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Diffstat (limited to '')
| -rw-r--r-- | drivers/leds/leds-pca963x.c | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/drivers/leds/leds-pca963x.c b/drivers/leds/leds-pca963x.c new file mode 100644 index 000000000..bbcde13b7 --- /dev/null +++ b/drivers/leds/leds-pca963x.c @@ -0,0 +1,512 @@ +/* + * 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/acpi.h> +#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/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_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); + +static const struct acpi_device_id pca963x_acpi_ids[] = { + { "PCA9632", pca9633 }, + { "PCA9633", pca9633 }, + { "PCA9634", pca9634 }, + { "PCA9635", pca9635 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, pca963x_acpi_ids); + +struct pca963x_led; + +struct pca963x { + struct pca963x_chipdef *chipdef; + struct mutex mutex; + struct i2c_client *client; + struct pca963x_led *leds; + unsigned long leds_on; +}; + +struct pca963x_led { + struct pca963x *chip; + struct led_classdev led_cdev; + int led_num; /* 0 .. 15 potentially */ + char name[32]; + u8 gdc; + u8 gfrq; +}; + +static int pca963x_brightness(struct pca963x_led *pca963x, + enum led_brightness brightness) +{ + 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; + int ret; + + ledout = i2c_smbus_read_byte_data(pca963x->chip->client, ledout_addr); + switch (brightness) { + case LED_FULL: + ret = i2c_smbus_write_byte_data(pca963x->chip->client, + ledout_addr, + (ledout & ~mask) | (PCA963X_LED_ON << shift)); + break; + case LED_OFF: + ret = i2c_smbus_write_byte_data(pca963x->chip->client, + ledout_addr, ledout & ~mask); + break; + default: + ret = i2c_smbus_write_byte_data(pca963x->chip->client, + PCA963X_PWM_BASE + pca963x->led_num, + brightness); + if (ret < 0) + return ret; + ret = i2c_smbus_write_byte_data(pca963x->chip->client, + ledout_addr, + (ledout & ~mask) | (PCA963X_LED_PWM << shift)); + break; + } + + return ret; +} + +static void pca963x_blink(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 int pca963x_power_state(struct pca963x_led *pca963x) +{ + unsigned long *leds_on = &pca963x->chip->leds_on; + unsigned long cached_leds = pca963x->chip->leds_on; + + if (pca963x->led_cdev.brightness) + set_bit(pca963x->led_num, leds_on); + else + clear_bit(pca963x->led_num, leds_on); + + if (!(*leds_on) != !cached_leds) + return i2c_smbus_write_byte_data(pca963x->chip->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 *pca963x; + int ret; + + pca963x = container_of(led_cdev, struct pca963x_led, led_cdev); + + mutex_lock(&pca963x->chip->mutex); + + ret = pca963x_brightness(pca963x, value); + if (ret < 0) + goto unlock; + ret = pca963x_power_state(pca963x); + +unlock: + mutex_unlock(&pca963x->chip->mutex); + return ret; +} + +static unsigned int pca963x_period_scale(struct pca963x_led *pca963x, + unsigned int val) +{ + unsigned int scaling = pca963x->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) +{ + 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 = pca963x_period_scale(pca963x, 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(pca963x, 1000); + } + + /* + * From manual: duty cycle = (GDC / 256) -> + * (time_on / period) = (GDC / 256) -> + * GDC = ((time_on * 256) / period) + */ + gdc = (pca963x_period_scale(pca963x, 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->gdc = gdc; + pca963x->gfrq = gfrq; + + pca963x_blink(pca963x); + + *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_kcalloc(&client->dev, + chip->n_leds, sizeof(struct led_info), 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; + + if (of_property_read_u32(np, "nxp,period-scale", &chip->scaling)) + chip->scaling = 1000; + + /* default to non-inverted output, unless inverted is specified */ + if (of_property_read_bool(np, "nxp,inverted-out")) + pdata->dir = PCA963X_INVERTED; + else + pdata->dir = PCA963X_NORMAL; + + return pdata; +} + +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); +#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; + + if (id) { + chip = &pca963x_chipdefs[id->driver_data]; + } else { + const struct acpi_device_id *acpi_id; + + acpi_id = acpi_match_device(pca963x_acpi_ids, &client->dev); + if (!acpi_id) + return -ENODEV; + chip = &pca963x_chipdefs[acpi_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_kcalloc(&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_blocking = pca963x_led_set; + + if (pdata && pdata->blink_type == PCA963X_HW_BLINK) + pca963x[i].led_cdev.blink_set = pca963x_blink_set; + + err = led_classdev_register(&client->dev, &pca963x[i].led_cdev); + if (err < 0) + goto exit; + } + + /* Disable LED all-call address, and power down initially */ + i2c_smbus_write_byte_data(client, PCA963X_MODE1, BIT(4)); + + if (pdata) { + u8 mode2 = i2c_smbus_read_byte_data(pca963x->chip->client, + PCA963X_MODE2); + /* Configure output: open-drain or totem pole (push-pull) */ + if (pdata->outdrv == PCA963X_OPEN_DRAIN) + mode2 &= ~PCA963X_MODE2_OUTDRV; + else + mode2 |= PCA963X_MODE2_OUTDRV; + /* Configure direction: normal or inverted */ + if (pdata->dir == PCA963X_INVERTED) + mode2 |= PCA963X_MODE2_INVRT; + i2c_smbus_write_byte_data(pca963x->chip->client, PCA963X_MODE2, + mode2); + } + + return 0; + +exit: + while (i--) + led_classdev_unregister(&pca963x[i].led_cdev); + + 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); + + return 0; +} + +static struct i2c_driver pca963x_driver = { + .driver = { + .name = "leds-pca963x", + .of_match_table = of_match_ptr(of_pca963x_match), + .acpi_match_table = ACPI_PTR(pca963x_acpi_ids), + }, + .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"); |