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8#include <linux/io.h>
9#include <linux/leds.h>
10#include <linux/module.h>
11#include <linux/of.h>
12#include <linux/platform_device.h>
13#include <linux/spinlock.h>
14
15#define BCM6328_REG_INIT 0x00
16#define BCM6328_REG_MODE_HI 0x04
17#define BCM6328_REG_MODE_LO 0x08
18#define BCM6328_REG_HWDIS 0x0c
19#define BCM6328_REG_STROBE 0x10
20#define BCM6328_REG_LNKACTSEL_HI 0x14
21#define BCM6328_REG_LNKACTSEL_LO 0x18
22#define BCM6328_REG_RBACK 0x1c
23#define BCM6328_REG_SERMUX 0x20
24
25#define BCM6328_LED_MAX_COUNT 24
26#define BCM6328_LED_DEF_DELAY 500
27#define BCM6328_LED_INTERVAL_MS 20
28
29#define BCM6328_LED_INTV_MASK 0x3f
30#define BCM6328_LED_FAST_INTV_SHIFT 6
31#define BCM6328_LED_FAST_INTV_MASK (BCM6328_LED_INTV_MASK << \
32 BCM6328_LED_FAST_INTV_SHIFT)
33#define BCM6328_SERIAL_LED_EN BIT(12)
34#define BCM6328_SERIAL_LED_MUX BIT(13)
35#define BCM6328_SERIAL_LED_CLK_NPOL BIT(14)
36#define BCM6328_SERIAL_LED_DATA_PPOL BIT(15)
37#define BCM6328_SERIAL_LED_SHIFT_DIR BIT(16)
38#define BCM6328_LED_SHIFT_TEST BIT(30)
39#define BCM6328_LED_TEST BIT(31)
40#define BCM6328_INIT_MASK (BCM6328_SERIAL_LED_EN | \
41 BCM6328_SERIAL_LED_MUX | \
42 BCM6328_SERIAL_LED_CLK_NPOL | \
43 BCM6328_SERIAL_LED_DATA_PPOL | \
44 BCM6328_SERIAL_LED_SHIFT_DIR)
45
46#define BCM6328_LED_MODE_MASK 3
47#define BCM6328_LED_MODE_ON 0
48#define BCM6328_LED_MODE_FAST 1
49#define BCM6328_LED_MODE_BLINK 2
50#define BCM6328_LED_MODE_OFF 3
51#define BCM6328_LED_SHIFT(X) ((X) << 1)
52
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61
62
63struct bcm6328_led {
64 struct led_classdev cdev;
65 void __iomem *mem;
66 spinlock_t *lock;
67 unsigned long pin;
68 unsigned long *blink_leds;
69 unsigned long *blink_delay;
70 bool active_low;
71};
72
73static void bcm6328_led_write(void __iomem *reg, unsigned long data)
74{
75#ifdef CONFIG_CPU_BIG_ENDIAN
76 iowrite32be(data, reg);
77#else
78 writel(data, reg);
79#endif
80}
81
82static unsigned long bcm6328_led_read(void __iomem *reg)
83{
84#ifdef CONFIG_CPU_BIG_ENDIAN
85 return ioread32be(reg);
86#else
87 return readl(reg);
88#endif
89}
90
91
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93
94
95
96
97static unsigned long bcm6328_pin2shift(unsigned long pin)
98{
99 if (pin < 8)
100 return pin + 16;
101 else
102 return pin - 8;
103}
104
105static void bcm6328_led_mode(struct bcm6328_led *led, unsigned long value)
106{
107 void __iomem *mode;
108 unsigned long val, shift;
109
110 shift = bcm6328_pin2shift(led->pin);
111 if (shift / 16)
112 mode = led->mem + BCM6328_REG_MODE_HI;
113 else
114 mode = led->mem + BCM6328_REG_MODE_LO;
115
116 val = bcm6328_led_read(mode);
117 val &= ~(BCM6328_LED_MODE_MASK << BCM6328_LED_SHIFT(shift % 16));
118 val |= (value << BCM6328_LED_SHIFT(shift % 16));
119 bcm6328_led_write(mode, val);
120}
121
122static void bcm6328_led_set(struct led_classdev *led_cdev,
123 enum led_brightness value)
124{
