drm/modes: parse_cmdline: Rework drm_mode_parse_cmdline_options()

Refactor drm_mode_parse_cmdline_options() so that it takes a pointer
to the first option, rather then a pointer to the ',' before the first
option.

This is a preparation patch for allowing parsing of stand-alone options
without a mode before them, e.g.: video=HDMI-1:margin_right=14,...

Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191118155134.30468-5-hdegoede@redhat.com

diff --git a/drivers/gpu/drm/drm_modes.c b/drivers/gpu/drm/drm_modes.c
index f49401124727385419ecfb02a9a3d11e43d6e51a..25e8edf4cfb8c4e68291ed0aaf20f94a5d931266 100644 (file)
--- a/drivers/gpu/drm/drm_modes.c
+++ b/drivers/gpu/drm/drm_modes.c
@@ -1591,23 +1591,21 @@ static int drm_mode_parse_cmdline_int(const char *delim, unsigned int *int_ret)
        return 0;
 }
 
-static int drm_mode_parse_cmdline_options(const char *str, size_t len,
+static int drm_mode_parse_cmdline_options(const char *str,
                                          const struct drm_connector *connector,
                                          struct drm_cmdline_mode *mode)
 {
        unsigned int deg, margin, rotation = 0;
-       const char *sep = str;
+       const char *delim, *option, *sep;
 
-       while ((sep = strchr(sep, ','))) {
-               const char *delim, *option;
-
-               option = sep + 1;
+       option = str;
+       do {
                delim = strchr(option, '=');
                if (!delim) {
                        delim = strchr(option, ',');
 
                        if (!delim)
-                               delim = str + len;
+                               delim = option + strlen(option);
                }
 
                if (!strncmp(option, "rotate", delim - option)) {
@@ -1661,8 +1659,9 @@ static int drm_mode_parse_cmdline_options(const char *str, size_t len,
                } else {
                        return -EINVAL;
                }
-               sep = delim;
-       }
+               sep = strchr(delim, ',');
+               option = sep + 1;
+       } while (sep);
 
        mode->rotation_reflection = rotation;
 
@@ -1855,9 +1854,7 @@ bool drm_mode_parse_command_line_for_connector(const char *mode_option,
        }
 
        if (options_ptr) {
-               int len = strlen(name) - (options_ptr - name);
-
-               ret = drm_mode_parse_cmdline_options(options_ptr, len,
+               ret = drm_mode_parse_cmdline_options(options_ptr + 1,
                                                     connector, mode);
                if (ret)
                        return false;