diff options
Diffstat (limited to 'drivers/leds/leds-sc27xx-bltc.c')
| -rw-r--r-- | drivers/leds/leds-sc27xx-bltc.c | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/drivers/leds/leds-sc27xx-bltc.c b/drivers/leds/leds-sc27xx-bltc.c new file mode 100644 index 000000000..e199ea15e --- /dev/null +++ b/drivers/leds/leds-sc27xx-bltc.c @@ -0,0 +1,361 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2018 Spreadtrum Communications Inc. + +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +/* PMIC global control register definition */ +#define SC27XX_MODULE_EN0 0xc08 +#define SC27XX_CLK_EN0 0xc18 +#define SC27XX_RGB_CTRL 0xebc + +#define SC27XX_BLTC_EN BIT(9) +#define SC27XX_RTC_EN BIT(7) +#define SC27XX_RGB_PD BIT(0) + +/* Breathing light controller register definition */ +#define SC27XX_LEDS_CTRL 0x00 +#define SC27XX_LEDS_PRESCALE 0x04 +#define SC27XX_LEDS_DUTY 0x08 +#define SC27XX_LEDS_CURVE0 0x0c +#define SC27XX_LEDS_CURVE1 0x10 + +#define SC27XX_CTRL_SHIFT 4 +#define SC27XX_LED_RUN BIT(0) +#define SC27XX_LED_TYPE BIT(1) + +#define SC27XX_DUTY_SHIFT 8 +#define SC27XX_DUTY_MASK GENMASK(15, 0) +#define SC27XX_MOD_MASK GENMASK(7, 0) + +#define SC27XX_CURVE_SHIFT 8 +#define SC27XX_CURVE_L_MASK GENMASK(7, 0) +#define SC27XX_CURVE_H_MASK GENMASK(15, 8) + +#define SC27XX_LEDS_OFFSET 0x10 +#define SC27XX_LEDS_MAX 3 +#define SC27XX_LEDS_PATTERN_CNT 4 +/* Stage duration step, in milliseconds */ +#define SC27XX_LEDS_STEP 125 +/* Minimum and maximum duration, in milliseconds */ +#define SC27XX_DELTA_T_MIN SC27XX_LEDS_STEP +#define SC27XX_DELTA_T_MAX (SC27XX_LEDS_STEP * 255) + +struct sc27xx_led { + struct fwnode_handle *fwnode; + struct led_classdev ldev; + struct sc27xx_led_priv *priv; + u8 line; + bool active; +}; + +struct sc27xx_led_priv { + struct sc27xx_led leds[SC27XX_LEDS_MAX]; + struct regmap *regmap; + struct mutex lock; + u32 base; +}; + +#define to_sc27xx_led(ldev) \ + container_of(ldev, struct sc27xx_led, ldev) + +static int sc27xx_led_init(struct regmap *regmap) +{ + int err; + + err = regmap_update_bits(regmap, SC27XX_MODULE_EN0, SC27XX_BLTC_EN, + SC27XX_BLTC_EN); + if (err) + return err; + + err = regmap_update_bits(regmap, SC27XX_CLK_EN0, SC27XX_RTC_EN, + SC27XX_RTC_EN); + if (err) + return err; + + return regmap_update_bits(regmap, SC27XX_RGB_CTRL, SC27XX_RGB_PD, 0); +} + +static u32 sc27xx_led_get_offset(struct sc27xx_led *leds) +{ + return leds->priv->base + SC27XX_LEDS_OFFSET * leds->line; +} + +static int sc27xx_led_enable(struct sc27xx_led *leds, enum led_brightness value) +{ + u32 base = sc27xx_led_get_offset(leds); + u32 ctrl_base = leds->priv->base + SC27XX_LEDS_CTRL; + u8 ctrl_shift = SC27XX_CTRL_SHIFT * leds->line; + struct regmap *regmap = leds->priv->regmap; + int err; + + err = regmap_update_bits(regmap, base + SC27XX_LEDS_DUTY, + SC27XX_DUTY_MASK, + (value << SC27XX_DUTY_SHIFT) | + SC27XX_MOD_MASK); + if (err) + return err; + + return regmap_update_bits(regmap, ctrl_base, + (SC27XX_LED_RUN | SC27XX_LED_TYPE) << ctrl_shift, + (SC27XX_LED_RUN | SC27XX_LED_TYPE) << ctrl_shift); +} + +static int sc27xx_led_disable(struct sc27xx_led *leds) +{ + struct regmap *regmap = leds->priv->regmap; + u32 