125 struct bcm6328_led *led =
126 container_of(led_cdev, struct bcm6328_led, cdev);
127 unsigned long flags;
128
129 spin_lock_irqsave(led->lock, flags);
130 *(led->blink_leds) &= ~BIT(led->pin);
131 if ((led->active_low && value == LED_OFF) ||
132 (!led->active_low && value != LED_OFF))
133 bcm6328_led_mode(led, BCM6328_LED_MODE_ON);
134 else
135 bcm6328_led_mode(led, BCM6328_LED_MODE_OFF);
136 spin_unlock_irqrestore(led->lock, flags);
137}
138
139static unsigned long bcm6328_blink_delay(unsigned long delay)
140{
141 unsigned long bcm6328_delay;
142
143 bcm6328_delay = delay + BCM6328_LED_INTERVAL_MS / 2;
144 bcm6328_delay = bcm6328_delay / BCM6328_LED_INTERVAL_MS;
145 if (bcm6328_delay == 0)
146 bcm6328_delay = 1;
147
148 return bcm6328_delay;
149}
150
151static int bcm6328_blink_set(struct led_classdev *led_cdev,
152 unsigned long *delay_on, unsigned long *delay_off)
153{
154 struct bcm6328_led *led =
155 container_of(led_cdev, struct bcm6328_led, cdev);
156 unsigned long delay, flags;
157 int rc;
158
159 if (!*delay_on)
160 *delay_on = BCM6328_LED_DEF_DELAY;
161 if (!*delay_off)
162 *delay_off = BCM6328_LED_DEF_DELAY;
163
164 delay = bcm6328_blink_delay(*delay_on);
165 if (delay != bcm6328_blink_delay(*delay_off)) {
166 dev_dbg(led_cdev->dev,
167 "fallback to soft blinking (delay_on != delay_off)\n");
168 return -EINVAL;
169 }
170
171 if (delay > BCM6328_LED_INTV_MASK) {
172 dev_dbg(led_cdev->dev,
173 "fallback to soft blinking (delay > %ums)\n",
174 BCM6328_LED_INTV_MASK * BCM6328_LED_INTERVAL_MS);
175 return -EINVAL;
176 }
177
178 spin_lock_irqsave(led->lock, flags);
179 if (*(led->blink_leds) == 0 ||
180 *(led->blink_leds) == BIT(led->pin) ||
181 *(led->blink_delay) == delay) {
182 unsigned long val;
183
184 *(led->blink_leds) |= BIT(led->pin);
185 *(led->blink_delay) = delay;
186
187 val = bcm6328_led_read(led->mem + BCM6328_REG_INIT);
188 val &= ~BCM6328_LED_FAST_INTV_MASK;
189 val |= (delay << BCM6328_LED_FAST_INTV_SHIFT);
190 bcm6328_led_write(led->mem + BCM6328_REG_INIT, val);
191
192 bcm6328_led_mode(led, BCM6328_LED_MODE_BLINK);
193 rc = 0;
194 } else {
195 dev_dbg(led_cdev->dev,
196 "fallback to soft blinking (delay already set)\n");
197 rc = -EINVAL;
198 }
199 spin_unlock_irqrestore(led->lock, flags);
200
201 return rc;
202}
203
204static int bcm6328_hwled(struct device *dev, struct device_node *nc, u32 reg,
205 void __iomem *mem, spinlock_t *lock)
206{
207 int i, cnt;
208 unsigned long flags, val;
209
210 spin_lock_irqsave(lock, flags);
211 val = bcm6328_led_read(mem + BCM6328_REG_HWDIS);
212 val &= ~BIT(reg);
213 bcm6328_led_write(mem + BCM6328_REG_HWDIS, val);
214 spin_unlock_irqrestore(lock, flags);
215
216
217 if (reg >= 8)
218 return 0;
219
220 cnt = of_property_count_elems_of_size(nc, "brcm,link-signal-sources",
221 sizeof(u32));
222 for (i = 0; i < cnt; i++) {
223 u32 sel;
224 void __iomem *addr;
225
226 if (reg < 4)
227 addr = mem + BCM6328_REG_LNKACTSEL_LO;
228 else
229 addr = mem + BCM6328_REG_LNKACTSEL_HI;
