1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Driver for BCM6328 memory-mapped LEDs, based on leds-syscon.c |
4 | * |
5 | * Copyright 2015 Álvaro Fernández Rojas <noltari@gmail.com> |
6 | * Copyright 2015 Jonas Gorski <jogo@openwrt.org> |
7 | */ |
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 | |
28 | #define BCM6328_LED_BLINK_DELAYS 2 |
29 | #define BCM6328_LED_BLINK_MS 20 |
30 | |
31 | #define BCM6328_LED_BLINK_MASK 0x3f |
32 | #define BCM6328_LED_BLINK1_SHIFT 0 |
33 | #define BCM6328_LED_BLINK1_MASK (BCM6328_LED_BLINK_MASK << \ |
34 | BCM6328_LED_BLINK1_SHIFT) |
35 | #define BCM6328_LED_BLINK2_SHIFT 6 |
36 | #define BCM6328_LED_BLINK2_MASK (BCM6328_LED_BLINK_MASK << \ |
37 | BCM6328_LED_BLINK2_SHIFT) |
38 | #define BCM6328_SERIAL_LED_EN BIT(12) |
39 | #define BCM6328_SERIAL_LED_MUX BIT(13) |
40 | #define BCM6328_SERIAL_LED_CLK_NPOL BIT(14) |
41 | #define BCM6328_SERIAL_LED_DATA_PPOL BIT(15) |
42 | #define BCM6328_SERIAL_LED_SHIFT_DIR BIT(16) |
43 | #define BCM6328_LED_SHIFT_TEST BIT(30) |
44 | #define BCM6328_LED_TEST BIT(31) |
45 | #define BCM6328_INIT_MASK (BCM6328_SERIAL_LED_EN | \ |
46 | BCM6328_SERIAL_LED_MUX | \ |
47 | BCM6328_SERIAL_LED_CLK_NPOL | \ |
48 | BCM6328_SERIAL_LED_DATA_PPOL | \ |
49 | BCM6328_SERIAL_LED_SHIFT_DIR) |
50 | |
51 | #define BCM6328_LED_MODE_MASK 3 |
52 | #define BCM6328_LED_MODE_ON 0 |
53 | #define BCM6328_LED_MODE_BLINK1 1 |
54 | #define BCM6328_LED_MODE_BLINK2 2 |
55 | #define BCM6328_LED_MODE_OFF 3 |
56 | #define BCM6328_LED_SHIFT(X) ((X) << 1) |
57 | |
58 | /** |
59 | * struct bcm6328_led - state container for bcm6328 based LEDs |
60 | * @cdev: LED class device for this LED |
61 | * @mem: memory resource |
62 | * @lock: memory lock |
63 | * @pin: LED pin number |
64 | * @blink_leds: blinking LEDs |
65 | * @blink_delay: blinking delay |
66 | * @active_low: LED is active low |
67 | */ |
68 | struct bcm6328_led { |
69 | struct led_classdev cdev; |
70 | void __iomem *mem; |
71 | spinlock_t *lock; |
72 | unsigned long pin; |
73 | unsigned long *blink_leds; |
74 | unsigned long *blink_delay; |
75 | bool active_low; |
76 | }; |
77 | |
78 | static void bcm6328_led_write(void __iomem *reg, unsigned long data) |
79 | { |
80 | #ifdef CONFIG_CPU_BIG_ENDIAN |
81 | iowrite32be(data, reg); |
82 | #else |
83 | writel(val: data, addr: reg); |
84 | #endif |
85 | } |
86 | |
87 | static unsigned long bcm6328_led_read(void __iomem *reg) |
88 | { |
89 | #ifdef CONFIG_CPU_BIG_ENDIAN |
90 | return ioread32be(reg); |
91 | #else |
92 | return readl(addr: reg); |
93 | #endif |
94 | } |
95 | |
96 | /* |
97 | * LEDMode 64 bits / 24 LEDs |
98 | * bits [31:0] -> LEDs 8-23 |
99 | * bits [47:32] -> LEDs 0-7 |
100 | * bits [63:48] -> unused |
101 | */ |
102 | static unsigned long bcm6328_pin2shift(unsigned long pin) |
103 | { |
104 | if (pin < 8) |
105 | return pin + 16; /* LEDs 0-7 (bits 47:32) */ |
106 | else |
107 | return pin - 8; /* LEDs 8-23 (bits 31:0) */ |
108 | } |
109 | |
110 | static void bcm6328_led_mode(struct bcm6328_led *led, unsigned long value) |
111 | { |
112 | void __iomem *mode; |
113 | unsigned long val, shift; |
114 | |
115 | shift = bcm6328_pin2shift(pin: led->pin); |
116 | if (shift / 16) |
