[PATCH v2 1/2] media: atomisp: Fix smatch warnings caused by atomisp custom assert() usage

[Hans de Goede <hdegoede@redhat.com>]

The atomisp code base has a custom assert() macro, a couple of functions
use this in a construction like the following:

   assert(pipe);
   assert(pipe->stream);
   if ((!pipe) || (!pipe->stream)) {
           ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
                               "allocate_mipi_frames(%p) exit: ...\n",
                               pipe);
           return -EINVAL;
   }

The second assert is seen by smatch as dereferencing "pipe" in the above
example (and dereferencing "dvs_6axis_config" in the other case).

Following by the dereferenced variable being checked (a second time)
in the following if () statement.

This triggers the following smatch warnings:
drivers/staging/media/atomisp/pci/sh_css_mipi.c:356 allocate_mipi_frames() warn: variable dereferenced before check 'pipe' (see line 355)
drivers/staging/media/atomisp/pci/sh_css_mipi.c:562 send_mipi_frames() warn: variable dereferenced before check 'pipe' (see line 561)
drivers/staging/media/atomisp/pci/sh_css_param_dvs.c:208 free_dvs_6axis_table() warn: variable dereferenced before check 'dvs_6axis_config' (see line 206)

The custom assert() macro actually expands to a BUG() call and BUG()
calls should not be used in the kernel.

Remove the assert() calls to fix the smatch warnings and in case of
[allocate|send]_mipi_frames() also remove the if () return -EINVAL
block since these functions are never called with a NULL pipe.

Reported-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Note:
1. No Closes: tag since Hans Verkuil reported this in an offlist email.
2. All the other assert() calls really should also be removed.
   I've put this on my todo list.
---
Changes in v2:
- Drop the sh_css_sp.c bits, just dropping the assert() calls is
  not enough there
---
 drivers/staging/media/atomisp/pci/sh_css_mipi.c  | 16 ----------------
 .../staging/media/atomisp/pci/sh_css_param_dvs.c |  3 ---
 2 files changed, 19 deletions(-)

diff --git a/drivers/staging/media/atomisp/pci/sh_css_mipi.c b/drivers/staging/media/atomisp/pci/sh_css_mipi.c
index b20acaab0595..ced21dedf7ac 100644
--- a/drivers/staging/media/atomisp/pci/sh_css_mipi.c
+++ b/drivers/staging/media/atomisp/pci/sh_css_mipi.c
@@ -351,15 +351,6 @@ allocate_mipi_frames(struct ia_css_pipe *pipe,
 	ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
 			    "allocate_mipi_frames(%p) enter:\n", pipe);
 
-	assert(pipe);
-	assert(pipe->stream);
-	if ((!pipe) || (!pipe->stream)) {
-		ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
-				    "allocate_mipi_frames(%p) exit: pipe or stream is null.\n",
-				    pipe);
-		return -EINVAL;
-	}
-
 	if (IS_ISP2401 && pipe->stream->config.online) {
 		ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
 				    "allocate_mipi_frames(%p) exit: no buffers needed for 2401 pipe mode.\n",
@@ -557,13 +548,6 @@ send_mipi_frames(struct ia_css_pipe *pipe)
 
 	IA_CSS_ENTER_PRIVATE("pipe=%p", pipe);
 
-	assert(pipe);
-	assert(pipe->stream);
-	if (!pipe || !pipe->stream) {
-		IA_CSS_ERROR("pipe or stream is null");
-		return -EINVAL;
-	}
-
 	/* multi stream video needs mipi buffers */
 	/* nothing to be done in other cases. */
 	if (pipe->stream->config.mode != IA_CSS_INPUT_MODE_BUFFERED_SENSOR) {
diff --git a/drivers/staging/media/atomisp/pci/sh_css_param_dvs.c b/drivers/staging/media/atomisp/pci/sh_css_param_dvs.c
index ff0082d02af3..5174bc210ae1 100644
--- a/drivers/staging/media/atomisp/pci/sh_css_param_dvs.c
+++ b/drivers/staging/media/atomisp/pci/sh_css_param_dvs.c
@@ -202,9 +202,6 @@ generate_dvs_6axis_table_from_config(struct ia_css_dvs_6axis_config
 void
 free_dvs_6axis_table(struct ia_css_dvs_6axis_config  **dvs_6axis_config)
 {
-	assert(dvs_6axis_config);
-	assert(*dvs_6axis_config);
-
 	if ((dvs_6axis_config) && (*dvs_6axis_config)) {
 		IA_CSS_ENTER_PRIVATE("dvs_6axis_config %p", (*dvs_6axis_config));
 		if ((*dvs_6axis_config)->xcoords_y) {
-- 
2.41.0