dm: led: add BCM6328 led driver

This driver is a simplified version of linux/drivers/leds/leds-bcm6328.c,
simplified to remove HW leds and blink fallbacks.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Álvaro Fernández Rojas 2017-05-07 20:10:24 +02:00 committed by Daniel Schwierzeck
parent 2791f8db5e
commit 28300dc526
4 changed files with 380 additions and 0 deletions

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@ -0,0 +1,106 @@
LEDs connected to Broadcom BCM6328 controller
This controller is present on BCM6318, BCM6328, BCM6362 and BCM63268.
In these SoCs it's possible to control LEDs both as GPIOs or by hardware.
However, on some devices there are Serial LEDs (LEDs connected to a 74x164
controller), which can either be controlled by software (exporting the 74x164
as spi-gpio. See Documentation/devicetree/bindings/gpio/gpio-74x164.txt), or
by hardware using this driver.
Some of these Serial LEDs are hardware controlled (e.g. ethernet LEDs) and
exporting the 74x164 as spi-gpio prevents those LEDs to be hardware
controlled, so the only chance to keep them working is by using this driver.
Required properties:
- compatible : should be "brcm,bcm6328-leds".
- #address-cells : must be 1.
- #size-cells : must be 0.
- reg : BCM6328 LED controller address and size.
Optional properties:
- brcm,serial-leds : Boolean, enables Serial LEDs.
Default : false
- brcm,serial-mux : Boolean, enables Serial LEDs multiplexing.
Default : false
- brcm,serial-clk-low : Boolean, makes clock signal active low.
Default : false
- brcm,serial-dat-low : Boolean, makes data signal active low.
Default : false
- brcm,serial-shift-inv : Boolean, inverts Serial LEDs shift direction.
Default : false
Each LED is represented as a sub-node of the brcm,bcm6328-leds device.
LED sub-node required properties:
- reg : LED pin number (only LEDs 0 to 23 are valid).
LED sub-node optional properties:
- label : see Documentation/devicetree/bindings/leds/common.txt
- active-low : Boolean, makes LED active low.
Default : false
Examples:
Scenario 1 : BCM6328 with 4 GPIO LEDs
leds0: led-controller@10000800 {
compatible = "brcm,bcm6328-leds";
#address-cells = <1>;
#size-cells = <0>;
reg = <0x10000800 0x24>;
alarm_red@2 {
reg = <2>;
active-low;
label = "red:alarm";
};
inet_green@3 {
reg = <3>;
active-low;
label = "green:inet";
};
power_green@4 {
reg = <4>;
active-low;
label = "green:power";
};
};
Scenario 2 : BCM63268 with Serial LEDs
leds0: led-controller@10001900 {
compatible = "brcm,bcm6328-leds";
#address-cells = <1>;
#size-cells = <0>;
reg = <0x10001900 0x24>;
brcm,serial-leds;
brcm,serial-dat-low;
brcm,serial-shift-inv;
inet_red@2 {
reg = <2>;
active-low;
label = "red:inet";
};
dsl_green@3 {
reg = <3>;
active-low;
label = "green:dsl";
};
usb_green@4 {
reg = <4>;
active-low;
label = "green:usb";
};
wps_green@7 {
reg = <7>;
active-low;
label = "green:wps";
};
inet_green@8 {
reg = <8>;
active-low;
label = "green:inet";
};
power_green@20 {
reg = <20>;
active-low;
label = "green:power";
};
};

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@ -9,6 +9,17 @@ config LED
can provide access to board-specific LEDs. Use of the device tree
for configuration is encouraged.
config LED_BCM6328
bool "LED Support for BCM6328"
depends on LED && ARCH_BMIPS
help
This option enables support for LEDs connected to the BCM6328
LED HW controller accessed via MMIO registers.
HW blinking is supported and up to 24 LEDs can be controlled.
All LEDs can blink at the same time but the delay is shared, which
means that if one LED is set to blink at 100ms and then a different
LED is set to blink at 200ms, both will blink at 200ms.
config LED_BLINK
bool "Support LED blinking"
depends on LED

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@ -6,4 +6,5 @@
#
obj-y += led-uclass.o
obj-$(CONFIG_LED_BCM6328) += led_bcm6328.o
obj-$(CONFIG_$(SPL_)LED_GPIO) += led_gpio.o

