotations had to be dropped.
>>>>
>>>> [nm at ti.com: added error handling for runtime + suspend_late/early_resume]
>>>> Signed-off-by: Nishanth Menon <nm@ti.com>
>>>> Signed-off-by: Daniel Mack <zonque@gmail.com>
>>>> Tested-by: Joel Fernandes <joelf@ti.com>
>>>> Acked-by: Joel Fernandes <joelf@ti.com>
>>>> ---
>>>> Changes from v8:
>>>>
>>>> 	* Drop the edma_suspend hook altogether. Even though back then
>>>> 	  when I wrote the code I was sure disabling the interrupts
>>>> 	  during suspend is necessary, tests now show it in fact isn't.
>>>> 	  My test setup still works if that code is omitted.
>>>> 	* Use SET_LATE_SYSTEM_SLEEP_PM_OPS in the dev_pm_ops
>>>> 	  declaration.
>>>>
>>>> 	Thanks to Sekhar for pointing out the above.
>>>>
>>>>  arch/arm/common/edma.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++--
>>>>  1 file changed, 58 insertions(+), 2 deletions(-)
>>>
>>> Doesn't seem to be any comments here, any chance this can be picked up? This
>>> patch always seems to get missed but will be needed for suspend/resume on both
>>> AM335x and AM437x.
>>
>> Dave, do you have a branch against mainline with suspend working on any
>> of these SoCs using which I can test this patch?
> 
> Yes, here is WIP of next version with all required patches + this one.
> https://github.com/dgerlach/linux-pm/tree/pm-ds0-v3.18-rc3-WIP
> 
> For suspend to work you need to select:
> 
> CONFIG_WKUP_M3_IPC=y
> CONFIG_WKUP_M3_RPROC=y

I get this:

arch/arm/mach-omap2/pm33xx.c:28:31: fatal error: linux/wkup_m3_ipc.h: No such file or directory
 #include <linux/wkup_m3_ipc.h>
                               ^
compilation terminated.
make[1]: *** [arch/arm/mach-omap2/pm33xx.o] Error 1

Forgot to commit wkup_m3_ipc.h?

Thanks,
Sekhar
 

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Dave Gerlach]

Sekhar,
On 11/06/2014 02:33 AM, Sekhar Nori wrote:
> On Wednesday 05 November 2014 11:40 PM, Dave Gerlach wrote:
>> Sekhar,
>> On 11/05/2014 10:04 AM, Sekhar Nori wrote:
>>> On Wednesday 05 November 2014 09:27 PM, Dave Gerlach wrote:
>>>> On 08/26/2014 03:52 AM, Daniel Mack wrote:
>>>>> This patch makes the edma driver resume correctly after suspend. Tested
>>>>> on an AM33xx platform with cyclic audio streams and omap_hsmmc.
>>>>>
>>>>> All information can be reconstructed by already known runtime
>>>>> information.
>>>>>
>>>>> As we now use some functions that were previously only used from __init
>>>>> context, annotations had to be dropped.
>>>>>
>>>>> [nm at ti.com: added error handling for runtime + suspend_late/early_resume]
>>>>> Signed-off-by: Nishanth Menon <nm@ti.com>
>>>>> Signed-off-by: Daniel Mack <zonque@gmail.com>
>>>>> Tested-by: Joel Fernandes <joelf@ti.com>
>>>>> Acked-by: Joel Fernandes <joelf@ti.com>
>>>>> ---
>>>>> Changes from v8:
>>>>>
>>>>> 	* Drop the edma_suspend hook altogether. Even though back then
>>>>> 	  when I wrote the code I was sure disabling the interrupts
>>>>> 	  during suspend is necessary, tests now show it in fact isn't.
>>>>> 	  My test setup still works if that code is omitted.
>>>>> 	* Use SET_LATE_SYSTEM_SLEEP_PM_OPS in the dev_pm_ops
>>>>> 	  declaration.
>>>>>
>>>>> 	Thanks to Sekhar for pointing out the above.
>>>>>
>>>>>  arch/arm/common/edma.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++--
>>>>>  1 file changed, 58 insertions(+), 2 deletions(-)
>>>>
>>>> Doesn't seem to be any comments here, any chance this can be picked up? This
>>>> patch always seems to get missed but will be needed for suspend/resume on both
>>>> AM335x and AM437x.
>>>
>>> Dave, do you have a branch against mainline with suspend working on any
>>> of these SoCs using which I can test this patch?
>>
>> Yes, here is WIP of next version with all required patches + this one.
>> https://github.com/dgerlach/linux-pm/tree/pm-ds0-v3.18-rc3-WIP
>>
>> For suspend to work you need to select:
>>
>> CONFIG_WKUP_M3_IPC=y
>> CONFIG_WKUP_M3_RPROC=y
> 
> I get this:
> 
> arch/arm/mach-omap2/pm33xx.c:28:31: fatal error: linux/wkup_m3_ipc.h: No such file or directory
>  #include <linux/wkup_m3_ipc.h>
>                                ^
> compilation terminated.
> make[1]: *** [arch/arm/mach-omap2/pm33xx.o] Error 1
> 
> Forgot to commit wkup_m3_ipc.h?
> 

