[PATCH v2 1/5] video: fbdev: ssd1307fb: Propagate errors via ssd1307fb_update_display()

From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Sam Ravnborg <sam@ravnborg.org>, Maxime Ripard <mripard@kernel.org>
Cc: linux-fbdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
	linux-kernel@vger.kernel.org,
	Geert Uytterhoeven <geert@linux-m68k.org>
Subject: [PATCH v2 1/5] video: fbdev: ssd1307fb: Propagate errors via ssd1307fb_update_display()
Date: Tue, 27 Jul 2021 15:47:26 +0200	[thread overview]
Message-ID: <20210727134730.3765898-2-geert@linux-m68k.org> (raw)
In-Reply-To: <20210727134730.3765898-1-geert@linux-m68k.org>

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

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
---
v2:
  - Add Acked-by.
---
 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

