diff options
Diffstat (limited to 'drivers/leds/leds-pca963x.c')
| -rw-r--r-- | drivers/leds/leds-pca963x.c | 461 | 
1 files changed, 461 insertions, 0 deletions
diff --git a/drivers/leds/leds-pca963x.c b/drivers/leds/leds-pca963x.c new file mode 100644 index 00000000000..82589c0a568 --- /dev/null +++ b/drivers/leds/leds-pca963x.c @@ -0,0 +1,461 @@ +/* + * Copyright 2011 bct electronic GmbH + * Copyright 2013 Qtechnology/AS + * + * Author: Peter Meerwald <p.meerwald@bct-electronic.com> + * Author: Ricardo Ribalda <ricardo.ribalda@gmail.com> + * + * Based on leds-pca955x.c + * + * This file is subject to the terms and conditions of version 2 of + * the GNU General Public License.  See the file COPYING in the main + * directory of this archive for more details. + * + * LED driver for the PCA9633 I2C LED driver (7-bit slave address 0x62) + * LED driver for the PCA9634 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/workqueue.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/platform_data/leds-pca963x.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_MODE2_DMBLNK	0x20	/* Enable blinking */ + +#define PCA963X_MODE1		0x00 +#define PCA963X_MODE2		0x01 +#define PCA963X_PWM_BASE	0x02 + +enum pca963x_type { +	pca9633, +	pca9634, +}; + +struct pca963x_chipdef { +	u8			grppwm; +	u8			grpfreq; +	u8			ledout_base; +	int			n_leds; +}; + +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, +	}, +}; + +/* 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 }, +	{ } +}; +MODULE_DEVICE_TABLE(i2c, pca963x_id); + +enum pca963x_cmd { +	BRIGHTNESS_SET, +	BLINK_SET, +}; + +struct pca963x_led; + +struct pca963x { +	struct pca963x_chipdef *chipdef; +	struct mutex mutex; +	struct i2c_client *client; +	struct pca963x_led *leds; +}; + +struct pca963x_led { +	struct pca963x *chip; +	struct work_struct work; +	enum led_brightness brightness; +	struct led_classdev led_cdev; +	int led_num; /* 0 .. 7 potentially */ +	enum pca963x_cmd cmd; +	char name[32]; +	u8 gdc; +	u8 gfrq; +}; + +static void pca963x_brightness_work(struct pca963x_led *pca963x) +{ +	u8 ledout_addr = pca963x->chip->chipdef->ledout_base +		+ (pca963x->led_num / 4); +	u8 ledout; +	int shift = 2 * (pca963x->led_num % 4); +	u8 mask = 0x3 << shift; + +	mutex_lock(&pca963x->chip->mutex); +	ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); +	switch (pca963x->brightness) { +	case LED_FULL: +		i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, +			(ledout & ~mask) | (PCA963X_LED_ON << shift)); +		break; +	case LED_OFF: +		i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, +			ledout & ~mask); +		break; +	default: +		i2c_smbus_write_byte_data(pca963x->chip->client, +			PCA963X_PWM_BASE + pca963x->led_num, +			pca963x->brightness); +		i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, +			(ledout & ~mask) | (PCA963X_LED_PWM << shift)); +		break; +	} +	mutex_unlock(&pca963x->chip->mutex); +} + +static void pca963x_blink_work(struct pca963x_led *pca963x) +{ +	u8 ledout_addr = pca963x->chip->chipdef->ledout_base + +		(pca963x->led_num / 4); +	u8 ledout; +	u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client, +							PCA963X_MODE2); +	int shift = 2 * (pca963x->led_num % 4); +	u8 mask = 0x3 << shift; + +	i2c_smbus_write_byte_data(pca963x->chip->client, +			pca963x->chip->chipdef->grppwm,	pca963x->gdc); + +	i2c_smbus_write_byte_data(pca963x->chip->client, +			pca963x->chip->chipdef->grpfreq, pca963x->gfrq); + +	if (!