1 From daf08289dc0ac69af0d8293dacd5ca6291400593 Mon Sep 17 00:00:00 2001
2 From: John Crispin <blogic@openwrt.org>
3 Date: Sun, 24 Mar 2013 17:17:17 +0100
4 Subject: [PATCH 30/33] owrt: MIPS: ralink: add pseudo pwm led trigger based
7 Signed-off-by: John Crispin <blogic@openwrt.org>
9 arch/mips/ralink/timer.c | 213 ++++++++++++++++++++++++++++++++++++++++++----
10 1 file changed, 197 insertions(+), 16 deletions(-)
12 --- a/arch/mips/ralink/timer.c
13 +++ b/arch/mips/ralink/timer.c
15 #include <linux/timer.h>
16 #include <linux/of_gpio.h>
17 #include <linux/clk.h>
18 +#include <linux/leds.h>
19 +#include <linux/slab.h>
21 #include <asm/mach-ralink/ralink_regs.h>
25 #define TMR0CTL_ENABLE BIT(7)
26 #define TMR0CTL_MODE_PERIODIC BIT(4)
27 -#define TMR0CTL_PRESCALER 1
28 +#define TMR0CTL_PRESCALER 2
29 #define TMR0CTL_PRESCALE_VAL (0xf - TMR0CTL_PRESCALER)
30 #define TMR0CTL_PRESCALE_DIV (65536 / BIT(TMR0CTL_PRESCALER))
32 +struct rt_timer_gpio {
33 + struct list_head list;
34 + struct led_classdev *led;
39 - void __iomem *membase;
41 - unsigned long timer_freq;
42 - unsigned long timer_div;
44 + void __iomem *membase;
47 + unsigned long timer_freq;
48 + unsigned long timer_div;
50 + struct list_head gpios;
51 + struct led_trigger led_trigger;
52 + unsigned int duty_cycle;
56 + unsigned int fade_min;
57 + unsigned int fade_max;
58 + unsigned int fade_speed;
59 + unsigned int fade_dir;
60 + unsigned int fade_count;
63 static inline void rt_timer_w32(struct rt_timer *rt, u8 reg, u32 val)
64 @@ -48,18 +68,46 @@ static inline u32 rt_timer_r32(struct rt
65 static irqreturn_t rt_timer_irq(int irq, void *_rt)
67 struct rt_timer *rt = (struct rt_timer *) _rt;
68 + struct rt_timer_gpio *gpio;
71 - rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
72 + if (rt->fade && (rt->fade_count++ > rt->fade_speed)) {
74 + if (rt->duty_cycle <= rt->fade_min)
76 + else if (rt->duty_cycle >= rt->fade_max)
80 + rt->duty_cycle += 1;
82 + rt->duty_cycle -= 1;
86 + val = rt->timer_freq / rt->timer_div;
88 + val *= rt->duty_cycle;
90 + val *= (100 - rt->duty_cycle);
93 + if (!list_empty(&rt->gpios))
94 + list_for_each_entry(gpio, &rt->gpios, list)
95 + led_set_brightness(gpio->led, !!rt->duty);
97 + rt->duty = !rt->duty;
99 + rt_timer_w32(rt, TIMER_REG_TMR0LOAD, val + 1);
100 rt_timer_w32(rt, TIMER_REG_TMRSTAT, TMRSTAT_TMR0INT);
106 static int rt_timer_request(struct rt_timer *rt)
108 - int err = request_irq(rt->irq, rt_timer_irq, IRQF_DISABLED,
109 - dev_name(rt->dev), rt);
110 + int err = devm_request_irq(rt->dev, rt->irq, rt_timer_irq,
111 + IRQF_DISABLED, dev_name(rt->dev), rt);
113 dev_err(rt->dev, "failed to request irq\n");
115 @@ -81,8 +129,6 @@ static int rt_timer_config(struct rt_tim
117 rt->timer_div = divisor;
119 - rt_timer_w32(rt, TIMER_REG_TMR0LOAD, rt->timer_freq / rt->timer_div);
124 @@ -108,11 +154,128 @@ static void rt_timer_disable(struct rt_t
125 rt_timer_w32(rt, TIMER_REG_TMR0CTL, t);
128 +static ssize_t led_fade_show(struct device *dev,
129 + struct device_attribute *attr, char *buf)
131 + struct led_classdev *led_cdev = dev_get_drvdata(dev);
132 + struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
134 + return sprintf(buf, "speed: %d, min: %d, max: %d\n", rt->fade_speed, rt->fade_min, rt->fade_max);
137 +static ssize_t led_fade_store(struct device *dev,
138 + struct device_attribute *attr, const char *buf, size_t size)
140 + struct led_classdev *led_cdev = dev_get_drvdata(dev);
141 + struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
142 + unsigned int speed = 0, min = 0, max = 0;
143 + ssize_t ret = -EINVAL;
145 + ret = sscanf(buf, "%u %u %u", &speed, &min, &max);
