This adds support for the LED controller on Broadcom's BCM6328.
Signed-off-by: Álvaro Fernández Rojas <noltari@xxxxxxxxx>
Signed-off-by: Jonas Gorski <jogo@xxxxxxxxxxx>
---
v5: introduce changes suggested by Jacek
- Set active_low true instead of 1.
v4: resend, no changes.
v3: introduce changes suggested by Jacek
- Revert compatible string to "brcm,bcm6328-leds".
- Add BCM6328_ prefix to macros.
- Rename blink_del to blink_delay.
v2: introduce changes suggested by Florian and Jonas.
- Improve Kconfig description.
- Remove unused imports.
- Fix bug in blink_set so it works for multiple LEDs.
- "brcm,link-selection" -> "brcm,link-signal-sources".
- "brcm,activity-selection" -> "brcm,activity-signal-sources".
- Use of_property_read_bool instead of of_get_property for booleans.
- Add MODULE_AUTHOR strings.
drivers/leds/Kconfig | 8 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-bcm6328.c | 413 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 422 insertions(+)
create mode 100644 drivers/leds/leds-bcm6328.c
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 966b960..caa8ee6 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -42,6 +42,14 @@ config LEDS_88PM860X
This option enables support for on-chip LED drivers found on Marvell
Semiconductor 88PM8606 PMIC.
+config LEDS_BCM6328
+ tristate "LED Support for Broadcom BCM6328"
+ depends on LEDS_CLASS
+ depends on OF
+ help
+ This option enables support for LEDs connected to the BCM6328
+ LED HW controller accessed via MMIO registers.
+
config LEDS_LM3530
tristate "LCD Backlight driver for LM3530"
depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index bf46093..309a46b 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o
# LED Platform Drivers
obj-$(CONFIG_LEDS_88PM860X) += leds-88pm860x.o
+obj-$(CONFIG_LEDS_BCM6328) += leds-bcm6328.o
obj-$(CONFIG_LEDS_BD2802) += leds-bd2802.o
obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o
obj-$(CONFIG_LEDS_LM3530) += leds-lm3530.o
diff --git a/drivers/leds/leds-bcm6328.c b/drivers/leds/leds-bcm6328.c
new file mode 100644
index 0000000..986fe1e
--- /dev/null
+++ b/drivers/leds/leds-bcm6328.c
@@ -0,0 +1,413 @@
+/*
+ * Driver for BCM6328 memory-mapped LEDs, based on leds-syscon.c
+ *
+ * Copyright 2015 Álvaro Fernández Rojas <noltari@xxxxxxxxx>
+ * Copyright 2015 Jonas Gorski <jogo@xxxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ */
+#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_LED_MODE_MASK 3
+#define BCM6328_LED_MODE_OFF 0
+#define BCM6328_LED_MODE_FAST 1
+#define BCM6328_LED_MODE_BLINK 2
+#define BCM6328_LED_MODE_ON 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)
+{
+ iowrite32be(data, reg);
+}
+
+static unsigned long bcm6328_led_read(void __iomem *reg)
+{
+ return ioread32be(reg);
+}
+
+/**
+ * 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_OFF);
+ else
+ bcm6328_led_mode(led, BCM6328_LED_MODE_ON);
+ spin_unlock_irqrestore(led->lock, flags);
+}
+
+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;
+
+ if (!*delay_on)
+ *delay_on = BCM6328_LED_DEF_DELAY;
+ if (!*delay_off)
+ *delay_off = BCM6328_LED_DEF_DELAY;
+
+ if (*delay_on != *delay_off) {
+ dev_dbg(led_cdev->dev,
+ "fallback to soft blinking (delay_on != delay_off)\n");
+ return -EINVAL;
+ }
+
+ delay = *delay_on / BCM6328_LED_INTERVAL_MS;
+ if (delay == 0)
+ delay = 1;
+ else 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);
+
+ spin_unlock_irqrestore(led->lock, flags);
+ } else {
+ spin_unlock_irqrestore(led->lock, flags);
+ dev_dbg(led_cdev->dev,
+ "fallback to soft blinking (delay already set)\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+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) << (((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) << ((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;
+ unsigned long flags;
+ 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)) {
+ spin_lock_irqsave(lock, flags);
+ if (!strcmp(state, "on")) {
+ led->cdev.brightness = LED_FULL;
+ bcm6328_led_mode(led, BCM6328_LED_MODE_ON);
+ } 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) >> (shift % 16);
+ val &= BCM6328_LED_MODE_MASK;
+ if (val == BCM6328_LED_MODE_ON)
+ led->cdev.brightness = LED_FULL;
+ else {
+ led->cdev.brightness = LED_OFF;
+ bcm6328_led_mode(led, BCM6328_LED_MODE_OFF);
+ }
+ } else {
+ led->cdev.brightness = LED_OFF;
+ bcm6328_led_mode(led, BCM6328_LED_MODE_OFF);
+ }
+ spin_unlock_irqrestore(lock, flags);
+ }
+
+ led->cdev.brightness_set = bcm6328_led_set;
+ led->cdev.blink_set = bcm6328_blink_set;
+
+ rc = 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;
+ 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_SERIAL_LED_EN;
+ if (of_property_read_bool(np, "brcm,serial-leds"))
+ val |= BCM6328_SERIAL_LED_EN;
+ 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 (>= %d)\n",
+ 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)
+ return rc;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id bcm6328_leds_of_match[] = {
+ { .compatible = "brcm,bcm6328-leds", },
+ { },
+};
+
+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@xxxxxxxxx>");
+MODULE_AUTHOR("Jonas Gorski <jogo@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("LED driver for BCM6328 controllers");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:leds-bcm6328");
--
1.9.1
--
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