[PATCH 04/17] media: atomisp: pci: do not use err var when checking port validity for ISP2400

[Tsuchiya Yuto <kitakar@gmail.com>]

Currently, the `port >= N_CSI_PORTS || err` checks for ISP2400 are always
evaluated as true because the err variable is set to `-EINVAL` on
declaration but the variable is never used until the evaluation.

Looking at the diff of commit 3c0538fbad9f ("media: atomisp: get rid of
most checks for ISP2401 version"), the `port >= N_CSI_PORTS` check is
for ISP2400 and the err variable check is for ISP2401. Fix this issue
by adding ISP version test there accordingly.

Yes, there are other better ways to fix this issue, like adding support
for ISP2400 to ia_css_mipi_is_source_port_valid(). In this way, we can
unify the following test:

	if (!IS_ISP2401)
		port = (unsigned int)pipe->stream->config.source.port.port;
	else
		err = ia_css_mipi_is_source_port_valid(pipe, &port);

However, the IS_ISP2401 test here (formerly `ifdef ISP2401`) is not
a result of real hardware difference, but just a result of the following
two different versions of driver merged by tools [1]:

  - ISP2400: irci_stable_candrpv_0415_20150521_0458
  - ISP2401: irci_ecr-master_20150911_0724

We should eventually remove (not unify) such tests caused by just a
driver version difference and use just one version of driver. So, for
now, let's avoid further unification.

[1] The function ia_css_mipi_is_source_port_valid() and its usage is
    added on updating css version to irci_master_20150701_0213
    https://raw.githubusercontent.com/intel/ProductionKernelQuilts/cht-m1stable-2016_ww31/uefi/cht-m1stable/patches/cam-0439-atomisp2-css2401-and-2401_legacy-irci_master_2015070.patch
    ("atomisp2: css2401 and 2401_legacy-irci_master_20150701_0213")

Fixes: 3c0538fbad9f ("media: atomisp: get rid of most checks for ISP2401 version")
Signed-off-by: Tsuchiya Yuto <kitakar@gmail.com>
---
 drivers/staging/media/atomisp/pci/sh_css_mipi.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/media/atomisp/pci/sh_css_mipi.c b/drivers/staging/media/atomisp/pci/sh_css_mipi.c
index 483d40a467c7..65fc93c5d56b 100644
--- a/drivers/staging/media/atomisp/pci/sh_css_mipi.c
+++ b/drivers/staging/media/atomisp/pci/sh_css_mipi.c
@@ -430,7 +430,8 @@ allocate_mipi_frames(struct ia_css_pipe *pipe,
 
 	assert(port < N_CSI_PORTS);
 
-	if (port >= N_CSI_PORTS || err) {
+	if ((!IS_ISP2401 && port >= N_CSI_PORTS) ||
+	    (IS_ISP2401 && err)) {
 		ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
 				    "allocate_mipi_frames(%p) exit: error: port is not correct (port=%d).\n",
 				    pipe, port);
@@ -559,7 +560,8 @@ free_mipi_frames(struct ia_css_pipe *pipe)
 
 		assert(port < N_CSI_PORTS);
 
-		if (port >= N_CSI_PORTS || err) {
+		if ((!IS_ISP2401 && port >= N_CSI_PORTS) ||
+		    (IS_ISP2401 && err)) {
 			ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
 					    "free_mipi_frames(%p, %d) exit: error: pipe port is not correct.\n",
 					    pipe, port);
@@ -670,7 +672,8 @@ send_mipi_frames(struct ia_css_pipe *pipe)
 
 	assert(port < N_CSI_PORTS);
 
-	if (port >= N_CSI_PORTS || err) {
+	if ((!IS_ISP2401 && port >= N_CSI_PORTS) ||
+	    (IS_ISP2401 && err)) {
 		IA_CSS_ERROR("send_mipi_frames(%p) exit: invalid port specified (port=%d).\n",
 			     pipe, port);
 		return err;
-- 
2.33.1