| // SPDX-License-Identifier: GPL-2.0-or-later |
| /* |
| * Driver for BCM6328 memory-mapped LEDs, based on leds-syscon.c |
| * |
| * Copyright 2015 Álvaro Fernández Rojas <noltari@gmail.com> |
| * Copyright 2015 Jonas Gorski <jogo@openwrt.org> |
| */ |
| #include <linux/io.h> |
| #include <linux/leds.h> |
| #include <linux/module.h> |
| #include <linux/of.h> |
| #include <linux/platform_device.h> |
| #include <linux/spinlock.h> |
| |
| #define BCM6328_REG_INIT 0x00 |
| #define BCM6328_REG_MODE_HI 0x04 |
| #define BCM6328_REG_MODE_LO 0x08 |
| #define BCM6328_REG_HWDIS 0x0c |
| #define BCM6328_REG_STROBE 0x10 |
| #define BCM6328_REG_LNKACTSEL_HI 0x14 |
| #define BCM6328_REG_LNKACTSEL_LO 0x18 |
| #define BCM6328_REG_RBACK 0x1c |
| #define BCM6328_REG_SERMUX 0x20 |
| |
| #define BCM6328_LED_MAX_COUNT 24 |
| #define BCM6328_LED_DEF_DELAY 500 |
| #define BCM6328_LED_INTERVAL_MS 20 |
| |
| #define BCM6328_LED_INTV_MASK 0x3f |
| #define BCM6328_LED_FAST_INTV_SHIFT 6 |
| #define BCM6328_LED_FAST_INTV_MASK (BCM6328_LED_INTV_MASK << \ |
| BCM6328_LED_FAST_INTV_SHIFT) |
| #define BCM6328_SERIAL_LED_EN BIT(12) |
| #define BCM6328_SERIAL_LED_MUX BIT(13) |
| #define BCM6328_SERIAL_LED_CLK_NPOL BIT(14) |
| #define BCM6328_SERIAL_LED_DATA_PPOL BIT(15) |
| #define BCM6328_SERIAL_LED_SHIFT_DIR BIT(16) |
| #define BCM6328_LED_SHIFT_TEST BIT(30) |
| #define BCM6328_LED_TEST BIT(31) |
| #define BCM6328_INIT_MASK (BCM6328_SERIAL_LED_EN | \ |
| BCM6328_SERIAL_LED_MUX | \ |
| BCM6328_SERIAL_LED_CLK_NPOL | \ |
| BCM6328_SERIAL_LED_DATA_PPOL | \ |
| BCM6328_SERIAL_LED_SHIFT_DIR) |
| |
| #define BCM6328_LED_MODE_MASK 3 |
| #define BCM6328_LED_MODE_ON 0 |
| #define BCM6328_LED_MODE_FAST 1 |
| #define BCM6328_LED_MODE_BLINK 2 |
| #define BCM6328_LED_MODE_OFF 3 |
| #define BCM6328_LED_SHIFT(X) ((X) << 1) |
| |
| /** |
| * struct bcm6328_led - state container for bcm6328 based LEDs |
| * @cdev: LED class device for this LED |
| * @mem: memory resource |
| * @lock: memory lock |
| * @pin: LED pin number |
| * @blink_leds: blinking LEDs |
| * @blink_delay: blinking delay |
| * @active_low: LED is active low |
| */ |
| struct bcm6328_led { |
| struct led_classdev cdev; |
| void __iomem *mem; |
| spinlock_t *lock; |
| unsigned long pin; |
| unsigned long *blink_leds; |
| unsigned long *blink_delay; |
| bool active_low; |
| }; |
| |
| static void bcm6328_led_write(void __iomem *reg, unsigned long data) |
| { |
| #ifdef CONFIG_CPU_BIG_ENDIAN |
| iowrite32be(data, reg); |
| #else |
| writel(data, reg); |
| #endif |
| } |
| |
| static unsigned long bcm6328_led_read(void __iomem *reg) |
| { |
| #ifdef CONFIG_CPU_BIG_ENDIAN |
| return ioread32be(reg); |
| #else |
| return readl(reg); |
| #endif |
| } |
| |
| /** |
| * LEDMode 64 bits / 24 LEDs |
| * bits [31:0] -> LEDs 8-23 |
| * bits [47:32] -> LEDs 0-7 |
| * bits [63:48] -> unused |
| */ |
| static unsigned long bcm6328_pin2shift(unsigned long pin) |
| { |
| if (pin < 8) |
| return pin + 16; /* LEDs 0-7 (bits 47:32) */ |
| else |
| return pin - 8; /* LEDs 8-23 (bits 31:0) */ |
| } |
| |
| static void bcm6328_led_mode(struct bcm6328_led *led, unsigned long value) |
| { |
| void __iomem *mode; |
