[PATCH v2 3/5] drm/modes: Allow to specify rotation and reflection on the commandline

Maxime Ripard
2019-04-11T13:23:28Z

Rotations and reflections setup are needed in some scenarios to initialise
properly the initial framebuffer. Some drivers already had a bunch of
quirks to deal with this, such as either a private kernel command line
parameter (omapdss) or on the device tree (various panels).

In order to accomodate this, let's create a video mode parameter to deal
with the rotation and reflexion.

Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
---
drivers/gpu/drm/drm_fb_helper.c | 4 +-
drivers/gpu/drm/drm_modes.c | 110 +++++++++++++++++++++++++++------
include/drm/drm_connector.h | 1 +-
3 files changed, 95 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index b3a5d79436ae..8781897559b2 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -2521,6 +2521,7 @@ static void drm_setup_crtc_rotation(struct drm_fb_helper *fb_helper,
struct drm_connector *connector)
{
struct drm_plane *plane = fb_crtc->mode_set.crtc->primary;
+ struct drm_cmdline_mode *mode = &connector->cmdline_mode;
uint64_t valid_mask = 0;
int i, rotation;

@@ -2540,6 +2541,9 @@ static void drm_setup_crtc_rotation(struct drm_fb_helper *fb_helper,
rotation = DRM_MODE_ROTATE_0;
}

+ if (mode->rotation != DRM_MODE_ROTATE_0)
+ fb_crtc->rotation = mode->rotation;
+
/*
* TODO: support 90 / 270 degree hardware rotation,
* depending on the hardware this may require the framebuffer
diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index 9613c1a28487..ac8d70b92b62 100644
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -1531,6 +1531,71 @@ static int drm_mode_parse_cmdline_res_mode(const char *str, unsigned int length,
return 0;
}

+static int drm_mode_parse_cmdline_options(char *str, size_t len,
+ struct drm_connector *connector,
+ struct drm_cmdline_mode *mode)
+{
+ unsigned int rotation = 0;
+ char *sep = str;
+
+ while ((sep = strchr(sep, ','))) {
+ char *delim, *option;
+
+ option = sep + 1;
+ delim = strchr(option, '=');
+ if (!delim) {
+ delim = strchr(option, ',');
+
+ if (!delim)
+ delim = str + len;
+ }
+
+ if (!strncmp(option, "rotate", delim - option)) {
+ const char *value = delim + 1;
+ unsigned int deg;
+
+ deg = simple_strtol(value, &sep, 10);
+
+ /* Make sure we have parsed something */
+ if (sep == value)
+ return -EINVAL;
+
+ switch (deg) {
+ case 0:
+ rotation |= DRM_MODE_ROTATE_0;
+ break;
+
+ case 90:
+ rotation |= DRM_MODE_ROTATE_90;
+ break;
+
+ case 180:
+ rotation |= DRM_MODE_ROTATE_180;
+ break;
+
+ case 270:
+ rotation |= DRM_MODE_ROTATE_270;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+ } else if (!strncmp(option, "reflect_x", delim - option)) {
+ rotation |= DRM_MODE_REFLECT_X;
+ sep = delim;
+ } else if (!strncmp(option, "reflect_y", delim - option)) {
+ rotation |= DRM_MODE_REFLECT_Y;
+ sep = delim;
+ } else {
+ return -EINVAL;
+ }
+ }
+
+ mode->rotation = rotation;
+
+ return 0;
+}
+
/**
* drm_mode_parse_command_line_for_connector - parse command line modeline for connector
* @mode_option: optional per connector mode option
@@ -1558,9 +1623,10 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
{
const char *name;
bool named_mode = false, parse_extras = false;
- unsigned int bpp_off = 0, refresh_off = 0;
+ unsigned int bpp_off = 0, refresh_off = 0, options_off = 0;
unsigned int mode_end = 0;
char *bpp_ptr = NULL, *refresh_ptr = NULL, *extra_ptr = NULL;
+ char *options_ptr = NULL;
char *bpp_end_ptr = NULL, *refresh_end_ptr = NULL;
int ret;

@@ -1601,13 +1667,18 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
mode->refresh_specified = true;
}

+ /* Locate the start of named options */
+ options_ptr = strchr(name, ',');
+ if (options_ptr)
+ options_off = options_ptr - name;
+
/* 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) {
+ if (bpp_ptr) {
mode_end = bpp_off;
} else if (refresh_ptr) {
mode_end = refresh_off;
+ } else if (options_ptr) {
+ mode_end = options_off;
} else {
mode_end = strlen(name);
parse_extras = true;
@@ -1649,24 +1720,23 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
else if (refresh_ptr)
extra_ptr = refresh_end_ptr;

- if (extra_ptr) {
- if (!named_mode) {
- int len = strlen(name) - (extra_ptr - name);
+ if (extra_ptr &&
+ extra_ptr != options_ptr) {
+ int len = strlen(name) - (extra_ptr - name);

- ret = drm_mode_parse_cmdline_extra(extra_ptr, len,
- connector, mode);
- if (ret)
- return false;
- } else {
- int remaining = strlen(name) - (extra_ptr - name);
+ ret = drm_mode_parse_cmdline_extra(extra_ptr, len,
+ connector, mode);
+ if (ret)
+ return false;
+ }

- /*
- * We still have characters to process, while
- * we shouldn't have any
- */
- if (remaining > 0)
- return false;
- }
+ if (options_ptr) {
+ int len = strlen(name) - (options_ptr - name);
+
+ ret = drm_mode_parse_cmdline_options(options_ptr, len,
+ connector, mode);
+ if (ret)
+ return false;
}

return true;
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 06aa3b9cb920..dfe7f2304b35 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -907,6 +907,7 @@ struct drm_cmdline_mode {
bool interlace;
bool cvt;
bool margins;
+ unsigned int rotation;
enum drm_connector_force force;
};

--
git-series 0.9.1