262
drivers/led/led_bcm6328.c Normal file
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@ -0,0 +1,262 @@
/*
* Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <led.h>
#include <asm/io.h>
#include <dm/lists.h>
#define LEDS_MAX 24
/* LED Init register */
#define LED_INIT_REG 0x00
#define LED_INIT_FASTINTV_MS 20
#define LED_INIT_FASTINTV_SHIFT 6
#define LED_INIT_FASTINTV_MASK (0x3f << LED_INIT_FASTINTV_SHIFT)
#define LED_INIT_SLEDEN_SHIFT 12
#define LED_INIT_SLEDEN_MASK (1 << LED_INIT_SLEDEN_SHIFT)
#define LED_INIT_SLEDMUX_SHIFT 13
#define LED_INIT_SLEDMUX_MASK (1 << LED_INIT_SLEDMUX_SHIFT)
#define LED_INIT_SLEDCLKNPOL_SHIFT 14
#define LED_INIT_SLEDCLKNPOL_MASK (1 << LED_INIT_SLEDCLKNPOL_SHIFT)
#define LED_INIT_SLEDDATAPPOL_SHIFT 15
#define LED_INIT_SLEDDATANPOL_MASK (1 << LED_INIT_SLEDDATAPPOL_SHIFT)
#define LED_INIT_SLEDSHIFTDIR_SHIFT 16
#define LED_INIT_SLEDSHIFTDIR_MASK (1 << LED_INIT_SLEDSHIFTDIR_SHIFT)
/* LED Mode registers */
#define LED_MODE_REG_HI 0x04
#define LED_MODE_REG_LO 0x08
#define LED_MODE_ON 0
#define LED_MODE_FAST 1
#define LED_MODE_BLINK 2
#define LED_MODE_OFF 3
#define LED_MODE_MASK 0x3
DECLARE_GLOBAL_DATA_PTR;
struct bcm6328_led_priv {
void __iomem *regs;
void __iomem *mode;
uint8_t shift;
bool active_low;
};
static unsigned long bcm6328_led_get_mode(struct bcm6328_led_priv *priv)
{
return ((readl_be(priv->mode) >> priv->shift) & LED_MODE_MASK);
}
static int bcm6328_led_set_mode(struct bcm6328_led_priv *priv, uint8_t mode)
{
clrsetbits_be32(priv->mode, (LED_MODE_MASK << priv->shift),
(mode << priv->shift));
return 0;
}
static enum led_state_t bcm6328_led_get_state(struct udevice *dev)
{
struct bcm6328_led_priv *priv = dev_get_priv(dev);
enum led_state_t state = LEDST_OFF;
switch (bcm6328_led_get_mode(priv)) {
#ifdef CONFIG_LED_BLINK
case LED_MODE_BLINK:
case LED_MODE_FAST:
state = LEDST_BLINK;
break;
#endif
case LED_MODE_OFF:
state = (priv->active_low ? LEDST_ON : LEDST_OFF);
break;
case LED_MODE_ON:
state = (priv->active_low ? LEDST_OFF : LEDST_ON);
break;
}
return state;
}
static int bcm6328_led_set_state(struct udevice *dev, enum led_state_t state)
{
struct bcm6328_led_priv *priv = dev_get_priv(dev);
unsigned long mode;
switch (state) {
#ifdef CONFIG_LED_BLINK
case LEDST_BLINK:
mode = LED_MODE_BLINK;
break;
#endif
case LEDST_OFF:
mode = (priv->active_low ? LED_MODE_ON : LED_MODE_OFF);
break;
case LEDST_ON:
mode = (priv->active_low ? LED_MODE_OFF : LED_MODE_ON);
break;
case LEDST_TOGGLE:
if (bcm6328_led_get_state(dev) == LEDST_OFF)
return bcm6328_led_set_state(dev, LEDST_ON);
else
return bcm6328_led_set_state(dev, LEDST_OFF);
break;
default:
return -ENOSYS;
}
return bcm6328_led_set_mode(priv, mode);
}
#ifdef CONFIG_LED_BLINK
static unsigned long bcm6328_blink_delay(int delay)
{
unsigned long bcm6328_delay = delay;
bcm6328_delay += (LED_INIT_FASTINTV_MS / 2);
bcm6328_delay /= LED_INIT_FASTINTV_MS;
bcm6328_delay <<= LED_INIT_FASTINTV_SHIFT;
if (bcm6328_delay > LED_INIT_FASTINTV_MASK)
return LED_INIT_FASTINTV_MASK;
else
return bcm6328_delay;
}
static int bcm6328_led_set_period(struct udevice *dev, int period_ms)
