[PATCH resend 1/5] video: fbdev: ssd1307fb: Propagate errors via ssd1307fb_update_display()

From: Geert Uytterhoeven
Date: Wed Jul 14 2021 - 10:58:15 EST


Make ssd1307fb_update_display() return an error code, so callers that
can handle failures can propagate it.

Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
---
drivers/video/fbdev/ssd1307fb.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index eda448b7a0c9d8ce..e6b6263e3bef847f 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -152,17 +152,17 @@ static inline int ssd1307fb_write_cmd(struct i2c_client *client, u8 cmd)
return ret;
}

-static void ssd1307fb_update_display(struct ssd1307fb_par *par)
+static int ssd1307fb_update_display(struct ssd1307fb_par *par)
{
struct ssd1307fb_array *array;
u8 *vmem = par->info->screen_buffer;
unsigned int line_length = par->info->fix.line_length;
unsigned int pages = DIV_ROUND_UP(par->height, 8);
- int i, j, k;
+ int ret, i, j, k;

array = ssd1307fb_alloc_array(par->width * pages, SSD1307FB_DATA);
if (!array)
- return;
+ return -ENOMEM;

/*
* The screen is divided in pages, each having a height of 8
@@ -210,8 +210,9 @@ static void ssd1307fb_update_display(struct ssd1307fb_par *par)
}
}

- ssd1307fb_write_array(par->client, array, par->width * pages);
+ ret = ssd1307fb_write_array(par->client, array, par->width * pages);
kfree(array);
+ return ret;
}


@@ -222,6 +223,7 @@ static ssize_t ssd1307fb_write(struct fb_info *info, const char __user *buf,
unsigned long total_size;
unsigned long p = *ppos;
void *dst;
+ int ret;

total_size = info->fix.smem_len;

@@ -239,7 +241,9 @@ static ssize_t ssd1307fb_write(struct fb_info *info, const char __user *buf,
if (copy_from_user(dst, buf, count))
return -EFAULT;

- ssd1307fb_update_display(par);
+ ret = ssd1307fb_update_display(par);
+ if (ret < 0)
+ return ret;

*ppos += count;

@@ -483,7 +487,9 @@ static int ssd1307fb_init(struct ssd1307fb_par *par)
return ret;

/* Clear the screen */
- ssd1307fb_update_display(par);
+ ret = ssd1307fb_update_display(par);
+ if (ret < 0)
+ return ret;

/* Turn on the display */
ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
--
2.25.1