Merge branch 'for-rc-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/pavel/linux-leds

Pull LED fixes from Pavel Machek:
 "This pull is due to 'leds: trigger: fix potential deadlock with
  libata' -- people find the warn annoying.

  It also contains new driver and two trivial fixes"

* 'for-rc-5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/pavel/linux-leds:
  leds: rt8515: Add Richtek RT8515 LED driver
  dt-bindings: leds: Add DT binding for Richtek RT8515
  leds: trigger: fix potential deadlock with libata
  leds: leds-ariel: convert comma to semicolon
  leds: leds-lm3533: convert comma to semicolon
This commit is contained in:
Linus Torvalds 2021-01-31 11:23:35 -08:00
commit 29bd2d2100
9 changed files with 542 additions and 8 deletions

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@ -0,0 +1,111 @@
# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/leds/richtek,rt8515.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: Richtek RT8515 1.5A dual channel LED driver
maintainers:
- Linus Walleij <linus.walleij@linaro.org>
description: |
The Richtek RT8515 is a dual channel (two mode) LED driver that
supports driving a white LED in flash or torch mode. The maximum
current for each mode is defined in hardware using two resistors
RFS and RTS.
properties:
compatible:
const: richtek,rt8515
enf-gpios:
maxItems: 1
description: A connection to the 'ENF' (enable flash) pin.
ent-gpios:
maxItems: 1
description: A connection to the 'ENT' (enable torch) pin.
richtek,rfs-ohms:
minimum: 7680
maximum: 367000
description: The resistance value of the RFS resistor. This
resistors limits the maximum flash current. This must be set
for the property flash-max-microamp to work, the RFS resistor
defines the range of the dimmer setting (brightness) of the
flash LED.
richtek,rts-ohms:
minimum: 7680
maximum: 367000
description: The resistance value of the RTS resistor. This
resistors limits the maximum torch current. This must be set
for the property torch-max-microamp to work, the RTS resistor
defines the range of the dimmer setting (brightness) of the
torch LED.
led:
type: object
$ref: common.yaml#
properties:
function: true
color: true
flash-max-timeout-us: true
flash-max-microamp:
maximum: 700000
description: The maximum current for flash mode
is hardwired to the component using the RFS resistor to
ground. The maximum hardware current setting is calculated
according to the formula Imax = 5500 / RFS. The lowest
allowed resistance value is 7.86 kOhm giving an absolute
maximum current of 700mA. By setting this attribute in
the device tree, you can further restrict the maximum
current below the hardware limit. This requires the RFS
to be defined as it defines the maximum range.
led-max-microamp:
maximum: 700000
description: The maximum current for torch mode
is hardwired to the component using the RTS resistor to
ground. The maximum hardware current setting is calculated
according to the formula Imax = 5500 / RTS. The lowest
allowed resistance value is 7.86 kOhm giving an absolute
maximum current of 700mA. By setting this attribute in
the device tree, you can further restrict the maximum
current below the hardware limit. This requires the RTS
to be defined as it defines the maximum range.
additionalProperties: false
required:
- compatible
- ent-gpios
- enf-gpios
- led
additionalProperties: false
examples:
- |
#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/leds/common.h>
led-controller {
compatible = "richtek,rt8515";
enf-gpios = <&gpio4 12 GPIO_ACTIVE_HIGH>;
ent-gpios = <&gpio4 13 GPIO_ACTIVE_HIGH>;
richtek,rfs-ohms = <16000>;
richtek,rts-ohms = <100000>;
led {
function = LED_FUNCTION_FLASH;
color = <LED_COLOR_ID_WHITE>;
flash-max-timeout-us = <250000>;
flash-max-microamp = <150000>;
led-max-microamp = <25000>;
};
};
...