117 | mode = led->mem + BCM6328_REG_MODE_HI; |
118 | else |
119 | mode = led->mem + BCM6328_REG_MODE_LO; |
120 | |
121 | val = bcm6328_led_read(reg: mode); |
122 | val &= ~(BCM6328_LED_MODE_MASK << BCM6328_LED_SHIFT(shift % 16)); |
123 | val |= (value << BCM6328_LED_SHIFT(shift % 16)); |
124 | bcm6328_led_write(reg: mode, data: val); |
125 | } |
126 | |
127 | static void bcm6328_led_set(struct led_classdev *led_cdev, |
128 | enum led_brightness value) |
129 | { |
130 | struct bcm6328_led *led = |
131 | container_of(led_cdev, struct bcm6328_led, cdev); |
132 | unsigned long flags; |
133 | |
134 | spin_lock_irqsave(led->lock, flags); |
135 | |
136 | /* Remove LED from cached HW blinking intervals */ |
137 | led->blink_leds[0] &= ~BIT(led->pin); |
138 | led->blink_leds[1] &= ~BIT(led->pin); |
139 | |
140 | /* Set LED on/off */ |
141 | if ((led->active_low && value == LED_OFF) || |
142 | (!led->active_low && value != LED_OFF)) |
143 | bcm6328_led_mode(led, BCM6328_LED_MODE_ON); |
144 | else |
145 | bcm6328_led_mode(led, BCM6328_LED_MODE_OFF); |
146 | |
147 | spin_unlock_irqrestore(lock: led->lock, flags); |
148 | } |
149 | |
150 | static unsigned long bcm6328_blink_delay(unsigned long delay) |
151 | { |
152 | unsigned long bcm6328_delay; |
153 | |
154 | bcm6328_delay = delay + BCM6328_LED_BLINK_MS / 2; |
155 | bcm6328_delay = bcm6328_delay / BCM6328_LED_BLINK_MS; |
156 | if (bcm6328_delay == 0) |
157 | bcm6328_delay = 1; |
158 | |
159 | return bcm6328_delay; |
160 | } |
161 | |
162 | static int bcm6328_blink_set(struct led_classdev *led_cdev, |
163 | unsigned long *delay_on, unsigned long *delay_off) |
164 | { |
165 | struct bcm6328_led *led = |
166 | container_of(led_cdev, struct bcm6328_led, cdev); |
167 | unsigned long delay, flags; |
168 | int rc; |
169 | |
170 | if (!*delay_on) |
171 | *delay_on = BCM6328_LED_DEF_DELAY; |
172 | if (!*delay_off) |
173 | *delay_off = BCM6328_LED_DEF_DELAY; |
174 | |
175 | delay = bcm6328_blink_delay(delay: *delay_on); |
176 | if (delay != bcm6328_blink_delay(delay: *delay_off)) { |
177 | dev_dbg(led_cdev->dev, |
178 | "fallback to soft blinking (delay_on != delay_off)\n" ); |
179 | return -EINVAL; |
180 | } |
181 | |
182 | if (delay > BCM6328_LED_BLINK_MASK) { |
183 | dev_dbg(led_cdev->dev, |
184 | "fallback to soft blinking (delay > %ums)\n" , |
185 | BCM6328_LED_BLINK_MASK * BCM6328_LED_BLINK_MS); |
186 | return -EINVAL; |
187 | } |
188 | |
189 | spin_lock_irqsave(led->lock, flags); |
190 | /* |
191 | * Check if any of the two configurable HW blinking intervals is |
192 | * available: |
193 | * 1. No LEDs assigned to the HW blinking interval. |
194 | * 2. Only this LED is assigned to the HW blinking interval. |
195 | * 3. LEDs with the same delay assigned. |
196 | */ |
197 | if (led->blink_leds[0] == 0 || |
198 | led->blink_leds[0] == BIT(led->pin) || |
199 | led->blink_delay[0] == delay) { |
200 | unsigned long val; |
201 | |
202 | /* Add LED to the first HW blinking interval cache */ |
203 | led->blink_leds[0] |= BIT(led->pin); |
204 | |
205 | /* Remove LED from the second HW blinking interval cache */ |
206 | led->blink_leds[1] &= ~BIT(led->pin); |
207 | |
208 | /* Cache first HW blinking interval delay */ |
