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authorAlexandre Belloni <alexandre.belloni@free-electrons.com>2014-05-29 01:20:17 +0200
committerNicolas Ferre <nicolas.ferre@atmel.com>2014-07-09 15:13:35 +0200
commit3088883b598be8adc47ba5330f3492331d7c6ec5 (patch)
tree89dd9e8b1dd47a351d6b13b6000432ede2b352c0 /drivers/leds/leds-atmel-pwm.c
parentbacklight: atmel-pwm-bl: remove obsolete driver (diff)
downloadlinux-3088883b598be8adc47ba5330f3492331d7c6ec5.tar.xz
linux-3088883b598be8adc47ba5330f3492331d7c6ec5.zip
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: Alexandre Belloni <alexandre.belloni@free-electrons.com> Acked-by: Bryan Wu <cooloney@gmail.com> Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Diffstat (limited to 'drivers/leds/leds-atmel-pwm.c')
-rw-r--r--drivers/leds/leds-atmel-pwm.c149
1 files changed, 0 insertions, 149 deletions
diff --git a/drivers/leds/leds-atmel-pwm.c b/drivers/leds/leds-atmel-pwm.c
deleted file mode 100644
index 56cec8d6a2ac..000000000000
--- a/drivers/leds/leds-atmel-pwm.c
+++ /dev/null
@@ -1,149 +0,0 @@
-#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");