[PATCH v2 020/101] fbdev/efifb: Parse option string with struct option_iter

From: Thomas Zimmermann
Date: Thu Mar 09 2023 - 11:05:27 EST


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@xxxxxxx>
---
drivers/video/fbdev/efifb.c | 42 +++++++++++++++++++------------------
1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/drivers/video/fbdev/efifb.c b/drivers/video/fbdev/efifb.c
index a5779fb453a2..be77a76f7d1d 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)
{
+ struct option_iter iter;
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;
- }
+ 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