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 000000000000..82589c0a5689
--- /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", &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");