230
231 of_property_read_u32_index(nc, "brcm,link-signal-sources", i,
232 &sel);
233
234 if (reg / 4 != sel / 4) {
235 dev_warn(dev, "invalid link signal source\n");
236 continue;
237 }
238
239 spin_lock_irqsave(lock, flags);
240 val = bcm6328_led_read(addr);
241 val |= (BIT(reg % 4) << (((sel % 4) * 4) + 16));
242 bcm6328_led_write(addr, val);
243 spin_unlock_irqrestore(lock, flags);
244 }
245
246 cnt = of_property_count_elems_of_size(nc,
247 "brcm,activity-signal-sources",
248 sizeof(u32));
249 for (i = 0; i < cnt; i++) {
250 u32 sel;
251 void __iomem *addr;
252
253 if (reg < 4)
254 addr = mem + BCM6328_REG_LNKACTSEL_LO;
255 else
256 addr = mem + BCM6328_REG_LNKACTSEL_HI;
257
258 of_property_read_u32_index(nc, "brcm,activity-signal-sources",
259 i, &sel);
260
261 if (reg / 4 != sel / 4) {
262 dev_warn(dev, "invalid activity signal source\n");
263 continue;
264 }
265
266 spin_lock_irqsave(lock, flags);
267 val = bcm6328_led_read(addr);
268 val |= (BIT(reg % 4) << ((sel % 4) * 4));
269 bcm6328_led_write(addr, val);
270 spin_unlock_irqrestore(lock, flags);
271 }
272
273 return 0;
274}
275
276static int bcm6328_led(struct device *dev, struct device_node *nc, u32 reg,
277 void __iomem *mem, spinlock_t *lock,
278 unsigned long *blink_leds, unsigned long *blink_delay)
279{
280 struct bcm6328_led *led;
281 const char *state;
282 int rc;
283
284 led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);
285 if (!led)
286 return -ENOMEM;
287
288 led->pin = reg;
289 led->mem = mem;
290 led->lock = lock;
291 led->blink_leds = blink_leds;
292 led->blink_delay = blink_delay;
293
294 if (of_property_read_bool(nc, "active-low"))
295 led->active_low = true;
296
297 led->cdev.name = of_get_property(nc, "label", NULL) ? : nc->name;
298 led->cdev.default_trigger = of_get_property(nc,
299 "linux,default-trigger",
300 NULL);
301
302 if (!of_property_read_string(nc, "default-state", &state)) {
303 if (!strcmp(state, "on")) {
304 led->cdev.brightness = LED_FULL;
305 } else if (!strcmp(state, "keep")) {
306 void __iomem *mode;
307 unsigned long val, shift;
308
309 shift = bcm6328_pin2shift(led->pin);
310 if (shift / 16)
311 mode = mem + BCM6328_REG_MODE_HI;
312 else
313 mode = mem + BCM6328_REG_MODE_LO;
314
315 val = bcm6328_led_read(mode) >>
316 BCM6328_LED_SHIFT(shift % 16);
317 val &= BCM6328_LED_MODE_MASK;
318 if ((led->active_low && val == BCM6328_LED_MODE_OFF) ||
319 (!led->active_low && val == BCM6328_LED_MODE_ON))
320 led->cdev.brightness = LED_FULL;
321 else
322 led->cdev.brightness = LED_OFF;
323 } else {
324 led->cdev.brightness = LED_OFF;
325 }
326 } else {
327 led->cdev.brightness = LED_OFF;
328 }
329
330 bcm6328_led_set(&led->cdev, led->cdev.brightness);
331
332 led->cdev.brightness_set = bcm6328_led_set;
333 led->cdev.blink_set = bcm6328_blink_set;
334
335 rc = led_classdev_register(dev, &led->cdev);
336 if (rc < 0)
337 return rc;
338
339 dev_dbg(dev, "registered LED %s\n", led->cdev.name);
340
