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linux/drivers/media/i2c/adp1653.c
Arnd Bergmann 287980e49f remove lots of IS_ERR_VALUE abuses 
Most users of IS_ERR_VALUE() in the kernel are wrong, as they
pass an 'int' into a function that takes an 'unsigned long'
argument. This happens to work because the type is sign-extended
on 64-bit architectures before it gets converted into an
unsigned type.

However, anything that passes an 'unsigned short' or 'unsigned int'
argument into IS_ERR_VALUE() is guaranteed to be broken, as are
8-bit integers and types that are wider than 'unsigned long'.

Andrzej Hajda has already fixed a lot of the worst abusers that
were causing actual bugs, but it would be nice to prevent any
users that are not passing 'unsigned long' arguments.

This patch changes all users of IS_ERR_VALUE() that I could find
on 32-bit ARM randconfig builds and x86 allmodconfig. For the
moment, this doesn't change the definition of IS_ERR_VALUE()
because there are probably still architecture specific users
elsewhere.

Almost all the warnings I got are for files that are better off
using 'if (err)' or 'if (err < 0)'.
The only legitimate user I could find that we get a warning for
is the (32-bit only) freescale fman driver, so I did not remove
the IS_ERR_VALUE() there but changed the type to 'unsigned long'.
For 9pfs, I just worked around one user whose calling conventions
are so obscure that I did not dare change the behavior.

I was using this definition for testing:

 #define IS_ERR_VALUE(x) ((unsigned long*)NULL == (typeof (x)*)NULL && \
       unlikely((unsigned long long)(x) >= (unsigned long long)(typeof(x))-MAX_ERRNO))

which ends up making all 16-bit or wider types work correctly with
the most plausible interpretation of what IS_ERR_VALUE() was supposed
to return according to its users, but also causes a compile-time
warning for any users that do not pass an 'unsigned long' argument.

I suggested this approach earlier this year, but back then we ended
up deciding to just fix the users that are obviously broken. After
the initial warning that caused me to get involved in the discussion
(fs/gfs2/dir.c) showed up again in the mainline kernel, Linus
asked me to send the whole thing again.

[ Updated the 9p parts as per Al Viro  - Linus ]

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lkml.org/lkml/2016/1/7/363
Link: https://lkml.org/lkml/2016/5/27/486
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> # For nvmem part
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-27 15:26:11 -07:00

