[PATCH v2] media: atomisp: Add lock asserts for mutex protection

Abdelrahman Fekry
2025-08-15T18:24:48Z

Add lockdep_assert_held(&isp->mutex) to critical functions accessing
shared device state. This enforces proper locking and detects violations.

Suggested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Abdelrahman Fekry <abdelrahmanfekry375@gmail.com>

---
v2:
- Fix Typos
- tested by building the driver

v1: https://lore.kernel.org/all/20250815170901.32105-1-abdelrahmanfekry375@gmail.com/
.../staging/media/atomisp/pci/atomisp_cmd.c | 3 ++
.../media/atomisp/pci/atomisp_compat_css20.c | 31 +++++++++++++++++++
2 files changed, 34 insertions(+)

diff --git a/drivers/staging/media/atomisp/pci/atomisp_cmd.c b/drivers/staging/media/atomisp/pci/atomisp_cmd.c
index 3a4eb4f6d3be..48ca33e1c92d 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_cmd.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_cmd.c
@@ -3794,6 +3794,7 @@ int atomisp_try_fmt(struct atomisp_device *isp, struct v4l2_pix_format *f,
const struct atomisp_format_bridge **fmt_ret,
const struct atomisp_format_bridge **snr_fmt_ret)
{
+ lockdep_assert_held(&isp->mutex);
const struct atomisp_format_bridge *fmt, *snr_fmt;
struct atomisp_sub_device *asd = &isp->asd;
struct v4l2_mbus_framefmt ffmt = { };
@@ -4324,6 +4325,8 @@ static int atomisp_set_fmt_to_snr(struct video_device *vdev, const struct v4l2_p
int atomisp_set_fmt(struct video_device *vdev, struct v4l2_format *f)
{
struct atomisp_device *isp = video_get_drvdata(vdev);
+ lockdep_assert_held(&isp->mutex);
+
struct atomisp_video_pipe *pipe = atomisp_to_video_pipe(vdev);
struct atomisp_sub_device *asd = pipe->asd;
const struct atomisp_format_bridge *format_bridge;
diff --git a/drivers/staging/media/atomisp/pci/atomisp_compat_css20.c b/drivers/staging/media/atomisp/pci/atomisp_compat_css20.c
index be5f37f4a6fd..94f63d6a85df 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_compat_css20.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_compat_css20.c
@@ -1447,6 +1447,9 @@ int atomisp_css_input_set_resolution(struct atomisp_sub_device *asd,
enum atomisp_input_stream_id stream_id,
struct v4l2_mbus_framefmt *ffmt)
{
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
struct ia_css_stream_config *s_config =
&asd->stream_env[stream_id].stream_config;

@@ -1519,6 +1522,10 @@ int atomisp_css_set_default_isys_config(struct atomisp_sub_device *asd,
enum atomisp_input_stream_id stream_id,
struct v4l2_mbus_framefmt *ffmt)
{
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
+
int i;
struct ia_css_stream_config *s_config =
&asd->stream_env[stream_id].stream_config;
@@ -1621,6 +1628,9 @@ void atomisp_css_input_set_two_pixels_per_clock(

void atomisp_css_enable_dz(struct atomisp_sub_device *asd, bool enable)
{
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
int i;

for (i = 0; i < IA_CSS_PIPE_ID_NUM; i++)
@@ -1631,6 +1641,9 @@ void atomisp_css_enable_dz(struct atomisp_sub_device *asd, bool enable)
void atomisp_css_capture_set_mode(struct atomisp_sub_device *asd,
enum ia_css_capture_mode mode)
{
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
struct atomisp_stream_env *stream_env =
&asd->stream_env[ATOMISP_INPUT_STREAM_GENERAL];

@@ -1646,6 +1659,9 @@ void atomisp_css_capture_set_mode(struct atomisp_sub_device *asd,
void atomisp_css_input_set_mode(struct atomisp_sub_device *asd,
enum ia_css_input_mode mode)
{
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
unsigned int size_mem_words;
int i;

@@ -1690,6 +1706,10 @@ void atomisp_css_input_set_mode(struct atomisp_sub_device *asd,
void atomisp_css_capture_enable_online(struct atomisp_sub_device *asd,
unsigned short stream_index, bool enable)
{
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
+
struct atomisp_stream_env *stream_env =
&asd->stream_env[stream_index];

@@ -1726,6 +1746,10 @@ int atomisp_css_input_configure_port(
{
int i;
struct atomisp_stream_env *stream_env;
+
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
/*
* Calculate rx_count as follows:
* Input: mipi_freq : CSI-2 bus frequency in Hz
@@ -1760,6 +1784,10 @@ int atomisp_css_input_configure_port(

void atomisp_css_stop(struct atomisp_sub_device *asd, bool in_reset)
{
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
+
unsigned long irqflags;
unsigned int i;

@@ -1815,6 +1843,9 @@ void atomisp_css_continuous_set_num_raw_frames(
struct atomisp_sub_device *asd,
int num_frames)
{
+ struct atomisp_device *isp = asd->isp;
+
+ lockdep_assert_held(&isp->mutex);
if (asd->enable_raw_buffer_lock->val) {
asd->stream_env[ATOMISP_INPUT_STREAM_GENERAL]
.stream_config.init_num_cont_raw_buf =
--
2.25.1