{
struct bcm6328_led_priv *priv = dev_get_priv(dev);
clrsetbits_be32(priv->regs + LED_INIT_REG, LED_INIT_FASTINTV_MASK,
bcm6328_blink_delay(period_ms));
return 0;
}
#endif
static const struct led_ops bcm6328_led_ops = {
.get_state = bcm6328_led_get_state,
.set_state = bcm6328_led_set_state,
#ifdef CONFIG_LED_BLINK
.set_period = bcm6328_led_set_period,
#endif
};
static int bcm6328_led_probe(struct udevice *dev)
{
struct led_uc_plat *uc_plat = dev_get_uclass_platdata(dev);
fdt_addr_t addr;
fdt_size_t size;
/* Top-level LED node */
if (!uc_plat->label) {
void __iomem *regs;
u32 set_bits = 0;
addr = dev_get_addr_size_index(dev, 0, &size);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
regs = ioremap(addr, size);
if (fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
"brcm,serial-leds"))
set_bits |= LED_INIT_SLEDEN_MASK;
if (fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
"brcm,serial-mux"))
set_bits |= LED_INIT_SLEDMUX_MASK;
if (fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
"brcm,serial-clk-low"))
set_bits |= LED_INIT_SLEDCLKNPOL_MASK;
if (!fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
"brcm,serial-dat-low"))
set_bits |= LED_INIT_SLEDDATANPOL_MASK;
if (!fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
"brcm,serial-shift-inv"))
set_bits |= LED_INIT_SLEDSHIFTDIR_MASK;
clrsetbits_be32(regs + LED_INIT_REG, ~0, set_bits);
} else {
struct bcm6328_led_priv *priv = dev_get_priv(dev);
unsigned int pin;
addr = dev_get_addr_size_index(dev_get_parent(dev), 0, &size);
if (addr == FDT_ADDR_T_NONE)
return -EINVAL;
pin = fdtdec_get_uint(gd->fdt_blob, dev_of_offset(dev), "reg",
LEDS_MAX);
if (pin >= LEDS_MAX)
return -EINVAL;
priv->regs = ioremap(addr, size);
if (pin < 8) {
/* LEDs 0-7 (bits 47:32) */
priv->mode = priv->regs + LED_MODE_REG_HI;
priv->shift = (pin << 1);
} else {
/* LEDs 8-23 (bits 31:0) */
priv->mode = priv->regs + LED_MODE_REG_LO;
priv->shift = ((pin - 8) << 1);
}
if (fdtdec_get_bool(gd->fdt_blob, dev_of_offset(dev),
"active-low"))
priv->active_low = true;
}
return 0;
}
static int bcm6328_led_bind(struct udevice *parent)
{
const void *blob = gd->fdt_blob;
int node;
for (node = fdt_first_subnode(blob, dev_of_offset(parent));
node > 0;
node = fdt_next_subnode(blob, node)) {
struct led_uc_plat *uc_plat;
struct udevice *dev;
const char *label;
int ret;
label = fdt_getprop(blob, node, "label", NULL);
if (!label) {
debug("%s: node %s has no label\n", __func__,
fdt_get_name(blob, node, NULL));
return -EINVAL;
}
ret = device_bind_driver_to_node(parent, "bcm6328-led",
fdt_get_name(blob, node, NULL),
node, &dev);
if (ret)
return ret;
uc_plat = dev_get_uclass_platdata(dev);
uc_plat->label = label;
}
return 0;
}
static const struct udevice_id bcm6328_led_ids[] = {
{ .compatible = "brcm,bcm6328-leds" },
{ /* sentinel */ }
};
U_BOOT_DRIVER(bcm6328_led) = {
.name = "bcm6328-led",
.id = UCLASS_LED,
.of_match = bcm6328_led_ids,
.ops = &bcm6328_led_ops,
.bind = bcm6328_led_bind,
.probe = bcm6328_led_probe,
.priv_auto_alloc_size = sizeof(struct bcm6328_led_priv),
};