Commit 9f7714d4 authored by Maxime Ripard's avatar Maxime Ripard Committed by Tomi Valkeinen
Browse files

video: ssd1307fb: Rework the communication functions 



To efficiently send a whole page to the display, we need to be able to
manipulate more easily the data arrays that has to be sent to the OLED
controller. As such, this patch introduces a ssd1307fb_array structure
that handles both the small header to be sent over i2c, which contains
the type of information sent, and the raw bytes after that.

Signed-off-by: default avatarMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ti.com>
parent bbc79089

drivers/video/ssd1307fb.c

+50 −27
Original line number Diff line number Diff line
@@ -51,6 +51,11 @@ struct ssd1307fb_par { 
	u32 width;

};



struct ssd1307fb_array {

	u8	type;

	u8	data[0];

};



static struct fb_fix_screeninfo ssd1307fb_fix = {

	.id		= "Solomon SSD1307",

	.type		= FB_TYPE_PACKED_PIXELS,
@@ -65,49 +70,67 @@ static struct fb_var_screeninfo ssd1307fb_var = { 
	.bits_per_pixel	= 1,

};



static int ssd1307fb_write_array(struct i2c_client *client, u8 type, u8 *cmd, u32 len)

static struct ssd1307fb_array *ssd1307fb_alloc_array(u32 len, u8 type)

{

	u8 *buf;

	int ret = 0;

	struct ssd1307fb_array *array;



	buf = kzalloc(len + 1, GFP_KERNEL);

	if (!buf) {

		dev_err(&client->dev, "Couldn't allocate sending buffer.\n");

		return -ENOMEM;

	}

	array = kzalloc(sizeof(struct ssd1307fb_array) + len, GFP_KERNEL);

	if (!array)

		return NULL;



	buf[0] = type;

	memcpy(buf + 1, cmd, len);

	array->type = type;



	ret = i2c_master_send(client, buf, len + 1);

	if (ret != len + 1) {

		dev_err(&client->dev, "Couldn't send I2C command.\n");

		goto error;

	return array;

}



error:

	kfree(buf);

static int ssd1307fb_write_array(struct i2c_client *client,

				 struct ssd1307fb_array *array, u32 len)

{

	int ret;



	len += sizeof(struct ssd1307fb_array);



	ret = i2c_master_send(client, (u8 *)array, len);

	if (ret != len) {

		dev_err(&client->dev, "Couldn't send I2C command.\n");

		return ret;

	}



static inline int ssd1307fb_write_cmd_array(struct i2c_client *client, u8 *cmd, u32 len)

{

	return ssd1307fb_write_array(client, SSD1307FB_COMMAND, cmd, len);

	return 0;

}



static inline int ssd1307fb_write_cmd(struct i2c_client *client, u8 cmd)

{

	return ssd1307fb_write_cmd_array(client, &cmd, 1);

}

	struct ssd1307fb_array *array;

	int ret;



static inline int ssd1307fb_write_data_array(struct i2c_client *client, u8 *cmd, u32 len)

{

	return ssd1307fb_write_array(client, SSD1307FB_DATA, cmd, len);

	array = ssd1307fb_alloc_array(1, SSD1307FB_COMMAND);

	if (!array)

		return -ENOMEM;



	array->data[0] = cmd;



	ret = ssd1307fb_write_array(client, array, 1);

	kfree(array);



	return ret;

}



static inline int ssd1307fb_write_data(struct i2c_client *client, u8 data)

{

	return ssd1307fb_write_data_array(client, &data, 1);

	struct ssd1307fb_array *array;

	int ret;



	array = ssd1307fb_alloc_array(1, SSD1307FB_DATA);

	if (!array)

		return -ENOMEM;



	array->data[0] = data;



	ret = ssd1307fb_write_array(client, array, 1);

	kfree(array);



	return ret;

}



static void ssd1307fb_update_display(struct ssd1307fb_par *par)

CRA Git | Maintained and supported by SUSTech CRA and CCSE