209 | led->blink_delay[0] = delay; |
210 | |
211 | /* Update the delay for the first HW blinking interval */ |
212 | val = bcm6328_led_read(reg: led->mem + BCM6328_REG_INIT); |
213 | val &= ~BCM6328_LED_BLINK1_MASK; |
214 | val |= (delay << BCM6328_LED_BLINK1_SHIFT); |
215 | bcm6328_led_write(reg: led->mem + BCM6328_REG_INIT, data: val); |
216 | |
217 | /* Set the LED to first HW blinking interval */ |
218 | bcm6328_led_mode(led, BCM6328_LED_MODE_BLINK1); |
219 | |
220 | rc = 0; |
221 | } else if (led->blink_leds[1] == 0 || |
222 | led->blink_leds[1] == BIT(led->pin) || |
223 | led->blink_delay[1] == delay) { |
224 | unsigned long val; |
225 | |
226 | /* Remove LED from the first HW blinking interval */ |
227 | led->blink_leds[0] &= ~BIT(led->pin); |
228 | |
229 | /* Add LED to the second HW blinking interval */ |
230 | led->blink_leds[1] |= BIT(led->pin); |
231 | |
232 | /* Cache second HW blinking interval delay */ |
233 | led->blink_delay[1] = delay; |
234 | |
235 | /* Update the delay for the second HW blinking interval */ |
236 | val = bcm6328_led_read(reg: led->mem + BCM6328_REG_INIT); |
237 | val &= ~BCM6328_LED_BLINK2_MASK; |
238 | val |= (delay << BCM6328_LED_BLINK2_SHIFT); |
239 | bcm6328_led_write(reg: led->mem + BCM6328_REG_INIT, data: val); |
240 | |
241 | /* Set the LED to second HW blinking interval */ |
242 | bcm6328_led_mode(led, BCM6328_LED_MODE_BLINK2); |
243 | |
244 | rc = 0; |
245 | } else { |
246 | dev_dbg(led_cdev->dev, |
247 | "fallback to soft blinking (delay already set)\n" ); |
248 | rc = -EINVAL; |
249 | } |
250 | spin_unlock_irqrestore(lock: led->lock, flags); |
251 | |
252 | return rc; |
253 | } |
254 | |
255 | static int bcm6328_hwled(struct device *dev, struct device_node *nc, u32 reg, |
256 | void __iomem *mem, spinlock_t *lock) |
257 | { |
258 | int i, cnt; |
259 | unsigned long flags, val; |
260 | |
261 | spin_lock_irqsave(lock, flags); |
262 | val = bcm6328_led_read(reg: mem + BCM6328_REG_HWDIS); |
263 | val &= ~BIT(reg); |
264 | bcm6328_led_write(reg: mem + BCM6328_REG_HWDIS, data: val); |
265 | spin_unlock_irqrestore(lock, flags); |
266 | |
267 | /* Only LEDs 0-7 can be activity/link controlled */ |
268 | if (reg >= 8) |
269 | return 0; |
270 | |
271 | cnt = of_property_count_elems_of_size(np: nc, propname: "brcm,link-signal-sources" , |
272 | elem_size: sizeof(u32)); |
273 | for (i = 0; i < cnt; i++) { |
274 | u32 sel; |
275 | void __iomem *addr; |
276 | |
277 | if (reg < 4) |
278 | addr = mem + BCM6328_REG_LNKACTSEL_LO; |
279 | else |
280 | addr = mem + BCM6328_REG_LNKACTSEL_HI; |
281 | |
282 | of_property_read_u32_index(np: nc, propname: "brcm,link-signal-sources" , index: i, |
283 | out_value: &sel); |
284 | |
285 | if (reg / 4 != sel / 4) { |
286 | dev_warn(dev, "invalid link signal source\n" ); |
287 | continue; |
288 | } |
289 | |
290 | spin_lock_irqsave(lock, flags); |
291 | val = bcm6328_led_read(reg: addr); |
292 | val |= (BIT(reg % 4) << (((sel % 4) * 4) + 16)); |
293 | bcm6328_led_write(reg: addr, data: val); |
294 | spin_unlock_irqrestore(lock, flags); |
295 | } |
296 | |
297 | cnt = of_property_count_elems_of_size(np: nc, |
298 | propname: "brcm,activity-signal-sources" , |