567 lines
14 KiB
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/*
* drivers/media/i2c/adp1653.c
*
* Copyright (C) 2008--2011 Nokia Corporation
*
* Contact: Sakari Ailus <sakari.ailus@iki.fi>
*
* Contributors:
* Sakari Ailus <sakari.ailus@iki.fi>
* Tuukka Toivonen <tuukkat76@gmail.com>
* Pavel Machek <pavel@ucw.cz>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* TODO:
* - fault interrupt handling
* - hardware strobe
* - power doesn't need to be ON if all lights are off
*
*/
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <media/i2c/adp1653.h>
#include <media/v4l2-device.h>
#define TIMEOUT_MAX 820000
#define TIMEOUT_STEP 54600
#define TIMEOUT_MIN (TIMEOUT_MAX - ADP1653_REG_CONFIG_TMR_SET_MAX \
* TIMEOUT_STEP)
#define TIMEOUT_US_TO_CODE(t) ((TIMEOUT_MAX + (TIMEOUT_STEP / 2) - (t)) \
/ TIMEOUT_STEP)
#define TIMEOUT_CODE_TO_US(c) (TIMEOUT_MAX - (c) * TIMEOUT_STEP)
/* Write values into ADP1653 registers. */
static int adp1653_update_hw(struct adp1653_flash *flash)
{
struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
u8 out_sel;
u8 config = 0;
int rval;
out_sel = ADP1653_INDICATOR_INTENSITY_uA_TO_REG(
flash->indicator_intensity->val)
<< ADP1653_REG_OUT_SEL_ILED_SHIFT;
switch (flash->led_mode->val) {
case V4L2_FLASH_LED_MODE_NONE:
break;
case V4L2_FLASH_LED_MODE_FLASH:
/* Flash mode, light on with strobe, duration from timer */
config = ADP1653_REG_CONFIG_TMR_CFG;
config |= TIMEOUT_US_TO_CODE(flash->flash_timeout->val)
<< ADP1653_REG_CONFIG_TMR_SET_SHIFT;
break;
case V4L2_FLASH_LED_MODE_TORCH:
/* Torch mode, light immediately on, duration indefinite */
out_sel |= ADP1653_FLASH_INTENSITY_mA_TO_REG(
flash->torch_intensity->val)
<< ADP1653_REG_OUT_SEL_HPLED_SHIFT;
break;
}
rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, out_sel);
if (rval < 0)
return rval;
rval = i2c_smbus_write_byte_data(client, ADP1653_REG_CONFIG, config);
if (rval < 0)
return rval;
return 0;
}
static int adp1653_get_fault(struct adp1653_flash *flash)
{
struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
int fault;
int rval;
fault = i2c_smbus_read_byte_data(client, ADP1653_REG_FAULT);
if (fault < 0)
return fault;
flash->fault |= fault;
if (!flash->fault)
return 0;
/* Clear faults. */
rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, 0);
if (rval < 0)
return rval;
flash->led_mode->val = V4L2_FLASH_LED_MODE_NONE;
rval = adp1653_update_hw(flash);
if (rval)
return rval;
return flash->fault;
}
static int adp1653_strobe(struct adp1653_flash *flash, int enable)
{
struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
u8 out_sel = ADP1653_INDICATOR_INTENSITY_uA_TO_REG(
flash->indicator_intensity->val)
<< ADP1653_REG_OUT_SEL_ILED_SHIFT;
int rval;
if (flash->led_mode->val != V4L2_FLASH_LED_MODE_FLASH)
return -EBUSY;
if (!enable)
return i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL,
out_sel);
out_sel |= ADP1653_FLASH_INTENSITY_mA_TO_REG(
flash->flash_intensity->val)
<< ADP1653_REG_OUT_SEL_HPLED_SHIFT;
rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, out_sel);
if (rval)
return rval;
/* Software strobe using i2c */
rval = i2c_smbus_write_byte_data(client, ADP1653_REG_SW_STROBE,
ADP1653_REG_SW_STROBE_SW_STROBE);
if (rval)
return rval;
return i2c_smbus_write_byte_data(client, ADP1653_REG_SW_STROBE, 0);
}
/* --------------------------------------------------------------------------
* V4L2 controls
*/
static int adp1653_get_ctrl(struct v4l2_ctrl *ctrl)
{
struct adp1653_flash *flash =
container_of(ctrl->handler, struct adp1653_flash, ctrls);
int rval;
rval = adp1653_get_fault(flash);
if (rval)
return rval;
ctrl->cur.val = 0;
if (flash->fault & ADP1653_REG_FAULT_FLT_SCP)
ctrl->cur.val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
if (flash->fault & ADP1653_REG_FAULT_FLT_OT)
ctrl->cur.val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
if (flash->fault & ADP1653_REG_FAULT_FLT_TMR)
ctrl->cur.val |= V4L2_FLASH_FAULT_TIMEOUT;
if (flash->fault & ADP1653_REG_FAULT_FLT_OV)
ctrl->cur.val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;
flash->fault = 0;
return 0;
}
static int adp1653_set_ctrl(struct v4l2_ctrl *ctrl)
{
struct adp1653_flash *flash =
container_of(ctrl->handler, struct adp1653_flash, ctrls);
int rval;
rval = adp1653_get_fault(flash);
if (rval)
return rval;
if ((rval & (ADP1653_REG_FAULT_FLT_SCP |
ADP1653_REG_FAULT_FLT_OT |