148 + rt->fade_speed = speed;
149 + rt->fade_min = min;
150 + rt->fade_max = max;
159 +static DEVICE_ATTR(fade, 0644, led_fade_show, led_fade_store);
161 +static ssize_t led_duty_cycle_show(struct device *dev,
162 + struct device_attribute *attr, char *buf)
164 + struct led_classdev *led_cdev = dev_get_drvdata(dev);
165 + struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
167 + return sprintf(buf, "%u\n", rt->duty_cycle);
170 +static ssize_t led_duty_cycle_store(struct device *dev,
171 + struct device_attribute *attr, const char *buf, size_t size)
173 + struct led_classdev *led_cdev = dev_get_drvdata(dev);
174 + struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
175 + unsigned long state;
176 + ssize_t ret = -EINVAL;
178 + ret = kstrtoul(buf, 10, &state);
183 + rt->duty_cycle = state;
185 + rt->duty_cycle = 100;
192 +static DEVICE_ATTR(duty_cycle, 0644, led_duty_cycle_show, led_duty_cycle_store);
194 +static void rt_timer_trig_activate(struct led_classdev *led_cdev)
196 + struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
197 + struct rt_timer_gpio *gpio_data;
200 + led_cdev->trigger_data = NULL;
201 + gpio_data = kzalloc(sizeof(*gpio_data), GFP_KERNEL);
205 + rc = device_create_file(led_cdev->dev, &dev_attr_duty_cycle);
208 + rc = device_create_file(led_cdev->dev, &dev_attr_fade);
210 + goto err_out_duty_cycle;
212 + led_cdev->activated = true;
213 + led_cdev->trigger_data = gpio_data;
214 + gpio_data->led = led_cdev;
215 + list_add(&gpio_data->list, &rt->gpios);
216 + led_cdev->trigger_data = gpio_data;
217 + rt_timer_enable(rt);
221 + device_remove_file(led_cdev->dev, &dev_attr_duty_cycle);
227 +static void rt_timer_trig_deactivate(struct led_classdev *led_cdev)
229 + struct rt_timer *rt = container_of(led_cdev->trigger, struct rt_timer, led_trigger);
230 + struct rt_timer_gpio *gpio_data = (struct rt_timer_gpio*) led_cdev->trigger_data;
232 + if (led_cdev->activated) {
233 + device_remove_file(led_cdev->dev, &dev_attr_duty_cycle);
234 + device_remove_file(led_cdev->dev, &dev_attr_fade);
235 + led_cdev->activated = false;
238 + list_del(&gpio_data->list);
239 + rt_timer_disable(rt);
240 + led_set_brightness(led_cdev, LED_OFF);
243 static int rt_timer_probe(struct platform_device *pdev)
245 struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
246 + const __be32 *divisor;
252 dev_err(&pdev->dev, "no memory resource found\n");
253 @@ -147,12 +310,29 @@ static int rt_timer_probe(struct platfor
257 + rt->duty_cycle = 100;
258 rt->dev = &pdev->dev;
259 platform_set_drvdata(pdev, rt);
261 - rt_timer_request(rt);
262 - rt_timer_config(rt, 2);
263 - rt_timer_enable(rt);
264 + ret = rt_timer_request(rt);
268 + divisor = of_get_property(pdev->dev.of_node, "ralink,divisor", NULL);
270 + rt_timer_config(rt, be32_to_cpu(*divisor));
272 + rt_timer_config(rt, 200);
274 + rt->led_trigger.name = "pwmtimer",
275 + rt->led_trigger.activate = rt_timer_trig_activate,
276 + rt->led_trigger.deactivate = rt_timer_trig_deactivate,
278 + ret = led_trigger_register(&rt->led_trigger);
282 + INIT_LIST_HEAD(&rt->gpios);
284 dev_info(&pdev->dev, "maximum frequncy is %luHz\n", rt->timer_freq);
286 @@ -163,6 +343,7 @@ static int rt_timer_remove(struct platfo
288 struct rt_timer *rt = platform_get_drvdata(pdev);
290 + led_trigger_unregister(&rt->led_trigger);
291 rt_timer_disable(rt);
294 @@ -187,6 +368,6 @@ static struct platform_driver rt_timer_d
296 module_platform_driver(rt_timer_driver);
298 -MODULE_DESCRIPTION("Ralink RT2880 timer");
299 +MODULE_DESCRIPTION("Ralink RT2880 timer / pseudo pwm");
300 MODULE_AUTHOR("John Crispin <blogic@openwrt.org");
301 MODULE_LICENSE("GPL");