299 | elem_size: sizeof(u32)); |
300 | for (i = 0; i < cnt; i++) { |
301 | u32 sel; |
302 | void __iomem *addr; |
303 | |
304 | if (reg < 4) |
305 | addr = mem + BCM6328_REG_LNKACTSEL_LO; |
306 | else |
307 | addr = mem + BCM6328_REG_LNKACTSEL_HI; |
308 | |
309 | of_property_read_u32_index(np: nc, propname: "brcm,activity-signal-sources" , |
310 | index: i, out_value: &sel); |
311 | |
312 | if (reg / 4 != sel / 4) { |
313 | dev_warn(dev, "invalid activity signal source\n" ); |
314 | continue; |
315 | } |
316 | |
317 | spin_lock_irqsave(lock, flags); |
318 | val = bcm6328_led_read(reg: addr); |
319 | val |= (BIT(reg % 4) << ((sel % 4) * 4)); |
320 | bcm6328_led_write(reg: addr, data: val); |
321 | spin_unlock_irqrestore(lock, flags); |
322 | } |
323 | |
324 | return 0; |
325 | } |
326 | |
327 | static int bcm6328_led(struct device *dev, struct device_node *nc, u32 reg, |
328 | void __iomem *mem, spinlock_t *lock, |
329 | unsigned long *blink_leds, unsigned long *blink_delay) |
330 | { |
331 | struct led_init_data init_data = {}; |
332 | struct bcm6328_led *led; |
333 | enum led_default_state state; |
334 | unsigned long val, shift; |
335 | void __iomem *mode; |
336 | int rc; |
337 | |
338 | led = devm_kzalloc(dev, size: sizeof(*led), GFP_KERNEL); |
339 | if (!led) |
340 | return -ENOMEM; |
341 | |
342 | led->pin = reg; |
343 | led->mem = mem; |
344 | led->lock = lock; |
345 | led->blink_leds = blink_leds; |
346 | led->blink_delay = blink_delay; |
347 | |
348 | if (of_property_read_bool(np: nc, propname: "active-low" )) |
349 | led->active_low = true; |
350 | |
351 | init_data.fwnode = of_fwnode_handle(nc); |
352 | |
353 | state = led_init_default_state_get(fwnode: init_data.fwnode); |
354 | switch (state) { |
355 | case LEDS_DEFSTATE_ON: |
356 | led->cdev.brightness = LED_FULL; |
357 | break; |
358 | case LEDS_DEFSTATE_KEEP: |
359 | shift = bcm6328_pin2shift(pin: led->pin); |
360 | if (shift / 16) |
361 | mode = mem + BCM6328_REG_MODE_HI; |
362 | else |
363 | mode = mem + BCM6328_REG_MODE_LO; |
364 | |
365 | val = bcm6328_led_read(reg: mode) >> BCM6328_LED_SHIFT(shift % 16); |
366 | val &= BCM6328_LED_MODE_MASK; |
367 | if ((led->active_low && val == BCM6328_LED_MODE_OFF) || |
368 | (!led->active_low && val == BCM6328_LED_MODE_ON)) |
369 | led->cdev.brightness = LED_FULL; |
370 | else |
371 | led->cdev.brightness = LED_OFF; |
372 | break; |
373 | default: |
374 | led->cdev.brightness = LED_OFF; |
375 | } |
376 | |
377 | bcm6328_led_set(led_cdev: &led->cdev, value: led->cdev.brightness); |
378 | |
379 | led->cdev.brightness_set = bcm6328_led_set; |
380 | led->cdev.blink_set = bcm6328_blink_set; |
381 | |
382 | rc = devm_led_classdev_register_ext(parent: dev, led_cdev: &led->cdev, init_data: &init_data); |
383 | if (rc < 0) |
384 | return rc; |
385 | |
386 | dev_dbg(dev, "registered LED %s\n" , led->cdev.name); |
387 | |
388 | return 0; |
389 | } |
390 | |
391 | static int bcm6328_leds_probe(struct platform_device *pdev) |
392 | { |
393 | struct device *dev = &pdev->dev; |
394 | struct device_node *np = dev_of_node(dev: &pdev->dev); |
395 | struct device_node *child; |
396 | void __iomem *mem; |
397 | spinlock_t *lock; /* memory lock */ |
