// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
//
// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
// Copyright (c) 2018 Vadim Pasternak <[email protected]>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/platform_data/mlxreg.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
/* Codes for LEDs. */
#define MLXREG_LED_OFFSET_BLINK_3HZ 0x01 /* Offset from solid: 3Hz blink */
#define MLXREG_LED_OFFSET_BLINK_6HZ 0x02 /* Offset from solid: 6Hz blink */
#define MLXREG_LED_IS_OFF 0x00 /* Off */
#define MLXREG_LED_RED_SOLID 0x05 /* Solid red */
#define MLXREG_LED_GREEN_SOLID 0x0D /* Solid green */
#define MLXREG_LED_AMBER_SOLID 0x09 /* Solid amber */
#define MLXREG_LED_BLINK_3HZ 167 /* ~167 msec off/on - HW support */
#define MLXREG_LED_BLINK_6HZ 83 /* ~83 msec off/on - HW support */
#define MLXREG_LED_CAPABILITY_CLEAR GENMASK(31, 8) /* Clear mask */
/**
* struct mlxreg_led_data - led control data:
*
* @data: led configuration data;
* @led_cdev: led class data;
* @base_color: base led color (other colors have constant offset from base);
* @data_parent: pointer to private device control data of parent;
* @led_cdev_name: class device name
*/
struct mlxreg_led_data {
struct mlxreg_core_data *data;
struct led_classdev led_cdev;
u8 base_color;
void *data_parent;
char led_cdev_name[MLXREG_CORE_LABEL_MAX_SIZE];
};
#define cdev_to_priv(c) container_of(c, struct mlxreg_led_data, led_cdev)
/**
* struct mlxreg_led_priv_data - platform private data:
*
* @pdev: platform device;
* @pdata: platform data;
* @access_lock: mutex for attribute IO access;
*/
struct mlxreg_led_priv_data {
struct platform_device *pdev;
struct mlxreg_core_platform_data *pdata;
struct mutex access_lock; /* protect IO operations */
};
static int
mlxreg_led_store_hw(struct mlxreg_led_data *led_data, u8 vset)
{
struct mlxreg_led_priv_data *priv = led_data->data_parent;
struct mlxreg_core_platform_data *led_pdata = priv->pdata;
struct mlxreg_core_data *data = led_data->data;
u32 regval;
u32 nib;
int ret;
/*
* Each LED is controlled through low or high nibble of the relevant
* register byte. Register offset is specified by off parameter.
* Parameter vset provides color code: 0x0 for off, 0x5 for solid red,
* 0x6 for 3Hz blink red, 0xd for solid green, 0xe for 3Hz blink
* green.
* Parameter mask specifies which nibble is used for specific LED: mask
* 0xf0 - lower nibble is to be used (bits from 0 to 3), mask 0x0f -
* higher nibble (bits from 4 to 7).
*/
mutex_lock(&priv->access_lock);
ret = regmap_read(led_pdata->regmap, data->reg, ®val);
if (ret)
goto access_error;
nib = (ror32(data->mask, data->bit) == 0xf0) ? rol32(vset, data->bit) :
rol32(vset, data->bit + 4);
regval = (regval & data->mask) | nib;
ret = regmap_write(led_pdata->regmap, data->reg, regval);
access_error:
mutex_unlock(&priv->access_lock);
return ret;
}
static enum led_brightness
mlxreg_led_get_hw(struct mlxreg_led_data *led_data)
{
struct mlxreg_led_priv_data *priv = led_data->data_parent;
struct mlxreg_core_platform_data *led_pdata = priv->pdata;
struct mlxreg_core_data *data = led_data->data;
u32 regval;
int err;
/*
* Each LED is controlled through low or high nibble of the relevant
* register byte. Register offset is specified by off parameter.
* Parameter vset provides color code: 0x0 for off, 0x5 for solid red,
* 0x6 for 3Hz blink red, 0xd for solid green, 0xe for 3Hz blink
* green.
* Parameter mask specifies which nibble is used for specific LED: mask
* 0xf0 - lower nibble is to be used (bits from 0 to 3), mask 0x0f -
* higher nibble (bits from 4 to 7).
*/
err = regmap_read(led_pdata->regmap, data->reg, ®val);
if (err < 0) {
dev_warn(led_data->led_cdev.dev, "Failed to get current brightness, error: %d\n",
err);
/* Assume the LED is OFF */
return LED_OFF;
}
regval = regval & ~data->mask;
regval = (ror32(data->mask, data->bit) == 0xf0) ? ror32(regval,
data->bit) : ror32(regval, data->bit + 4);
if (regval >= led_data->base_color &&
regval <= (led_data->base_color + MLXREG_LED_OFFSET_BLINK_6HZ))
return LED_FULL;
return LED_OFF;
}
static int
mlxreg_led_brightness_set(struct led_classdev *cled, enum led_brightness value)
{
struct mlxreg_led_data *led_data = cdev_to_priv(cled);
if (value)
return mlxreg_led_store_hw(led_data, led_data->base_color);
else
return mlxreg_led_store_hw(led_data, MLXREG_LED_IS_OFF);
}
static enum led_brightness
mlxreg_led_brightness_get(struct led_classdev *cled)
{
struct mlxreg_led_data *led_data = cdev_to_priv(cled);
return mlxreg_led_get_hw(led_data);
}
static int
mlxreg_led_blink_set(struct led_classdev *cled, unsigned long *delay_on,
unsigned long *delay_off)
{
struct mlxreg_led_data *led_data = cdev_to_priv(cled);
int err;
/*
* HW supports two types of blinking: full (6Hz) and half (3Hz).
