Skip to content

Commit

Permalink
drm/modes: Rewrite the command line parser
Browse files Browse the repository at this point in the history 
Rewrite the command line parser in order to get away from the state machine
parsing the video mode lines.

Hopefully, this will allow to extend it more easily to support named modes
and / or properties set directly on the command line.

Reviewed-by: Noralf Trønnes <noralf@tronnes.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Link: https://patchwork.freedesktop.org/patch/msgid/e32cd4009153b184103554009135c7bf7c9975d7.1560783090.git-series.maxime.ripard@bootlin.com
  • Loading branch information
@mripard
mripard committed Jun 19, 2019
1 parent a99076e commit e08ab74
Showing 1 changed file with 210 additions and 115 deletions.
325 changes: 210 additions & 115 deletions drivers/gpu/drm/drm_modes.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -30,6 +30,7 @@
* authorization from the copyright holder(s) and author(s).
*/

#include <linux/ctype.h>
#include <linux/list.h>
#include <linux/list_sort.h>
#include <linux/export.h>
Expand Down Expand Up @@ -1408,6 +1409,151 @@ void drm_connector_list_update(struct drm_connector *connector)
}
EXPORT_SYMBOL(drm_connector_list_update);

static int drm_mode_parse_cmdline_bpp(const char *str, char **end_ptr,
struct drm_cmdline_mode *mode)
{
unsigned int bpp;

if (str[0] != '-')
return -EINVAL;

str++;
bpp = simple_strtol(str, end_ptr, 10);
if (*end_ptr == str)
return -EINVAL;

mode->bpp = bpp;
mode->bpp_specified = true;

return 0;
}

static int drm_mode_parse_cmdline_refresh(const char *str, char **end_ptr,
struct drm_cmdline_mode *mode)
{
unsigned int refresh;

if (str[0] != '@')
return -EINVAL;

str++;
refresh = simple_strtol(str, end_ptr, 10);
if (*end_ptr == str)
return -EINVAL;

mode->refresh = refresh;
mode->refresh_specified = true;

return 0;
}

static int drm_mode_parse_cmdline_extra(const char *str, int length,
struct drm_connector *connector,
struct drm_cmdline_mode *mode)
{
int i;

for (i = 0; i < length; i++) {
switch (str[i]) {
case 'i':
mode->interlace = true;
break;
case 'm':
mode->margins = true;
break;
case 'D':
if (mode->force != DRM_FORCE_UNSPECIFIED)
return -EINVAL;

if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
(connector->connector_type != DRM_MODE_CONNECTOR_HDMIB))
mode->force = DRM_FORCE_ON;
else
mode->force = DRM_FORCE_ON_DIGITAL;
break;
case 'd':
if (mode->force != DRM_FORCE_UNSPECIFIED)
return -EINVAL;

mode->force = DRM_FORCE_OFF;
break;
case 'e':
if (mode->force != DRM_FORCE_UNSPECIFIED)
return -EINVAL;

mode->force = DRM_FORCE_ON;
break;
default:
return -EINVAL;
}
}

return 0;
}

static int drm_mode_parse_cmdline_res_mode(const char *str, unsigned int length,
bool extras,
struct drm_connector *connector,
struct drm_cmdline_mode *mode)
{
const char *str_start = str;
bool rb = false, cvt = false;
int xres = 0, yres = 0;
int remaining, i;
char *end_ptr;

xres = simple_strtol(str, &end_ptr, 10);
if (end_ptr == str)
return -EINVAL;

if (end_ptr[0] != 'x')
return -EINVAL;
end_ptr++;

str = end_ptr;
yres = simple_strtol(str, &end_ptr, 10);
if (end_ptr == str)
return -EINVAL;

remaining = length - (end_ptr - str_start);
if (remaining < 0)
return -EINVAL;

for (i = 0; i < remaining; i++) {
switch (end_ptr[i]) {
case 'M':
cvt = true;
break;
case 'R':
rb = true;
break;
default:
/*
* Try to pass that to our extras parsing
* function to handle the case where the
* extras are directly after the resolution
*/
if (extras) {
int ret = drm_mode_parse_cmdline_extra(end_ptr + i,
1,
connector,
mode);
if (ret)
return ret;
} else {
return -EINVAL;
}
}
}

mode->xres = xres;
mode->yres = yres;
mode->cvt = cvt;
mode->rb = rb;

return 0;
}

/**
* drm_mode_parse_command_line_for_connector - parse command line modeline for connector
* @mode_option: optional per connector mode option
Expand All @@ -1434,13 +1580,12 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
struct drm_cmdline_mode *mode)
{
const char *name;
unsigned int namelen;
bool res_specified = false, bpp_specified = false, refresh_specified = false;
unsigned int xres = 0, yres = 0, bpp = 32, refresh = 0;
bool yres_specified = false, cvt = false, rb = false;
bool interlace = false, margins = false, was_digit = false;
int i;
enum drm_connector_force force = DRM_FORCE_UNSPECIFIED;
bool parse_extras = false;
unsigned int bpp_off = 0, refresh_off = 0;
unsigned int mode_end = 0;
char *bpp_ptr = NULL, *refresh_ptr = NULL, *extra_ptr = NULL;
char *bpp_end_ptr = NULL, *refresh_end_ptr = NULL;
int ret;

