linux/drivers/media/i2c/lm3646.c
Colin Ian King ecfaec43e4 media: lm3646: remove redundant assignment to variable rval
The variable rval is being initialized with a value that
is never read and is being re-assigned a little later on. The
assignment is redundant and hence can be removed.

Addresses-Coverity: ("Unused value")

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-10-24 18:41:31 -03:00

413 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* drivers/media/i2c/lm3646.c
* General device driver for TI lm3646, Dual FLASH LED Driver
*
* Copyright (C) 2014 Texas Instruments
*
* Contact: Daniel Jeong <gshark.jeong@gmail.com>
* Ldd-Mlp <ldd-mlp@list.ti.com>
*/
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/regmap.h>
#include <linux/videodev2.h>
#include <media/i2c/lm3646.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>
/* registers definitions */
#define REG_ENABLE 0x01
#define REG_TORCH_BR 0x05
#define REG_FLASH_BR 0x05
#define REG_FLASH_TOUT 0x04
#define REG_FLAG 0x08
#define REG_STROBE_SRC 0x06
#define REG_LED1_FLASH_BR 0x06
#define REG_LED1_TORCH_BR 0x07
#define MASK_ENABLE 0x03
#define MASK_TORCH_BR 0x70
#define MASK_FLASH_BR 0x0F
#define MASK_FLASH_TOUT 0x07
#define MASK_FLAG 0xFF
#define MASK_STROBE_SRC 0x80
/* Fault Mask */
#define FAULT_TIMEOUT (1<<0)
#define FAULT_SHORT_CIRCUIT (1<<1)
#define FAULT_UVLO (1<<2)
#define FAULT_IVFM (1<<3)
#define FAULT_OCP (1<<4)
#define FAULT_OVERTEMP (1<<5)
#define FAULT_NTC_TRIP (1<<6)
#define FAULT_OVP (1<<7)
enum led_mode {
MODE_SHDN = 0x0,
MODE_TORCH = 0x2,
MODE_FLASH = 0x3,
};
/*
* struct lm3646_flash
*
* @pdata: platform data
* @regmap: reg. map for i2c
* @lock: muxtex for serial access.
* @led_mode: V4L2 LED mode
* @ctrls_led: V4L2 controls
* @subdev_led: V4L2 subdev
* @mode_reg : mode register value
*/
struct lm3646_flash {
struct device *dev;
struct lm3646_platform_data *pdata;
struct regmap *regmap;
struct v4l2_ctrl_handler ctrls_led;
struct v4l2_subdev subdev_led;
u8 mode_reg;
};
#define to_lm3646_flash(_ctrl) \
container_of(_ctrl->handler, struct lm3646_flash, ctrls_led)
/* enable mode control */
static int lm3646_mode_ctrl(struct lm3646_flash *flash,
enum v4l2_flash_led_mode led_mode)
{
switch (led_mode) {
case V4L2_FLASH_LED_MODE_NONE:
return regmap_write(flash->regmap,
REG_ENABLE, flash->mode_reg | MODE_SHDN);
case V4L2_FLASH_LED_MODE_TORCH:
return regmap_write(flash->regmap,
REG_ENABLE, flash->mode_reg | MODE_TORCH);
case V4L2_FLASH_LED_MODE_FLASH:
return regmap_write(flash->regmap,
REG_ENABLE, flash->mode_reg | MODE_FLASH);
}
return -EINVAL;
}
/* V4L2 controls */
static int lm3646_get_ctrl(struct v4l2_ctrl *ctrl)
{
struct lm3646_flash *flash = to_lm3646_flash(ctrl);
unsigned int reg_val;
int rval;
if (ctrl->id != V4L2_CID_FLASH_FAULT)
return -EINVAL;
rval = regmap_read(flash->regmap, REG_FLAG, &reg_val);
if (rval < 0)
return rval;
ctrl->val = 0;
if (reg_val & FAULT_TIMEOUT)
ctrl->val |= V4L2_FLASH_FAULT_TIMEOUT;
if (reg_val & FAULT_SHORT_CIRCUIT)
ctrl->val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
if (reg_val & FAULT_UVLO)
ctrl->val |= V4L2_FLASH_FAULT_UNDER_VOLTAGE;
if (reg_val & FAULT_IVFM)
ctrl->val |= V4L2_FLASH_FAULT_INPUT_VOLTAGE;
if (reg_val & FAULT_OCP)
ctrl->val |= V4L2_FLASH_FAULT_OVER_CURRENT;
if (reg_val & FAULT_OVERTEMP)
ctrl->val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
if (reg_val & FAULT_NTC_TRIP)
ctrl->val |= V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE;
if (reg_val & FAULT_OVP)
ctrl->val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;