| unsigned long val, shift; |
| |
| shift = bcm6328_pin2shift(led->pin); |
| if (shift / 16) |
| mode = led->mem + BCM6328_REG_MODE_HI; |
| else |
| mode = led->mem + BCM6328_REG_MODE_LO; |
| |
| val = bcm6328_led_read(mode); |
| val &= ~(BCM6328_LED_MODE_MASK << BCM6328_LED_SHIFT(shift % 16)); |
| val |= (value << BCM6328_LED_SHIFT(shift % 16)); |
| bcm6328_led_write(mode, val); |
| } |
| |
| static void bcm6328_led_set(struct led_classdev *led_cdev, |
| enum led_brightness value) |
| { |
| struct bcm6328_led *led = |
| container_of(led_cdev, struct bcm6328_led, cdev); |
| unsigned long flags; |
| |
| spin_lock_irqsave(led->lock, flags); |
| *(led->blink_leds) &= ~BIT(led->pin); |
| if ((led->active_low && value == LED_OFF) || |
| (!led->active_low && value != LED_OFF)) |
| bcm6328_led_mode(led, BCM6328_LED_MODE_ON); |
| else |
| bcm6328_led_mode(led, BCM6328_LED_MODE_OFF); |
| spin_unlock_irqrestore(led->lock, flags); |
| } |
| |
| static unsigned long bcm6328_blink_delay(unsigned long delay) |
| { |
| unsigned long bcm6328_delay; |
| |
| bcm6328_delay = delay + BCM6328_LED_INTERVAL_MS / 2; |
| bcm6328_delay = bcm6328_delay / BCM6328_LED_INTERVAL_MS; |
| if (bcm6328_delay == 0) |
| bcm6328_delay = 1; |
| |
| return bcm6328_delay; |
| } |
| |
| static int bcm6328_blink_set(struct led_classdev *led_cdev, |
| unsigned long *delay_on, unsigned long *delay_off) |
| { |
| struct bcm6328_led *led = |
| container_of(led_cdev, struct bcm6328_led, cdev); |
| unsigned long delay, flags; |
| int rc; |
| |
| if (!*delay_on) |
| *delay_on = BCM6328_LED_DEF_DELAY; |
| if (!*delay_off) |
| *delay_off = BCM6328_LED_DEF_DELAY; |
| |
| delay = bcm6328_blink_delay(*delay_on); |
| if (delay != bcm6328_blink_delay(*delay_off)) { |
| dev_dbg(led_cdev->dev, |
| "fallback to soft blinking (delay_on != delay_off)\n"); |
| return -EINVAL; |
| } |
| |
| if (delay > BCM6328_LED_INTV_MASK) { |
| dev_dbg(led_cdev->dev, |
| "fallback to soft blinking (delay > %ums)\n", |
| BCM6328_LED_INTV_MASK * BCM6328_LED_INTERVAL_MS); |
| return -EINVAL; |
| } |
| |
| spin_lock_irqsave(led->lock, flags); |
| if (*(led->blink_leds) == 0 || |
| *(led->blink_leds) == BIT(led->pin) || |
| *(led->blink_delay) == delay) { |
| unsigned long val; |
| |
| *(led->blink_leds) |= BIT(led->pin); |
| *(led->blink_delay) = delay; |
| |
| val = bcm6328_led_read(led->mem + BCM6328_REG_INIT); |
| val &= ~BCM6328_LED_FAST_INTV_MASK; |
| val |= (delay << BCM6328_LED_FAST_INTV_SHIFT); |
| bcm6328_led_write(led->mem + BCM6328_REG_INIT, val); |
| |
| bcm6328_led_mode(led, BCM6328_LED_MODE_BLINK); |
| rc = 0; |
| } else { |
| dev_dbg(led_cdev->dev, |
| "fallback to soft blinking (delay already set)\n"); |
| rc = -EINVAL; |
| } |
| spin_unlock_irqrestore(led->lock, flags); |
| |
| return rc; |
| } |
| |
| static int bcm6328_hwled(struct device *dev, struct device_node *nc, u32 reg, |
| void __iomem *mem, spinlock_t *lock) |
| { |
| int i, cnt; |
| unsigned long flags, val; |
| |
| spin_lock_irqsave(lock, flags); |
| val = bcm6328_led_read(mem + BCM6328_REG_HWDIS); |
| val &= ~BIT(reg); |
| bcm6328_led_write(mem + BCM6328_REG_HWDIS, val); |
| spin_unlock_irqrestore(lock, flags); |
