media: stm32-dcmi: add power saving support

Implements runtime & system sleep power management ops.

Signed-off-by: Hugues Fruchet <hugues.fruchet@st.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This commit is contained in:
Hugues Fruchet 2018-06-13 05:59:39 -04:00 committed by Mauro Carvalho Chehab
parent f11552d030
commit 152e0bf602
1 changed files with 65 additions and 16 deletions

View File

@ -22,7 +22,9 @@
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_graph.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/videodev2.h>
@ -567,9 +569,9 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
u32 val = 0;
int ret;
ret = clk_enable(dcmi->mclk);
ret = pm_runtime_get_sync(dcmi->dev);
if (ret) {
dev_err(dcmi->dev, "%s: Failed to start streaming, cannot enable clock\n",
dev_err(dcmi->dev, "%s: Failed to start streaming, cannot get sync\n",
__func__);
goto err_release_buffers;
}
@ -579,7 +581,7 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
if (ret && ret != -ENOIOCTLCMD) {
dev_err(dcmi->dev, "%s: Failed to start streaming, subdev streamon error",
__func__);
goto err_disable_clock;
goto err_pm_put;
}
spin_lock_irq(&dcmi->irqlock);
@ -664,8 +666,8 @@ static int dcmi_start_streaming(struct vb2_queue *vq, unsigned int count)
err_subdev_streamoff:
v4l2_subdev_call(dcmi->entity.subdev, video, s_stream, 0);
err_disable_clock:
clk_disable(dcmi->mclk);
err_pm_put:
pm_runtime_put(dcmi->dev);
err_release_buffers:
spin_lock_irq(&dcmi->irqlock);
@ -717,7 +719,7 @@ static void dcmi_stop_streaming(struct vb2_queue *vq)
/* Stop all pending DMA operations */
dmaengine_terminate_all(dcmi->dma_chan);
clk_disable(dcmi->mclk);
pm_runtime_put(dcmi->dev);
if (dcmi->errors_count)
dev_warn(dcmi->dev, "Some errors found while streaming: errors=%d (overrun=%d), buffers=%d\n",
@ -1707,12 +1709,6 @@ static int dcmi_probe(struct platform_device *pdev)
return -EPROBE_DEFER;
}
ret = clk_prepare(mclk);
if (ret) {
dev_err(&pdev->dev, "Unable to prepare mclk %p\n", mclk);
goto err_dma_release;
}
spin_lock_init(&dcmi->irqlock);
mutex_init(&dcmi->lock);
init_completion(&dcmi->complete);
@ -1728,7 +1724,7 @@ static int dcmi_probe(struct platform_device *pdev)
/* Initialize the top-level structure */
ret = v4l2_device_register(&pdev->dev, &dcmi->v4l2_dev);
if (ret)
goto err_clk_unprepare;
goto err_dma_release;
dcmi->vdev = video_device_alloc();
if (!dcmi->vdev) {
@ -1788,14 +1784,15 @@ static int dcmi_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "Probe done\n");
platform_set_drvdata(pdev, dcmi);
pm_runtime_enable(&pdev->dev);
return 0;
err_device_release:
video_device_release(dcmi->vdev);
err_device_unregister:
v4l2_device_unregister(&dcmi->v4l2_dev);
err_clk_unprepare:
clk_unprepare(dcmi->mclk);
err_dma_release:
dma_release_channel(dcmi->dma_chan);
@ -1806,20 +1803,72 @@ static int dcmi_remove(struct platform_device *pdev)
{
struct stm32_dcmi *dcmi = platform_get_drvdata(pdev);
pm_runtime_disable(&pdev->dev);
v4l2_async_notifier_unregister(&dcmi->notifier);
v4l2_device_unregister(&dcmi->v4l2_dev);
clk_unprepare(dcmi->mclk);
dma_release_channel(dcmi->dma_chan);
return 0;
}
static __maybe_unused int dcmi_runtime_suspend(struct device *dev)
{
struct stm32_dcmi *dcmi = dev_get_drvdata(dev);
clk_disable_unprepare(dcmi->mclk);
return 0;
}
static __maybe_unused int dcmi_runtime_resume(struct device *dev)
{
struct stm32_dcmi *dcmi = dev_get_drvdata(dev);
int ret;
ret = clk_prepare_enable(dcmi->mclk);
if (ret)
dev_err(dev, "%s: Failed to prepare_enable clock\n", __func__);
return ret;
}
static __maybe_unused int dcmi_suspend(struct device *dev)
{
/* disable clock */
pm_runtime_force_suspend(dev);
/* change pinctrl state */
pinctrl_pm_select_sleep_state(dev);
return 0;
}
static __maybe_unused int dcmi_resume(struct device *dev)
{
/* restore pinctl default state */
pinctrl_pm_select_default_state(dev);
/* clock enable */
pm_runtime_force_resume(dev);
return 0;
}
static const struct dev_pm_ops dcmi_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(dcmi_suspend, dcmi_resume)
SET_RUNTIME_PM_OPS(dcmi_runtime_suspend,
dcmi_runtime_resume, NULL)
};
static struct platform_driver stm32_dcmi_driver = {
.probe = dcmi_probe,
.remove = dcmi_remove,
.driver = {
.name = DRV_NAME,
.of_match_table = of_match_ptr(stm32_dcmi_of_match),
.pm = &dcmi_pm_ops,
},
};