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@@ -1,149 +0,0 @@
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-#include <linux/kernel.h>
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-#include <linux/platform_device.h>
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-#include <linux/leds.h>
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-#include <linux/io.h>
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-#include <linux/atmel_pwm.h>
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-#include <linux/slab.h>
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-#include <linux/module.h>
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-
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-
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-struct pwmled {
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- struct led_classdev cdev;
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- struct pwm_channel pwmc;
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- struct gpio_led *desc;
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- u32 mult;
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- u8 active_low;
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-};
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-
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-
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-/*
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- * For simplicity, we use "brightness" as if it were a linear function
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- * of PWM duty cycle. However, a logarithmic function of duty cycle is
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- * probably a better match for perceived brightness: two is half as bright
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- * as four, four is half as bright as eight, etc
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- */
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-static void pwmled_brightness(struct led_classdev *cdev, enum led_brightness b)
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-{
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- struct pwmled *led;
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-
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- /* update the duty cycle for the *next* period */
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- led = container_of(cdev, struct pwmled, cdev);
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- pwm_channel_writel(&led->pwmc, PWM_CUPD, led->mult * (unsigned) b);
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-}
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-
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-/*
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- * NOTE: we reuse the platform_data structure of GPIO leds,
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- * but repurpose its "gpio" number as a PWM channel number.
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- */
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-static int pwmled_probe(struct platform_device *pdev)
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-{
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- const struct gpio_led_platform_data *pdata;
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- struct pwmled *leds;
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- int i;
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- int status;
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-
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- pdata = dev_get_platdata(&pdev->dev);
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- if (!pdata || pdata->num_leds < 1)
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- return -ENODEV;
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-
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- leds = devm_kzalloc(&pdev->dev, pdata->num_leds * sizeof(*leds),
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- GFP_KERNEL);
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- if (!leds)
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- return -ENOMEM;
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-
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- for (i = 0; i < pdata->num_leds; i++) {
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- struct pwmled *led = leds + i;
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- const struct gpio_led *dat = pdata->leds + i;
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- u32 tmp;
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-
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- led->cdev.name = dat->name;
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- led->cdev.brightness = LED_OFF;
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- led->cdev.brightness_set = pwmled_brightness;
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- led->cdev.default_trigger = dat->default_trigger;
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-
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- led->active_low = dat->active_low;
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-
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- status = pwm_channel_alloc(dat->gpio, &led->pwmc);
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- if (status < 0)
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- goto err;
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-
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- /*
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- * Prescale clock by 2^x, so PWM counts in low MHz.
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- * Start each cycle with the LED active, so increasing
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- * the duty cycle gives us more time on (== brighter).
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- */
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- tmp = 5;
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- if (!led->active_low)
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- tmp |= PWM_CPR_CPOL;
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- pwm_channel_writel(&led->pwmc, PWM_CMR, tmp);
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-
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- /*
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- * Pick a period so PWM cycles at 100+ Hz; and a multiplier
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- * for scaling duty cycle: brightness * mult.
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- */
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- tmp = (led->pwmc.mck / (1 << 5)) / 100;
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- tmp /= 255;
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- led->mult = tmp;
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- pwm_channel_writel(&led->pwmc, PWM_CDTY,
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- led->cdev.brightness * 255);
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- pwm_channel_writel(&led->pwmc, PWM_CPRD,
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- LED_FULL * tmp);
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-
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- pwm_channel_enable(&led->pwmc);
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-
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- /* Hand it over to the LED framework */
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- status = led_classdev_register(&pdev->dev, &led->cdev);
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- if (status < 0) {
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- pwm_channel_free(&led->pwmc);
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- goto err;
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- }
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- }
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-
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- platform_set_drvdata(pdev, leds);
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- return 0;
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-
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-err:
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- if (i > 0) {
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- for (i = i - 1; i >= 0; i--) {
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- led_classdev_unregister(&leds[i].cdev);
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- pwm_channel_free(&leds[i].pwmc);
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- }
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- }
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-
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- return status;
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-}
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-
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-static int pwmled_remove(struct platform_device *pdev)
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-{
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- const struct gpio_led_platform_data *pdata;
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- struct pwmled *leds;
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- unsigned i;
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-
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- pdata = dev_get_platdata(&pdev->dev);
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- leds = platform_get_drvdata(pdev);
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-
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- for (i = 0; i < pdata->num_leds; i++) {
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- struct pwmled *led = leds + i;
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-
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- led_classdev_unregister(&led->cdev);
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- pwm_channel_free(&led->pwmc);
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- }
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-
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- return 0;
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-}
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-
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-static struct platform_driver pwmled_driver = {
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- .driver = {
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- .name = "leds-atmel-pwm",
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- .owner = THIS_MODULE,
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- },
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- /* REVISIT add suspend() and resume() methods */
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- .probe = pwmled_probe,
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- .remove = pwmled_remove,
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-};
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-
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-module_platform_driver(pwmled_driver);
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-
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-MODULE_DESCRIPTION("Driver for LEDs with PWM-controlled brightness");
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-MODULE_LICENSE("GPL");
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-MODULE_ALIAS("platform:leds-atmel-pwm");
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