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@ -928,6 +928,9 @@ config LEDS_ACER_A500
This option enables support for the Power Button LED of
Acer Iconia Tab A500.
comment "Flash and Torch LED drivers"
source "drivers/leds/flash/Kconfig"
comment "LED Triggers"
source "drivers/leds/trigger/Kconfig"

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@ -103,5 +103,8 @@ obj-$(CONFIG_LEDS_SPI_BYTE) += leds-spi-byte.o
# LED Userspace Drivers
obj-$(CONFIG_LEDS_USER) += uleds.o
# Flash and Torch LED Drivers
obj-$(CONFIG_LEDS_CLASS_FLASH) += flash/
# LED Triggers
obj-$(CONFIG_LEDS_TRIGGERS) += trigger/

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@ -0,0 +1,15 @@
# SPDX-License-Identifier: GPL-2.0
if LEDS_CLASS_FLASH
config LEDS_RT8515
tristate "LED support for Richtek RT8515 flash/torch LED"
depends on GPIOLIB
help
This option enables support for the Richtek RT8515 flash
and torch LEDs found on some mobile phones.
To compile this driver as a module, choose M here: the module
will be called leds-rt8515.
endif # LEDS_CLASS_FLASH

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@ -0,0 +1,3 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_LEDS_RT8515) += leds-rt8515.o

