Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 070ed82e authored by Sakari Ailus's avatar Sakari Ailus Committed by Mauro Carvalho Chehab
Browse files

media: et8ek8: Decrease stack usage 



The et8ek8 driver combines I²C register writes to a single array that it
passes to i2c_transfer(). The maximum number of writes is 48 at once,
decrease it to 8 and make more transfers if needed.

Signed-off-by: default avatarSakari Ailus <sakari.ailus@linux.intel.com>
Tested-by: default avatarPavel Machek <pavel@ucw.cz>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@s-opensource.com>
parent 39229620

drivers/media/i2c/et8ek8/et8ek8_driver.c

+17 −9
Original line number Diff line number Diff line
@@ -43,7 +43,7 @@ 


#define ET8EK8_NAME		"et8ek8"

#define ET8EK8_PRIV_MEM_SIZE	128

#define ET8EK8_MAX_MSG		48

#define ET8EK8_MAX_MSG		8



struct et8ek8_sensor {

	struct v4l2_subdev subdev;
@@ -220,7 +220,8 @@ static void et8ek8_i2c_create_msg(struct i2c_client *client, u16 len, u16 reg, 


/*

 * A buffered write method that puts the wanted register write

 * commands in a message list and passes the list to the i2c framework

 * commands in smaller number of message lists and passes the lists to

 * the i2c framework

 */

static int et8ek8_i2c_buffered_write_regs(struct i2c_client *client,

					  const struct et8ek8_reg *wnext,
@@ -231,11 +232,7 @@ static int et8ek8_i2c_buffered_write_regs(struct i2c_client *client, 
	int wcnt = 0;

	u16 reg, data_length;

	u32 val;



	if (WARN_ONCE(cnt > ET8EK8_MAX_MSG,

		      ET8EK8_NAME ": %s: too many messages.\n", __func__)) {

		return -EINVAL;

	}

	int rval;



	/* Create new write messages for all writes */

	while (wcnt < cnt) {
@@ -249,10 +246,21 @@ static int et8ek8_i2c_buffered_write_regs(struct i2c_client *client, 


		/* Update write count */

		wcnt++;



		if (wcnt < ET8EK8_MAX_MSG)

			continue;



		rval = i2c_transfer(client->adapter, msg, wcnt);

		if (rval < 0)

			return rval;



		cnt -= wcnt;

		wcnt = 0;

	}



	/* Now we send everything ... */

	return i2c_transfer(client->adapter, msg, wcnt);

	rval = i2c_transfer(client->adapter, msg, wcnt);



	return rval < 0 ? rval : 0;

}



/*