linux/drivers/leds/leds-nic78bx.c
Hui Chun Ong 8338eab50f leds: Add user LED driver for NIC78bx device
Add the driver to support User LEDs on PXI Embedded Controller.

Signed-off-by: Hui Chun Ong <hui.chun.ong@ni.com>
Signed-off-by: Brad Mouring <brad.mouring@ni.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
2016-11-22 12:07:04 +01:00

210 lines
4.9 KiB
C

/*
* Copyright (C) 2016 National Instruments Corp.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/acpi.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#define NIC78BX_USER1_LED_MASK 0x3
#define NIC78BX_USER1_GREEN_LED BIT(0)
#define NIC78BX_USER1_YELLOW_LED BIT(1)
#define NIC78BX_USER2_LED_MASK 0xC
#define NIC78BX_USER2_GREEN_LED BIT(2)
#define NIC78BX_USER2_YELLOW_LED BIT(3)
#define NIC78BX_LOCK_REG_OFFSET 1
#define NIC78BX_LOCK_VALUE 0xA5
#define NIC78BX_UNLOCK_VALUE 0x5A
#define NIC78BX_USER_LED_IO_SIZE 2
struct nic78bx_led_data {
u16 io_base;
spinlock_t lock;
struct platform_device *pdev;
};
struct nic78bx_led {
u8 bit;
u8 mask;
struct nic78bx_led_data *data;
struct led_classdev cdev;
};
static inline struct nic78bx_led *to_nic78bx_led(struct led_classdev *cdev)
{
return container_of(cdev, struct nic78bx_led, cdev);
}
static void nic78bx_brightness_set(struct led_classdev *cdev,
enum led_brightness brightness)
{
struct nic78bx_led *nled = to_nic78bx_led(cdev);
unsigned long flags;
u8 value;
spin_lock_irqsave(&nled->data->lock, flags);
value = inb(nled->data->io_base);
if (brightness) {
value &= ~nled->mask;
value |= nled->bit;
} else {
value &= ~nled->bit;
}
outb(value, nled->data->io_base);
spin_unlock_irqrestore(&nled->data->lock, flags);
}
static enum led_brightness nic78bx_brightness_get(struct led_classdev *cdev)
{
struct nic78bx_led *nled = to_nic78bx_led(cdev);
unsigned long flags;
u8 value;
spin_lock_irqsave(&nled->data->lock, flags);
value = inb(nled->data->io_base);
spin_unlock_irqrestore(&nled->data->lock, flags);
return (value & nled->bit) ? 1 : LED_OFF;
}
static struct nic78bx_led nic78bx_leds[] = {
{
.bit = NIC78BX_USER1_GREEN_LED,
.mask = NIC78BX_USER1_LED_MASK,
.cdev = {
.name = "nilrt:green:user1",
.max_brightness = 1,
.brightness_set = nic78bx_brightness_set,
.brightness_get = nic78bx_brightness_get,
}
},
{
.bit = NIC78BX_USER1_YELLOW_LED,
.mask = NIC78BX_USER1_LED_MASK,
.cdev = {
.name = "nilrt:yellow:user1",
.max_brightness = 1,
.brightness_set = nic78bx_brightness_set,
.brightness_get = nic78bx_brightness_get,
}
},
{
.bit = NIC78BX_USER2_GREEN_LED,
.mask = NIC78BX_USER2_LED_MASK,
.cdev = {
.name = "nilrt:green:user2",
.max_brightness = 1,
.brightness_set = nic78bx_brightness_set,
.brightness_get = nic78bx_brightness_get,
}
},
{
.bit = NIC78BX_USER2_YELLOW_LED,
.mask = NIC78BX_USER2_LED_MASK,
.cdev = {
.name = "nilrt:yellow:user2",
.max_brightness = 1,
.brightness_set = nic78bx_brightness_set,
.brightness_get = nic78bx_brightness_get,
}
}
};
static int nic78bx_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct nic78bx_led_data *led_data;
struct resource *io_rc;
int ret, i;
led_data = devm_kzalloc(dev, sizeof(*led_data), GFP_KERNEL);
if (!led_data)
return -ENOMEM;
led_data->pdev = pdev;
platform_set_drvdata(pdev, led_data);
io_rc = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (!io_rc) {
dev_err(dev, "missing IO resources\n");
return -EINVAL;
}
if (resource_size(io_rc) < NIC78BX_USER_LED_IO_SIZE) {
dev_err(dev, "IO region too small\n");
return -EINVAL;
}
if (!devm_request_region(dev, io_rc->start, resource_size(io_rc),
KBUILD_MODNAME)) {
dev_err(dev, "failed to get IO region\n");
return -EBUSY;
}
led_data->io_base = io_rc->start;
spin_lock_init(&led_data->lock);
for (i = 0; i < ARRAY_SIZE(nic78bx_leds); i++) {
nic78bx_leds[i].data = led_data;
ret = devm_led_classdev_register(dev, &nic78bx_leds[i].cdev);
if (ret)
return ret;
}
/* Unlock LED register */
outb(NIC78BX_UNLOCK_VALUE,
led_data->io_base + NIC78BX_LOCK_REG_OFFSET);
return ret;
}
static int nic78bx_remove(struct platform_device *pdev)
{
struct nic78bx_led_data *led_data = platform_get_drvdata(pdev);
/* Lock LED register */
outb(NIC78BX_LOCK_VALUE,
led_data->io_base + NIC78BX_LOCK_REG_OFFSET);
return 0;
}
static const struct acpi_device_id led_device_ids[] = {
{"NIC78B3", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, led_device_ids);
static struct platform_driver led_driver = {
.probe = nic78bx_probe,
.remove = nic78bx_remove,
.driver = {
.name = KBUILD_MODNAME,
.acpi_match_table = ACPI_PTR(led_device_ids),
},
};
module_platform_driver(led_driver);
MODULE_DESCRIPTION("National Instruments PXI User LEDs driver");
MODULE_AUTHOR("Hui Chun Ong <hui.chun.ong@ni.com>");
MODULE_LICENSE("GPL");