// SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2021 Rafał Miłecki */ #include #include #include #include #include #include #include #include #include #include #define BCM63138_MAX_LEDS 32 #define BCM63138_MAX_BRIGHTNESS 9 #define BCM63138_LED_BITS 4 /* how many bits control a single LED */ #define BCM63138_LED_MASK ((1 << BCM63138_LED_BITS) - 1) /* 0xf */ #define BCM63138_LEDS_PER_REG (32 / BCM63138_LED_BITS) /* 8 */ #define BCM63138_GLB_CTRL 0x00 #define BCM63138_GLB_CTRL_SERIAL_LED_DATA_PPOL BIT(1) #define BCM63138_GLB_CTRL_SERIAL_LED_CLK_POL BIT(2) #define BCM63138_GLB_CTRL_SERIAL_LED_EN_POL BIT(3) #define BCM63138_GLB_CTRL_SERIAL_LED_MSB_FIRST BIT(4) #define BCM63138_MASK 0x04 #define BCM63138_HW_LED_EN 0x08 #define BCM63138_SERIAL_LED_SHIFT_SEL 0x0c #define BCM63138_FLASH_RATE_CTRL1 0x10 #define BCM63138_FLASH_RATE_CTRL2 0x14 #define BCM63138_FLASH_RATE_CTRL3 0x18 #define BCM63138_FLASH_RATE_CTRL4 0x1c #define BCM63138_BRIGHT_CTRL1 0x20 #define BCM63138_BRIGHT_CTRL2 0x24 #define BCM63138_BRIGHT_CTRL3 0x28 #define BCM63138_BRIGHT_CTRL4 0x2c #define BCM63138_POWER_LED_CFG 0x30 #define BCM63138_POWER_LUT_BASE0 0x34 /* -> b0 */ #define BCM63138_HW_POLARITY 0xb4 #define BCM63138_SW_DATA 0xb8 #define BCM63138_SW_POLARITY 0xbc #define BCM63138_PARALLEL_LED_POLARITY 0xc0 #define BCM63138_SERIAL_LED_POLARITY 0xc4 #define BCM63138_HW_LED_STATUS 0xc8 #define BCM63138_FLASH_CTRL_STATUS 0xcc #define BCM63138_FLASH_BRT_CTRL 0xd0 #define BCM63138_FLASH_P_LED_OUT_STATUS 0xd4 #define BCM63138_FLASH_S_LED_OUT_STATUS 0xd8 struct bcm63138_leds { struct device *dev; void __iomem *base; spinlock_t lock; }; struct bcm63138_led { struct bcm63138_leds *leds; struct led_classdev cdev; u32 pin; bool active_low; }; /* * I/O access */ static void bcm63138_leds_write(struct bcm63138_leds *leds, unsigned int reg, u32 data) { writel(data, leds->base + reg); } static unsigned long bcm63138_leds_read(struct bcm63138_leds *leds, unsigned int reg) { return readl(leds->base + reg); } static void bcm63138_leds_update_bits(struct bcm63138_leds *leds, unsigned int reg, u32 mask, u32 val) { WARN_ON(val & ~mask); bcm63138_leds_write(leds, reg, (bcm63138_leds_read(leds, reg) & ~mask) | (val & mask)); } /* * Helpers */ static void bcm63138_leds_set_flash_rate(struct bcm63138_leds *leds, struct bcm63138_led *led, u8 value) { int reg_offset = (led->pin >> fls((BCM63138_LEDS_PER_REG - 1))) * 4; int shift = (led->pin & (BCM63138_LEDS_PER_REG - 1)) * BCM63138_LED_BITS; bcm63138_leds_update_bits(leds, BCM63138_FLASH_RATE_CTRL1 + reg_offset, BCM63138_LED_MASK << shift, value << shift); } static void bcm63138_leds_set_bright(struct bcm63138_leds *leds, struct bcm63138_led *led, u8 value) { int reg_offset = (led->pin >> fls((BCM63138_LEDS_PER_REG - 1))) * 4; int shift = (led->pin & (BCM63138_LEDS_PER_REG - 1)) * BCM63138_LED_BITS; bcm63138_leds_update_bits(leds, BCM63138_BRIGHT_CTRL1 + reg_offset, BCM63138_LED_MASK << shift, value << shift); } static void bcm63138_leds_enable_led(struct bcm63138_leds *leds, struct bcm63138_led *led, enum led_brightness value) { u32 bit = BIT(led->pin); bcm63138_leds_update_bits(leds, BCM63138_SW_DATA, bit, value ? bit : 0); } /* * API callbacks */ static void bcm63138_leds_brightness_set(struct led_classdev *led_cdev, enum led_brightness value) { struct bcm63138_led *led = container_of(led_cdev, struct bcm63138_led, cdev); struct bcm63138_leds *leds = led->leds; guard(spinlock_irqsave)(&leds->lock); bcm63138_leds_enable_led(leds, led, value); if (!value) bcm63138_leds_set_flash_rate(leds, led, 0); else bcm63138_leds_set_bright(leds, led, value); } static int bcm63138_leds_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on, unsigned long *delay_off) { struct bcm63138_led *led = container_of(led_cdev, struct bcm63138_led, cdev); struct bcm63138_leds *leds = led->leds; u8 value; if (!