Commit 3088883b authored by Alexandre Belloni's avatar Alexandre Belloni Committed by Nicolas Ferre

leds: atmel-pwm: remove obsolete driver

The leds-atmel-pwm driver is now obsolete. It is not used by any mainlined
boards and is replaced by the generic leds_pwm with the pwm-atmel driver using
the generic PWM framework.
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: default avatarBryan Wu <cooloney@gmail.com>
Signed-off-by: default avatarNicolas Ferre <nicolas.ferre@atmel.com>
parent ec38846a
......@@ -32,14 +32,6 @@ config LEDS_88PM860X
This option enables support for on-chip LED drivers found on Marvell
Semiconductor 88PM8606 PMIC.
config LEDS_ATMEL_PWM
tristate "LED Support using Atmel PWM outputs"
depends on LEDS_CLASS
depends on ATMEL_PWM
help
This option enables support for LEDs driven using outputs
of the dedicated PWM controller found on newer Atmel SOCs.
config LEDS_LM3530
tristate "LCD Backlight driver for LM3530"
depends on LEDS_CLASS
......
......@@ -6,7 +6,6 @@ obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o
# LED Platform Drivers
obj-$(CONFIG_LEDS_88PM860X) += leds-88pm860x.o
obj-$(CONFIG_LEDS_ATMEL_PWM) += leds-atmel-pwm.o
obj-$(CONFIG_LEDS_BD2802) += leds-bd2802.o
obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o
obj-$(CONFIG_LEDS_LM3530) += leds-lm3530.o
......
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/leds.h>
#include <linux/io.h>
#include <linux/atmel_pwm.h>
#include <linux/slab.h>
#include <linux/module.h>
struct pwmled {
struct led_classdev cdev;
struct pwm_channel pwmc;
struct gpio_led *desc;
u32 mult;
u8 active_low;
};
/*
* For simplicity, we use "brightness" as if it were a linear function
* of PWM duty cycle. However, a logarithmic function of duty cycle is
* probably a better match for perceived brightness: two is half as bright
* as four, four is half as bright as eight, etc
*/
static void pwmled_brightness(struct led_classdev *cdev, enum led_brightness b)
{
struct pwmled *led;
/* update the duty cycle for the *next* period */
led = container_of(cdev, struct pwmled, cdev);
pwm_channel_writel(&led->pwmc, PWM_CUPD, led->mult * (unsigned) b);
}
/*
* NOTE: we reuse the platform_data structure of GPIO leds,
* but repurpose its "gpio" number as a PWM channel number.
*/
static int pwmled_probe(struct platform_device *pdev)
{
const struct gpio_led_platform_data *pdata;
struct pwmled *leds;
int i;
int status;
pdata = dev_get_platdata(&pdev->dev);
if (!pdata || pdata->num_leds < 1)
return -ENODEV;
leds = devm_kzalloc(&pdev->dev, pdata->num_leds * sizeof(*leds),
GFP_KERNEL);
if (!leds)
return -ENOMEM;
for (i = 0; i < pdata->num_leds; i++) {
struct pwmled *led = leds + i;
const struct gpio_led *dat = pdata->leds + i;
u32 tmp;
led->cdev.name = dat->name;
led->cdev.brightness = LED_OFF;
led->cdev.brightness_set = pwmled_brightness;
led->cdev.default_trigger = dat->default_trigger;
led->active_low = dat->active_low;
status = pwm_channel_alloc(dat->gpio, &led->pwmc);
if (status < 0)
goto err;
/*
* Prescale clock by 2^x, so PWM counts in low MHz.
* Start each cycle with the LED active, so increasing
* the duty cycle gives us more time on (== brighter).
*/
tmp = 5;
if (!led->active_low)
tmp |= PWM_CPR_CPOL;
pwm_channel_writel(&led->pwmc, PWM_CMR, tmp);
/*
* Pick a period so PWM cycles at 100+ Hz; and a multiplier
* for scaling duty cycle: brightness * mult.
*/
tmp = (led->pwmc.mck / (1 << 5)) / 100;
tmp /= 255;
led->mult = tmp;
pwm_channel_writel(&led->pwmc, PWM_CDTY,
led->cdev.brightness * 255);
pwm_channel_writel(&led->pwmc, PWM_CPRD,
LED_FULL * tmp);
pwm_channel_enable(&led->pwmc);
/* Hand it over to the LED framework */
status = led_classdev_register(&pdev->dev, &led->cdev);
if (status < 0) {
pwm_channel_free(&led->pwmc);
goto err;
}
}
platform_set_drvdata(pdev, leds);
return 0;
err:
if (i > 0) {
for (i = i - 1; i >= 0; i--) {
led_classdev_unregister(&leds[i].cdev);
pwm_channel_free(&leds[i].pwmc);
}
}
return status;
}
static int pwmled_remove(struct platform_device *pdev)
{
const struct gpio_led_platform_data *pdata;
struct pwmled *leds;
unsigned i;
pdata = dev_get_platdata(&pdev->dev);
leds = platform_get_drvdata(pdev);
for (i = 0; i < pdata->num_leds; i++) {
struct pwmled *led = leds + i;
led_classdev_unregister(&led->cdev);
pwm_channel_free(&led->pwmc);
}
return 0;
}
static struct platform_driver pwmled_driver = {
.driver = {
.name = "leds-atmel-pwm",
.owner = THIS_MODULE,
},
/* REVISIT add suspend() and resume() methods */
.probe = pwmled_probe,
.remove = pwmled_remove,
};
module_platform_driver(pwmled_driver);
MODULE_DESCRIPTION("Driver for LEDs with PWM-controlled brightness");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:leds-atmel-pwm");
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