[PATCH 01/78] media: atmel: properly get pm_runtime

From: Mauro Carvalho Chehab
Date: Sat Apr 24 2021 - 02:47:50 EST


There are several issues in the way the atmel driver handles
pm_runtime_get_sync():

- it doesn't check return codes;
- it doesn't properly decrement the usage_count on all places;
- it starts streaming even if pm_runtime_get_sync() fails.
- while it tries to get pm_runtime at the clock enable logic,
it doesn't check if the operation was suceeded.

Replace all occurrences of it to use the new kAPI:
pm_runtime_resume_and_get(), which ensures that, if the
return code is not negative, the usage_count was incremented.

With that, add additional checks when this is called, in order
to ensure that errors will be properly addressed.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
drivers/media/platform/atmel/atmel-isc-base.c | 26 ++++++++++++++-----
drivers/media/platform/atmel/atmel-isi.c | 19 +++++++++++---
2 files changed, 34 insertions(+), 11 deletions(-)

diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c
index fe3ec8d0eaee..db1be719192a 100644
--- a/drivers/media/platform/atmel/atmel-isc-base.c
+++ b/drivers/media/platform/atmel/atmel-isc-base.c
@@ -294,9 +294,13 @@ static int isc_wait_clk_stable(struct clk_hw *hw)
static int isc_clk_prepare(struct clk_hw *hw)
{
struct isc_clk *isc_clk = to_isc_clk(hw);
+ int ret;

- if (isc_clk->id == ISC_ISPCK)
- pm_runtime_get_sync(isc_clk->dev);
+ if (isc_clk->id == ISC_ISPCK) {
+ ret = pm_runtime_resume_and_get(isc_clk->dev);
+ if (ret < 0)
+ return 0;
+ }

return isc_wait_clk_stable(hw);
}
@@ -353,9 +357,13 @@ static int isc_clk_is_enabled(struct clk_hw *hw)
{
struct isc_clk *isc_clk = to_isc_clk(hw);
u32 status;
+ int ret;

- if (isc_clk->id == ISC_ISPCK)
- pm_runtime_get_sync(isc_clk->dev);
+ if (isc_clk->id == ISC_ISPCK) {
+ ret = pm_runtime_resume_and_get(isc_clk->dev);
+ if (ret < 0)
+ return 0;
+ }

regmap_read(isc_clk->regmap, ISC_CLKSR, &status);

@@ -807,7 +815,9 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)
goto err_start_stream;
}

- pm_runtime_get_sync(isc->dev);
+ ret = pm_runtime_resume_and_get(isc->dev);
+ if (ret < 0)
+ goto err_pm_get;

ret = isc_configure(isc);
if (unlikely(ret))
@@ -838,7 +848,7 @@ static int isc_start_streaming(struct vb2_queue *vq, unsigned int count)

err_configure:
pm_runtime_put_sync(isc->dev);
-
+err_pm_get:
v4l2_subdev_call(isc->current_subdev->sd, video, s_stream, 0);

err_start_stream:
@@ -1831,7 +1841,9 @@ static void isc_awb_work(struct work_struct *w)
ctrls->hist_id = hist_id;
baysel = isc->config.sd_format->cfa_baycfg << ISC_HIS_CFG_BAYSEL_SHIFT;

- pm_runtime_get_sync(isc->dev);
+ ret = pm_runtime_resume_and_get(isc->dev);
+ if (ret < 0)
+ return;

/*
* only update if we have all the required histograms and controls
diff --git a/drivers/media/platform/atmel/atmel-isi.c b/drivers/media/platform/atmel/atmel-isi.c
index 0514be6153df..6a433926726d 100644
--- a/drivers/media/platform/atmel/atmel-isi.c
+++ b/drivers/media/platform/atmel/atmel-isi.c
@@ -422,7 +422,9 @@ static int start_streaming(struct vb2_queue *vq, unsigned int count)
struct frame_buffer *buf, *node;
int ret;

- pm_runtime_get_sync(isi->dev);
+ ret = pm_runtime_resume_and_get(isi->dev);
+ if (ret < 0)
+ return ret;

/* Enable stream on the sub device */
ret = v4l2_subdev_call(isi->entity.subdev, video, s_stream, 1);
@@ -782,9 +784,10 @@ static int isi_enum_frameintervals(struct file *file, void *fh,
return 0;
}

-static void isi_camera_set_bus_param(struct atmel_isi *isi)
+static int isi_camera_set_bus_param(struct atmel_isi *isi)
{
u32 cfg1 = 0;
+ int ret;

/* set bus param for ISI */
if (isi->pdata.hsync_act_low)
@@ -801,12 +804,16 @@ static void isi_camera_set_bus_param(struct atmel_isi *isi)
cfg1 |= ISI_CFG1_THMASK_BEATS_16;

/* Enable PM and peripheral clock before operate isi registers */
- pm_runtime_get_sync(isi->dev);
+ ret = pm_runtime_resume_and_get(isi->dev);
+ if (ret < 0)
+ return ret;

isi_writel(isi, ISI_CTRL, ISI_CTRL_DIS);
isi_writel(isi, ISI_CFG1, cfg1);

pm_runtime_put(isi->dev);
+
+ return 0;
}

/* -----------------------------------------------------------------------*/
@@ -1085,7 +1092,11 @@ static int isi_graph_notify_complete(struct v4l2_async_notifier *notifier)
dev_err(isi->dev, "No supported mediabus format found\n");
return ret;
}
- isi_camera_set_bus_param(isi);
+ ret = isi_camera_set_bus_param(isi);
+ if (ret) {
+ dev_err(isi->dev, "Can't wake up device\n");
+ return ret;
+ }

ret = isi_set_default_fmt(isi);
if (ret) {
--
2.30.2