341 return 0;
342}
343
344static int bcm6328_leds_probe(struct platform_device *pdev)
345{
346 struct device *dev = &pdev->dev;
347 struct device_node *np = pdev->dev.of_node;
348 struct device_node *child;
349 struct resource *mem_r;
350 void __iomem *mem;
351 spinlock_t *lock;
352 unsigned long val, *blink_leds, *blink_delay;
353
354 mem_r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
355 if (!mem_r)
356 return -EINVAL;
357
358 mem = devm_ioremap_resource(dev, mem_r);
359 if (IS_ERR(mem))
360 return PTR_ERR(mem);
361
362 lock = devm_kzalloc(dev, sizeof(*lock), GFP_KERNEL);
363 if (!lock)
364 return -ENOMEM;
365
366 blink_leds = devm_kzalloc(dev, sizeof(*blink_leds), GFP_KERNEL);
367 if (!blink_leds)
368 return -ENOMEM;
369
370 blink_delay = devm_kzalloc(dev, sizeof(*blink_delay), GFP_KERNEL);
371 if (!blink_delay)
372 return -ENOMEM;
373
374 spin_lock_init(lock);
375
376 bcm6328_led_write(mem + BCM6328_REG_HWDIS, ~0);
377 bcm6328_led_write(mem + BCM6328_REG_LNKACTSEL_HI, 0);
378 bcm6328_led_write(mem + BCM6328_REG_LNKACTSEL_LO, 0);
379
380 val = bcm6328_led_read(mem + BCM6328_REG_INIT);
381 val &= ~(BCM6328_INIT_MASK);
382 if (of_property_read_bool(np, "brcm,serial-leds"))
383 val |= BCM6328_SERIAL_LED_EN;
384 if (of_property_read_bool(np, "brcm,serial-mux"))
385 val |= BCM6328_SERIAL_LED_MUX;
386 if (of_property_read_bool(np, "brcm,serial-clk-low"))
387 val |= BCM6328_SERIAL_LED_CLK_NPOL;
388 if (!of_property_read_bool(np, "brcm,serial-dat-low"))
389 val |= BCM6328_SERIAL_LED_DATA_PPOL;
390 if (!of_property_read_bool(np, "brcm,serial-shift-inv"))
391 val |= BCM6328_SERIAL_LED_SHIFT_DIR;
392 bcm6328_led_write(mem + BCM6328_REG_INIT, val);
393
394 for_each_available_child_of_node(np, child) {
395 int rc;
396 u32 reg;
397
398 if (of_property_read_u32(child, "reg", ®))
399 continue;
400
401 if (reg >= BCM6328_LED_MAX_COUNT) {
402 dev_err(dev, "invalid LED (%u >= %d)\n", reg,
403 BCM6328_LED_MAX_COUNT);
404 continue;
405 }
406
407 if (of_property_read_bool(child, "brcm,hardware-controlled"))
408 rc = bcm6328_hwled(dev, child, reg, mem, lock);
409 else
410 rc = bcm6328_led(dev, child, reg, mem, lock,
411 blink_leds, blink_delay);
412
413 if (rc < 0) {
414 of_node_put(child);
415 return rc;
416 }
417 }
418
419 return 0;
420}
421
422static const struct of_device_id bcm6328_leds_of_match[] = {
423 { .compatible = "brcm,bcm6328-leds", },
424 { },
425};
426MODULE_DEVICE_TABLE(of, bcm6328_leds_of_match);
427
428static struct platform_driver bcm6328_leds_driver = {
429 .probe = bcm6328_leds_probe,
430 .driver = {
431 .name = "leds-bcm6328",
432 .of_match_table = bcm6328_leds_of_match,
433 },
434};
435
436module_platform_driver(bcm6328_leds_driver);
437
438MODULE_AUTHOR("Álvaro Fernández Rojas <noltari@gmail.com>");
439MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
440MODULE_DESCRIPTION("LED driver for BCM6328 controllers");
441MODULE_LICENSE("GPL v2");
442MODULE_ALIAS("platform:leds-bcm6328");
443
