* [PATCH v7] staging: xgifb: correct the multiple line dereference
@ 2017-02-28 10:45 Arushi Singhal
2017-02-28 11:11 ` Joe Perches
0 siblings, 1 reply; 4+ messages in thread
From: Arushi Singhal @ 2017-02-28 10:45 UTC (permalink / raw)
To: arnaud.patard; +Cc: Greg Kroah-Hartman, devel, linux-kernel, outreachy-kernel
Error reported by checkpatch.pl as "avoid multiple line dereference".
Addition of new variables to make the code more readable.
Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
---
changes in v7
- Improve the coding style.
- Introduced new variables.
drivers/staging/xgifb/XGI_main_26.c | 29 ++++++-----------------------
drivers/staging/xgifb/vb_setmode.c | 11 +++++------
2 files changed, 11 insertions(+), 29 deletions(-)
diff --git a/drivers/staging/xgifb/XGI_main_26.c b/drivers/staging/xgifb/XGI_main_26.c
index 69ed137337ce..9870ea3b76b4 100644
--- a/drivers/staging/xgifb/XGI_main_26.c
+++ b/drivers/staging/xgifb/XGI_main_26.c
@@ -878,30 +878,13 @@ static void XGIfb_post_setmode(struct xgifb_video_info *xgifb_info)
}
if ((filter >= 0) && (filter <= 7)) {
+ const u8 *f = XGI_TV_filter[filter_tb].filter[filter];
pr_debug("FilterTable[%d]-%d: %*ph\n",
- filter_tb, filter,
- 4, XGI_TV_filter[filter_tb].
- filter[filter]);
- xgifb_reg_set(
- XGIPART2,
- 0x35,
- (XGI_TV_filter[filter_tb].
- filter[filter][0]));
- xgifb_reg_set(
- XGIPART2,
- 0x36,
- (XGI_TV_filter[filter_tb].
- filter[filter][1]));
- xgifb_reg_set(
- XGIPART2,
- 0x37,
- (XGI_TV_filter[filter_tb].
- filter[filter][2]));
- xgifb_reg_set(
- XGIPART2,
- 0x38,
- (XGI_TV_filter[filter_tb].
- filter[filter][3]));
+ filter_tb, filter, 4, f);
+ xgifb_reg_set(XGIPART2, 0x35, f[0]);
+ xgifb_reg_set(XGIPART2, 0x36, f[1]);
+ xgifb_reg_set(XGIPART2, 0x37, f[2]);
+ xgifb_reg_set(XGIPART2, 0x38, f[3]);
}
}
}
diff --git a/drivers/staging/xgifb/vb_setmode.c b/drivers/staging/xgifb/vb_setmode.c
index 7c7c8c8f1df3..ab84adbc542d 100644
--- a/drivers/staging/xgifb/vb_setmode.c
+++ b/drivers/staging/xgifb/vb_setmode.c
@@ -221,8 +221,8 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
for (; XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID ==
tempbx; (*i)--) {
- infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].
- Ext_InfoFlag;
+ infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].Ext_InfoFlag;
+
if (infoflag & tempax)
return 1;
@@ -231,8 +231,8 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
}
for ((*i) = 0;; (*i)++) {
- infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].
- Ext_InfoFlag;
+ infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].Ext_InfoFlag;
+
if (XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID
!= tempbx) {
return 0;
@@ -5092,8 +5092,7 @@ unsigned short XGI_GetRatePtrCRT2(struct xgi_hw_device_info *pXGIHWDE,
i = 0;
do {
- if (XGI330_RefIndex[RefreshRateTableIndex + i].
- ModeID != ModeNo)
+ if (XGI330_RefIndex[RefreshRateTableIndex + i].ModeID != ModeNo)
break;
temp = XGI330_RefIndex[RefreshRateTableIndex + i].Ext_InfoFlag;
temp &= ModeTypeMask;
--
2.11.0
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v7] staging: xgifb: correct the multiple line dereference
2017-02-28 10:45 [PATCH v7] staging: xgifb: correct the multiple line dereference Arushi Singhal
@ 2017-02-28 11:11 ` Joe Perches
2017-02-28 11:24 ` [Outreachy kernel] " Julia Lawall
0 siblings, 1 reply; 4+ messages in thread
From: Joe Perches @ 2017-02-28 11:11 UTC (permalink / raw)
To: Arushi Singhal, arnaud.patard
Cc: Greg Kroah-Hartman, devel, linux-kernel, outreachy-kernel
On Tue, 2017-02-28 at 16:15 +0530, Arushi Singhal wrote:
> Error reported by checkpatch.pl as "avoid multiple line dereference".
> Addition of new variables to make the code more readable.
You should probably split this into 2 patches, one for
each file.
