--- /dev/null
+/*
+ * TWL4030 PWM controlled LED driver (LEDA, LEDB, PWM0, PWM1)
+ *
+ * Author: Gražvydas Ignotas <notasas@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/workqueue.h>
+#include <linux/platform_device.h>
+#include <linux/leds.h>
+#include <linux/leds_pwm.h>
+#include <linux/i2c/twl.h>
+#include <linux/slab.h>
+
+#define TWL_INTBR_GPBR1 0x0c
+#define TWL_INTBR_PMBR1 0x0d
+
+#define TWL4030_PWMx_PWMxON 0x00
+#define TWL4030_PWMx_PWMxOFF 0x01
+#define TWL4030_LED_LEDEN 0x00
+
+#define GPBR1_PWM0_CLK_ENABLE BIT(0)
+#define GPBR1_PWM1_CLK_ENABLE BIT(1)
+#define GPBR1_PWM0_ENABLE BIT(2)
+#define GPBR1_PWM1_ENABLE BIT(3)
+
+/* LEDEN bits */
+#define LEDEN_LEDAON BIT(0)
+#define LEDEN_LEDBON BIT(1)
+#define LEDEN_LEDAPWM BIT(4)
+#define LEDEN_LEDBPWM BIT(5)
+
+enum twl4030_led {
+ TWL4030_LEDA = 0,
+ TWL4030_LEDB,
+ TWL4030_PWM0,
+ TWL4030_PWM1,
+};
+
+struct twl4030_pwmled {
+ struct led_classdev cdev;
+ void (*enable)(enum twl4030_led led, bool enable);
+ enum led_brightness new_brightness;
+ enum led_brightness old_brightness;
+ enum twl4030_led id;
+ int module;
+ struct work_struct work;
+};
+
+static int twl4030_clear_set(u8 mod_no, u8 clear, u8 set, u8 reg)
+{
+ u8 val = 0;
+ int ret;
+
+ ret = twl_i2c_read_u8(mod_no, &val, reg);
+ if (ret)
+ return ret;
+
+ val &= ~clear;
+ val |= set;
+
+ return twl_i2c_write_u8(mod_no, val, reg);
+}
+
+static void twl4030_enable_ledab(enum twl4030_led led, bool enable)
+{
+ u8 bits;
+
+ if (led == TWL4030_LEDA)
+ bits = LEDEN_LEDAON | LEDEN_LEDAPWM;
+ else
+ bits = LEDEN_LEDBON | LEDEN_LEDBPWM;
+
+ if (enable)
+ twl4030_clear_set(TWL4030_MODULE_LED, 0, bits, TWL4030_LED_LEDEN);
+ else
+ twl4030_clear_set(TWL4030_MODULE_LED, bits, 0, TWL4030_LED_LEDEN);
+}
+
+static void twl4030_enable_pwm01(enum twl4030_led led, bool enable)
+{
+ u8 r, enbit, clkbit;
+
+ if (led == TWL4030_PWM0) {
+ enbit = GPBR1_PWM0_ENABLE;
+ clkbit = GPBR1_PWM0_CLK_ENABLE;
+ } else {
+ enbit = GPBR1_PWM1_ENABLE;
+ clkbit = GPBR1_PWM1_CLK_ENABLE;
+ }
+
+ twl_i2c_read_u8(TWL4030_MODULE_INTBR, &r, TWL_INTBR_GPBR1);
+
+ if (enable) {
+ /* first enable clock, then PWM out */
+ r &= ~enbit;
+ r |= clkbit;
+ twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
+ r |= enbit;
+ } else {
+ /* first disable PWM output, then clock */
+ r &= ~enbit;
+ twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
+ r &= ~clkbit;
+ }
+
+ twl_i2c_write_u8(TWL4030_MODULE_INTBR, r, TWL_INTBR_GPBR1);
+}
+
+static void twl4030_pwmled_work(struct work_struct *work)
+{
+ struct twl4030_pwmled *led;
+ int val;
+
+ led = container_of(work, struct twl4030_pwmled, work);
+
+ if (led->new_brightness == LED_OFF) {
+ if (led->old_brightness != LED_OFF)
+ led->enable(led->id, 0);
+ goto out;
+ }
+
+ val = led->new_brightness * 0x7f / LED_FULL;
+ /* avoid 0: on = off = 0 means full brightness */
+ if (val == 0)
+ val = 1;
+
+ twl_i2c_write_u8(led->module, val, TWL4030_PWMx_PWMxOFF);
+
+ if (led->old_brightness == LED_OFF)
+ led->enable(led->id, 1);
+
+out:
+ led->old_brightness = led->new_brightness;
+}
+
+static void twl4030_pwmled_brightness(struct led_classdev *cdev,
+ enum led_brightness b)
+{
