Re: [PATCHv2 07/10] fbdev: ssd1307fb: Add module parameter to set refresh rate of the display

This patch adds the module parameter "refreshrate" to set delay for the
deferred io. The refresh rate is given in units of Hertz. The default
refresh rate is 1 Hz.

Signed-off-by: Thomas Niederprüm <redacted>
---
 drivers/video/fbdev/ssd1307fb.c | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index c7ed287..ea58e87 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c

@@ -43,6 +43,11 @@
 #define	SSD1307FB_SET_COM_PINS_CONFIG	0xda
 #define	SSD1307FB_SET_VCOMH		0xdb
 
+#define REFRASHRATE 1
+
+static u_int refreshrate = REFRASHRATE;
+module_param(refreshrate, uint, 0);
+
 static u_int contrast = 128;
 module_param(contrast, uint, S_IRUGO);
 

@@ -270,11 +275,6 @@ static void ssd1307fb_deferred_io(struct fb_info *info,
 	ssd1307fb_update_display(info->par);
 }
 
-static struct fb_deferred_io ssd1307fb_defio = {
-	.delay		= HZ,
-	.deferred_io	= ssd1307fb_deferred_io,
-};
-
 static int ssd1307fb_init(struct ssd1307fb_par *par)
 {
 	int ret;

@@ -475,6 +475,7 @@ static int ssd1307fb_probe(struct i2c_client *client,
 {
 	struct fb_info *info;
 	struct device_node *node = client->dev.of_node;
+	struct fb_deferred_io *ssd1307fb_defio;
 	u32 vmem_size;
 	struct ssd1307fb_par *par;
 	u8 *vmem;

@@ -544,10 +545,20 @@ static int ssd1307fb_probe(struct i2c_client *client,
 		goto fb_alloc_error;
 	}
 
+	ssd1307fb_defio = devm_kzalloc(&client->dev, sizeof(struct fb_deferred_io), GFP_KERNEL);
+	if (!ssd1307fb_defio) {
+		dev_err(&client->dev, "Couldn't allocate deferred io.\n");
+		ret = -ENOMEM;
+		goto fb_alloc_error;
+	}
+
+	ssd1307fb_defio->delay = HZ/refreshrate;