What Julia said about finding a better/shorter identifier
than RefreshRateTableIndex is true but I still suggest
something like:
> diff --git a/drivers/staging/xgifb/vb_setmode.c b/drivers/staging/xgifb/vb_setmode.c@@ -221,8 +221,8 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
>
> for (; XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID ==
> tempbx; (*i)--) {
> - infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].
> - Ext_InfoFlag;
> + infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].Ext_InfoFlag;
> +
I suggest something like:
---
drivers/staging/xgifb/vb_setmode.c | 41 ++++++++++++++++++--------------------
1 file changed, 19 insertions(+), 22 deletions(-)
diff --git a/drivers/staging/xgifb/vb_setmode.c b/drivers/staging/xgifb/vb_setmode.c
index 7c7c8c8f1df3..daa3318aab41 100644
--- a/drivers/staging/xgifb/vb_setmode.c
+++ b/drivers/staging/xgifb/vb_setmode.c
@@ -172,10 +172,12 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
struct vb_device_info *pVBInfo)
{
unsigned short tempax, tempbx, resinfo, modeflag, infoflag;
+ const struct XGI_Ext2Struct *ext2;
modeflag = XGI330_EModeIDTable[ModeIdIndex].Ext_ModeFlag;
resinfo = XGI330_EModeIDTable[ModeIdIndex].Ext_RESINFO;
- tempbx = XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID;
+ ext2 = &XGI330_RefIndex[RefreshRateTableIndex];
+ tempbx = ext2[*i].ModeID;
tempax = 0;
if (pVBInfo->VBInfo & SetCRT2ToRAMDAC) {
@@ -219,10 +221,8 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
return 0;
}
- for (; XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID ==
- tempbx; (*i)--) {
- infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].
- Ext_InfoFlag;
+ for (; ext2[*i].ModeID == tempbx; (*i)--) {
+ infoflag = ext2[*i].Ext_InfoFlag;
if (infoflag & tempax)
return 1;
@@ -231,12 +231,9 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
}
for ((*i) = 0;; (*i)++) {
- infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].
- Ext_InfoFlag;
- if (XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID
- != tempbx) {
+ infoflag = ext2[*i].Ext_InfoFlag;
+ if (ext2[*i].ModeID != tempbx)
return 0;
- }
if (infoflag & tempax)
return 1;
@@ -5050,6 +5047,7 @@ unsigned short XGI_GetRatePtrCRT2(struct xgi_hw_device_info *pXGIHWDE,
{
const u8 LCDARefreshIndex[] = {
0x00, 0x00, 0x03, 0x01, 0x01, 0x01, 0x01, 0x00 };
+ const struct XGI_Ext2Struct *ext2;
unsigned short RefreshRateTableIndex, i, index, temp;
@@ -5073,29 +5071,29 @@ unsigned short XGI_GetRatePtrCRT2(struct xgi_hw_device_info *pXGIHWDE,
}
RefreshRateTableIndex = XGI330_EModeIDTable[ModeIdIndex].REFindex;
- ModeNo = XGI330_RefIndex[RefreshRateTableIndex].ModeID;
+ ext2 = &XGI330_RefIndex[RefreshRateTableIndex];
+ ModeNo = ext2->ModeID;
if (pXGIHWDE->jChipType >= XG20) { /* for XG20, XG21, XG27 */
- if ((XGI330_RefIndex[RefreshRateTableIndex].XRes == 800) &&
- (XGI330_RefIndex[RefreshRateTableIndex].YRes == 600)) {
+ if ((ext2->XRes == 800) &&
+ (ext2->YRes == 600)) {
index++;
}
/* do the similar adjustment like XGISearchCRT1Rate() */
- if ((XGI330_RefIndex[RefreshRateTableIndex].XRes == 1024) &&
- (XGI330_RefIndex[RefreshRateTableIndex].YRes == 768)) {
+ if ((ext2->XRes == 1024) &&
+ (ext2->YRes == 768)) {
index++;
}
- if ((XGI330_RefIndex[RefreshRateTableIndex].XRes == 1280) &&
- (XGI330_RefIndex[RefreshRateTableIndex].YRes == 1024)) {
+ if ((ext2->XRes == 1280) &&
+ (ext2->YRes == 1024)) {
index++;
}
}
i = 0;
do {
- if (XGI330_RefIndex[RefreshRateTableIndex + i].