#ifdef CONFIG_FB
if (!mode_option)
Expand All @@ -1453,127 +1598,77 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
}

name = mode_option;
namelen = strlen(name);
for (i = namelen-1; i >= 0; i--) {
switch (name[i]) {
case '@':
if (!refresh_specified && !bpp_specified &&
!yres_specified && !cvt && !rb && was_digit) {
refresh = simple_strtol(&name[i+1], NULL, 10);
refresh_specified = true;
was_digit = false;
} else
goto done;
break;
case '-':
if (!bpp_specified && !yres_specified && !cvt &&
!rb && was_digit) {
bpp = simple_strtol(&name[i+1], NULL, 10);
bpp_specified = true;
was_digit = false;
} else
goto done;
break;
case 'x':
if (!yres_specified && was_digit) {
yres = simple_strtol(&name[i+1], NULL, 10);
yres_specified = true;
was_digit = false;
} else
goto done;
break;
case '0' ... '9':
was_digit = true;
break;
case 'M':
if (yres_specified || cvt || was_digit)
goto done;
cvt = true;
break;
case 'R':
if (yres_specified || cvt || rb || was_digit)
goto done;
rb = true;
break;
case 'm':
if (cvt || yres_specified || was_digit)
goto done;
margins = true;
break;
case 'i':
if (cvt || yres_specified || was_digit)
goto done;
interlace = true;
break;
case 'e':
if (yres_specified || bpp_specified || refresh_specified ||
was_digit || (force != DRM_FORCE_UNSPECIFIED))
goto done;

force = DRM_FORCE_ON;
break;
case 'D':
if (yres_specified || bpp_specified || refresh_specified ||
was_digit || (force != DRM_FORCE_UNSPECIFIED))
goto done;
if (!isdigit(name[0]))
return false;

if ((connector->connector_type != DRM_MODE_CONNECTOR_DVII) &&
(connector->connector_type != DRM_MODE_CONNECTOR_HDMIB))
force = DRM_FORCE_ON;
else
force = DRM_FORCE_ON_DIGITAL;
break;
case 'd':
if (yres_specified || bpp_specified || refresh_specified ||
was_digit || (force != DRM_FORCE_UNSPECIFIED))
goto done;
/* Try to locate the bpp and refresh specifiers, if any */
bpp_ptr = strchr(name, '-');
if (bpp_ptr) {
bpp_off = bpp_ptr - name;
mode->bpp_specified = true;
}

force = DRM_FORCE_OFF;
break;
default:
goto done;
}
refresh_ptr = strchr(name, '@');
if (refresh_ptr) {
refresh_off = refresh_ptr - name;
mode->refresh_specified = true;
}

if (i < 0 && yres_specified) {
char *ch;
xres = simple_strtol(name, &ch, 10);
if ((ch != NULL) && (*ch == 'x'))
res_specified = true;
else
i = ch - name;
} else if (!yres_specified && was_digit) {
/* catch mode that begins with digits but has no 'x' */
i = 0;
/* Locate the end of the name / resolution, and parse it */
if (bpp_ptr && refresh_ptr) {
mode_end = min(bpp_off, refresh_off);
} else if (bpp_ptr) {
mode_end = bpp_off;
} else if (refresh_ptr) {
mode_end = refresh_off;
} else {
mode_end = strlen(name);
parse_extras = true;
}
done:
if (i >= 0) {
pr_warn("[drm] parse error at position %i in video mode '%s'\n",
i, name);
mode->specified = false;

ret = drm_mode_parse_cmdline_res_mode(name, mode_end,
parse_extras,
connector,
mode);
if (ret)
return false;
}
mode->specified = true;

if (res_specified) {
mode->specified = true;
mode->xres = xres;
mode->yres = yres;
if (bpp_ptr) {
ret = drm_mode_parse_cmdline_bpp(bpp_ptr, &bpp_end_ptr, mode);
if (ret)
return false;
}

if (refresh_specified) {
mode->refresh_specified = true;
mode->refresh = refresh;
if (refresh_ptr) {
ret = drm_mode_parse_cmdline_refresh(refresh_ptr,
&refresh_end_ptr, mode);
if (ret)
return false;
}

if (bpp_specified) {
mode->bpp_specified = true;
mode->bpp = bpp;
/*
* Locate the end of the bpp / refresh, and parse the extras
* if relevant
*/
if (bpp_ptr && refresh_ptr)
extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
else if (bpp_ptr)
extra_ptr = bpp_end_ptr;
else if (refresh_ptr)
extra_ptr = refresh_end_ptr;

if (extra_ptr) {
int remaining = strlen(name) - (extra_ptr - name);

/*
* We still have characters to process, while
* we shouldn't have any
*/
if (remaining > 0)
return false;
}
mode->rb = rb;
mode->cvt = cvt;
mode->interlace = interlace;
mode->margins = margins;
mode->force = force;

return true;
}
Expand Down

0 comments on commit e08ab74

Please sign in to comment.