--- /dev/null
+From 9de00286e20a5f5edc419698373010f1cb6ff0ce Mon Sep 17 00:00:00 2001
+From: John Crispin <blogic@openwrt.org>
+Date: Sun, 27 Jul 2014 09:25:02 +0100
+Subject: [PATCH 19/57] MIPS: ralink: add pseudo pwm led trigger based on
+ timer0
+
+Signed-off-by: John Crispin <blogic@openwrt.org>
+---
+ arch/mips/ralink/timer.c | 213 ++++++++++++++++++++++++++++++++++++++++++----
+ 1 file changed, 197 insertions(+), 16 deletions(-)
+
+diff --git a/arch/mips/ralink/timer.c b/arch/mips/ralink/timer.c
+index e38692a..a71a7cb 100644
+--- a/arch/mips/ralink/timer.c
++++ b/arch/mips/ralink/timer.c
+@@ -12,6 +12,8 @@
+ #include <linux/timer.h>
+ #include <linux/of_gpio.h>
+ #include <linux/clk.h>
++#include <linux/leds.h>
++#include <linux/slab.h>
+
+ #include <asm/mach-ralink/ralink_regs.h>
+
+@@ -23,16 +25,34 @@
+
+ #define TMR0CTL_ENABLE BIT(7)
+ #define TMR0CTL_MODE_PERIODIC BIT(4)
+-#define TMR0CTL_PRESCALER 1
++#define TMR0CTL_PRESCALER 2
+ #define TMR0CTL_PRESCALE_VAL (0xf - TMR0CTL_PRESCALER)
+ #define TMR0CTL_PRESCALE_DIV (65536 / BIT(TMR0CTL_PRESCALER))
+
++struct rt_timer_gpio {
++ struct list_head list;
++ struct led_classdev *led;
++};
++
+ struct rt_timer {
+- struct device *dev;
+- void __iomem *membase;
+- int irq;
+- unsigned long timer_freq;
+- unsigned long timer_div;
++ struct device *dev;
++ void __iomem *membase;
++ int irq;
++
++ unsigned long timer_freq;
++ unsigned long timer_div;
++
++ struct list_head gpios;
++ struct led_trigger led_trigger;
++ unsigned int duty_cycle;
++ unsigned int duty;
++
++ unsigned int fade;
++ unsigned int fade_min;
++ unsigned int fade_max;
++ unsigned int fade_speed;
++ unsigned int fade_dir;
++ unsigned int fade_count;
+ };
+
+ static inline void rt_timer_w32(struct rt_timer *rt, u8 reg, u32 val)
+@@ -48,18 +68,46 @@ static inline u32 rt_timer_r32(struct rt_timer *rt, u8 reg)
+ static irqreturn_t rt_timer_irq(int irq, void *_rt)
+ {
+ struct rt_timer *rt = (struct rt_timer *) _rt;
++ struct rt_timer_gpio *gpio;
++ unsigned int val;
+
+- rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
++ if (rt->fade && (rt->fade_count++ > rt->fade_speed)) {
++ rt->fade_count = 0;
++ if (rt->duty_cycle <= rt->fade_min)
++ rt->fade_dir = 1;
++ else if (rt->duty_cycle >= rt->fade_max)
++ rt->fade_dir = 0;
++
++ if (rt->fade_dir)
++ rt->duty_cycle += 1;
++ else
++ rt->duty_cycle -= 1;
++
++ }
++
++ val = rt->timer_freq / rt->timer_div;
++ if (rt->duty)
++ val *= rt->duty_cycle;
++ else
++ val *= (100 - rt->duty_cycle);
++ val /= 100;
++
++ if (!list_empty(&rt->gpios))
++ list_for_each_entry(gpio, &rt->gpios, list)
++ led_set_brightness(gpio->led, !!rt->duty);
++
++ rt->duty = !rt->duty;
++
++ rt_timer_w32(rt, TIMER_REG_TMR0LOAD, val + 1);
+ rt_timer_w32(rt, TIMER_REG_TMRSTAT, TMRSTAT_TMR0INT);
+
+ return IRQ_HANDLED;
+ }
+
+-
+ static int rt_timer_request(struct rt_timer *rt)
+ {
+- int err = request_irq(rt->irq, rt_timer_irq, IRQF_DISABLED,
+- dev_name(rt->dev), rt);
++ int err = devm_request_irq(rt->dev, rt->irq, rt_timer_irq,
++ IRQF_DISABLED, dev_name(rt->dev), rt);
+ if (err) {
+ dev_err(rt->dev, "failed to request irq\n");
+ } else {
+@@ -81,8 +129,6 @@ static int rt_timer_config(struct rt_timer *rt, unsigned long divisor)
+ else
+ rt->timer_div = divisor;
+
+- rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
+-
+ return 0;
+ }
+
+@@ -108,11 +154,128 @@ static void rt_timer_disable(struct rt_timer *rt)
+ rt_timer_w32(rt, TIMER_REG_TMR0CTL, t);
+ }
+
++static ssize_t led_fade_show(struct device *dev,
++ struct device_attribute *attr, char *buf)
++{
++ struct led_classdev *led_cdev = dev_get_drvdata(dev);
++ struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
++
++ return sprintf(buf, "speed: %d, min: %d, max: %d\n", rt->fade_speed, rt->fade_min, rt->fade_max);
++}
++
++static ssize_t led_fade_store(struct device *dev,
++ struct device_attribute *attr, const char *buf, size_t size)
++{
++ struct led_classdev *led_cdev = dev_get_drvdata(dev);
++ struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
++ unsigned int speed = 0, min = 0, max = 0;
++ ssize_t ret = -EINVAL;
++
++ ret = sscanf(buf, "%u %u %u", &speed, &min, &max);
++