- ModeID != ModeNo)
+ if (ext2[i].ModeID != ModeNo)
break;
- temp = XGI330_RefIndex[RefreshRateTableIndex + i].Ext_InfoFlag;
+ temp = ext2[i].Ext_InfoFlag;
temp &= ModeTypeMask;
if (temp < pVBInfo->ModeType)
break;
@@ -5105,8 +5103,7 @@ unsigned short XGI_GetRatePtrCRT2(struct xgi_hw_device_info *pXGIHWDE,
} while (index != 0xFFFF);
if (!(pVBInfo->VBInfo & SetCRT2ToRAMDAC)) {
if (pVBInfo->VBInfo & SetInSlaveMode) {
- temp = XGI330_RefIndex[RefreshRateTableIndex + i - 1].
- Ext_InfoFlag;
+ temp = ext2[i - 1].Ext_InfoFlag;
if (temp & InterlaceMode)
i++;
}
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [Outreachy kernel] Re: [PATCH v7] staging: xgifb: correct the multiple line dereference
2017-02-28 11:11 ` Joe Perches
@ 2017-02-28 11:24 ` Julia Lawall
2017-02-28 11:29 ` Joe Perches
0 siblings, 1 reply; 4+ messages in thread
From: Julia Lawall @ 2017-02-28 11:24 UTC (permalink / raw)
To: Joe Perches
Cc: Arushi Singhal, arnaud.patard, Greg Kroah-Hartman, devel,
linux-kernel, outreachy-kernel
On Tue, 28 Feb 2017, Joe Perches wrote:
> On Tue, 2017-02-28 at 16:15 +0530, Arushi Singhal wrote:
> > Error reported by checkpatch.pl as "avoid multiple line dereference".
> > Addition of new variables to make the code more readable.
>
> You should probably split this into 2 patches, one for
> each file.
>
> What Julia said about finding a better/shorter identifier
> than RefreshRateTableIndex is true but I still suggest
> something like:
>
> > diff --git a/drivers/staging/xgifb/vb_setmode.c b/drivers/staging/xgifb/vb_setmode.c@@ -221,8 +221,8 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
> >
> > for (; XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID ==
> > tempbx; (*i)--) {
> > - infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].
> > - Ext_InfoFlag;
> > + infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].Ext_InfoFlag;
> > +
>
> I suggest something like:
> ---
> drivers/staging/xgifb/vb_setmode.c | 41 ++++++++++++++++++--------------------
> 1 file changed, 19 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/staging/xgifb/vb_setmode.c b/drivers/staging/xgifb/vb_setmode.c
> index 7c7c8c8f1df3..daa3318aab41 100644
> --- a/drivers/staging/xgifb/vb_setmode.c
> +++ b/drivers/staging/xgifb/vb_setmode.c
> @@ -172,10 +172,12 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
> struct vb_device_info *pVBInfo)
> {
> unsigned short tempax, tempbx, resinfo, modeflag, infoflag;
> + const struct XGI_Ext2Struct *ext2;
>
> modeflag = XGI330_EModeIDTable[ModeIdIndex].Ext_ModeFlag;
> resinfo = XGI330_EModeIDTable[ModeIdIndex].Ext_RESINFO;
> - tempbx = XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID;
> + ext2 = &XGI330_RefIndex[RefreshRateTableIndex];
> + tempbx = ext2[*i].ModeID;
> tempax = 0;
>
> if (pVBInfo->VBInfo & SetCRT2ToRAMDAC) {
> @@ -219,10 +221,8 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
> return 0;
> }
>
> - for (; XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID ==
> - tempbx; (*i)--) {
> - infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].
> - Ext_InfoFlag;
> + for (; ext2[*i].ModeID == tempbx; (*i)--) {
> + infoflag = ext2[*i].Ext_InfoFlag;
> if (infoflag & tempax)
> return 1;
>
> @@ -231,12 +231,9 @@ static unsigned char XGI_AjustCRT2Rate(unsigned short ModeIdIndex,
> }
>
> for ((*i) = 0;; (*i)++) {
> - infoflag = XGI330_RefIndex[RefreshRateTableIndex + (*i)].
> - Ext_InfoFlag;
> - if (XGI330_RefIndex[RefreshRateTableIndex + (*i)].ModeID
> - != tempbx) {
> + infoflag = ext2[*i].Ext_InfoFlag;
> + if (ext2[*i].ModeID != tempbx)
> return 0;
> - }
It's drifting a little bit from the original issue, but the whole *i thing
is not very nice. The function is used in only one place, and the call
looks like this:
temp = XGI_AjustCRT2Rate(ModeIdIndex, RefreshRateTableIndex,
&i, pVBInfo);
immediately followed by:
return RefreshRateTableIndex + i;
temp is never used. Could the function be made to return a negative error
code on failure and the updated value of i on success? The (*i) could
become just i, which would even be a little shorter.