* For delay on/off zero LED is setting to solid color. For others
* combination blinking is to be controlled by the software timer.
*/
if (!(*delay_on == 0 && *delay_off == 0) &&
!(*delay_on == MLXREG_LED_BLINK_3HZ &&
*delay_off == MLXREG_LED_BLINK_3HZ) &&
!(*delay_on == MLXREG_LED_BLINK_6HZ &&
*delay_off == MLXREG_LED_BLINK_6HZ))
return -EINVAL;
if (*delay_on == MLXREG_LED_BLINK_6HZ)
err = mlxreg_led_store_hw(led_data, led_data->base_color +
MLXREG_LED_OFFSET_BLINK_6HZ);
else if (*delay_on == MLXREG_LED_BLINK_3HZ)
err = mlxreg_led_store_hw(led_data, led_data->base_color +
MLXREG_LED_OFFSET_BLINK_3HZ);
else
err = mlxreg_led_store_hw(led_data, led_data->base_color);
return err;
}
static int mlxreg_led_config(struct mlxreg_led_priv_data *priv)
{
struct mlxreg_core_platform_data *led_pdata = priv->pdata;
struct mlxreg_core_data *data = led_pdata->data;
struct mlxreg_led_data *led_data;
struct led_classdev *led_cdev;
enum led_brightness brightness;
u32 regval;
int i;
int err;
for (i = 0; i < led_pdata->counter; i++, data++) {
led_data = devm_kzalloc(&priv->pdev->dev, sizeof(*led_data),
GFP_KERNEL);
if (!led_data)
return -ENOMEM;
if (data->capability) {
err = regmap_read(led_pdata->regmap, data->capability,
®val);
if (err) {
dev_err(&priv->pdev->dev, "Failed to query capability register\n");
return err;
}
if (!(regval & data->bit))
continue;
/*
* Field "bit" can contain one capability bit in 0 byte
* and offset bit in 1-3 bytes. Clear capability bit and
* keep only offset bit.
*/
data->bit &= MLXREG_LED_CAPABILITY_CLEAR;
}
led_cdev = &led_data->led_cdev;
led_data->data_parent = priv;
if (strstr(data->label, "red") ||
strstr(data->label, "orange")) {
brightness = LED_OFF;
led_data->base_color = MLXREG_LED_RED_SOLID;
} else if (strstr(data->label, "amber")) {
brightness = LED_OFF;
led_data->base_color = MLXREG_LED_AMBER_SOLID;
} else {
brightness = LED_OFF;
led_data->base_color = MLXREG_LED_GREEN_SOLID;
}
snprintf(led_data->led_cdev_name, sizeof(led_data->led_cdev_name),
"mlxreg:%s", data->label);
led_cdev->name = led_data->led_cdev_name;
led_cdev->brightness = brightness;
led_cdev->max_brightness = LED_ON;
led_cdev->brightness_set_blocking =
mlxreg_led_brightness_set;
led_cdev->brightness_get = mlxreg_led_brightness_get;
led_cdev->blink_set = mlxreg_led_blink_set;
led_cdev->flags = LED_CORE_SUSPENDRESUME;
led_data->data = data;
err = devm_led_classdev_register(&priv->pdev->dev, led_cdev);
if (err)
return err;
if (led_cdev->brightness)
mlxreg_led_brightness_set(led_cdev,
led_cdev->brightness);
dev_info(led_cdev->dev, "label: %s, mask: 0x%02x, offset:0x%02x\n",
data->label, data->mask, data->reg);
}
return 0;
}
static int mlxreg_led_probe(struct platform_device *pdev)
{
struct mlxreg_core_platform_data *led_pdata;
struct mlxreg_led_priv_data *priv;
int err;
led_pdata = dev_get_platdata(&pdev->dev);
if (!led_pdata) {
dev_err(&pdev->dev, "Failed to get platform data.\n");
return -EINVAL;
}
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
err = devm_mutex_init(&pdev->dev, &priv->access_lock);
if (err)
return err;
priv->pdev = pdev;
priv->pdata = led_pdata;
return mlxreg_led_config(priv);
}
static struct platform_driver mlxreg_led_driver = {
.driver = {
.name = "leds-mlxreg",
},
.probe = mlxreg_led_probe,
};
module_platform_driver(mlxreg_led_driver);
MODULE_AUTHOR("Vadim Pasternak <[email protected]>");
MODULE_DESCRIPTION("Mellanox LED regmap driver");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_ALIAS("platform:leds-mlxreg");
Codebase Browser
linux