*delay_on && !*delay_off) { *delay_on = 640; *delay_off = 640; } if (*delay_on != *delay_off) { dev_dbg(led_cdev->dev, "Blinking at unequal delays is not supported\n"); return -EINVAL; } switch (*delay_on) { case 1152 ... 1408: /* 1280 ms ± 10% */ value = 0x7; break; case 576 ... 704: /* 640 ms ± 10% */ value = 0x6; break; case 288 ... 352: /* 320 ms ± 10% */ value = 0x5; break; case 126 ... 154: /* 140 ms ± 10% */ value = 0x4; break; case 59 ... 72: /* 65 ms ± 10% */ value = 0x3; break; default: dev_dbg(led_cdev->dev, "Blinking delay value %lu is unsupported\n", *delay_on); return -EINVAL; } guard(spinlock_irqsave)(&leds->lock); bcm63138_leds_enable_led(leds, led, BCM63138_MAX_BRIGHTNESS); bcm63138_leds_set_flash_rate(leds, led, value); return 0; } /* * LED driver */ static void bcm63138_leds_create_led(struct bcm63138_leds *leds, struct device_node *np) { struct led_init_data init_data = { .fwnode = of_fwnode_handle(np), }; struct device *dev = leds->dev; struct bcm63138_led *led; struct pinctrl *pinctrl; u32 bit; int err; led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL); if (!led) { dev_err(dev, "Failed to alloc LED\n"); return; } led->leds = leds; if (of_property_read_u32(np, "reg", &led->pin)) { dev_err(dev, "Missing \"reg\" property in %pOF\n", np); goto err_free; } if (led->pin >= BCM63138_MAX_LEDS) { dev_err(dev, "Invalid \"reg\" value %d\n", led->pin); goto err_free; } led->active_low = of_property_read_bool(np, "active-low"); led->cdev.max_brightness = BCM63138_MAX_BRIGHTNESS; led->cdev.brightness_set = bcm63138_leds_brightness_set; led->cdev.blink_set = bcm63138_leds_blink_set; err = devm_led_classdev_register_ext(dev, &led->cdev, &init_data); if (err) { dev_err(dev, "Failed to register LED %pOF: %d\n", np, err); goto err_free; } pinctrl = devm_pinctrl_get_select_default(led->cdev.dev); if (IS_ERR(pinctrl) && PTR_ERR(pinctrl) != -ENODEV) { dev_warn(led->cdev.dev, "Failed to select %pOF pinctrl: %ld\n", np, PTR_ERR(pinctrl)); } bit = BIT(led->pin); bcm63138_leds_update_bits(leds, BCM63138_PARALLEL_LED_POLARITY, bit, led->active_low ? 0 : bit); bcm63138_leds_update_bits(leds, BCM63138_HW_LED_EN, bit, 0); bcm63138_leds_set_flash_rate(leds, led, 0); bcm63138_leds_enable_led(leds, led, led->cdev.brightness); return; err_free: devm_kfree(dev, led); } static int bcm63138_leds_probe(struct platform_device *pdev) { struct device_node *np = dev_of_node(&pdev->dev); struct device *dev = &pdev->dev; struct bcm63138_leds *leds; u32 shift_bits; leds = devm_kzalloc(dev, sizeof(*leds), GFP_KERNEL); if (!leds) return -ENOMEM; leds->dev = dev; leds->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(leds->base)) return PTR_ERR(leds->base); spin_lock_init(&leds->lock); /* If this property is not present, we use boot defaults */ if (!of_property_read_u32(np, "brcm,serial-shift-bits", &shift_bits)) { bcm63138_leds_write(leds, BCM63138_SERIAL_LED_SHIFT_SEL, GENMASK(shift_bits - 1, 0)); } bcm63138_leds_write(leds, BCM63138_GLB_CTRL, BCM63138_GLB_CTRL_SERIAL_LED_DATA_PPOL | BCM63138_GLB_CTRL_SERIAL_LED_EN_POL); bcm63138_leds_write(leds, BCM63138_HW_LED_EN, 0); bcm63138_leds_write(leds, BCM63138_SERIAL_LED_POLARITY, 0); bcm63138_leds_write(leds, BCM63138_PARALLEL_LED_POLARITY, 0); for_each_available_child_of_node_scoped(np, child) { bcm63138_leds_create_led(leds, child); } return 0; } static const struct of_device_id bcm63138_leds_of_match_table[] = { { .compatible = "brcm,bcm63138-leds", }, { }, }; static struct platform_driver bcm63138_leds_driver = { .probe = bcm63138_leds_probe, .driver = { .name = "leds-bcm63xxx", .of_match_table = bcm63138_leds_of_match_table, }, }; module_platform_driver(bcm63138_leds_driver); MODULE_AUTHOR("Rafał Miłecki"); MODULE_DESCRIPTION("Broadcom BCM63138 SoC LED driver"); MODULE_LICENSE("GPL"); MODULE_DEVICE_TABLE(of, bcm63138_leds_of_match_table);