ctrl_base = leds->priv->base + SC27XX_LEDS_CTRL; + u8 ctrl_shift = SC27XX_CTRL_SHIFT * leds->line; + + return regmap_update_bits(regmap, ctrl_base, + (SC27XX_LED_RUN | SC27XX_LED_TYPE) << ctrl_shift, 0); +} + +static int sc27xx_led_set(struct led_classdev *ldev, enum led_brightness value) +{ + struct sc27xx_led *leds = to_sc27xx_led(ldev); + int err; + + mutex_lock(&leds->priv->lock); + + if (value == LED_OFF) + err = sc27xx_led_disable(leds); + else + err = sc27xx_led_enable(leds, value); + + mutex_unlock(&leds->priv->lock); + + return err; +} + +static void sc27xx_led_clamp_align_delta_t(u32 *delta_t) +{ + u32 v, offset, t = *delta_t; + + v = t + SC27XX_LEDS_STEP / 2; + v = clamp_t(u32, v, SC27XX_DELTA_T_MIN, SC27XX_DELTA_T_MAX); + offset = v - SC27XX_DELTA_T_MIN; + offset = SC27XX_LEDS_STEP * (offset / SC27XX_LEDS_STEP); + + *delta_t = SC27XX_DELTA_T_MIN + offset; +} + +static int sc27xx_led_pattern_clear(struct led_classdev *ldev) +{ + struct sc27xx_led *leds = to_sc27xx_led(ldev); + struct regmap *regmap = leds->priv->regmap; + u32 base = sc27xx_led_get_offset(leds); + u32 ctrl_base = leds->priv->base + SC27XX_LEDS_CTRL; + u8 ctrl_shift = SC27XX_CTRL_SHIFT * leds->line; + int err; + + mutex_lock(&leds->priv->lock); + + /* Reset the rise, high, fall and low time to zero. */ + regmap_write(regmap, base + SC27XX_LEDS_CURVE0, 0); + regmap_write(regmap, base + SC27XX_LEDS_CURVE1, 0); + + err = regmap_update_bits(regmap, ctrl_base, + (SC27XX_LED_RUN | SC27XX_LED_TYPE) << ctrl_shift, 0); + + ldev->brightness = LED_OFF; + + mutex_unlock(&leds->priv->lock); + + return err; +} + +static int sc27xx_led_pattern_set(struct led_classdev *ldev, + struct led_pattern *pattern, + u32 len, int repeat) +{ + struct sc27xx_led *leds = to_sc27xx_led(ldev); + u32 base = sc27xx_led_get_offset(leds); + u32 ctrl_base = leds->priv->base + SC27XX_LEDS_CTRL; + u8 ctrl_shift = SC27XX_CTRL_SHIFT * leds->line; + struct regmap *regmap = leds->priv->regmap; + int err; + + /* + * Must contain 4 tuples to configure the rise time, high time, fall + * time and low time to enable the breathing mode. + */ + if (len != SC27XX_LEDS_PATTERN_CNT) + return -EINVAL; + + mutex_lock(&leds->priv->lock); + + sc27xx_led_clamp_align_delta_t(&pattern[0].delta_t); + err = regmap_update_bits(regmap, base + SC27XX_LEDS_CURVE0, + SC27XX_CURVE_L_MASK, + pattern[0].delta_t / SC27XX_LEDS_STEP); + if (err) + goto out; + + sc27xx_led_clamp_align_delta_t(&pattern[1].delta_t); + err = regmap_update_bits(regmap, base + SC27XX_LEDS_CURVE1, + SC27XX_CURVE_L_MASK, + pattern[1].delta_t / SC27XX_LEDS_STEP); + if (err) + goto out; + + sc27xx_led_clamp_align_delta_t(&pattern[2].delta_t); + err = regmap_update_bits(regmap, base + SC27XX_LEDS_CURVE0, + SC27XX_CURVE_H_MASK, + (pattern[2].delta_t / SC27XX_LEDS_STEP) << + SC27XX_CURVE_SHIFT); + if (err) + goto out; + + sc27xx_led_clamp_align_delta_t(&pattern[3].delta_t); + err = regmap_update_bits(regmap, base + SC27XX_LEDS_CURVE1, + SC27XX_CURVE_H_MASK, + (pattern[3].delta_t / SC27XX_LEDS_STEP) << + SC27XX_CURVE_SHIFT); + if (err) + goto out; + + err = regmap_update_bits(regmap, base + SC27XX_LEDS_DUTY, + SC27XX_DUTY_MASK, + (pattern[1].brightness << SC27XX_DUTY_SHIFT) | + SC27XX_MOD_MASK); + if (err) + goto out; + + /* Enable the LED breathing mode */ + err = regmap_update_bits(regmap, ctrl_base, + SC27XX_LED_RUN << ctrl_shift, + SC27XX_LED_RUN << ctrl_shift); + if (!err) + ldev->brightness = pattern[1].brightness; + +out: + mutex_unlock(&leds->priv->lock); + + return err; +} + +static int sc27xx_led_register(struct device *dev, struct sc27xx_led_priv *priv) +{ + int i, err; + + err = sc27xx_led_init(priv->regmap); + if (err) + return err; + + for (i = 0; i < SC27XX_LEDS_MAX; i++) { + struct sc27xx_led *led = &priv->leds[i]; + struct led_init_data init_data = {}; + + if (!led->active) + continue; + + led->line = i; + led->priv = priv; + led->ldev.brightness_set_blocking = sc27xx_led_set; + led->ldev.pattern_set = sc27xx_led_pattern_set; + led->ldev.pattern_clear = sc27xx_led_pattern_clear; + led->ldev.default_trigger = "pattern"; + + init_data.fwnode = led->fwnode; + init_data.devicename = "sc27xx"; + init_data.default_label = ":"; + + err = devm_led_classdev_register_ext(dev, &led->ldev, + &init_data); + if (err) + return err; + } + + return 0; +} + +static int sc27xx_led_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev_of_node(dev), *child; + struct sc27xx_led_priv *priv; + u32 base, count, reg; + int err; + + count = of_get_available_child_count(np); + if (!count || count > SC27XX_LEDS_MAX) + return -EINVAL; + + err = of_property_read_u32(np, "reg", &base); + if (err) { + dev_err(dev, "fail to get reg of property\n"); + return err; + } + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + platform_set_drvdata(pdev, priv); + mutex_init(&priv->lock); + priv->base = base; + priv->regmap = dev_get_regmap(dev->parent, NULL); + if (!priv->regmap) { + err = -ENODEV; + dev_err(dev, "failed to get regmap: %d\n", err); + return err; + } + + for_each_available_child_of_node(np, child) { + err = of_property_read_u32(child, "reg", ®); + if (err) { + of_node_put(child); + mutex_destroy(&priv->lock); + return err; + } + + if (reg >= SC27XX_LEDS_MAX || priv->leds[reg].active) { + of_node_put(child); + mutex_destroy(&priv->lock); + return -EINVAL; + } + + priv->leds[reg].fwnode = of_fwnode_handle(child); + priv->leds[reg].active = true; + } + + err = sc27xx_led_register(dev, priv); + if (err) + mutex_destroy(&priv->lock); + + return err; +} + +static int sc27xx_led_remove(struct platform_device *pdev) +{ + struct sc27xx_led_priv *priv = platform_get_drvdata(pdev); + + mutex_destroy(&priv->lock); + return 0; +} + +static const struct of_device_id sc27xx_led_of_match[] = { + { .compatible = "sprd,sc2731-bltc", }, + { } +}; +MODULE_DEVICE_TABLE(of, sc27xx_led_of_match); + +static struct platform_driver sc27xx_led_driver = { + .driver = { + .name = "sprd-bltc", + .of_match_table = sc27xx_led_of_match, + }, + .probe = sc27xx_led_probe, + .remove = sc27xx_led_remove, +}; + +module_platform_driver(sc27xx_led_driver); + +MODULE_DESCRIPTION("Spreadtrum SC27xx breathing light controller driver"); +MODULE_AUTHOR("Xiaotong Lu <xiaotong.lu@spreadtrum.com>"); +MODULE_AUTHOR("Baolin Wang <baolin.wang@linaro.org>"); +MODULE_LICENSE("GPL v2"); |