| |
| /* Only LEDs 0-7 can be activity/link controlled */ |
| if (reg >= 8) |
| return 0; |
| |
| cnt = of_property_count_elems_of_size(nc, "brcm,link-signal-sources", |
| sizeof(u32)); |
| for (i = 0; i < cnt; i++) { |
| u32 sel; |
| void __iomem *addr; |
| |
| if (reg < 4) |
| addr = mem + BCM6328_REG_LNKACTSEL_LO; |
| else |
| addr = mem + BCM6328_REG_LNKACTSEL_HI; |
| |
| of_property_read_u32_index(nc, "brcm,link-signal-sources", i, |
| &sel); |
| |
| if (reg / 4 != sel / 4) { |
| dev_warn(dev, "invalid link signal source\n"); |
| continue; |
| } |
| |
| spin_lock_irqsave(lock, flags); |
| val = bcm6328_led_read(addr); |
| val |= (BIT(reg % 4) << (((sel % 4) * 4) + 16)); |
| bcm6328_led_write(addr, val); |
| spin_unlock_irqrestore(lock, flags); |
| } |
| |
| cnt = of_property_count_elems_of_size(nc, |
| "brcm,activity-signal-sources", |
| sizeof(u32)); |
| for (i = 0; i < cnt; i++) { |
| u32 sel; |
| void __iomem *addr; |
| |
| if (reg < 4) |
| addr = mem + BCM6328_REG_LNKACTSEL_LO; |
| else |
| addr = mem + BCM6328_REG_LNKACTSEL_HI; |
| |
| of_property_read_u32_index(nc, "brcm,activity-signal-sources", |
| i, &sel); |
| |
| if (reg / 4 != sel / 4) { |
| dev_warn(dev, "invalid activity signal source\n"); |
| continue; |
| } |
| |
| spin_lock_irqsave(lock, flags); |
| val = bcm6328_led_read(addr); |
| val |= (BIT(reg % 4) << ((sel % 4) * 4)); |
| bcm6328_led_write(addr, val); |
| spin_unlock_irqrestore(lock, flags); |
| } |
| |
| return 0; |
| } |
| |
| static int bcm6328_led(struct device *dev, struct device_node *nc, u32 reg, |
| void __iomem *mem, spinlock_t *lock, |
| unsigned long *blink_leds, unsigned long *blink_delay) |
| { |
| struct bcm6328_led *led; |
| const char *state; |
| int rc; |
| |
| led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL); |
| if (!led) |
| return -ENOMEM; |
| |
| led->pin = reg; |
| led->mem = mem; |
| led->lock = lock; |
| led->blink_leds = blink_leds; |
| led->blink_delay = blink_delay; |
| |
| if (of_property_read_bool(nc, "active-low")) |
| led->active_low = true; |
| |
| led->cdev.name = of_get_property(nc, "label", NULL) ? : nc->name; |
| led->cdev.default_trigger = of_get_property(nc, |
| "linux,default-trigger", |
| NULL); |
| |
| if (!of_property_read_string(nc, "default-state", &state)) { |
| if (!strcmp(state, "on")) { |
| led->cdev.brightness = LED_FULL; |
| } else if (!strcmp(state, "keep")) { |
| void __iomem *mode; |
| unsigned long val, shift; |
| |
| shift = bcm6328_pin2shift(led->pin); |
| if (shift / 16) |
| mode = mem + BCM6328_REG_MODE_HI; |
| else |
| mode = mem + BCM6328_REG_MODE_LO; |
| |
| val = bcm6328_led_read(mode) >> |
| BCM6328_LED_SHIFT(shift % 16); |
| val &= BCM6328_LED_MODE_MASK; |
| if ((led->active_low && val == BCM6328_LED_MODE_OFF) || |
| (!led->active_low && val == BCM6328_LED_MODE_ON)) |
| led->cdev.brightness = LED_FULL; |
| else |
| led->cdev.brightness = LED_OFF; |
| } else { |
| led->cdev.brightness = LED_OFF; |
| } |
| } else { |
| led->cdev.brightness = LED_OFF; |
| } |
| |
| bcm6328_led_set(&led->cdev, led->cdev.brightness); |
| |
| led->cdev.brightness_set = bcm6328_led_set; |
| led->cdev.blink_set = bcm6328_blink_set; |