(mode2 & PCA963X_MODE2_DMBLNK)) +		i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2, +			mode2 | PCA963X_MODE2_DMBLNK); + +	mutex_lock(&pca963x->chip->mutex); +	ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); +	if ((ledout & mask) != (PCA963X_LED_GRP_PWM << shift)) +		i2c_smbus_write_byte_data(pca963x->chip->client, ledout_addr, +			(ledout & ~mask) | (PCA963X_LED_GRP_PWM << shift)); +	mutex_unlock(&pca963x->chip->mutex); +} + +static void pca963x_work(struct work_struct *work) +{ +	struct pca963x_led *pca963x = container_of(work, +		struct pca963x_led, work); + +	switch (pca963x->cmd) { +	case BRIGHTNESS_SET: +		pca963x_brightness_work(pca963x); +		break; +	case BLINK_SET: +		pca963x_blink_work(pca963x); +		break; +	} +} + +static void pca963x_led_set(struct led_classdev *led_cdev, +	enum led_brightness value) +{ +	struct pca963x_led *pca963x; + +	pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); + +	pca963x->cmd = BRIGHTNESS_SET; +	pca963x->brightness = value; + +	/* +	 * Must use workqueue for the actual I/O since I2C operations +	 * can sleep. +	 */ +	schedule_work(&pca963x->work); +} + +static int pca963x_blink_set(struct led_classdev *led_cdev, +		unsigned long *delay_on, unsigned long *delay_off) +{ +	struct pca963x_led *pca963x; +	unsigned long time_on, time_off, period; +	u8 gdc, gfrq; + +	pca963x = 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 = 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 = time_on + time_off; +	} + +	/* +	 * From manual: duty cycle = (GDC / 256) -> +	 *	(time_on / period) = (GDC / 256) -> +	 *		GDC = ((time_on * 256) / period) +	 */ +	gdc = (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; + +	pca963x->cmd = BLINK_SET; +	pca963x->gdc = gdc; +	pca963x->gfrq = gfrq; + +	/* +	 * Must use workqueue for the actual I/O since I2C operations +	 * can sleep. +	 */ +	schedule_work(&pca963x->work); + +	*delay_on = time_on; +	*delay_off = time_off; + +	return 0; +} + +#if IS_ENABLED(CONFIG_OF) +static struct pca963x_platform_data * +pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) +{ +	struct device_node *np = client->dev.of_node, *child; +	struct pca963x_platform_data *pdata; +	struct led_info *pca963x_leds; +	int count; + +	count = of_get_child_count(np); +	if (!count || count > chip->n_leds) +		return ERR_PTR(-ENODEV); + +	pca963x_leds = devm_kzalloc(&client->dev, +			sizeof(struct led_info) * chip->n_leds, GFP_KERNEL); +	if (!pca963x_leds) +		return ERR_PTR(-ENOMEM); + +	for_each_child_of_node(np, child) { +		struct led_info led; +		u32 reg; +		int res; + +		res = of_property_read_u32(child, "reg", ®); +		if ((res != 0) || (reg >= chip->n_leds)) +			continue; +		led.name = +			of_get_property(child, "label", NULL) ? : child->name; +		led.default_trigger = +			of_get_property(child, "linux,default-trigger", NULL); +		pca963x_leds[reg] = led; +	} +	pdata = devm_kzalloc(&client->dev, +			     sizeof(struct pca963x_platform_data), GFP_KERNEL); +	if (!pdata) +		return ERR_PTR(-ENOMEM); + +	pdata->leds.leds = pca963x_leds; +	pdata->leds.num_leds = chip->n_leds; + +	/* default to open-drain unless totem pole (push-pull) is specified */ +	if (of_property_read_bool(np, "nxp,totem-pole")) +		pdata->outdrv = PCA963X_TOTEM_POLE; +	else +		pdata->outdrv = PCA963X_OPEN_DRAIN; + +	/* default to software blinking unless hardware blinking is specified */ +	if (of_property_read_bool(np, "nxp,hw-blink")) +		pdata->blink_type = PCA963X_HW_BLINK; +	else +		pdata->blink_type = PCA963X_SW_BLINK; + +	return pdata; +} + +static const struct of_device_id of_pca963x_match[] = { +	{ .compatible = "nxp,pca9632", }, +	{ .compatible = "nxp,pca9633", }, +	{ .compatible = "nxp,pca9634", }, +	{}, +}; +#else +static struct pca963x_platform_data * +pca963x_dt_init(struct i2c_client *client, struct pca963x_chipdef *chip) +{ +	return ERR_PTR(-ENODEV); +} +#endif + +static int pca963x_probe(struct i2c_client *client, +					const struct i2c_device_id *id) +{ +	struct pca963x *pca963x_chip; +	struct pca963x_led *pca963x; +	struct pca963x_platform_data *pdata; +	struct pca963x_chipdef *chip; +	int i, err; + +	chip = &pca963x_chipdefs[id->driver_data]; +	pdata = dev_get_platdata(&client->dev); + +	if (!pdata) { +		pdata = pca963x_dt_init(client, chip); +		if (IS_ERR(pdata)) { +			dev_warn(&client->dev, "could not parse configuration\n"); +			pdata = NULL; +		} +	} + +	if (pdata && (pdata->leds.num_leds < 1 || +				 pdata->leds.num_leds > chip->n_leds)) { +		dev_err(&client->dev, "board info must claim 1-%d LEDs", +								chip->n_leds); +		return -EINVAL; +	} + +	pca963x_chip = devm_kzalloc(&client->dev, sizeof(*pca963x_chip), +								GFP_KERNEL); +	if (!pca963x_chip) +		return -ENOMEM; +	pca963x = devm_kzalloc(&client->dev, chip->n_leds * sizeof(*pca963x), +								GFP_KERNEL); +	if (!pca963x) +		return -ENOMEM; + +	i2c_set_clientdata(client, pca963x_chip); + +	mutex_init(&pca963x_chip->mutex); +	pca963x_chip->chipdef = chip; +	pca963x_chip->client = client; +	pca963x_chip->leds = pca963x; + +	/* Turn off LEDs by default*/ +	i2c_smbus_write_byte_data(client, chip->ledout_base, 0x00); +	if (chip->n_leds > 4) +		i2c_smbus_write_byte_data(client, chip->ledout_base + 1, 0x00); + +	for (i = 0; i < chip->n_leds; i++) { +		pca963x[i].led_num = i; +		pca963x[i].chip = pca963x_chip; + +		/* Platform data can specify LED names and default triggers */ +		if (pdata && i < pdata->leds.num_leds) { +			if (pdata->leds.leds[i].name) +				snprintf(pca963x[i].name, +					 sizeof(pca963x[i].name), "pca963x:%s", +					 pdata->leds.leds[i].name); +			if (pdata->leds.leds[i].default_trigger) +				pca963x[i].led_cdev.default_trigger = +					pdata->leds.leds[i].default_trigger; +		} +		if (!pdata || i >= pdata->leds.num_leds || +						!pdata->leds.leds[i].name) +			snprintf(pca963x[i].name, sizeof(pca963x[i].name), +				 "pca963x:%d:%.2x:%d", client->adapter->nr, +				 client->addr, i); + +		pca963x[i].led_cdev.name = pca963x[i].name; +		pca963x[i].led_cdev.brightness_set = pca963x_led_set; + +		if (pdata && pdata->blink_type == PCA963X_HW_BLINK) +			pca963x[i].led_cdev.blink_set = pca963x_blink_set; + +		INIT_WORK(&pca963x[i].work, pca963x_work); + +		err = led_classdev_register(&client->dev, &pca963x[i].led_cdev); +		if (err < 0) +			goto exit; +	} + +	/* Disable LED all-call address and set normal mode */ +	i2c_smbus_write_byte_data(client, PCA963X_MODE1, 0x00); + +	/* Configure output: open-drain or totem pole (push-pull) */ +	if (pdata && pdata->outdrv == PCA963X_OPEN_DRAIN) +		i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x01); + +	return 0; + +exit: +	while (i--) { +		led_classdev_unregister(&pca963x[i].led_cdev); +		cancel_work_sync(&pca963x[i].work); +	} + +	return err; +} + +static int pca963x_remove(struct i2c_client *client) +{ +	struct pca963x *pca963x = i2c_get_clientdata(client); +	int i; + +	for (i = 0; i < pca963x->chipdef->n_leds; i++) { +		led_classdev_unregister(&pca963x->leds[i].led_cdev); +		cancel_work_sync(&pca963x->leds[i].work); +	} + +	return 0; +} + +static struct i2c_driver pca963x_driver = { +	.driver = { +		.name	= "leds-pca963x", +		.owner	= THIS_MODULE, +		.of_match_table = of_match_ptr(of_pca963x_match), +	}, +	.probe	= pca963x_probe, +	.remove	= pca963x_remove, +	.id_table = pca963x_id, +}; + +module_i2c_driver(pca963x_driver); + +MODULE_AUTHOR("Peter Meerwald <p.meerwald@bct-electronic.com>"); +MODULE_DESCRIPTION("PCA963X LED driver"); +MODULE_LICENSE("GPL v2");  | 