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@ -0,0 +1,397 @@
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* LED driver for Richtek RT8515 flash/torch white LEDs
* found on some Samsung mobile phones.
*
* This is a 1.5A Boost dual channel driver produced around 2011.
*
* The component lacks a datasheet, but in the schematic picture
* from the LG P970 service manual you can see the connections
* from the RT8515 to the LED, with two resistors connected
* from the pins "RFS" and "RTS" to ground.
*
* On the LG P970:
* RFS (resistance flash setting?) is 20 kOhm
* RTS (resistance torch setting?) is 39 kOhm
*
* Some sleuthing finds us the RT9387A which we have a datasheet for:
* https://static5.arrow.com/pdfs/2014/7/27/8/21/12/794/rtt_/manual/94download_ds.jspprt9387a.jspprt9387a.pdf
* This apparently works the same way so in theory this driver
* should cover RT9387A as well. This has not been tested, please
* update the compatibles if you add RT9387A support.
*
* Linus Walleij <linus.walleij@linaro.org>
*/
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/led-class-flash.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regulator/consumer.h>
#include <media/v4l2-flash-led-class.h>
/* We can provide 15-700 mA out to the LED */
#define RT8515_MIN_IOUT_MA 15
#define RT8515_MAX_IOUT_MA 700
/* The maximum intensity is 1-16 for flash and 1-100 for torch */
#define RT8515_FLASH_MAX 16
#define RT8515_TORCH_MAX 100
#define RT8515_TIMEOUT_US 250000U
#define RT8515_MAX_TIMEOUT_US 300000U
struct rt8515 {
struct led_classdev_flash fled;
struct device *dev;
struct v4l2_flash *v4l2_flash;
struct mutex lock;
struct regulator *reg;
struct gpio_desc *enable_torch;
struct gpio_desc *enable_flash;
struct timer_list powerdown_timer;
u32 max_timeout; /* Flash max timeout */
int flash_max_intensity;
int torch_max_intensity;
};
static struct rt8515 *to_rt8515(struct led_classdev_flash *fled)
{
return container_of(fled, struct rt8515, fled);
}
static void rt8515_gpio_led_off(struct rt8515 *rt)
{
gpiod_set_value(rt->enable_flash, 0);
gpiod_set_value(rt->enable_torch, 0);
}
static void rt8515_gpio_brightness_commit(struct gpio_desc *gpiod,
int brightness)
{
int i;
/*
* Toggling a GPIO line with a small delay increases the
* brightness one step at a time.
*/
for (i = 0; i < brightness; i++) {
gpiod_set_value(gpiod, 0);
udelay(1);
gpiod_set_value(gpiod, 1);
udelay(1);
}
}
/* This is setting the torch light level */
static int rt8515_led_brightness_set(struct led_classdev *led,
enum led_brightness brightness)
{
struct led_classdev_flash *fled = lcdev_to_flcdev(led);
struct rt8515 *rt = to_rt8515(fled);
mutex_lock(&rt->lock);
if (brightness == LED_OFF) {
/* Off */
rt8515_gpio_led_off(rt);
} else if (brightness < RT8515_TORCH_MAX) {
/* Step it up to movie mode brightness using the flash pin */
rt8515_gpio_brightness_commit(rt->enable_torch, brightness);
} else {
/* Max torch brightness requested */
gpiod_set_value(rt->enable_torch, 1);
}
mutex_unlock(&rt->lock);
return 0;
}
static int rt8515_led_flash_strobe_set(struct led_classdev_flash *fled,
bool state)
{
struct rt8515 *rt = to_rt8515(fled);
struct led_flash_setting *timeout = &fled->timeout;
int brightness = rt->flash_max_intensity;
mutex_lock(&rt->lock);
if (state) {
/* Enable LED flash mode and set brightness */
rt8515_gpio_brightness_commit(rt->enable_flash, brightness);
/* Set timeout */
mod_timer(&rt->powerdown_timer,
jiffies + usecs_to_jiffies(timeout->val));
} else {
del_timer_sync(&rt->powerdown_timer);
/* Turn the LED off */
rt8515_gpio_led_off(rt);
}
fled->led_cdev.brightness = LED_OFF;
/* After this the torch LED will be disabled */
mutex_unlock(&rt->lock);
return 0;
}
static int rt8515_led_flash_strobe_get(struct led_classdev_flash *fled,
bool *state)
{
struct rt8515 *rt = to_rt8515(fled);
*state = timer_pending(&rt->powerdown_timer);
return 0;
}
static int rt8515_led_flash_timeout_set(struct led_classdev_flash *fled,
u32 timeout)
{
/* The timeout is stored in the led-class-flash core */
return 0;
}
static const struct led_flash_ops rt8515_flash_ops = {
.strobe_set = rt8515_led_flash_strobe_set,
.strobe_get = rt8515_led_flash_strobe_get,
.timeout_set = rt8515_led_flash_timeout_set,
};
static void rt8515_powerdown_timer(struct timer_list *t)
{
struct rt8515 *rt = from_timer(rt, t, powerdown_timer);
/* Turn the LED off */
rt8515_gpio_led_off(rt);
}
static void rt8515_init_flash_timeout(struct rt8515 *rt)
{
struct led_classdev_flash *fled = &rt->fled;
struct led_flash_setting *s;
/* Init flash timeout setting */
s = &fled->timeout;
s->min = 1;
s->max = rt->max_timeout;
s->step = 1;
/*
* Set default timeout to RT8515_TIMEOUT_US except if
* max_timeout from DT is lower.
*/
s->val = min(rt->max_timeout, RT8515_TIMEOUT_US);
}
#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS)
/* Configure the V2L2 flash subdevice */
static void rt8515_init_v4l2_flash_config(struct rt8515 *rt,