ADP1653_REG_FAULT_FLT_OV)) &&
(ctrl->id == V4L2_CID_FLASH_STROBE ||
ctrl->id == V4L2_CID_FLASH_TORCH_INTENSITY ||
ctrl->id == V4L2_CID_FLASH_LED_MODE))
return -EBUSY;
switch (ctrl->id) {
case V4L2_CID_FLASH_STROBE:
return adp1653_strobe(flash, 1);
case V4L2_CID_FLASH_STROBE_STOP:
return adp1653_strobe(flash, 0);
}
return adp1653_update_hw(flash);
}
static const struct v4l2_ctrl_ops adp1653_ctrl_ops = {
.g_volatile_ctrl = adp1653_get_ctrl,
.s_ctrl = adp1653_set_ctrl,
};
static int adp1653_init_controls(struct adp1653_flash *flash)
{
struct v4l2_ctrl *fault;
v4l2_ctrl_handler_init(&flash->ctrls, 9);
flash->led_mode =
v4l2_ctrl_new_std_menu(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_LED_MODE,
V4L2_FLASH_LED_MODE_TORCH, ~0x7, 0);
v4l2_ctrl_new_std_menu(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_STROBE_SOURCE,
V4L2_FLASH_STROBE_SOURCE_SOFTWARE, ~0x1, 0);
v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);
flash->flash_timeout =
v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_TIMEOUT, TIMEOUT_MIN,
flash->platform_data->max_flash_timeout,
TIMEOUT_STEP,
flash->platform_data->max_flash_timeout);
flash->flash_intensity =
v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_INTENSITY,
ADP1653_FLASH_INTENSITY_MIN,
flash->platform_data->max_flash_intensity,
1, flash->platform_data->max_flash_intensity);
flash->torch_intensity =
v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_TORCH_INTENSITY,
ADP1653_TORCH_INTENSITY_MIN,
flash->platform_data->max_torch_intensity,
ADP1653_FLASH_INTENSITY_STEP,
flash->platform_data->max_torch_intensity);
flash->indicator_intensity =
v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_INDICATOR_INTENSITY,
ADP1653_INDICATOR_INTENSITY_MIN,
flash->platform_data->max_indicator_intensity,
ADP1653_INDICATOR_INTENSITY_STEP,
ADP1653_INDICATOR_INTENSITY_MIN);
fault = v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
V4L2_CID_FLASH_FAULT, 0,
V4L2_FLASH_FAULT_OVER_VOLTAGE
| V4L2_FLASH_FAULT_OVER_TEMPERATURE
| V4L2_FLASH_FAULT_SHORT_CIRCUIT, 0, 0);
if (flash->ctrls.error)
return flash->ctrls.error;
fault->flags |= V4L2_CTRL_FLAG_VOLATILE;
flash->subdev.ctrl_handler = &flash->ctrls;
return 0;
}
/* --------------------------------------------------------------------------
* V4L2 subdev operations
*/
static int
adp1653_init_device(struct adp1653_flash *flash)
{
struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
int rval;
/* Clear FAULT register by writing zero to OUT_SEL */
rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, 0);
if (rval < 0) {
dev_err(&client->dev, "failed writing fault register\n");
return -EIO;
}
mutex_lock(flash->ctrls.lock);
/* Reset faults before reading new ones. */
flash->fault = 0;
rval = adp1653_get_fault(flash);
mutex_unlock(flash->ctrls.lock);
if (rval > 0) {
dev_err(&client->dev, "faults detected: 0x%1.1x\n", rval);
return -EIO;
}
mutex_lock(flash->ctrls.lock);
rval = adp1653_update_hw(flash);
mutex_unlock(flash->ctrls.lock);
if (rval) {
dev_err(&client->dev,
"adp1653_update_hw failed at %s\n", __func__);
return -EIO;
}
return 0;
}
static int
__adp1653_set_power(struct adp1653_flash *flash, int on)
{
int ret;
if (flash->platform_data->power) {
ret = flash->platform_data->power(&flash->subdev, on);
if (ret < 0)
return ret;
} else {
gpiod_set_value(flash->platform_data->enable_gpio, on);
if (on)
/* Some delay is apparently required. */
udelay(20);
}
if (!on)
return 0;
ret = adp1653_init_device(flash);
if (ret >= 0)
return ret;
if (flash->platform_data->power)
flash->platform_data->power(&flash->subdev, 0);
else
gpiod_set_value(flash->platform_data->enable_gpio, 0);
return ret;
}
static int
adp1653_set_power(struct v4l2_subdev *subdev, int on)
{
struct adp1653_flash *flash = to_adp1653_flash(subdev);
int ret = 0;
mutex_lock(&flash->power_lock);
/* If the power count is modified from 0 to != 0 or from != 0 to 0,
* update the power state.
*/
if (flash->power_count == !on) {
ret = __adp1653_set_power(flash, !!on);
if (ret < 0)
goto done;
}
/* Update the power count. */
flash->power_count += on ? 1 : -1;
WARN_ON(flash->power_count < 0);
done:
mutex_unlock(&flash->power_lock);
return ret;
}
static int adp1653_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
return adp1653_set_power(sd, 1);
}
static int adp1653_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