return 0;
}
static int lm3646_set_ctrl(struct v4l2_ctrl *ctrl)
{
struct lm3646_flash *flash = to_lm3646_flash(ctrl);
unsigned int reg_val;
int rval;
switch (ctrl->id) {
case V4L2_CID_FLASH_LED_MODE:
if (ctrl->val != V4L2_FLASH_LED_MODE_FLASH)
return lm3646_mode_ctrl(flash, ctrl->val);
/* switch to SHDN mode before flash strobe on */
return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
case V4L2_CID_FLASH_STROBE_SOURCE:
return regmap_update_bits(flash->regmap,
REG_STROBE_SRC, MASK_STROBE_SRC,
(ctrl->val) << 7);
case V4L2_CID_FLASH_STROBE:
/* read and check current mode of chip to start flash */
rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
if (rval < 0 || ((reg_val & MASK_ENABLE) != MODE_SHDN))
return rval;
/* flash on */
return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_FLASH);
case V4L2_CID_FLASH_STROBE_STOP:
/*
* flash mode will be turned automatically
* from FLASH mode to SHDN mode after flash duration timeout
* read and check current mode of chip to stop flash
*/
rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
if (rval < 0)
return rval;
if ((reg_val & MASK_ENABLE) == MODE_FLASH)
return lm3646_mode_ctrl(flash,
V4L2_FLASH_LED_MODE_NONE);
return rval;
case V4L2_CID_FLASH_TIMEOUT:
return regmap_update_bits(flash->regmap,
REG_FLASH_TOUT, MASK_FLASH_TOUT,
LM3646_FLASH_TOUT_ms_TO_REG
(ctrl->val));
case V4L2_CID_FLASH_INTENSITY:
return regmap_update_bits(flash->regmap,
REG_FLASH_BR, MASK_FLASH_BR,
LM3646_TOTAL_FLASH_BRT_uA_TO_REG
(ctrl->val));
case V4L2_CID_FLASH_TORCH_INTENSITY:
return regmap_update_bits(flash->regmap,
REG_TORCH_BR, MASK_TORCH_BR,
LM3646_TOTAL_TORCH_BRT_uA_TO_REG
(ctrl->val) << 4);
}
return -EINVAL;
}
static const struct v4l2_ctrl_ops lm3646_led_ctrl_ops = {
.g_volatile_ctrl = lm3646_get_ctrl,
.s_ctrl = lm3646_set_ctrl,
};
static int lm3646_init_controls(struct lm3646_flash *flash)
{
struct v4l2_ctrl *fault;
struct v4l2_ctrl_handler *hdl = &flash->ctrls_led;
const struct v4l2_ctrl_ops *ops = &lm3646_led_ctrl_ops;
v4l2_ctrl_handler_init(hdl, 8);
/* flash mode */
v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_LED_MODE,
V4L2_FLASH_LED_MODE_TORCH, ~0x7,
V4L2_FLASH_LED_MODE_NONE);
/* flash source */
v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_STROBE_SOURCE,
0x1, ~0x3, V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
/* flash strobe */
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
/* flash strobe stop */
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);
/* flash strobe timeout */
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TIMEOUT,
LM3646_FLASH_TOUT_MIN,
LM3646_FLASH_TOUT_MAX,
LM3646_FLASH_TOUT_STEP, flash->pdata->flash_timeout);
/* max flash current */
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_INTENSITY,
LM3646_TOTAL_FLASH_BRT_MIN,
LM3646_TOTAL_FLASH_BRT_MAX,
LM3646_TOTAL_FLASH_BRT_STEP,
LM3646_TOTAL_FLASH_BRT_MAX);
/* max torch current */
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TORCH_INTENSITY,
LM3646_TOTAL_TORCH_BRT_MIN,
LM3646_TOTAL_TORCH_BRT_MAX,
LM3646_TOTAL_TORCH_BRT_STEP,
LM3646_TOTAL_TORCH_BRT_MAX);
/* fault */
fault = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_FAULT, 0,
V4L2_FLASH_FAULT_OVER_VOLTAGE
| V4L2_FLASH_FAULT_OVER_TEMPERATURE
| V4L2_FLASH_FAULT_SHORT_CIRCUIT
| V4L2_FLASH_FAULT_TIMEOUT, 0, 0);
if (fault != NULL)
fault->flags |= V4L2_CTRL_FLAG_VOLATILE;
if (hdl->error)
return hdl->error;
flash->subdev_led.ctrl_handler = hdl;
return 0;
}
/* initialize device */
static const struct v4l2_subdev_ops lm3646_ops = {
