[PATCH v4 1/2] media: atmel-isi: add runtime pm support
Josh Wu
josh.wu at atmel.com
Tue May 26 02:58:14 PDT 2015
On 5/26/2015 5:14 PM, Josh Wu wrote:
> Hi, Laurent
>
> On 5/26/2015 4:16 PM, Laurent Pinchart wrote:
>> Hi Josh,
>>
>> Thank you for the patch.
>>
>> On Tuesday 26 May 2015 16:00:09 Josh Wu wrote:
>>> The runtime pm resume/suspend will enable/disable pclk (ISI peripheral
>>> clock).
>>> And we need to call runtime_pm_get_sync()/runtime_pm_put() when we need
>>> access ISI registers. In atmel_isi_probe(), remove the isi disable code
>>> as in the moment ISI peripheral clock is not enable yet.
>>>
>>> In the meantime, as clock_start()/clock_stop() is used to control the
>>> mclk not ISI peripheral clock. So move this to start[stop]_streaming()
>>> function.
>>>
>>> Signed-off-by: Josh Wu <josh.wu at atmel.com>
>>> ---
>>>
>>> Changes in v4:
>>> - need to call pm_runtime_disable() in atmel_isi_remove().
>>> - merged the patch which remove isi disable code in
>>> atmel_isi_probe() as
>>> isi peripherial clock is not enabled in this moment.
>>> - refine the commit log
>>>
>>> Changes in v3: None
>>> Changes in v2:
>>> - merged v1 two patch into one.
>>> - use runtime_pm_put() instead of runtime_pm_put_sync()
>>> - enable peripheral clock before access ISI registers.
>>>
>>> drivers/media/platform/soc_camera/atmel-isi.c | 54
>>> ++++++++++++++++++++----
>>> 1 file changed, 46 insertions(+), 8 deletions(-)
>>>
>>> diff --git a/drivers/media/platform/soc_camera/atmel-isi.c
>>> b/drivers/media/platform/soc_camera/atmel-isi.c index 2879026..194e875
>>> 100644
>>> --- a/drivers/media/platform/soc_camera/atmel-isi.c
>>> +++ b/drivers/media/platform/soc_camera/atmel-isi.c
>>> @@ -20,6 +20,7 @@
>>> #include <linux/kernel.h>
>>> #include <linux/module.h>
>>> #include <linux/platform_device.h>
>>> +#include <linux/pm_runtime.h>
>>> #include <linux/slab.h>
>>>
>>> #include <media/atmel-isi.h>
>>> @@ -386,6 +387,8 @@ static int start_streaming(struct vb2_queue *vq,
>>> unsigned int count) struct atmel_isi *isi = ici->priv;
>>> int ret;
>>>
>>> + pm_runtime_get_sync(ici->v4l2_dev.dev);
>>> +
>>> /* Reset ISI */
>>> ret = atmel_isi_wait_status(isi, WAIT_ISI_RESET);
>>> if (ret < 0) {
>> You need to call pm_runtime_put() in the error path, otherwise an
>> atmel_isi_wait_status() failure will keep the device enabled.
>
> Nice catch. Thanks.
>
>>
>>> @@ -445,6 +448,8 @@ static void stop_streaming(struct vb2_queue *vq)
>>> ret = atmel_isi_wait_status(isi, WAIT_ISI_DISABLE);
>>> if (ret < 0)
>>> dev_err(icd->parent, "Disable ISI timed out\n");
>>> +
>>> + pm_runtime_put(ici->v4l2_dev.dev);
>>> }
>>>
>>> static struct vb2_ops isi_video_qops = {
>>> @@ -516,7 +521,13 @@ static int isi_camera_set_fmt(struct
>>> soc_camera_device
>>> *icd, if (mf->code != xlate->code)
>>> return -EINVAL;
>>>
>>> + /* Enable PM and peripheral clock before operate isi registers */
>>> + pm_runtime_get_sync(ici->v4l2_dev.dev);
>>> +
>>> ret = configure_geometry(isi, pix->width, pix->height,
>>> xlate->code);
>>> +
>>> + pm_runtime_put(ici->v4l2_dev.dev);
>> I think it would simplify the code to move the configure_geometry()
>> call to
>> start_streaming() as you already call pm_runtime_get_sync() there.
>> That can be
>> done in a separate patch though.
>
> I think it's a good idea. I would like to make this in a separate
> patch and not include in this series.
>
> In summary, I'll resend this patch just with the fix you mentioned in
> above (fix the error path in start_streaming).
> Is that okay for you?
As I found another issue on stop_streaming(), so I sent a v5 series for
this whole patch set with a new fix.
Please check it.
BTW: I don't include the simplify method: move configure_geometry() into
start_streaming(), I perfer do that after this series is merged.
