// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright 2011 bct electronic GmbH
* Copyright 2013 Qtechnology/AS
*
* Author: Peter Meerwald <[email protected]>
* Author: Ricardo Ribalda <[email protected]>
*
* Based on leds-pca955x.c
*
* LED driver for the PCA9633 I2C LED driver (7-bit slave address 0x62)
* LED driver for the PCA9634/5 I2C LED driver (7-bit slave address set by hw.)
*
* Note that hardware blinking violates the leds infrastructure driver
* interface since the hardware only supports blinking all LEDs with the
* same delay_on/delay_off rates. That is, only the LEDs that are set to
* blink will actually blink but all LEDs that are set to blink will blink
* in identical fashion. The delay_on/delay_off values of the last LED
* that is set to blink will be used for all of the blinking LEDs.
* Hardware blinking is disabled by default but can be enabled by setting
* the 'blink_type' member in the platform_data struct to 'PCA963X_HW_BLINK'
* or by adding the 'nxp,hw-blink' property to the DTS.
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/leds.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/property.h>
#include <linux/slab.h>
#include <linux/of.h>
/* LED select registers determine the source that drives LED outputs */
#define PCA963X_LED_OFF 0x0 /* LED driver off */
#define PCA963X_LED_ON 0x1 /* LED driver on */
#define PCA963X_LED_PWM 0x2 /* Controlled through PWM */
#define PCA963X_LED_GRP_PWM 0x3 /* Controlled through PWM/GRPPWM */
#define PCA963X_MODE1_SLEEP 0x04 /* Normal mode or Low Power mode, oscillator off */
#define PCA963X_MODE2_OUTDRV 0x04 /* Open-drain or totem pole */
#define PCA963X_MODE2_INVRT 0x10 /* Normal or inverted direction */
#define PCA963X_MODE2_DMBLNK 0x20 /* Enable blinking */
#define PCA963X_MODE1 0x00
#define PCA963X_MODE2 0x01
#define PCA963X_PWM_BASE 0x02
enum pca963x_type {
pca9633,
pca9634,
pca9635,
};
struct pca963x_chipdef {
u8 grppwm;
u8 grpfreq;
u8 ledout_base;
int n_leds;
unsigned int scaling;
};
static struct pca963x_chipdef pca963x_chipdefs[] = {
[pca9633] = {
.grppwm = 0x6,
.grpfreq = 0x7,
.ledout_base = 0x8,
.n_leds = 4,
},
[pca9634] = {
.grppwm = 0xa,
.grpfreq = 0xb,
.ledout_base = 0xc,
.n_leds = 8,
},
[pca9635] = {
.grppwm = 0x12,
.grpfreq = 0x13,
.ledout_base = 0x14,
.n_leds = 16,
},
};
/* Total blink period in milliseconds */
#define PCA963X_BLINK_PERIOD_MIN 42
#define PCA963X_BLINK_PERIOD_MAX 10667
static const struct i2c_device_id pca963x_id[] = {
{ "pca9632", pca9633 },
{ "pca9633", pca9633 },
{ "pca9634", pca9634 },
{ "pca9635", pca9635 },
{ }
};
MODULE_DEVICE_TABLE(i2c, pca963x_id);
struct pca963x;
struct pca963x_led {
struct pca963x *chip;
struct led_classdev led_cdev;
int led_num; /* 0 .. 15 potentially */
bool blinking;
u8 gdc;
u8 gfrq;
};
struct pca963x {
struct pca963x_chipdef *chipdef;
struct mutex mutex;
struct i2c_client *client;
unsigned long leds_on;
struct pca963x_led leds[];
};
static int pca963x_brightness(struct pca963x_led *led,
enum led_brightness brightness)
{
struct i2c_client *client = led->chip->client;
struct pca963x_chipdef *chipdef = led->chip->chipdef;
u8 ledout_addr, ledout, mask, val;
int shift;
int ret;
ledout_addr = chipdef->ledout_base + (led->led_num / 4);
shift = 2 * (led->led_num % 4);
mask = 0x3 << shift;
ledout = i2c_smbus_read_byte_data(client, ledout_addr);
switch (brightness) {
case LED_FULL:
if (led->blinking) {
val = (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift);
ret = i2c_smbus_write_byte_data(client,