{
return adp1653_set_power(sd, 0);
}
static const struct v4l2_subdev_core_ops adp1653_core_ops = {
.s_power = adp1653_set_power,
};
static const struct v4l2_subdev_ops adp1653_ops = {
.core = &adp1653_core_ops,
};
static const struct v4l2_subdev_internal_ops adp1653_internal_ops = {
.open = adp1653_open,
.close = adp1653_close,
};
/* --------------------------------------------------------------------------
* I2C driver
*/
#ifdef CONFIG_PM
static int adp1653_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct v4l2_subdev *subdev = i2c_get_clientdata(client);
struct adp1653_flash *flash = to_adp1653_flash(subdev);
if (!flash->power_count)
return 0;
return __adp1653_set_power(flash, 0);
}
static int adp1653_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct v4l2_subdev *subdev = i2c_get_clientdata(client);
struct adp1653_flash *flash = to_adp1653_flash(subdev);
if (!flash->power_count)
return 0;
return __adp1653_set_power(flash, 1);
}
#else
#define adp1653_suspend NULL
#define adp1653_resume NULL
#endif /* CONFIG_PM */
static int adp1653_of_init(struct i2c_client *client,
struct adp1653_flash *flash,
struct device_node *node)
{
struct adp1653_platform_data *pd;
struct device_node *child;
pd = devm_kzalloc(&client->dev, sizeof(*pd), GFP_KERNEL);
if (!pd)
return -ENOMEM;
flash->platform_data = pd;
child = of_get_child_by_name(node, "flash");
if (!child)
return -EINVAL;
if (of_property_read_u32(child, "flash-timeout-us",
&pd->max_flash_timeout))
goto err;
if (of_property_read_u32(child, "flash-max-microamp",
&pd->max_flash_intensity))
goto err;
pd->max_flash_intensity /= 1000;
if (of_property_read_u32(child, "led-max-microamp",
&pd->max_torch_intensity))
goto err;
pd->max_torch_intensity /= 1000;
of_node_put(child);
child = of_get_child_by_name(node, "indicator");
if (!child)
return -EINVAL;
if (of_property_read_u32(child, "led-max-microamp",
&pd->max_indicator_intensity))
goto err;
of_node_put(child);
pd->enable_gpio = devm_gpiod_get(&client->dev, "enable", GPIOD_OUT_LOW);
if (IS_ERR(pd->enable_gpio)) {
dev_err(&client->dev, "Error getting GPIO\n");
return PTR_ERR(pd->enable_gpio);
}
return 0;
err:
dev_err(&client->dev, "Required property not found\n");
of_node_put(child);
return -EINVAL;
}
static int adp1653_probe(struct i2c_client *client,
const struct i2c_device_id *devid)
{
struct adp1653_flash *flash;
int ret;
flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
if (flash == NULL)
return -ENOMEM;
if (client->dev.of_node) {
ret = adp1653_of_init(client, flash, client->dev.of_node);
if (ret)
return ret;
} else {
if (!client->dev.platform_data) {
dev_err(&client->dev,
"Neither DT not platform data provided\n");
return -EINVAL;
}
flash->platform_data = client->dev.platform_data;
}
mutex_init(&flash->power_lock);
v4l2_i2c_subdev_init(&flash->subdev, client, &adp1653_ops);
flash->subdev.internal_ops = &adp1653_internal_ops;
flash->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
ret = adp1653_init_controls(flash);
if (ret)
goto free_and_quit;
ret = media_entity_pads_init(&flash->subdev.entity, 0, NULL);
if (ret < 0)
goto free_and_quit;
flash->subdev.entity.function = MEDIA_ENT_F_FLASH;
return 0;
free_and_quit:
dev_err(&client->dev, "adp1653: failed to register device\n");
v4l2_ctrl_handler_free(&flash->ctrls);
return ret;
}
static int adp1653_remove(struct i2c_client *client)
{
struct v4l2_subdev *subdev = i2c_get_clientdata(client);
struct adp1653_flash *flash = to_adp1653_flash(subdev);
v4l2_device_unregister_subdev(&flash->subdev);
v4l2_ctrl_handler_free(&flash->ctrls);
media_entity_cleanup(&flash->subdev.entity);
return 0;
}
static const struct i2c_device_id adp1653_id_table[] = {
{ ADP1653_NAME, 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, adp1653_id_table);
static const struct dev_pm_ops adp1653_pm_ops = {
.suspend = adp1653_suspend,
.resume = adp1653_resume,
};
static struct i2c_driver adp1653_i2c_driver = {
.driver = {
.name = ADP1653_NAME,
.pm = &adp1653_pm_ops,
},
.probe = adp1653_probe,
.remove = adp1653_remove,
.id_table = adp1653_id_table,
};
module_i2c_driver(adp1653_i2c_driver);
MODULE_AUTHOR("Sakari Ailus <sakari.ailus@nokia.com>");
MODULE_DESCRIPTION("Analog Devices ADP1653 LED flash driver");
MODULE_LICENSE("GPL");
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