Ahhh sorry about that, looks like I dropped it during a rebase. Added it in a
patch and pushed that on top of the tree from yesterday. Sorry again!.

Regards,
Dave


> Thanks,
> Sekhar
>  
> 

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Sekhar Nori]

On Tuesday 26 August 2014 02:22 PM, Daniel Mack wrote:
> This patch makes the edma driver resume correctly after suspend. Tested
> on an AM33xx platform with cyclic audio streams and omap_hsmmc.
> 
> All information can be reconstructed by already known runtime
> information.
> 
> As we now use some functions that were previously only used from __init
> context, annotations had to be dropped.
> 
> [nm at ti.com: added error handling for runtime + suspend_late/early_resume]
> Signed-off-by: Nishanth Menon <nm@ti.com>
> Signed-off-by: Daniel Mack <zonque@gmail.com>
> Tested-by: Joel Fernandes <joelf@ti.com>
> Acked-by: Joel Fernandes <joelf@ti.com>
> ---
> Changes from v8:
> 
> 	* Drop the edma_suspend hook altogether. Even though back then
> 	  when I wrote the code I was sure disabling the interrupts
> 	  during suspend is necessary, tests now show it in fact isn't.
> 	  My test setup still works if that code is omitted.
> 	* Use SET_LATE_SYSTEM_SLEEP_PM_OPS in the dev_pm_ops
> 	  declaration.
> 
> 	Thanks to Sekhar for pointing out the above.
> 
>  arch/arm/common/edma.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++--
>  1 file changed, 58 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
> index 485be42..c623dd0 100644
> --- a/arch/arm/common/edma.c
> +++ b/arch/arm/common/edma.c
> @@ -244,6 +244,8 @@ struct edma {
>  	/* list of channels with no even trigger; terminated by "-1" */
>  	const s8	*noevent;
>  
> +	struct edma_soc_info *info;
> +
>  	/* The edma_inuse bit for each PaRAM slot is clear unless the
>  	 * channel is in use ... by ARM or DSP, for QDMA, or whatever.
>  	 */
> @@ -295,7 +297,7 @@ static void map_dmach_queue(unsigned ctlr, unsigned ch_no,
>  			~(0x7 << bit), queue_no << bit);
>  }
>  
> -static void __init assign_priority_to_queue(unsigned ctlr, int queue_no,
> +static void assign_priority_to_queue(unsigned ctlr, int queue_no,
>  		int priority)
>  {
>  	int bit = queue_no * 4;
> @@ -314,7 +316,7 @@ static void __init assign_priority_to_queue(unsigned ctlr, int queue_no,
>   * included in that particular EDMA variant (Eg : dm646x)
>   *
>   */
> -static void __init map_dmach_param(unsigned ctlr)
> +static void map_dmach_param(unsigned ctlr)
>  {
>  	int i;
>  	for (i = 0; i < EDMA_MAX_DMACH; i++)
> @@ -1762,15 +1764,69 @@ static int edma_probe(struct platform_device *pdev)
>  			edma_write_array2(j, EDMA_DRAE, i, 1, 0x0);
>  			edma_write_array(j, EDMA_QRAE, i, 0x0);
>  		}
> +		edma_cc[j]->info = info[j];
>  		arch_num_cc++;
>  	}
>  
>  	return 0;
>  }
>  
> +static int edma_pm_resume(struct device *dev)
> +{
> +	int i, j, r;
> +
> +	r = pm_runtime_get_sync(dev);

I think I have asked this before, and I am still not sure why this call 
to pm_runtime_get_sync() is needed here. From my testing today, this 
does seem to be a a no-op and this call returns from rpm_resume() 
because of this check:

	else if (dev->power.disable_depth == 1 && dev->power.is_suspended
	    && dev->power.runtime_status == RPM_ACTIVE)
		retval = 1;

So, AFAICS, the net effect is an increment of dev->power.usage_count
(which is already greater than 0) and its subsequent decrement at the
end of the function.

