|  | // SPDX-License-Identifier: GPL-2.0-only | 
|  | /* | 
|  | * LED driver for WM831x status LEDs | 
|  | * | 
|  | * Copyright(C) 2009 Wolfson Microelectronics PLC. | 
|  | */ | 
|  |  | 
|  | #include <linux/kernel.h> | 
|  | #include <linux/platform_device.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/leds.h> | 
|  | #include <linux/err.h> | 
|  | #include <linux/mfd/wm831x/core.h> | 
|  | #include <linux/mfd/wm831x/pdata.h> | 
|  | #include <linux/mfd/wm831x/status.h> | 
|  | #include <linux/module.h> | 
|  |  | 
|  |  | 
|  | struct wm831x_status { | 
|  | struct led_classdev cdev; | 
|  | struct wm831x *wm831x; | 
|  | struct mutex mutex; | 
|  |  | 
|  | spinlock_t value_lock; | 
|  | int reg;     /* Control register */ | 
|  | int reg_val; /* Control register value */ | 
|  |  | 
|  | int blink; | 
|  | int blink_time; | 
|  | int blink_cyc; | 
|  | int src; | 
|  | enum led_brightness brightness; | 
|  | }; | 
|  |  | 
|  | #define to_wm831x_status(led_cdev) \ | 
|  | container_of(led_cdev, struct wm831x_status, cdev) | 
|  |  | 
|  | static void wm831x_status_set(struct wm831x_status *led) | 
|  | { | 
|  | unsigned long flags; | 
|  |  | 
|  | mutex_lock(&led->mutex); | 
|  |  | 
|  | led->reg_val &= ~(WM831X_LED_SRC_MASK | WM831X_LED_MODE_MASK | | 
|  | WM831X_LED_DUTY_CYC_MASK | WM831X_LED_DUR_MASK); | 
|  |  | 
|  | spin_lock_irqsave(&led->value_lock, flags); | 
|  |  | 
|  | led->reg_val |= led->src << WM831X_LED_SRC_SHIFT; | 
|  | if (led->blink) { | 
|  | led->reg_val |= 2 << WM831X_LED_MODE_SHIFT; | 
|  | led->reg_val |= led->blink_time << WM831X_LED_DUR_SHIFT; | 
|  | led->reg_val |= led->blink_cyc; | 
|  | } else { | 
|  | if (led->brightness != LED_OFF) | 
|  | led->reg_val |= 1 << WM831X_LED_MODE_SHIFT; | 
|  | } | 
|  |  | 
|  | spin_unlock_irqrestore(&led->value_lock, flags); | 
|  |  | 
|  | wm831x_reg_write(led->wm831x, led->reg, led->reg_val); | 
|  |  | 
|  | mutex_unlock(&led->mutex); | 
|  | } | 
|  |  | 
|  | static int wm831x_status_brightness_set(struct led_classdev *led_cdev, | 
|  | enum led_brightness value) | 
|  | { | 
|  | struct wm831x_status *led = to_wm831x_status(led_cdev); | 
|  | unsigned long flags; | 
|  |  | 
|  | spin_lock_irqsave(&led->value_lock, flags); | 
|  | led->brightness = value; | 
|  | if (value == LED_OFF) | 
|  | led->blink = 0; | 
|  | spin_unlock_irqrestore(&led->value_lock, flags); | 
|  | wm831x_status_set(led); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int wm831x_status_blink_set(struct led_classdev *led_cdev, | 
|  | unsigned long *delay_on, | 
|  | unsigned long *delay_off) | 
|  | { | 
|  | struct wm831x_status *led = to_wm831x_status(led_cdev); | 
|  | unsigned long flags; | 
|  | int ret = 0; | 
|  |  | 
|  | /* Pick some defaults if we've not been given times */ | 
|  | if (*delay_on == 0 && *delay_off == 0) { | 
|  | *delay_on = 250; | 
|  | *delay_off = 250; | 
|  | } | 
|  |  | 
|  | spin_lock_irqsave(&led->value_lock, flags); | 
|  |  | 