struct v4l2_flash_config *v4l2_sd_cfg)
{
struct led_classdev *led = &rt->fled.led_cdev;
struct led_flash_setting *s;
strscpy(v4l2_sd_cfg->dev_name, led->dev->kobj.name,
sizeof(v4l2_sd_cfg->dev_name));
/*
* Init flash intensity setting: this is a linear scale
* capped from the device tree max intensity setting
* 1..flash_max_intensity
*/
s = &v4l2_sd_cfg->intensity;
s->min = 1;
s->max = rt->flash_max_intensity;
s->step = 1;
s->val = s->max;
}
static void rt8515_v4l2_flash_release(struct rt8515 *rt)
{
v4l2_flash_release(rt->v4l2_flash);
}
#else
static void rt8515_init_v4l2_flash_config(struct rt8515 *rt,
struct v4l2_flash_config *v4l2_sd_cfg)
{
}
static void rt8515_v4l2_flash_release(struct rt8515 *rt)
{
}
#endif
static void rt8515_determine_max_intensity(struct rt8515 *rt,
struct fwnode_handle *led,
const char *resistance,
const char *max_ua_prop, int hw_max,
int *max_intensity_setting)
{
u32 res = 0; /* Can't be 0 so 0 is undefined */
u32 ua;
u32 max_ma;
int max_intensity;
int ret;
fwnode_property_read_u32(rt->dev->fwnode, resistance, &res);
ret = fwnode_property_read_u32(led, max_ua_prop, &ua);
/* Missing info in DT, OK go with hardware maxima */
if (ret || res == 0) {
dev_err(rt->dev,
"either %s or %s missing from DT, using HW max\n",
resistance, max_ua_prop);
max_ma = RT8515_MAX_IOUT_MA;
max_intensity = hw_max;
goto out_assign_max;
}
/*
* Formula from the datasheet, this is the maximum current
* defined by the hardware.
*/
max_ma = (5500 * 1000) / res;
/*
* Calculate max intensity (linear scaling)
* Formula is ((ua / 1000) / max_ma) * 100, then simplified
*/
max_intensity = (ua / 10) / max_ma;
dev_info(rt->dev,
"current restricted from %u to %u mA, max intensity %d/100\n",
max_ma, (ua / 1000), max_intensity);
out_assign_max:
dev_info(rt->dev, "max intensity %d/%d = %d mA\n",
max_intensity, hw_max, max_ma);
*max_intensity_setting = max_intensity;
}
static int rt8515_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct fwnode_handle *child;
struct rt8515 *rt;
struct led_classdev *led;
struct led_classdev_flash *fled;
struct led_init_data init_data = {};
struct v4l2_flash_config v4l2_sd_cfg = {};
int ret;
rt = devm_kzalloc(dev, sizeof(*rt), GFP_KERNEL);
if (!rt)
return -ENOMEM;
rt->dev = dev;
fled = &rt->fled;
led = &fled->led_cdev;
/* ENF - Enable Flash line */
rt->enable_flash = devm_gpiod_get(dev, "enf", GPIOD_OUT_LOW);
if (IS_ERR(rt->enable_flash))
return dev_err_probe(dev, PTR_ERR(rt->enable_flash),
"cannot get ENF (enable flash) GPIO\n");
/* ENT - Enable Torch line */
rt->enable_torch = devm_gpiod_get(dev, "ent", GPIOD_OUT_LOW);
if (IS_ERR(rt->enable_torch))
return dev_err_probe(dev, PTR_ERR(rt->enable_torch),
"cannot get ENT (enable torch) GPIO\n");
child = fwnode_get_next_available_child_node(dev->fwnode, NULL);
if (!child) {
dev_err(dev,
"No fwnode child node found for connected LED.\n");
return -EINVAL;
}
init_data.fwnode = child;
rt8515_determine_max_intensity(rt, child, "richtek,rfs-ohms",
"flash-max-microamp",
RT8515_FLASH_MAX,
&rt->flash_max_intensity);
rt8515_determine_max_intensity(rt, child, "richtek,rts-ohms",
"led-max-microamp",
RT8515_TORCH_MAX,
&rt->torch_max_intensity);
ret = fwnode_property_read_u32(child, "flash-max-timeout-us",
&rt->max_timeout);
if (ret) {
rt->max_timeout = RT8515_MAX_TIMEOUT_US;
dev_warn(dev,
"flash-max-timeout-us property missing\n");
}
timer_setup(&rt->powerdown_timer, rt8515_powerdown_timer, 0);
rt8515_init_flash_timeout(rt);
fled->ops = &rt8515_flash_ops;
led->max_brightness = rt->torch_max_intensity;
led->brightness_set_blocking = rt8515_led_brightness_set;
led->flags |= LED_CORE_SUSPENDRESUME | LED_DEV_CAP_FLASH;
mutex_init(&rt->lock);
platform_set_drvdata(pdev, rt);
ret = devm_led_classdev_flash_register_ext(dev, fled, &init_data);
if (ret) {
dev_err(dev, "can't register LED %s\n", led->name);
mutex_destroy(&rt->lock);
return ret;
}
rt8515_init_v4l2_flash_config(rt, &v4l2_sd_cfg);
/* Create a V4L2 Flash device if V4L2 flash is enabled */
rt->v4l2_flash = v4l2_flash_init(dev, child, fled, NULL, &v4l2_sd_cfg);
if (IS_ERR(rt->v4l2_flash)) {
ret = PTR_ERR(rt->v4l2_flash);
dev_err(dev, "failed to register V4L2 flash device (%d)\n",
ret);
/*
* Continue without the V4L2 flash
* (we still have the classdev)
*/
}
return 0;
}
static int rt8515_remove(struct platform_device *pdev)
{
struct rt8515 *rt = platform_get_drvdata(pdev);
rt8515_v4l2_flash_release(rt);
del_timer_sync(&rt->powerdown_timer);
mutex_destroy(&rt->lock);
return 0;
}
static const struct of_device_id rt8515_match[] = {
{ .compatible = "richtek,rt8515", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, rt8515_match);
static struct platform_driver rt8515_driver = {
.driver = {
.name = "rt8515",
.of_match_table = rt8515_match,
},
.probe = rt8515_probe,
.remove = rt8515_remove,
};
module_platform_driver(rt8515_driver);
MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
MODULE_DESCRIPTION("Richtek RT8515 LED driver");
MODULE_LICENSE("GPL");