After removing this call I did not see any EDMA malfunction as well 
(can access MMC/SD just fine after suspend/resume cycle).

So, any objections to merging this patch with the attached hunk 
applied?

Thanks,
Sekhar

---8<---
diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
index 1f492d5be9c0..79de6a23047b 100644
--- a/arch/arm/common/edma.c
+++ b/arch/arm/common/edma.c
@@ -1803,13 +1803,7 @@ static int edma_probe(struct platform_device *pdev)
 
 static int edma_pm_resume(struct device *dev)
 {
-       int i, j, r;
-
-       r = pm_runtime_get_sync(dev);
-       if (r < 0) {
-               dev_err(dev, "%s: get_sync returned %d\n", __func__, r);
-               return r;
-       }
+       int i, j;
 
        for (j = 0; j < arch_num_cc; j++) {
                struct edma *cc = edma_cc[j];
@@ -1844,8 +1838,6 @@ static int edma_pm_resume(struct device *dev)
                }
        }
 
-       pm_runtime_put_sync(dev);
-
        return 0;
 }

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Daniel Mack]

Hi Sekhar,

On 11/14/2014 06:03 PM, Sekhar Nori wrote:
> I think I have asked this before, and I am still not sure why this call 
> to pm_runtime_get_sync() is needed here. From my testing today, this 
> does seem to be a a no-op and this call returns from rpm_resume() 
> because of this check:
> 
> 	else if (dev->power.disable_depth == 1 && dev->power.is_suspended
> 	    && dev->power.runtime_status == RPM_ACTIVE)
> 		retval = 1;

Yes. IIRC, it was in fact not needed.

> So, AFAICS, the net effect is an increment of dev->power.usage_count
> (which is already greater than 0) and its subsequent decrement at the
> end of the function.
> 
> After removing this call I did not see any EDMA malfunction as well 
> (can access MMC/SD just fine after suspend/resume cycle).
> 
> So, any objections to merging this patch with the attached hunk 
> applied?

Looks good to me, we can still add it back later if it turns out to be
needed.


Thanks,
Daniel


> Thanks,
> Sekhar
> 
> ---8<---
> diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
> index 1f492d5be9c0..79de6a23047b 100644
> --- a/arch/arm/common/edma.c
> +++ b/arch/arm/common/edma.c
> @@ -1803,13 +1803,7 @@ static int edma_probe(struct platform_device *pdev)
>  
>  static int edma_pm_resume(struct device *dev)
>  {
> -       int i, j, r;
> -
> -       r = pm_runtime_get_sync(dev);
> -       if (r < 0) {
> -               dev_err(dev, "%s: get_sync returned %d\n", __func__, r);
> -               return r;
> -       }
> +       int i, j;
>  
>         for (j = 0; j < arch_num_cc; j++) {
>                 struct edma *cc = edma_cc[j];
> @@ -1844,8 +1838,6 @@ static int edma_pm_resume(struct device *dev)
>                 }
>         }
>  
> -       pm_runtime_put_sync(dev);
> -
>         return 0;
>  }
> 
> 

[PATCH v9] ARM: omap: edma: add suspend resume hook

[Sekhar Nori]

On Friday 14 November 2014 10:37 PM, Daniel Mack wrote:
> Hi Sekhar,
> 
> On 11/14/2014 06:03 PM, Sekhar Nori wrote:
>> I think I have asked this before, and I am still not sure why this call 
>> to pm_runtime_get_sync() is needed here. From my testing today, this 
>> does seem to be a a no-op and this call returns from rpm_resume() 
>> because of this check:
>>
>> 	else if (dev->power.disable_depth == 1 && dev->power.is_suspended
>> 	    && dev->power.runtime_status == RPM_ACTIVE)
>> 		retval = 1;
> 
> Yes. IIRC, it was in fact not needed.
> 
>> So, AFAICS, the net effect is an increment of dev->power.usage_count
>> (which is already greater than 0) and its subsequent decrement at the
>> end of the function.
>>
>> After removing this call I did not see any EDMA malfunction as well 
>> (can access MMC/SD just fine after suspend/resume cycle).
>>
>> So, any objections to merging this patch with the attached hunk 
>> applied?
> 
> Looks good to me, we can still add it back later if it turns out to be
> needed.

Okay, thanks for the confirmation.

Regards,
Sekhar