|  | /* We only have a limited selection of settings, see if we can | 
|  | * support the configuration we're being given */ | 
|  | switch (*delay_on) { | 
|  | case 1000: | 
|  | led->blink_time = 0; | 
|  | break; | 
|  | case 250: | 
|  | led->blink_time = 1; | 
|  | break; | 
|  | case 125: | 
|  | led->blink_time = 2; | 
|  | break; | 
|  | case 62: | 
|  | case 63: | 
|  | /* Actually 62.5ms */ | 
|  | led->blink_time = 3; | 
|  | break; | 
|  | default: | 
|  | ret = -EINVAL; | 
|  | break; | 
|  | } | 
|  |  | 
|  | if (ret == 0) { | 
|  | switch (*delay_off / *delay_on) { | 
|  | case 1: | 
|  | led->blink_cyc = 0; | 
|  | break; | 
|  | case 3: | 
|  | led->blink_cyc = 1; | 
|  | break; | 
|  | case 4: | 
|  | led->blink_cyc = 2; | 
|  | break; | 
|  | case 8: | 
|  | led->blink_cyc = 3; | 
|  | break; | 
|  | default: | 
|  | ret = -EINVAL; | 
|  | break; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (ret == 0) | 
|  | led->blink = 1; | 
|  | else | 
|  | led->blink = 0; | 
|  |  | 
|  | spin_unlock_irqrestore(&led->value_lock, flags); | 
|  | wm831x_status_set(led); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static const char * const led_src_texts[] = { | 
|  | "otp", | 
|  | "power", | 
|  | "charger", | 
|  | "soft", | 
|  | }; | 
|  |  | 
|  | static ssize_t src_show(struct device *dev, | 
|  | struct device_attribute *attr, char *buf) | 
|  | { | 
|  | struct led_classdev *led_cdev = dev_get_drvdata(dev); | 
|  | struct wm831x_status *led = to_wm831x_status(led_cdev); | 
|  | int i; | 
|  | ssize_t ret = 0; | 
|  |  | 
|  | mutex_lock(&led->mutex); | 
|  |  | 
|  | for (i = 0; i < ARRAY_SIZE(led_src_texts); i++) | 
|  | if (i == led->src) | 
|  | ret += sprintf(&buf[ret], "[%s] ", led_src_texts[i]); | 
|  | else | 
|  | ret += sprintf(&buf[ret], "%s ", led_src_texts[i]); | 
|  |  | 
|  | mutex_unlock(&led->mutex); | 
|  |  | 
|  | ret += sprintf(&buf[ret], "\n"); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static ssize_t src_store(struct device *dev, | 
|  | struct device_attribute *attr, | 
|  | const char *buf, size_t size) | 
|  | { | 
|  | struct led_classdev *led_cdev = dev_get_drvdata(dev); | 
|  | struct wm831x_status *led = to_wm831x_status(led_cdev); | 
|  | int i; | 
|  |  | 
|  | i = sysfs_match_string(led_src_texts, buf); | 
|  | if (i >= 0) { | 
|  | mutex_lock(&led->mutex); | 
|  | led->src = i; | 
|  | mutex_unlock(&led->mutex); | 
|  | wm831x_status_set(led); | 
|  | } | 
|  |  | 
|  | return size; | 
|  | } | 
|  |  | 
|  | static DEVICE_ATTR_RW(src); | 
|  |  | 
|  | static struct attribute *wm831x_status_attrs[] = { | 
|  | &dev_attr_src.attr, | 
|  | NULL | 
|  | }; | 
|  | ATTRIBUTE_GROUPS(wm831x_status); | 
|  |  | 
|  | static int wm831x_status_probe(struct platform_device *pdev) | 
|  | { | 
|  | struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); | 
|  | struct wm831x_pdata *chip_pdata; | 
|  | struct wm831x_status_pdata pdata; | 
|  | struct wm831x_status *drvdata; | 
|  | struct resource *res; | 