PCA963X_PWM_BASE +
led->led_num,
LED_FULL);
} else {
val = (ledout & ~mask) | (PCA963X_LED_ON << shift);
}
ret = i2c_smbus_write_byte_data(client, ledout_addr, val);
break;
case LED_OFF:
val = ledout & ~mask;
ret = i2c_smbus_write_byte_data(client, ledout_addr, val);
led->blinking = false;
break;
default:
ret = i2c_smbus_write_byte_data(client,
PCA963X_PWM_BASE +
led->led_num,
brightness);
if (ret < 0)
return ret;
if (led->blinking)
val = (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift);
else
val = (ledout & ~mask) | (PCA963X_LED_PWM << shift);
ret = i2c_smbus_write_byte_data(client, ledout_addr, val);
break;
}
return ret;
}
static void pca963x_blink(struct pca963x_led *led)
{
struct i2c_client *client = led->chip->client;
struct pca963x_chipdef *chipdef = led->chip->chipdef;
u8 ledout_addr, ledout, mask, val, mode2;
int shift;
ledout_addr = chipdef->ledout_base + (led->led_num / 4);
shift = 2 * (led->led_num % 4);
mask = 0x3 << shift;
mode2 = i2c_smbus_read_byte_data(client, PCA963X_MODE2);
i2c_smbus_write_byte_data(client, chipdef->grppwm, led->gdc);
i2c_smbus_write_byte_data(client, chipdef->grpfreq, led->gfrq);
if (!(mode2 & PCA963X_MODE2_DMBLNK))
i2c_smbus_write_byte_data(client, PCA963X_MODE2,
mode2 | PCA963X_MODE2_DMBLNK);
mutex_lock(&led->chip->mutex);
ledout = i2c_smbus_read_byte_data(client, ledout_addr);
if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift)) {
val = (ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift);
i2c_smbus_write_byte_data(client, ledout_addr, val);
}
mutex_unlock(&led->chip->mutex);
led->blinking = true;
}
static int pca963x_power_state(struct pca963x_led *led)
{
struct i2c_client *client = led->chip->client;
unsigned long *leds_on = &led->chip->leds_on;
unsigned long cached_leds = *leds_on;
if (led->led_cdev.brightness)
set_bit(led->led_num, leds_on);
else
clear_bit(led->led_num, leds_on);
if (!(*leds_on) != !cached_leds)
return i2c_smbus_write_byte_data(client, PCA963X_MODE1,
*leds_on ? 0 : BIT(4));
return 0;
}
static int pca963x_led_set(struct led_classdev *led_cdev,
enum led_brightness value)
{
struct pca963x_led *led;
int ret;
led = container_of(led_cdev, struct pca963x_led, led_cdev);
mutex_lock(&led->chip->mutex);
ret = pca963x_brightness(led, value);
if (ret < 0)
goto unlock;
ret = pca963x_power_state(led);
unlock:
mutex_unlock(&led->chip->mutex);
return ret;
}
static unsigned int pca963x_period_scale(struct pca963x_led *led,
unsigned int val)
{
unsigned int scaling = led->chip->chipdef->scaling;
return scaling ? DIV_ROUND_CLOSEST(val * scaling, 1000) : val;
}
static int pca963x_blink_set(struct led_classdev *led_cdev,
unsigned long *delay_on, unsigned long *delay_off)
{
unsigned long time_on, time_off, period;
struct pca963x_led *led;
u8 gdc, gfrq;
led = container_of(led_cdev, struct pca963x_led, led_cdev);
time_on = *delay_on;
time_off = *delay_off;
/* If both zero, pick reasonable defaults of 500ms each */
if (!time_on && !time_off) {
time_on = 500;
time_off = 500;
}
period = pca963x_period_scale(led, time_on + time_off);
/* If period not supported by hardware, default to someting sane. */
if ((period < PCA963X_BLINK_PERIOD_MIN) ||
(period > PCA963X_BLINK_PERIOD_MAX)) {
time_on = 500;
time_off = 500;
period = pca963x_period_scale(led, 1000);
}
/*
* From manual: duty cycle = (GDC / 256) ->
* (time_on / period) = (GDC / 256) ->
* GDC = ((time_on * 256) / period)
*/
gdc = (pca963x_period_scale(led, time_on) * 256) / period;
/*
* From manual: period = ((GFRQ + 1) / 24) in seconds.
