diff options
| -rw-r--r-- | drivers/leds/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/leds/Makefile | 1 | ||||
| -rw-r--r-- | drivers/leds/leds-is31fl319x.c | 450 |
3 files changed, 463 insertions, 0 deletions
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 9dcc9b13d495..6df9a2f098f5 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -584,6 +584,18 @@ config LEDS_SEAD3 This driver can also be built as a module. If so the module will be called leds-sead3. +config LEDS_IS31FL319X + tristate "LED Support for ISSI IS31FL319x I2C LED controller family" + depends on LEDS_CLASS && I2C && OF + select REGMAP_I2C + help + This option enables support for LEDs connected to ISSI IS31FL319x + fancy LED driver chips accessed via the I2C bus. + Driver supports individual PWM brightness control for each channel. + + This driver can also be built as a module. If so the module will be + called leds-is31fl319x. + config LEDS_IS31FL32XX tristate "LED support for ISSI IS31FL32XX I2C LED controller family" depends on LEDS_CLASS && I2C && OF diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 0684c865a1c0..e7a0e4edadd4 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -67,6 +67,7 @@ obj-$(CONFIG_LEDS_MENF21BMC) += leds-menf21bmc.o obj-$(CONFIG_LEDS_KTD2692) += leds-ktd2692.o obj-$(CONFIG_LEDS_POWERNV) += leds-powernv.o obj-$(CONFIG_LEDS_SEAD3) += leds-sead3.o +obj-$(CONFIG_LEDS_IS31FL319X) += leds-is31fl319x.o obj-$(CONFIG_LEDS_IS31FL32XX) += leds-is31fl32xx.o # LED SPI Drivers diff --git a/drivers/leds/leds-is31fl319x.c b/drivers/leds/leds-is31fl319x.c new file mode 100644 index 000000000000..f123309597e4 --- /dev/null +++ b/drivers/leds/leds-is31fl319x.c @@ -0,0 +1,450 @@ +/* + * Copyright 2015-16 Golden Delicious Computers + * + * Author: Nikolaus Schaller <hns@goldelico.com> + * + * 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 IS31FL319{0,1,3,6,9} to drive 1, 3, 6 or 9 light + * effect LEDs. + * + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +/* register numbers */ +#define IS31FL319X_SHUTDOWN 0x00 +#define IS31FL319X_CTRL1 0x01 +#define IS31FL319X_CTRL2 0x02 +#define IS31FL319X_CONFIG1 0x03 +#define IS31FL319X_CONFIG2 0x04 +#define IS31FL319X_RAMP_MODE 0x05 +#define IS31FL319X_BREATH_MASK 0x06 +#define IS31FL319X_PWM(channel) (0x07 + channel) +#define IS31FL319X_DATA_UPDATE 0x10 +#define IS31FL319X_T0(channel) (0x11 + channel) +#define IS31FL319X_T123_1 0x1a +#define IS31FL319X_T123_2 0x1b +#define IS31FL319X_T123_3 0x1c +#define IS31FL319X_T4(channel) (0x1d + channel) +#define IS31FL319X_TIME_UPDATE 0x26 +#define IS31FL319X_RESET 0xff + +#define IS31FL319X_REG_CNT (IS31FL319X_RESET + 1) + +#define IS31FL319X_MAX_LEDS 9 + +/* CS (Current Setting) in CONFIG2 register */ +#define IS31FL319X_CONFIG2_CS_SHIFT 4 +#define IS31FL319X_CONFIG2_CS_MASK 0x7 +#define IS31FL319X_CONFIG2_CS_STEP_REF 12 + +#define IS31FL319X_CURRENT_MIN ((u32)5000) +#define IS31FL319X_CURRENT_MAX ((u32)40000) +#define IS31FL319X_CURRENT_STEP ((u32)5000) +#define IS31FL319X_CURRENT_DEFAULT ((u32)20000) + +/* Audio gain in CONFIG2 register */ +#define IS31FL319X_AUDIO_GAIN_DB_MAX ((u32)21) +#define IS31FL319X_AUDIO_GAIN_DB_STEP ((u32)3) + +/* + * regmap is used as a cache of chip's register space, + * to avoid reading back brightness values from chip, + * which is known to hang. + */ +struct is31fl319x_chip { + const struct is31fl319x_chipdef *cdef; + struct i2c_client *client; + struct regmap *regmap; + struct mutex lock; + u32 audio_gain_db; + + struct is31fl319x_led { + struct is31fl319x_chip *chip; + struct led_classdev cdev; + u32 max_microamp; + bool configured; + } leds[IS31FL319X_MAX_LEDS]; +}; + +struct is31fl319x_chipdef { + int num_leds; +}; + +static const struct is31fl319x_chipdef is31fl3190_cdef = { + .num_leds = 1, +}; + +static const struct is31fl319x_chipdef is31fl3193_cdef = { + .num_leds = 3, +}; + +static const struct is31fl319x_chipdef is31fl3196_cdef = { + .num_leds = 6, +}; + +static const struct is31fl319x_chipdef is31fl3199_cdef = { + .num_leds = 9, +}; + +static const struct of_device_id of_is31fl319x_match[] = { + { .compatible = "issi,is31fl3190", .data = &is31fl3190_cdef, }, + { .compatible = "issi,is31fl3191", .data = &is31fl3190_cdef, }, + { .compatible = "issi,is31fl3193", .data = &is31fl3193_cdef, }, + { .compatible = "issi,is31fl3196", .data = &is31fl3196_cdef, }, + { .compatible = "issi,is31fl3199", .data = &is31fl3199_cdef, }, + { .compatible = "si-en,sn3199", .data = &is31fl3199_cdef, }, + { } +}; +MODULE_DEVICE_TABLE(of, of_is31fl319x_match); + +static int is31fl319x_brightness_set(struct led_classdev *cdev, + enum led_brightness brightness) +{ + struct is31fl319x_led *led = container_of(cdev, struct is31fl319x_led, + cdev); + struct is31fl319x_chip *is31 = led->chip; + int chan = led - is31->leds; + int ret; + int i; + u8 ctrl1 = 0, ctrl2 = 0; + + dev_dbg(&is31->client->dev, "%s %d: %d\n", __func__, chan, brightness); + + mutex_lock(&is31->lock); + + /* update PWM register */ + ret = regmap_write(is31->regmap, IS31FL319X_PWM(chan), brightness); + if (ret < 0) + goto out; + + /* read current brightness of all PWM channels */ + for (i = 0; i < is31->cdef->num_leds; i++) { + unsigned int pwm_value; + bool on; + + /* + * since neither cdev nor the chip can provide + * the current setting, we read from the regmap cache + */ + + ret = regmap_read(is31->regmap, IS31FL319X_PWM(i), &pwm_value); + dev_dbg(&is31->client->dev, "%s read %d: ret=%d: %d\n", + __func__, i, ret, pwm_value); + on = ret >= 0 && pwm_value > LED_OFF; + + if (i < 3) + ctrl1 |= on << i; /* 0..2 => bit 0..2 */ + else if (i < 6) + ctrl1 |= on << (i + 1); /* 3..5 => bit 4..6 */ + else + ctrl2 |= on << (i - 6); /* 6..8 => bit 0..2 */ + } + + if (ctrl1 > 0 || ctrl2 > 0) { + dev_dbg(&is31->client->dev, "power up %02x %02x\n", + ctrl1, ctrl2); + regmap_write(is31->regmap, IS31FL319X_CTRL1, ctrl1); + regmap_write(is31->regmap, IS31FL319X_CTRL2, ctrl2); + /* update PWMs */ + regmap_write(is31->regmap, IS31FL319X_DATA_UPDATE, 0x00); + /* enable chip from shut down */ + ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x01); + } else { + dev_dbg(&is31->client->dev, "power down\n"); + /* shut down (no need to clear CTRL1/2) */ + ret = regmap_write(is31->regmap, IS31FL319X_SHUTDOWN, 0x00); + } + +out: + mutex_unlock(&is31->lock); + + return ret; +} + +static int is31fl319x_parse_child_dt(const struct device *dev, + const struct device_node *child, + struct is31fl319x_led *led) +{ + struct led_classdev *cdev = &led->cdev; + int ret; + + if (of_property_read_string(child, "label", &cdev->name)) + cdev->name = child->name; + + ret = of_property_read_string(child, "linux,default-trigger", + &cdev->default_trigger); + if (ret < 0 && ret != -EINVAL) /* is optional */ + return ret; + + led->max_microamp = IS31FL319X_CURRENT_DEFAULT; + ret = of_property_read_u32(child, "led-max-microamp", + &led->max_microamp); + if (!ret) { + if (led->max_microamp < IS31FL319X_CURRENT_MIN) + return -EINVAL; /* not supported */ + led->max_microamp = min(led->max_microamp, + IS31FL319X_CURRENT_MAX); + } + + return 0; +} + +static int is31fl319x_parse_dt(struct device *dev, + struct is31fl319x_chip *is31) +{ + struct device_node *np = dev->of_node, *child; + const struct of_device_id *of_dev_id; + int count; + int ret; + + if (!np) + return -ENODEV; + + of_dev_id = of_match_device(of_is31fl319x_match, dev); + if (!of_dev_id) { + dev_err(dev, "Failed to match device with supported chips\n"); + return -EINVAL; + } + + is31->cdef = of_dev_id->data; + + count = of_get_child_count(np); + + dev_dbg(dev, "probe %s with %d leds defined in DT\n", + of_dev_id->compatible, count); + + if (!count || count > is31->cdef->num_leds) { + dev_err(dev, "Number of leds defined must be between 1 and %u\n", + is31->cdef->num_leds); + return -ENODEV; + } + + for_each_child_of_node(np, child) { + struct is31fl319x_led *led; + u32 reg; + + ret = of_property_read_u32(child, "reg", ®); + if (ret) { + dev_err(dev, "Failed to read led 'reg' property\n"); + goto put_child_node; + } + + if (reg < 1 || reg > is31->cdef->num_leds) { + dev_err(dev, "invalid led reg %u\n", reg); + ret = -EINVAL; + goto put_child_node; + } + + led = &is31->leds[reg - 1]; + + if (led->configured) { + dev_err(dev, "led %u is already configured\n", reg); + ret = -EINVAL; + goto put_child_node; + } + + ret = is31fl319x_parse_child_dt(dev, child, led); + if (ret) { + dev_err(dev, "led %u DT parsing failed\n", reg); + goto put_child_node; + } + + led->configured = true; + } + + is31->audio_gain_db = 0; + ret = of_property_read_u32(np, "audio-gain-db", &is31->audio_gain_db); + if (!ret) + is31->audio_gain_db = min(is31->audio_gain_db, + IS31FL319X_AUDIO_GAIN_DB_MAX); + + return 0; + +put_child_node: + of_node_put(child); + return ret; +} + +static bool is31fl319x_readable_reg(struct device *dev, unsigned int reg) +{ /* we have no readable registers */ + return false; +} + +static bool is31fl319x_volatile_reg(struct device *dev, unsigned int reg) +{ /* volatile registers are not cached */ + switch (reg) { + case IS31FL319X_DATA_UPDATE: + case IS31FL319X_TIME_UPDATE: + case IS31FL319X_RESET: + return true; /* always write-through */ + default: + return false; + } +} + +static const struct reg_default is31fl319x_reg_defaults[] = { + { IS31FL319X_CONFIG1, 0x00}, + { IS31FL319X_CONFIG2, 0x00}, + { IS31FL319X_PWM(0), 0x00}, + { IS31FL319X_PWM(1), 0x00}, + { IS31FL319X_PWM(2), 0x00}, + { IS31FL319X_PWM(3), 0x00}, + { IS31FL319X_PWM(4), 0x00}, + { IS31FL319X_PWM(5), 0x00}, + { IS31FL319X_PWM(6), 0x00}, + { IS31FL319X_PWM(7), 0x00}, + { IS31FL319X_PWM(8), 0x00}, +}; + +static struct regmap_config regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = IS31FL319X_REG_CNT, + .cache_type = REGCACHE_FLAT, + .readable_reg = is31fl319x_readable_reg, + .volatile_reg = is31fl319x_volatile_reg, + .reg_defaults = is31fl319x_reg_defaults, + .num_reg_defaults = ARRAY_SIZE(is31fl319x_reg_defaults), +}; + +static inline int is31fl319x_microamp_to_cs(struct device *dev, u32 microamp) +{ /* round down to nearest supported value (range check done by caller) */ + u32 step = microamp / IS31FL319X_CURRENT_STEP; + + return ((IS31FL319X_CONFIG2_CS_STEP_REF - step) & + IS31FL319X_CONFIG2_CS_MASK) << + IS31FL319X_CONFIG2_CS_SHIFT; /* CS encoding */ +} + +static inline int is31fl319x_db_to_gain(u32 dezibel) +{ /* round down to nearest supported value (range check done by caller) */ + return dezibel / IS31FL319X_AUDIO_GAIN_DB_STEP; +} + +static int is31fl319x_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct is31fl319x_chip *is31; + struct device *dev = &client->dev; + struct i2c_adapter *adapter = to_i2c_adapter(dev->parent); + int err; + int i = 0; + u32 aggregated_led_microamp = IS31FL319X_CURRENT_MAX; + + if (!i2c_check_functionality(adapter, I2C_FUNC_I2C)) + return -EIO; + + is31 = devm_kzalloc(&client->dev, sizeof(*is31), GFP_KERNEL); + if (!is31) + return -ENOMEM; + + mutex_init(&is31->lock); + + err = is31fl319x_parse_dt(&client->dev, is31); + if (err) + goto free_mutex; + + is31->client = client; + is31->regmap = devm_regmap_init_i2c(client, ®map_config); + if (IS_ERR(is31->regmap)) { + dev_err(&client->dev, "failed to allocate register map\n"); + err = PTR_ERR(is31->regmap); + goto free_mutex; + } + + i2c_set_clientdata(client, is31); + + /* check for write-reply from chip (we can't read any registers) */ + err = regmap_write(is31->regmap, IS31FL319X_RESET, 0x00); + if (err < 0) { + dev_err(&client->dev, "no response from chip write: err = %d\n", + err); + err = -EIO; /* does not answer */ + goto free_mutex; + } + + /* + * Kernel conventions require per-LED led-max-microamp property. + * But the chip does not allow to limit individual LEDs. + * So we take minimum from all subnodes for safety of hardware. + */ + for (i = 0; i < is31->cdef->num_leds; i++) + if (is31->leds[i].configured && + is31->leds[i].max_microamp < aggregated_led_microamp) + aggregated_led_microamp = is31->leds[i].max_microamp; + + regmap_write(is31->regmap, IS31FL319X_CONFIG2, + is31fl319x_microamp_to_cs(dev, aggregated_led_microamp) | + is31fl319x_db_to_gain(is31->audio_gain_db)); + + for (i = 0; i < is31->cdef->num_leds; i++) { + struct is31fl319x_led *led = &is31->leds[i]; + + if (!led->configured) + continue; + + led->chip = is31; + led->cdev.brightness_set_blocking = is31fl319x_brightness_set; + + err = devm_led_classdev_register(&client->dev, &led->cdev); + if (err < 0) + goto free_mutex; + } + + return 0; + +free_mutex: + mutex_destroy(&is31->lock); + return err; +} + +static int is31fl319x_remove(struct i2c_client *client) +{ + struct is31fl319x_chip *is31 = i2c_get_clientdata(client); + + mutex_destroy(&is31->lock); + return 0; +} + +/* + * i2c-core (and modalias) requires that id_table be properly filled, + * even though it is not used for DeviceTree based instantiation. + */ +static const struct i2c_device_id is31fl319x_id[] = { + { "is31fl3190" }, + { "is31fl3191" }, + { "is31fl3193" }, + { "is31fl3196" }, + { "is31fl3199" }, + { "sn3199" }, + {}, +}; +MODULE_DEVICE_TABLE(i2c, is31fl319x_id); + +static struct i2c_driver is31fl319x_driver = { + .driver = { + .name = "leds-is31fl319x", + .of_match_table = of_match_ptr(of_is31fl319x_match), + }, + .probe = is31fl319x_probe, + .remove = is31fl319x_remove, + .id_table = is31fl319x_id, +}; + +module_i2c_driver(is31fl319x_driver); + +MODULE_AUTHOR("H. Nikolaus Schaller <hns@goldelico.com>"); +MODULE_AUTHOR("Andrey Utkin <andrey_utkin@fastmail.com>"); +MODULE_DESCRIPTION("IS31FL319X LED driver"); +MODULE_LICENSE("GPL v2"); |