| |
| rc = devm_led_classdev_register(dev, &led->cdev); |
| if (rc < 0) |
| return rc; |
| |
| dev_dbg(dev, "registered LED %s\n", led->cdev.name); |
| |
| return 0; |
| } |
| |
| static int bcm6328_leds_probe(struct platform_device *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| struct device_node *np = pdev->dev.of_node; |
| struct device_node *child; |
| struct resource *mem_r; |
| void __iomem *mem; |
| spinlock_t *lock; /* memory lock */ |
| unsigned long val, *blink_leds, *blink_delay; |
| |
| mem_r = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| if (!mem_r) |
| return -EINVAL; |
| |
| mem = devm_ioremap_resource(dev, mem_r); |
| if (IS_ERR(mem)) |
| return PTR_ERR(mem); |
| |
| lock = devm_kzalloc(dev, sizeof(*lock), GFP_KERNEL); |
| if (!lock) |
| return -ENOMEM; |
| |
| blink_leds = devm_kzalloc(dev, sizeof(*blink_leds), GFP_KERNEL); |
| if (!blink_leds) |
| return -ENOMEM; |
| |
| blink_delay = devm_kzalloc(dev, sizeof(*blink_delay), GFP_KERNEL); |
| if (!blink_delay) |
| return -ENOMEM; |
| |
| spin_lock_init(lock); |
| |
| bcm6328_led_write(mem + BCM6328_REG_HWDIS, ~0); |
| bcm6328_led_write(mem + BCM6328_REG_LNKACTSEL_HI, 0); |
| bcm6328_led_write(mem + BCM6328_REG_LNKACTSEL_LO, 0); |
| |
| val = bcm6328_led_read(mem + BCM6328_REG_INIT); |
| val &= ~(BCM6328_INIT_MASK); |
| if (of_property_read_bool(np, "brcm,serial-leds")) |
| val |= BCM6328_SERIAL_LED_EN; |
| if (of_property_read_bool(np, "brcm,serial-mux")) |
| val |= BCM6328_SERIAL_LED_MUX; |
| if (of_property_read_bool(np, "brcm,serial-clk-low")) |
| val |= BCM6328_SERIAL_LED_CLK_NPOL; |
| if (!of_property_read_bool(np, "brcm,serial-dat-low")) |
| val |= BCM6328_SERIAL_LED_DATA_PPOL; |
| if (!of_property_read_bool(np, "brcm,serial-shift-inv")) |
| val |= BCM6328_SERIAL_LED_SHIFT_DIR; |
| bcm6328_led_write(mem + BCM6328_REG_INIT, val); |
| |
| for_each_available_child_of_node(np, child) { |
| int rc; |
| u32 reg; |
| |
| if (of_property_read_u32(child, "reg", ®)) |
| continue; |
| |
| if (reg >= BCM6328_LED_MAX_COUNT) { |
| dev_err(dev, "invalid LED (%u >= %d)\n", reg, |
| BCM6328_LED_MAX_COUNT); |
| continue; |
| } |
| |
| if (of_property_read_bool(child, "brcm,hardware-controlled")) |
| rc = bcm6328_hwled(dev, child, reg, mem, lock); |
| else |
| rc = bcm6328_led(dev, child, reg, mem, lock, |
| blink_leds, blink_delay); |
| |
| if (rc < 0) { |
| of_node_put(child); |
| return rc; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static const struct of_device_id bcm6328_leds_of_match[] = { |
| { .compatible = "brcm,bcm6328-leds", }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, bcm6328_leds_of_match); |
| |
| static struct platform_driver bcm6328_leds_driver = { |
| .probe = bcm6328_leds_probe, |
| .driver = { |
| .name = "leds-bcm6328", |
| .of_match_table = bcm6328_leds_of_match, |
| }, |
| }; |
| |
| module_platform_driver(bcm6328_leds_driver); |
| |
| MODULE_AUTHOR("Álvaro Fernández Rojas <noltari@gmail.com>"); |
| MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>"); |
| MODULE_DESCRIPTION("LED driver for BCM6328 controllers"); |
| MODULE_LICENSE("GPL v2"); |
| MODULE_ALIAS("platform:leds-bcm6328"); |