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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Driver for BCM6328 memory-mapped LEDs, based on leds-syscon.c4 *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 0x0016#define BCM6328_REG_MODE_HI 0x0417#define BCM6328_REG_MODE_LO 0x0818#define BCM6328_REG_HWDIS 0x0c19#define BCM6328_REG_STROBE 0x1020#define BCM6328_REG_LNKACTSEL_HI 0x1421#define BCM6328_REG_LNKACTSEL_LO 0x1822#define BCM6328_REG_RBACK 0x1c23#define BCM6328_REG_SERMUX 0x2024 25#define BCM6328_LED_MAX_COUNT 2426#define BCM6328_LED_DEF_DELAY 50027 28#define BCM6328_LED_BLINK_DELAYS 229#define BCM6328_LED_BLINK_MS 2030 31#define BCM6328_LED_BLINK_MASK 0x3f32#define BCM6328_LED_BLINK1_SHIFT 033#define BCM6328_LED_BLINK1_MASK (BCM6328_LED_BLINK_MASK << \34 BCM6328_LED_BLINK1_SHIFT)35#define BCM6328_LED_BLINK2_SHIFT 636#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 352#define BCM6328_LED_MODE_ON 053#define BCM6328_LED_MODE_BLINK1 154#define BCM6328_LED_MODE_BLINK2 255#define BCM6328_LED_MODE_OFF 356#define BCM6328_LED_SHIFT(X) ((X) << 1)57 58/**59 * struct bcm6328_led - state container for bcm6328 based LEDs60 * @cdev: LED class device for this LED61 * @mem: memory resource62 * @lock: memory lock63 * @pin: LED pin number64 * @blink_leds: blinking LEDs65 * @blink_delay: blinking delay66 * @active_low: LED is active low67 */68struct 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 78static void bcm6328_led_write(void __iomem *reg, unsigned long data)79{80#ifdef CONFIG_CPU_BIG_ENDIAN81 iowrite32be(data, reg);82#else83 writel(data, reg);84#endif85}86 87static unsigned long bcm6328_led_read(void __iomem *reg)88{89#ifdef CONFIG_CPU_BIG_ENDIAN90 return ioread32be(reg);91#else92 return readl(reg);93#endif94}95 96/*97 * LEDMode 64 bits / 24 LEDs98 * bits [31:0] -> LEDs 8-2399 * bits [47:32] -> LEDs 0-7100 * bits [63:48] -> unused101 */102static unsigned long bcm6328_pin2shift(unsigned long pin)103{104 if (pin < 8)105 return pin + 16; /* LEDs 0-7 (bits 47:32) */106 else107 return pin - 8; /* LEDs 8-23 (bits 31:0) */108}109 110static 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(led->pin);116 if (shift / 16)117 mode = led->mem + BCM6328_REG_MODE_HI;118 else119 mode = led->mem + BCM6328_REG_MODE_LO;120 121 val = bcm6328_led_read(mode);122 val &= ~(BCM6328_LED_MODE_MASK << BCM6328_LED_SHIFT(shift % 16));123 val |= (value << BCM6328_LED_SHIFT(shift % 16));124 bcm6328_led_write(mode, val);125}126 127static 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 else145 bcm6328_led_mode(led, BCM6328_LED_MODE_OFF);146 147 spin_unlock_irqrestore(led->lock, flags);148}149 150static 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 162static 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_on);176 if (delay != bcm6328_blink_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 is192 * 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(led->mem + BCM6328_REG_INIT);213 val &= ~BCM6328_LED_BLINK1_MASK;214 val |= (delay << BCM6328_LED_BLINK1_SHIFT);215 bcm6328_led_write(led->mem + BCM6328_REG_INIT, 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(led->mem + BCM6328_REG_INIT);237 val &= ~BCM6328_LED_BLINK2_MASK;238 val |= (delay << BCM6328_LED_BLINK2_SHIFT);239 bcm6328_led_write(led->mem + BCM6328_REG_INIT, 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(led->lock, flags);251 252 return rc;253}254 255static 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(mem + BCM6328_REG_HWDIS);263 val &= ~BIT(reg);264 bcm6328_led_write(mem + BCM6328_REG_HWDIS, 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(nc, "brcm,link-signal-sources",272 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 else280 addr = mem + BCM6328_REG_LNKACTSEL_HI;281 282 of_property_read_u32_index(nc, "brcm,link-signal-sources", i,283 &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(addr);292 val |= (BIT(reg % 4) << (((sel % 4) * 4) + 16));293 bcm6328_led_write(addr, val);294 