diff options
| author | Geert Uytterhoeven <geert@linux-m68k.org> | 2021-07-27 15:47:27 +0200 |
|---|---|---|
| committer | Sam Ravnborg <sam@ravnborg.org> | 2021-07-27 17:18:18 +0200 |
| commit | ef9d793825b56ec4289d2b848c9318352fa2cd13 (patch) | |
| tree | 69e488ed8aa05a0d322eecb23e1a18cbf7289a99 /drivers/video | |
| parent | 7b4b3733fd68d986c3f790e47aa6116d229e949e (diff) | |
video: fbdev: ssd1307fb: Simplify ssd1307fb_update_display()
Simplify the nested loops to handle conversion from linear frame buffer
to ssd1307 page layout:
1. Move last page handling one level up, as the value of "m" is the
same inside a page,
2. array->data[] is filled linearly, so there is no need to
recalculate array_idx over and over again; a simple increment is
sufficient.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727134730.3765898-3-geert@linux-m68k.org
Diffstat (limited to 'drivers/video')
| -rw-r--r-- | drivers/video/fbdev/ssd1307fb.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c index e6b6263e3bef..6d7bd025bca1 100644 --- a/drivers/video/fbdev/ssd1307fb.c +++ b/drivers/video/fbdev/ssd1307fb.c @@ -158,6 +158,7 @@ static int ssd1307fb_update_display(struct ssd1307fb_par *par) u8 *vmem = par->info->screen_buffer; unsigned int line_length = par->info->fix.line_length; unsigned int pages = DIV_ROUND_UP(par->height, 8); + u32 array_idx = 0; int ret, i, j, k; array = ssd1307fb_alloc_array(par->width * pages, SSD1307FB_DATA); @@ -194,19 +195,21 @@ static int ssd1307fb_update_display(struct ssd1307fb_par *par) */ for (i = 0; i < pages; i++) { + int m = 8; + + /* Last page may be partial */ + if (i + 1 == pages && par->height % 8) + m = par->height % 8; for (j = 0; j < par->width; j++) { - int m = 8; - u32 array_idx = i * par->width + j; - array->data[array_idx] = 0; - /* Last page may be partial */ - if (i + 1 == pages && par->height % 8) - m = par->height % 8; + u8 data = 0; + for (k = 0; k < m; k++) { u8 byte = vmem[(8 * i + k) * line_length + j / 8]; u8 bit = (byte >> (j % 8)) & 1; - array->data[array_idx] |= bit << k; + data |= bit << k; } + array->data[array_idx++] = data; } } |