Best Regards,
Josh Wu
>
> Best Regards,
> Josh Wu
>
>>
>>> +
>>> if (ret < 0)
>>> return ret;
>>>
>>> @@ -736,14 +747,9 @@ static int isi_camera_clock_start(struct
>>> soc_camera_host *ici) struct atmel_isi *isi = ici->priv;
>>> int ret;
>>>
>>> - ret = clk_prepare_enable(isi->pclk);
>>> - if (ret)
>>> - return ret;
>>> -
>>> if (!IS_ERR(isi->mck)) {
>>> ret = clk_prepare_enable(isi->mck);
>>> if (ret) {
>>> - clk_disable_unprepare(isi->pclk);
>>> return ret;
>>> }
>>> }
>>> @@ -758,7 +764,6 @@ static void isi_camera_clock_stop(struct
>>> soc_camera_host
>>> *ici)
>>>
>>> if (!IS_ERR(isi->mck))
>>> clk_disable_unprepare(isi->mck);
>>> - clk_disable_unprepare(isi->pclk);
>>> }
>>>
>>> static unsigned int isi_camera_poll(struct file *file, poll_table
>>> *pt)
>>> @@ -855,9 +860,14 @@ static int isi_camera_set_bus_param(struct
>>> soc_camera_device *icd)
>>>
>>> cfg1 |= ISI_CFG1_THMASK_BEATS_16;
>>>
>>> + /* Enable PM and peripheral clock before operate isi registers */
>>> + pm_runtime_get_sync(ici->v4l2_dev.dev);
>>> +
>>> isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
>>> isi_writel(isi, ISI_CFG1, cfg1);
>>>
>>> + pm_runtime_put(ici->v4l2_dev.dev);
>>> +
>>> return 0;
>>> }
>>>
>>> @@ -889,6 +899,7 @@ static int atmel_isi_remove(struct platform_device
>>> *pdev) sizeof(struct fbd) * MAX_BUFFER_NUM,
>>> isi->p_fb_descriptors,
>>> isi->fb_descriptors_phys);
>>> + pm_runtime_disable(&pdev->dev);
>>>
>>> return 0;
>>> }
>>> @@ -1027,8 +1038,6 @@ static int atmel_isi_probe(struct platform_device
>>> *pdev) if (isi->pdata.data_width_flags & ISI_DATAWIDTH_10)
>>> isi->width_flags |= 1 << 9;
>>>
>>> - isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
>>> -
>>> irq = platform_get_irq(pdev, 0);
>>> if (IS_ERR_VALUE(irq)) {
>>> ret = irq;
>>> @@ -1049,6 +1058,9 @@ static int atmel_isi_probe(struct platform_device
>>> *pdev) soc_host->v4l2_dev.dev = &pdev->dev;
>>> soc_host->nr = pdev->id;
>>>
>>> + pm_suspend_ignore_children(&pdev->dev, true);
>>> + pm_runtime_enable(&pdev->dev);
>>> +
>>> if (isi->pdata.asd_sizes) {
>>> soc_host->asd = isi->pdata.asd;
>>> soc_host->asd_sizes = isi->pdata.asd_sizes;
>>> @@ -1062,6 +1074,7 @@ static int atmel_isi_probe(struct platform_device
>>> *pdev) return 0;
>>>
>>> err_register_soc_camera_host:
>>> + pm_runtime_disable(&pdev->dev);
>>> err_req_irq:
>>> err_ioremap:
>>> vb2_dma_contig_cleanup_ctx(isi->alloc_ctx);
>>> @@ -1074,6 +1087,30 @@ err_alloc_ctx:
>>> return ret;
>>> }
>>>
>>> +static int atmel_isi_runtime_suspend(struct device *dev)
>>> +{
>>> + struct soc_camera_host *soc_host = to_soc_camera_host(dev);
>>> + struct atmel_isi *isi = container_of(soc_host,
>>> + struct atmel_isi, soc_host);
>>> +
>>> + clk_disable_unprepare(isi->pclk);
>>> +
>>> + return 0;
>>> +}
>>> +static int atmel_isi_runtime_resume(struct device *dev)
>>> +{
>>> + struct soc_camera_host *soc_host = to_soc_camera_host(dev);
>>> + struct atmel_isi *isi = container_of(soc_host,
>>> + struct atmel_isi, soc_host);
>>> +
>>> + return clk_prepare_enable(isi->pclk);
>>> +}
>>> +
>>> +static const struct dev_pm_ops atmel_isi_dev_pm_ops = {
>>> + SET_RUNTIME_PM_OPS(atmel_isi_runtime_suspend,
>>> + atmel_isi_runtime_resume, NULL)
>>> +};
>>> +
>>> static const struct of_device_id atmel_isi_of_match[] = {
>>> { .compatible = "atmel,at91sam9g45-isi" },
>>> { }
>>> @@ -1085,6 +1122,7 @@ static struct platform_driver atmel_isi_driver
>>> = {
>>> .driver = {
>>> .name = "atmel_isi",
>>> .of_match_table = of_match_ptr(atmel_isi_of_match),
>>> + .pm = &atmel_isi_dev_pm_ops,
>>> },
>>> };
>
>
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