++ if (ret == 3) {
++ rt->fade_speed = speed;
++ rt->fade_min = min;
++ rt->fade_max = max;
++ rt->fade = 1;
++ } else {
++ rt->fade = 0;
++ }
++
++ return size;
++}
++
++static DEVICE_ATTR(fade, 0644, led_fade_show, led_fade_store);
++
++static ssize_t led_duty_cycle_show(struct device *dev,
++ struct device_attribute *attr, char *buf)
++{
++ struct led_classdev *led_cdev = dev_get_drvdata(dev);
++ struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
++
++ return sprintf(buf, "%u\n", rt->duty_cycle);
++}
++
++static ssize_t led_duty_cycle_store(struct device *dev,
++ struct device_attribute *attr, const char *buf, size_t size)
++{
++ struct led_classdev *led_cdev = dev_get_drvdata(dev);
++ struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
++ unsigned long state;
++ ssize_t ret = -EINVAL;
++
++ ret = kstrtoul(buf, 10, &state);
++ if (ret)
++ return ret;
++
++ if (state <= 100)
++ rt->duty_cycle = state;
++ else
++ rt->duty_cycle = 100;
++
++ rt->fade = 0;
++
++ return size;
++}
++
++static DEVICE_ATTR(duty_cycle, 0644, led_duty_cycle_show, led_duty_cycle_store);
++
++static void rt_timer_trig_activate(struct led_classdev *led_cdev)
++{
++ struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
++ struct rt_timer_gpio *gpio_data;
++ int rc;
++
++ led_cdev->trigger_data = NULL;
++ gpio_data = kzalloc(sizeof(*gpio_data), GFP_KERNEL);
++ if (!gpio_data)
++ return;
++
++ rc = device_create_file(led_cdev->dev, &dev_attr_duty_cycle);
++ if (rc)
++ goto err_gpio;
++ rc = device_create_file(led_cdev->dev, &dev_attr_fade);
++ if (rc)
++ goto err_out_duty_cycle;
++
++ led_cdev->activated = true;
++ led_cdev->trigger_data = gpio_data;
++ gpio_data->led = led_cdev;
++ list_add(&gpio_data->list, &rt->gpios);
++ led_cdev->trigger_data = gpio_data;
++ rt_timer_enable(rt);
++ return;
++
++err_out_duty_cycle:
++ device_remove_file(led_cdev->dev, &dev_attr_duty_cycle);
++
++err_gpio:
++ kfree(gpio_data);
++}
++
++static void rt_timer_trig_deactivate(struct led_classdev *led_cdev)
++{
++ struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
++ struct rt_timer_gpio *gpio_data = (struct rt_timer_gpio*) led_cdev->trigger_data;
++
++ if (led_cdev->activated) {
++ device_remove_file(led_cdev->dev, &dev_attr_duty_cycle);
++ device_remove_file(led_cdev->dev, &dev_attr_fade);
++ led_cdev->activated = false;
++ }
++
++ list_del(&gpio_data->list);
++ rt_timer_disable(rt);
++ led_set_brightness(led_cdev, LED_OFF);
++}
++
+ static int rt_timer_probe(struct platform_device *pdev)
+ {
+ struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
++ const __be32 *divisor;
+ struct rt_timer *rt;
+ struct clk *clk;
++ int ret;
+
+ rt = devm_kzalloc(&pdev->dev, sizeof(*rt), GFP_KERNEL);
+ if (!rt) {
+@@ -140,12 +303,29 @@ static int rt_timer_probe(struct platform_device *pdev)
+ if (!rt->timer_freq)
+ return -EINVAL;
+
++ rt->duty_cycle = 100;
+ rt->dev = &pdev->dev;
+ platform_set_drvdata(pdev, rt);
+
+- rt_timer_request(rt);
+- rt_timer_config(rt, 2);
+- rt_timer_enable(rt);
++ ret = rt_timer_request(rt);
++ if (ret)
++ return ret;
++
++ divisor = of_get_property(pdev->dev.of_node, "ralink,divisor", NULL);
++ if (divisor)
++ rt_timer_config(rt, be32_to_cpu(*divisor));
++ else
++ rt_timer_config(rt, 200);
++
++ rt->led_trigger.name = "pwmtimer",
++ rt->led_trigger.activate = rt_timer_trig_activate,
++ rt->led_trigger.deactivate = rt_timer_trig_deactivate,
++
++ ret = led_trigger_register(&rt->led_trigger);
++ if (ret)
++ return ret;
++
++ INIT_LIST_HEAD(&rt->gpios);
+
+ dev_info(&pdev->dev, "maximum frequency is %luHz\n", rt->timer_freq);
+
+@@ -156,6 +336,7 @@ static int rt_timer_remove(struct platform_device *pdev)
+ {
+ struct rt_timer *rt = platform_get_drvdata(pdev);
+
++ led_trigger_unregister(&rt->led_trigger);
+ rt_timer_disable(rt);
+ rt_timer_free(rt);
+
+@@ -180,6 +361,6 @@ static struct platform_driver rt_timer_driver = {
+
+ module_platform_driver(rt_timer_driver);
+
+-MODULE_DESCRIPTION("Ralink RT2880 timer");
++MODULE_DESCRIPTION("Ralink RT2880 timer / pseudo pwm");
+ MODULE_AUTHOR("John Crispin <blogic@openwrt.org");
+ MODULE_LICENSE("GPL");
+--
+1.7.10.4
+
projects / openwrt.git / blobdiff