|  | int id = pdev->id % ARRAY_SIZE(chip_pdata->status); | 
|  | int ret; | 
|  |  | 
|  | res = platform_get_resource(pdev, IORESOURCE_REG, 0); | 
|  | if (res == NULL) { | 
|  | dev_err(&pdev->dev, "No register resource\n"); | 
|  | return -EINVAL; | 
|  | } | 
|  |  | 
|  | drvdata = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_status), | 
|  | GFP_KERNEL); | 
|  | if (!drvdata) | 
|  | return -ENOMEM; | 
|  |  | 
|  | drvdata->wm831x = wm831x; | 
|  | drvdata->reg = res->start; | 
|  |  | 
|  | if (dev_get_platdata(wm831x->dev)) | 
|  | chip_pdata = dev_get_platdata(wm831x->dev); | 
|  | else | 
|  | chip_pdata = NULL; | 
|  |  | 
|  | memset(&pdata, 0, sizeof(pdata)); | 
|  | if (chip_pdata && chip_pdata->status[id]) | 
|  | memcpy(&pdata, chip_pdata->status[id], sizeof(pdata)); | 
|  | else | 
|  | pdata.name = dev_name(&pdev->dev); | 
|  |  | 
|  | mutex_init(&drvdata->mutex); | 
|  | spin_lock_init(&drvdata->value_lock); | 
|  |  | 
|  | /* We cache the configuration register and read startup values | 
|  | * from it. */ | 
|  | drvdata->reg_val = wm831x_reg_read(wm831x, drvdata->reg); | 
|  |  | 
|  | if (drvdata->reg_val & WM831X_LED_MODE_MASK) | 
|  | drvdata->brightness = LED_FULL; | 
|  | else | 
|  | drvdata->brightness = LED_OFF; | 
|  |  | 
|  | /* Set a default source if configured, otherwise leave the | 
|  | * current hardware setting. | 
|  | */ | 
|  | if (pdata.default_src == WM831X_STATUS_PRESERVE) { | 
|  | drvdata->src = drvdata->reg_val; | 
|  | drvdata->src &= WM831X_LED_SRC_MASK; | 
|  | drvdata->src >>= WM831X_LED_SRC_SHIFT; | 
|  | } else { | 
|  | drvdata->src = pdata.default_src - 1; | 
|  | } | 
|  |  | 
|  | drvdata->cdev.name = pdata.name; | 
|  | drvdata->cdev.default_trigger = pdata.default_trigger; | 
|  | drvdata->cdev.brightness_set_blocking = wm831x_status_brightness_set; | 
|  | drvdata->cdev.blink_set = wm831x_status_blink_set; | 
|  | drvdata->cdev.groups = wm831x_status_groups; | 
|  |  | 
|  | ret = led_classdev_register(wm831x->dev, &drvdata->cdev); | 
|  | if (ret < 0) { | 
|  | dev_err(&pdev->dev, "Failed to register LED: %d\n", ret); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | platform_set_drvdata(pdev, drvdata); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static int wm831x_status_remove(struct platform_device *pdev) | 
|  | { | 
|  | struct wm831x_status *drvdata = platform_get_drvdata(pdev); | 
|  |  | 
|  | led_classdev_unregister(&drvdata->cdev); | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct platform_driver wm831x_status_driver = { | 
|  | .driver = { | 
|  | .name = "wm831x-status", | 
|  | }, | 
|  | .probe = wm831x_status_probe, | 
|  | .remove = wm831x_status_remove, | 
|  | }; | 
|  |  | 
|  | module_platform_driver(wm831x_status_driver); | 
|  |  | 
|  | MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); | 
|  | MODULE_DESCRIPTION("WM831x status LED driver"); | 
|  | MODULE_LICENSE("GPL"); | 
|  | MODULE_ALIAS("platform:wm831x-status"); |