398 | unsigned long val, *blink_leds, *blink_delay; |
399 | |
400 | mem = devm_platform_ioremap_resource(pdev, index: 0); |
401 | if (IS_ERR(ptr: mem)) |
402 | return PTR_ERR(ptr: mem); |
403 | |
404 | lock = devm_kzalloc(dev, size: sizeof(*lock), GFP_KERNEL); |
405 | if (!lock) |
406 | return -ENOMEM; |
407 | |
408 | blink_leds = devm_kcalloc(dev, BCM6328_LED_BLINK_DELAYS, |
409 | size: sizeof(*blink_leds), GFP_KERNEL); |
410 | if (!blink_leds) |
411 | return -ENOMEM; |
412 | |
413 | blink_delay = devm_kcalloc(dev, BCM6328_LED_BLINK_DELAYS, |
414 | size: sizeof(*blink_delay), GFP_KERNEL); |
415 | if (!blink_delay) |
416 | return -ENOMEM; |
417 | |
418 | spin_lock_init(lock); |
419 | |
420 | bcm6328_led_write(reg: mem + BCM6328_REG_HWDIS, data: ~0); |
421 | bcm6328_led_write(reg: mem + BCM6328_REG_LNKACTSEL_HI, data: 0); |
422 | bcm6328_led_write(reg: mem + BCM6328_REG_LNKACTSEL_LO, data: 0); |
423 | |
424 | val = bcm6328_led_read(reg: mem + BCM6328_REG_INIT); |
425 | val &= ~(BCM6328_INIT_MASK); |
426 | if (of_property_read_bool(np, propname: "brcm,serial-leds" )) |
427 | val |= BCM6328_SERIAL_LED_EN; |
428 | if (of_property_read_bool(np, propname: "brcm,serial-mux" )) |
429 | val |= BCM6328_SERIAL_LED_MUX; |
430 | if (of_property_read_bool(np, propname: "brcm,serial-clk-low" )) |
431 | val |= BCM6328_SERIAL_LED_CLK_NPOL; |
432 | if (!of_property_read_bool(np, propname: "brcm,serial-dat-low" )) |
433 | val |= BCM6328_SERIAL_LED_DATA_PPOL; |
434 | if (!of_property_read_bool(np, propname: "brcm,serial-shift-inv" )) |
435 | val |= BCM6328_SERIAL_LED_SHIFT_DIR; |
436 | bcm6328_led_write(reg: mem + BCM6328_REG_INIT, data: val); |
437 | |
438 | for_each_available_child_of_node(np, child) { |
439 | int rc; |
440 | u32 reg; |
441 | |
442 | if (of_property_read_u32(np: child, propname: "reg" , out_value: ®)) |
443 | continue; |
444 | |
445 | if (reg >= BCM6328_LED_MAX_COUNT) { |
446 | dev_err(dev, "invalid LED (%u >= %d)\n" , reg, |
447 | BCM6328_LED_MAX_COUNT); |
448 | continue; |
449 | } |
450 | |
451 | if (of_property_read_bool(np: child, propname: "brcm,hardware-controlled" )) |
452 | rc = bcm6328_hwled(dev, nc: child, reg, mem, lock); |
453 | else |
454 | rc = bcm6328_led(dev, nc: child, reg, mem, lock, |
455 | blink_leds, blink_delay); |
456 | |
457 | if (rc < 0) { |
458 | of_node_put(node: child); |
459 | return rc; |
460 | } |
461 | } |
462 | |
463 | return 0; |
464 | } |
465 | |
466 | static const struct of_device_id bcm6328_leds_of_match[] = { |
467 | { .compatible = "brcm,bcm6328-leds" , }, |
468 | { }, |
469 | }; |
470 | MODULE_DEVICE_TABLE(of, bcm6328_leds_of_match); |
471 | |
472 | static struct platform_driver bcm6328_leds_driver = { |
473 | .probe = bcm6328_leds_probe, |
474 | .driver = { |
475 | .name = "leds-bcm6328" , |
476 | .of_match_table = bcm6328_leds_of_match, |
477 | }, |
478 | }; |
479 | |
480 | module_platform_driver(bcm6328_leds_driver); |
481 | |
482 | MODULE_AUTHOR("Álvaro Fernández Rojas <noltari@gmail.com>" ); |
483 | MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>" ); |
484 | MODULE_DESCRIPTION("LED driver for BCM6328 controllers" ); |
485 | MODULE_LICENSE("GPL v2" ); |
486 | MODULE_ALIAS("platform:leds-bcm6328" ); |
487 | |