[PATCH 20/99] fbdev/efifb: Parse option string with struct option_iter

[Thomas Zimmermann]

Use struct option_iter to walk over the individual options in the
driver's option string. Replaces the hand-written strsep() loop with
a clean interface. The helpers for struct option_iter handle empty
option strings and empty options transparently. The struct's _init
and _release functions duplicate and release the option string's
memory buffer as needed.

Done in preparation of constifying the option string.

Signed-off-by: Thomas Zimmermann <tzimmermann at suse.de>
---
 drivers/video/fbdev/efifb.c | 46 +++++++++++++++++++------------------
 1 file changed, 24 insertions(+), 22 deletions(-)

diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
index a5779fb453a2..1ae7574aaa82 100644
--- a/drivers/video/fbdev/efifb.c
+++ b/drivers/video/fbdev/efifb.c
@@ -8,6 +8,7 @@
  */
 
 #include <linux/aperture.h>
+#include <linux/cmdline.h>
 #include <linux/kernel.h>
 #include <linux/efi.h>
 #include <linux/efi-bgrt.h>
@@ -284,31 +285,32 @@ static const struct fb_ops efifb_ops = {
 	.fb_imageblit	= cfb_imageblit,
 };
 
-static int efifb_setup(char *options)
+static int efifb_setup(const char *options)
 {
-	char *this_opt;
-
-	if (options && *options) {
-		while ((this_opt = strsep(&options, ",")) != NULL) {
-			if (!*this_opt) continue;
-
-			efifb_setup_from_dmi(&screen_info, this_opt);
-
-			if (!strncmp(this_opt, "base:", 5))
-				screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0);
-			else if (!strncmp(this_opt, "stride:", 7))
-				screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
-			else if (!strncmp(this_opt, "height:", 7))
-				screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0);
-			else if (!strncmp(this_opt, "width:", 6))
-				screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0);
-			else if (!strcmp(this_opt, "nowc"))
-				mem_flags &= ~EFI_MEMORY_WC;
-			else if (!strcmp(this_opt, "nobgrt"))
-				use_bgrt = false;
-		}
+	struct option_iter iter;
+	const char *this_opt;
+
+	option_iter_init(&iter, options);
+
+	while (option_iter_next(&iter, this_opt)) {
+		efifb_setup_from_dmi(&screen_info, this_opt);
+
+		if (!strncmp(this_opt, "base:", 5))
+			screen_info.lfb_base = simple_strtoul(this_opt+5, NULL, 0);
+		else if (!strncmp(this_opt, "stride:", 7))
+			screen_info.lfb_linelength = simple_strtoul(this_opt+7, NULL, 0) * 4;
+		else if (!strncmp(this_opt, "height:", 7))
+			screen_info.lfb_height = simple_strtoul(this_opt+7, NULL, 0);
+		else if (!strncmp(this_opt, "width:", 6))
+			screen_info.lfb_width = simple_strtoul(this_opt+6, NULL, 0);
+		else if (!strcmp(this_opt, "nowc"))
+			mem_flags &= ~EFI_MEMORY_WC;
+		else if (!strcmp(this_opt, "nobgrt"))
+			use_bgrt = false;
 	}
 
+	option_iter_release(&iter);
+
 	return 0;
 }
 
-- 
2.39.2