.core = NULL,
};
static const struct regmap_config lm3646_regmap = {
.reg_bits = 8,
.val_bits = 8,
.max_register = 0xFF,
};
static int lm3646_subdev_init(struct lm3646_flash *flash)
{
struct i2c_client *client = to_i2c_client(flash->dev);
int rval;
v4l2_i2c_subdev_init(&flash->subdev_led, client, &lm3646_ops);
flash->subdev_led.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
strscpy(flash->subdev_led.name, LM3646_NAME,
sizeof(flash->subdev_led.name));
rval = lm3646_init_controls(flash);
if (rval)
goto err_out;
rval = media_entity_pads_init(&flash->subdev_led.entity, 0, NULL);
if (rval < 0)
goto err_out;
flash->subdev_led.entity.function = MEDIA_ENT_F_FLASH;
return rval;
err_out:
v4l2_ctrl_handler_free(&flash->ctrls_led);
return rval;
}
static int lm3646_init_device(struct lm3646_flash *flash)
{
unsigned int reg_val;
int rval;
/* read the value of mode register to reduce redundant i2c accesses */
rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
if (rval < 0)
return rval;
flash->mode_reg = reg_val & 0xfc;
/* output disable */
rval = lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
if (rval < 0)
return rval;
/*
* LED1 flash current setting
* LED2 flash current = Total(Max) flash current - LED1 flash current
*/
rval = regmap_update_bits(flash->regmap,
REG_LED1_FLASH_BR, 0x7F,
LM3646_LED1_FLASH_BRT_uA_TO_REG
(flash->pdata->led1_flash_brt));
if (rval < 0)
return rval;
/*
* LED1 torch current setting
* LED2 torch current = Total(Max) torch current - LED1 torch current
*/
rval = regmap_update_bits(flash->regmap,
REG_LED1_TORCH_BR, 0x7F,
LM3646_LED1_TORCH_BRT_uA_TO_REG
(flash->pdata->led1_torch_brt));
if (rval < 0)
return rval;
/* Reset flag register */
return regmap_read(flash->regmap, REG_FLAG, &reg_val);
}
static int lm3646_probe(struct i2c_client *client,
const struct i2c_device_id *devid)
{
struct lm3646_flash *flash;
struct lm3646_platform_data *pdata = dev_get_platdata(&client->dev);
int rval;
flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
if (flash == NULL)
return -ENOMEM;
flash->regmap = devm_regmap_init_i2c(client, &lm3646_regmap);
if (IS_ERR(flash->regmap))
return PTR_ERR(flash->regmap);
/* check device tree if there is no platform data */
if (pdata == NULL) {
pdata = devm_kzalloc(&client->dev,
sizeof(struct lm3646_platform_data),
GFP_KERNEL);
if (pdata == NULL)
return -ENOMEM;
/* use default data in case of no platform data */
pdata->flash_timeout = LM3646_FLASH_TOUT_MAX;
pdata->led1_torch_brt = LM3646_LED1_TORCH_BRT_MAX;
pdata->led1_flash_brt = LM3646_LED1_FLASH_BRT_MAX;
}
flash->pdata = pdata;
flash->dev = &client->dev;
rval = lm3646_subdev_init(flash);
if (rval < 0)
return rval;
rval = lm3646_init_device(flash);
if (rval < 0)
return rval;
i2c_set_clientdata(client, flash);
return 0;
}
static int lm3646_remove(struct i2c_client *client)
{
struct lm3646_flash *flash = i2c_get_clientdata(client);
v4l2_device_unregister_subdev(&flash->subdev_led);
v4l2_ctrl_handler_free(&flash->ctrls_led);
media_entity_cleanup(&flash->subdev_led.entity);
return 0;
}
static const struct i2c_device_id lm3646_id_table[] = {
{LM3646_NAME, 0},
{}
};
MODULE_DEVICE_TABLE(i2c, lm3646_id_table);
static struct i2c_driver lm3646_i2c_driver = {
.driver = {
.name = LM3646_NAME,
},
.probe = lm3646_probe,
.remove = lm3646_remove,
.id_table = lm3646_id_table,
};
module_i2c_driver(lm3646_i2c_driver);
MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
MODULE_DESCRIPTION("Texas Instruments LM3646 Dual Flash LED driver");
MODULE_LICENSE("GPL");