--- /dev/null
+/*
+ * 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 PCA9634/5 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/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,
+ pca9635,
+};
+
+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,
+ },
+ [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);
+
+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 .. 15 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", },
+ { .compatible = "nxp,pca9635", },
+ {},
+};
+#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*/
+ for (i = 0; i < chip->n_leds / 4; i++)
+ i2c_smbus_write_byte_data(client, chip->ledout_base + i, 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);
+
+ if (pdata) {
+ /* Configure output: open-drain or totem pole (push-pull) */
+ if (pdata->outdrv == PCA963X_OPEN_DRAIN)
+ i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x01);
+ else
+ i2c_smbus_write_byte_data(client, PCA963X_MODE2, 0x05);
+ }
+
+ 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");
Code Review / kvmfornfv.git / blobdiff