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@ -378,14 +378,15 @@ void led_trigger_event(struct led_trigger *trig,
enum led_brightness brightness)
{
struct led_classdev *led_cdev;
unsigned long flags;
if (!trig)
return;
read_lock(&trig->leddev_list_lock);
read_lock_irqsave(&trig->leddev_list_lock, flags);
list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list)
led_set_brightness(led_cdev, brightness);
read_unlock(&trig->leddev_list_lock);
read_unlock_irqrestore(&trig->leddev_list_lock, flags);
}
EXPORT_SYMBOL_GPL(led_trigger_event);
@ -396,11 +397,12 @@ static void led_trigger_blink_setup(struct led_trigger *trig,
int invert)
{
struct led_classdev *led_cdev;
unsigned long flags;
if (!trig)
return;
read_lock(&trig->leddev_list_lock);
read_lock_irqsave(&trig->leddev_list_lock, flags);
list_for_each_entry(led_cdev, &trig->led_cdevs, trig_list) {
if (oneshot)
led_blink_set_oneshot(led_cdev, delay_on, delay_off,
@ -408,7 +410,7 @@ static void led_trigger_blink_setup(struct led_trigger *trig,
else
led_blink_set(led_cdev, delay_on, delay_off);
}
read_unlock(&trig->leddev_list_lock);
read_unlock_irqrestore(&trig->leddev_list_lock, flags);
}
void led_trigger_blink(struct led_trigger *trig,

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@ -96,14 +96,14 @@ static int ariel_led_probe(struct platform_device *pdev)
return -ENOMEM;
leds[0].ec_index = EC_BLUE_LED;
leds[0].led_cdev.name = "blue:power",
leds[0].led_cdev.name = "blue:power";
leds[0].led_cdev.default_trigger = "default-on";
leds[1].ec_index = EC_AMBER_LED;
leds[1].led_cdev.name = "amber:status",
leds[1].led_cdev.name = "amber:status";
leds[2].ec_index = EC_GREEN_LED;
leds[2].led_cdev.name = "green:status",
leds[2].led_cdev.name = "green:status";
leds[2].led_cdev.default_trigger = "default-on";
for (i = 0; i < NLEDS; i++) {

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@ -679,7 +679,7 @@ static int lm3533_led_probe(struct platform_device *pdev)
led->cdev.brightness_get = lm3533_led_get;
led->cdev.blink_set = lm3533_led_blink_set;
led->cdev.brightness = LED_OFF;
led->cdev.groups = lm3533_led_attribute_groups,
led->cdev.groups = lm3533_led_attribute_groups;
led->id = pdev->id;
mutex_init(&led->mutex);