* So, period (in ms) = (((GFRQ + 1) / 24) * 1000) ->
* GFRQ = ((period * 24 / 1000) - 1)
*/
gfrq = (period * 24 / 1000) - 1;
led->gdc = gdc;
led->gfrq = gfrq;
pca963x_blink(led);
led->led_cdev.brightness = LED_FULL;
pca963x_led_set(led_cdev, LED_FULL);
*delay_on = time_on;
*delay_off = time_off;
return 0;
}
static int pca963x_register_leds(struct i2c_client *client,
struct pca963x *chip)
{
struct pca963x_chipdef *chipdef = chip->chipdef;
struct pca963x_led *led = chip->leds;
struct device *dev = &client->dev;
struct fwnode_handle *child;
bool hw_blink;
s32 mode2;
u32 reg;
int ret;
if (device_property_read_u32(dev, "nxp,period-scale",
&chipdef->scaling))
chipdef->scaling = 1000;
hw_blink = device_property_read_bool(dev, "nxp,hw-blink");
mode2 = i2c_smbus_read_byte_data(client, PCA963X_MODE2);
if (mode2 < 0)
return mode2;
/* default to open-drain unless totem pole (push-pull) is specified */
if (device_property_read_bool(dev, "nxp,totem-pole"))
mode2 |= PCA963X_MODE2_OUTDRV;
else
mode2 &= ~PCA963X_MODE2_OUTDRV;
/* default to non-inverted output, unless inverted is specified */
if (device_property_read_bool(dev, "nxp,inverted-out"))
mode2 |= PCA963X_MODE2_INVRT;
else
mode2 &= ~PCA963X_MODE2_INVRT;
ret = i2c_smbus_write_byte_data(client, PCA963X_MODE2, mode2);
if (ret < 0)
return ret;
device_for_each_child_node(dev, child) {
struct led_init_data init_data = {};
char default_label[32];
ret = fwnode_property_read_u32(child, "reg", ®);
if (ret || reg >= chipdef->n_leds) {
dev_err(dev, "Invalid 'reg' property for node %pfw\n",
child);
ret = -EINVAL;
goto err;
}
led->led_num = reg;
led->chip = chip;
led->led_cdev.brightness_set_blocking = pca963x_led_set;
if (hw_blink)
led->led_cdev.blink_set = pca963x_blink_set;
led->blinking = false;
init_data.fwnode = child;
/* for backwards compatibility */
init_data.devicename = "pca963x";
snprintf(default_label, sizeof(default_label), "%d:%.2x:%u",
client->adapter->nr, client->addr, reg);
init_data.default_label = default_label;
ret = devm_led_classdev_register_ext(dev, &led->led_cdev,
&init_data);
if (ret) {
dev_err(dev, "Failed to register LED for node %pfw\n",
child);
goto err;
}
++led;
}
return 0;
err:
fwnode_handle_put(child);
return ret;
}
static int pca963x_suspend(struct device *dev)
{
struct pca963x *chip = dev_get_drvdata(dev);
u8 reg;
reg = i2c_smbus_read_byte_data(chip->client, PCA963X_MODE1);
reg = reg | BIT(PCA963X_MODE1_SLEEP);
i2c_smbus_write_byte_data(chip->client, PCA963X_MODE1, reg);
return 0;
}
static int pca963x_resume(struct device *dev)
{
struct pca963x *chip = dev_get_drvdata(dev);
u8 reg;
reg = i2c_smbus_read_byte_data(chip->client, PCA963X_MODE1);
reg = reg & ~BIT(PCA963X_MODE1_SLEEP);
i2c_smbus_write_byte_data(chip->client, PCA963X_MODE1, reg);
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(pca963x_pm, pca963x_suspend, pca963x_resume);
static const struct of_device_id of_pca963x_match[] = {
{ .compatible = "nxp,pca9632", },
{ .compatible = "nxp,pca9633", },
{ .compatible = "nxp,pca9634", },
{ .compatible = "nxp,pca9635", },
{},
};
MODULE_DEVICE_TABLE(of, of_pca963x_match);
static int pca963x_probe(struct i2c_client *client)
{
const struct i2c_device_id *id = i2c_client_get_device_id(client);
struct device *dev = &client->dev;
struct pca963x_chipdef *chipdef;
struct pca963x *chip;
int i, count;
chipdef = &pca963x_chipdefs[id->driver_data];
count = device_get_child_node_count(dev);
if (!count || count > chipdef->n_leds) {
dev_err(dev, "Node %pfw must define between 1 and %d LEDs\n",
dev_fwnode(dev), chipdef->n_leds);
return -EINVAL;
}
chip = devm_kzalloc(dev, struct_size(chip, leds, count), GFP_KERNEL);
if (!chip)
return -ENOMEM;
i2c_set_clientdata(client, chip);
mutex_init(&chip->mutex);
chip->chipdef = chipdef;
chip->client = client;
/* Turn off LEDs by default*/
for (i = 0; i < chipdef->n_leds / 4; i++)
i2c_smbus_write_byte_data(client, chipdef->ledout_base + i, 0x00);
/* Disable LED all-call address, and power down initially */
i2c_smbus_write_byte_data(client, PCA963X_MODE1, BIT(4));
return pca963x_register_leds(client, chip);
}
static struct i2c_driver pca963x_driver = {
.driver = {
.name = "leds-pca963x",
.of_match_table = of_pca963x_match,
.pm = pm_sleep_ptr(&pca963x_pm)
},
.probe = pca963x_probe,
.id_table = pca963x_id,
};
module_i2c_driver(pca963x_driver);
MODULE_AUTHOR("Peter Meerwald <[email protected]>");
MODULE_DESCRIPTION("PCA963X LED driver");
MODULE_LICENSE("GPL v2");
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