From 3942bb49728ad9e1f94d953a88af169a8f5d8099 Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Wed, 14 Aug 2024 13:00:34 +0300 Subject: string: add mem_is_zero() helper to check if memory area is all zeros Almost two thirds of the memchr_inv() usages check if the memory area is all zeros, with no interest in where in the buffer the first non-zero byte is located. Checking for !memchr_inv(s, 0, n) is also not very intuitive or discoverable. Add an explicit mem_is_zero() helper for this use case. Reviewed-by: Kees Cook Reviewed-by: Andy Shevchenko Link: https://patchwork.freedesktop.org/patch/msgid/20240814100035.3100852-1-jani.nikula@intel.com Signed-off-by: Jani Nikula --- include/linux/string.h | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'include') diff --git a/include/linux/string.h b/include/linux/string.h index 9edace076ddb..5855c5626b4b 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -279,6 +279,18 @@ static inline void memcpy_flushcache(void *dst, const void *src, size_t cnt) void *memchr_inv(const void *s, int c, size_t n); char *strreplace(char *str, char old, char new); +/** + * mem_is_zero - Check if an area of memory is all 0's. + * @s: The memory area + * @n: The size of the area + * + * Return: True if the area of memory is all 0's. + */ +static inline bool mem_is_zero(const void *s, size_t n) +{ + return !memchr_inv(s, 0, n); +} + extern void kfree_const(const void *x); extern char *kstrdup(const char *s, gfp_t gfp) __malloc; -- cgit v1.2.3 From 051c86afc342aed1f84d66ff5d09dc9e1c1685a1 Mon Sep 17 00:00:00 2001 From: Tejas Vipin Date: Sun, 18 Aug 2024 11:38:15 +0530 Subject: drm/mipi-dsi: Add mipi_dsi_dcs_set_tear_scanline_multi mipi_dsi_dcs_set_tear_scanline_multi can heavily benefit from being converted to a multi style function as it is often called in the context of similar functions. Reviewed-by: Douglas Anderson Signed-off-by: Tejas Vipin Signed-off-by: Douglas Anderson Link: https://patchwork.freedesktop.org/patch/msgid/20240818060816.848784-2-tejasvipin76@gmail.com --- include/drm/drm_mipi_dsi.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h index b78aae45cae7..f725f8654611 100644 --- a/include/drm/drm_mipi_dsi.h +++ b/include/drm/drm_mipi_dsi.h @@ -375,6 +375,8 @@ void mipi_dsi_dcs_set_column_address_multi(struct mipi_dsi_multi_context *ctx, u16 start, u16 end); void mipi_dsi_dcs_set_page_address_multi(struct mipi_dsi_multi_context *ctx, u16 start, u16 end); +void mipi_dsi_dcs_set_tear_scanline_multi(struct mipi_dsi_multi_context *ctx, + u16 scanline); /** * mipi_dsi_generic_write_seq - transmit data using a generic write packet -- cgit v1.2.3