linux/drivers/media/i2c/ov7640.c
Moses Christopher Bollavarapu 378a0e4ba8 media: ov7640: Use ARRAY_SIZE instead of manual checking
Currently, the driver ends the reg-val list with a 0xFF as a check to stop
the loop. Instead an array of reg-vals can be used to avoid this check,
by using the ARRAY_SIZE(arr) macro to obtain the length of the array and
iterate over it.

Signed-off-by: Moses Christopher Bollavarapu <mosescb.dev@gmail.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
2022-04-24 08:25:08 +01:00

97 lines
1.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2005-2006 Micronas USA Inc.
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
#include <linux/slab.h>
MODULE_DESCRIPTION("OmniVision ov7640 sensor driver");
MODULE_LICENSE("GPL v2");
struct reg_val {
u8 reg;
u8 val;
};
static const struct reg_val regval_init[] = {
{0x12, 0x80},
{0x12, 0x54},
{0x14, 0x24},
{0x15, 0x01},
{0x28, 0x20},
{0x75, 0x82},
};
static int write_regs(struct i2c_client *client,
const struct reg_val *rv, int len)
{
while (--len >= 0) {
if (i2c_smbus_write_byte_data(client, rv->reg, rv->val) < 0)
return -1;
rv++;
}
return 0;
}
/* ----------------------------------------------------------------------- */
static const struct v4l2_subdev_ops ov7640_ops;
static int ov7640_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct i2c_adapter *adapter = client->adapter;
struct v4l2_subdev *sd;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
sd = devm_kzalloc(&client->dev, sizeof(*sd), GFP_KERNEL);
if (sd == NULL)
return -ENOMEM;
v4l2_i2c_subdev_init(sd, client, &ov7640_ops);
client->flags = I2C_CLIENT_SCCB;
v4l_info(client, "chip found @ 0x%02x (%s)\n",
client->addr << 1, client->adapter->name);
if (write_regs(client, regval_init, ARRAY_SIZE(regval_init)) < 0) {
v4l_err(client, "error initializing OV7640\n");
return -ENODEV;
}
return 0;
}
static int ov7640_remove(struct i2c_client *client)
{
struct v4l2_subdev *sd = i2c_get_clientdata(client);
v4l2_device_unregister_subdev(sd);
return 0;
}
static const struct i2c_device_id ov7640_id[] = {
{ "ov7640", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ov7640_id);
static struct i2c_driver ov7640_driver = {
.driver = {
.name = "ov7640",
},
.probe = ov7640_probe,
.remove = ov7640_remove,
.id_table = ov7640_id,
};
module_i2c_driver(ov7640_driver);