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-rw-r--r--drivers/leds/leds-pca963x.c442
1 files changed, 442 insertions, 0 deletions
diff --git a/drivers/leds/leds-pca963x.c b/drivers/leds/leds-pca963x.c
new file mode 100644
index 0000000000..47223c850e
--- /dev/null
+++ b/drivers/leds/leds-pca963x.c
@@ -0,0 +1,442 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2011 bct electronic GmbH
+ * Copyright 2013 Qtechnology/AS
+ *
+ * Author: Peter Meerwald <p.meerwald@bct-electronic.com>
+ * Author: Ricardo Ribalda <ribalda@kernel.org>
+ *
+ * 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_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", &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 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,
+ },
+ .probe = pca963x_probe,
+ .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");