julia
>
> if (infoflag & tempax)
> return 1;
> @@ -5050,6 +5047,7 @@ unsigned short XGI_GetRatePtrCRT2(struct xgi_hw_device_info *pXGIHWDE,
> {
> const u8 LCDARefreshIndex[] = {
> 0x00, 0x00, 0x03, 0x01, 0x01, 0x01, 0x01, 0x00 };
> + const struct XGI_Ext2Struct *ext2;
>
> unsigned short RefreshRateTableIndex, i, index, temp;
>
> @@ -5073,29 +5071,29 @@ unsigned short XGI_GetRatePtrCRT2(struct xgi_hw_device_info *pXGIHWDE,
> }
>
> RefreshRateTableIndex = XGI330_EModeIDTable[ModeIdIndex].REFindex;
> - ModeNo = XGI330_RefIndex[RefreshRateTableIndex].ModeID;
> + ext2 = &XGI330_RefIndex[RefreshRateTableIndex];
> + ModeNo = ext2->ModeID;
> if (pXGIHWDE->jChipType >= XG20) { /* for XG20, XG21, XG27 */
> - if ((XGI330_RefIndex[RefreshRateTableIndex].XRes == 800) &&
> - (XGI330_RefIndex[RefreshRateTableIndex].YRes == 600)) {
> + if ((ext2->XRes == 800) &&
> + (ext2->YRes == 600)) {
> index++;
> }
> /* do the similar adjustment like XGISearchCRT1Rate() */
> - if ((XGI330_RefIndex[RefreshRateTableIndex].XRes == 1024) &&
> - (XGI330_RefIndex[RefreshRateTableIndex].YRes == 768)) {
> + if ((ext2->XRes == 1024) &&
> + (ext2->YRes == 768)) {
> index++;
> }
> - if ((XGI330_RefIndex[RefreshRateTableIndex].XRes == 1280) &&
> - (XGI330_RefIndex[RefreshRateTableIndex].YRes == 1024)) {
> + if ((ext2->XRes == 1280) &&
> + (ext2->YRes == 1024)) {
> index++;
> }
> }
>
> i = 0;
> do {
> - if (XGI330_RefIndex[RefreshRateTableIndex + i].
> - ModeID != ModeNo)
> + if (ext2[i].ModeID != ModeNo)
> break;
> - temp = XGI330_RefIndex[RefreshRateTableIndex + i].Ext_InfoFlag;
> + temp = ext2[i].Ext_InfoFlag;
> temp &= ModeTypeMask;
> if (temp < pVBInfo->ModeType)
> break;
> @@ -5105,8 +5103,7 @@ unsigned short XGI_GetRatePtrCRT2(struct xgi_hw_device_info *pXGIHWDE,
> } while (index != 0xFFFF);
> if (!(pVBInfo->VBInfo & SetCRT2ToRAMDAC)) {
> if (pVBInfo->VBInfo & SetInSlaveMode) {
> - temp = XGI330_RefIndex[RefreshRateTableIndex + i - 1].
> - Ext_InfoFlag;
> + temp = ext2[i - 1].Ext_InfoFlag;
> if (temp & InterlaceMode)
> i++;
> }
>
> --
> You received this message because you are subscribed to the Google Groups "outreachy-kernel" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to outreachy-kernel+unsubscribe@googlegroups.com.
> To post to this group, send email to outreachy-kernel@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/outreachy-kernel/1488280264.25838.26.camel%40perches.com.
> For more options, visit https://groups.google.com/d/optout.
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [Outreachy kernel] Re: [PATCH v7] staging: xgifb: correct the multiple line dereference
2017-02-28 11:24 ` [Outreachy kernel] " Julia Lawall
@ 2017-02-28 11:29 ` Joe Perches
0 siblings, 0 replies; 4+ messages in thread
From: Joe Perches @ 2017-02-28 11:29 UTC (permalink / raw)
To: Julia Lawall
Cc: Arushi Singhal, arnaud.patard, Greg Kroah-Hartman, devel,
linux-kernel, outreachy-kernel
On Tue, 2017-02-28 at 12:24 +0100, Julia Lawall wrote:
> It's drifting a little bit from the original issue, but the whole *i thing
> is not very nice. The function is used in only one place, and the call
> looks like this:
>
> temp = XGI_AjustCRT2Rate(ModeIdIndex, RefreshRateTableIndex,
> &i, pVBInfo);
>
> immediately followed by:
>
> return RefreshRateTableIndex + i;
>
> temp is never used. Could the function be made to return a negative error
> code on failure and the updated value of i on success? The (*i) could
> become just i, which would even be a little shorter.
I don't see why not.
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2017-02-28 14:09 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-02-28 10:45 [PATCH v7] staging: xgifb: correct the multiple line dereference Arushi Singhal
2017-02-28 11:11 ` Joe Perches
2017-02-28 11:24 ` [Outreachy kernel] " Julia Lawall
2017-02-28 11:29 ` Joe Perches
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).