spin_unlock_irqrestore(lock, flags);295 }296 297 cnt = of_property_count_elems_of_size(nc,298 "brcm,activity-signal-sources",299 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 else307 addr = mem + BCM6328_REG_LNKACTSEL_HI;308 309 of_property_read_u32_index(nc, "brcm,activity-signal-sources",310 i, &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(addr);319 val |= (BIT(reg % 4) << ((sel % 4) * 4));320 bcm6328_led_write(addr, val);321 spin_unlock_irqrestore(lock, flags);322 }323 324 return 0;325}326 327static 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, 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(nc, "active-low"))349 led->active_low = true;350 351 init_data.fwnode = of_fwnode_handle(nc);352 353 state = led_init_default_state_get(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(led->pin);360 if (shift / 16)361 mode = mem + BCM6328_REG_MODE_HI;362 else363 mode = mem + BCM6328_REG_MODE_LO;364 365 val = bcm6328_led_read(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 else371 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.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(dev, &led->cdev, &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 391static int bcm6328_leds_probe(struct platform_device *pdev)392{393 struct device *dev = &pdev->dev;394 struct device_node *np = dev_of_node(&pdev->dev);395 void __iomem *mem;396 spinlock_t *lock; /* memory lock */397 unsigned long val, *blink_leds, *blink_delay;398 399 mem = devm_platform_ioremap_resource(pdev, 0);400 if (IS_ERR(mem))401 return PTR_ERR(mem);402 403 lock = devm_kzalloc(dev, sizeof(*lock), GFP_KERNEL);404 if (!lock)405 return -ENOMEM;406 407 blink_leds = devm_kcalloc(dev, BCM6328_LED_BLINK_DELAYS,408 sizeof(*blink_leds), GFP_KERNEL);409 if (!blink_leds)410 return -ENOMEM;411 412 blink_delay = devm_kcalloc(dev, BCM6328_LED_BLINK_DELAYS,413 sizeof(*blink_delay), GFP_KERNEL);414 if (!blink_delay)415 return -ENOMEM;416 417 spin_lock_init(lock);418 419 bcm6328_led_write(mem + BCM6328_REG_HWDIS, ~0);420 bcm6328_led_write(mem + BCM6328_REG_LNKACTSEL_HI, 0);421 bcm6328_led_write(mem + BCM6328_REG_LNKACTSEL_LO, 0);422 423 val = bcm6328_led_read(mem + BCM6328_REG_INIT);424 val &= ~(BCM6328_INIT_MASK);425 if (of_property_read_bool(np, "brcm,serial-leds"))426 val |= BCM6328_SERIAL_LED_EN;427 if (of_property_read_bool(np, "brcm,serial-mux"))428 val |= BCM6328_SERIAL_LED_MUX;429 if (of_property_read_bool(np, "brcm,serial-clk-low"))430 val |= BCM6328_SERIAL_LED_CLK_NPOL;431 if (!of_property_read_bool(np, "brcm,serial-dat-low"))432 val |= BCM6328_SERIAL_LED_DATA_PPOL;433 if (!of_property_read_bool(np, "brcm,serial-shift-inv"))434 val |= BCM6328_SERIAL_LED_SHIFT_DIR;435 bcm6328_led_write(mem + BCM6328_REG_INIT, val);436 437 for_each_available_child_of_node_scoped(np, child) {438 int rc;439 u32 reg;440 441 if (of_property_read_u32(child, "reg", ®))442 continue;443 444 if (reg >= BCM6328_LED_MAX_COUNT) {445 dev_err(dev, "invalid LED (%u >= %d)\n", reg,446 BCM6328_LED_MAX_COUNT);447 continue;448 }449 450 if (of_property_read_bool(child, "brcm,hardware-controlled"))451 rc = bcm6328_hwled(dev, child, reg, mem, lock);452 else453 rc = bcm6328_led(dev, child, reg, mem, lock,454 blink_leds, blink_delay);455 456 if (rc < 0)457 return rc;458 }459 460 return 0;461}462 463static const struct of_device_id bcm6328_leds_of_match[] = {464 { .compatible = "brcm,bcm6328-leds", },465 { },466};467MODULE_DEVICE_TABLE(of, bcm6328_leds_of_match);468 469static struct platform_driver bcm6328_leds_driver = {470 .probe = bcm6328_leds_probe,471 .driver = {472 .name = "leds-bcm6328",473 .of_match_table = bcm6328_leds_of_match,474 },475};476 477module_platform_driver(bcm6328_leds_driver);478 479MODULE_AUTHOR("Álvaro Fernández Rojas <noltari@gmail.com>");480MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");481MODULE_DESCRIPTION("LED driver for BCM6328 controllers");482MODULE_LICENSE("GPL v2");483MODULE_ALIAS("platform:leds-bcm6328");484