+ struct twl4030_pwmled *led;
+
+ led = container_of(cdev, struct twl4030_pwmled, cdev);
+ led->new_brightness = b;
+ schedule_work(&led->work);
+}
+
+static int __devinit twl4030_pwmled_probe(struct platform_device *pdev)
+{
+ const struct led_pwm_platform_data *pdata = pdev->dev.platform_data;
+ struct twl4030_pwmled *led, *leds;
+ int ret;
+ int i;
+
+ pdata = pdev->dev.platform_data;
+ if (!pdata || pdata->num_leds < 1 || pdata->num_leds > 4)
+ return -ENODEV;
+
+ leds = kcalloc(pdata->num_leds, sizeof(*leds), GFP_KERNEL);
+ if (!leds)
+ return -ENOMEM;
+
+ for (i = 0; i < pdata->num_leds; i++) {
+ led = &leds[i];
+ led->cdev.name = pdata->leds[i].name;
+ led->cdev.brightness = LED_OFF;
+ led->cdev.brightness_set = twl4030_pwmled_brightness;
+ led->cdev.default_trigger = pdata->leds[i].default_trigger;
+ led->id = pdata->leds[i].pwm_id;
+ led->old_brightness = -1; /* unknown */
+
+ switch (pdata->leds[i].pwm_id) {
+ case TWL4030_LEDA:
+ led->module = TWL4030_MODULE_PWMA;
+ led->enable = twl4030_enable_ledab;
+ break;
+ case TWL4030_LEDB:
+ led->module = TWL4030_MODULE_PWMB;
+ led->enable = twl4030_enable_ledab;
+ break;
+ case TWL4030_PWM0:
+ led->module = TWL4030_MODULE_PWM0;
+ led->enable = twl4030_enable_pwm01;
+ /* enable PWM0 in pin mux */
+ twl4030_clear_set(TWL4030_MODULE_INTBR,
+ 0x0c, 0x04, TWL_INTBR_PMBR1);
+ break;
+ case TWL4030_PWM1:
+ led->module = TWL4030_MODULE_PWM1;
+ led->enable = twl4030_enable_pwm01;
+ twl4030_clear_set(TWL4030_MODULE_INTBR,
+ 0, 0x30, TWL_INTBR_PMBR1);
+ break;
+ default:
+ dev_err(&pdev->dev, "invalid pwm_id: %d\n",
+ pdata->leds->pwm_id);
+ ret = -ENODEV;
+ goto err;
+ }
+ INIT_WORK(&led->work, twl4030_pwmled_work);
+
+ twl_i2c_write_u8(led->module, 0, TWL4030_PWMx_PWMxON);
+
+ /* Hand it over to the LED framework */
+ ret = led_classdev_register(&pdev->dev, &led->cdev);
+ if (ret < 0)
+ goto err;
+ }
+
+ platform_set_drvdata(pdev, leds);
+ return 0;
+
+err:
+ for (--i; i >= 0; i--)
+ led_classdev_unregister(&leds[i].cdev);
+ kfree(leds);
+
+ return ret;
+}
+
+static int __devexit twl4030_pwmled_remove(struct platform_device *pdev)
+{
+ const struct led_pwm_platform_data *pdata = pdev->dev.platform_data;
+ struct twl4030_pwmled *leds;
+ int i;
+
+ leds = platform_get_drvdata(pdev);
+
+ for (i = 0; i < pdata->num_leds; i++) {
+ led_classdev_unregister(&leds[i].cdev);
+ cancel_work_sync(&leds[i].work);
+ }
+
+ kfree(leds);
+ platform_set_drvdata(pdev, NULL);
+ return 0;
+}
+
+static struct platform_driver twl4030_pwmled_driver = {
+ .driver = {
+ .name = "leds-twl4030-pwm",
+ .owner = THIS_MODULE,
+ },
+ .probe = twl4030_pwmled_probe,
+ .remove = __devexit_p(twl4030_pwmled_remove),
+};
+
+static int __init twl4030_pwm_init(void)
+{
+ return platform_driver_register(&twl4030_pwmled_driver);
+}
+module_init(twl4030_pwm_init);
+
+static void __exit twl4030_pwm_exit(void)
+{
+ platform_driver_unregister(&twl4030_pwmled_driver);
+}
+module_exit(twl4030_pwm_exit);
+
+MODULE_AUTHOR("Gražvydas Ignotas");
+MODULE_DESCRIPTION("Driver for TWL4030 PWM controlled LEDs");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:leds-twl4030-pwm");
git.openpandora.org / pandora-kernel.git / blobdiff