| /* |
| * LED driver for WM831x status LEDs |
| * |
| * Copyright(C) 2009 Wolfson Microelectronics PLC. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/init.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 work_struct work; |
| 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_work(struct work_struct *work) |
| { |
| struct wm831x_status *led = container_of(work, struct wm831x_status, |
| work); |
| 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 void wm831x_status_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; |
| schedule_work(&led->work); |
| spin_unlock_irqrestore(&led->value_lock, flags); |
| } |
| |
| 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; |
| |
| /* Always update; if we fail turn off blinking since we expect |
| * a software fallback. */ |
| schedule_work(&led->work); |
| |
| spin_unlock_irqrestore(&led->value_lock, flags); |
| |
| return ret; |
| } |
| |
| static const char * const led_src_texts[] = { |
| "otp", |
| "power", |
| "charger", |
| "soft", |
| }; |
| |
| static ssize_t wm831x_status_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 wm831x_status_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); |
| char name[20]; |
| int i; |
| size_t len; |
| |
| name[sizeof(name) - 1] = '\0'; |
| strncpy(name, buf, sizeof(name) - 1); |
| len = strlen(name); |
| |
| if (len && name[len - 1] == '\n') |
| name[len - 1] = '\0'; |
| |
| for (i = 0; i < ARRAY_SIZE(led_src_texts); i++) { |
| if (!strcmp(name, led_src_texts[i])) { |
| mutex_lock(&led->mutex); |
| |
| led->src = i; |
| schedule_work(&led->work); |
| |
| mutex_unlock(&led->mutex); |
| } |
| } |
| |
| return size; |
| } |
| |
| static DEVICE_ATTR(src, 0644, wm831x_status_src_show, wm831x_status_src_store); |
| |
| 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_IO, 0); |
| if (res == NULL) { |
| dev_err(&pdev->dev, "No I/O resource\n"); |
| ret = -EINVAL; |
| goto err; |
| } |
| |
| drvdata = devm_kzalloc(&pdev->dev, sizeof(struct wm831x_status), |
| GFP_KERNEL); |
| if (!drvdata) |
| return -ENOMEM; |
| dev_set_drvdata(&pdev->dev, drvdata); |
| |
| drvdata->wm831x = wm831x; |
| drvdata->reg = res->start; |
| |
| if (wm831x->dev->platform_data) |
| chip_pdata = wm831x->dev->platform_data; |
| 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); |
| INIT_WORK(&drvdata->work, wm831x_status_work); |
| 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 = wm831x_status_set; |
| drvdata->cdev.blink_set = wm831x_status_blink_set; |
| |
| ret = led_classdev_register(wm831x->dev, &drvdata->cdev); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "Failed to register LED: %d\n", ret); |
| goto err_led; |
| } |
| |
| ret = device_create_file(drvdata->cdev.dev, &dev_attr_src); |
| if (ret != 0) |
| dev_err(&pdev->dev, |
| "No source control for LED: %d\n", ret); |
| |
| return 0; |
| |
| err_led: |
| led_classdev_unregister(&drvdata->cdev); |
| err: |
| return ret; |
| } |
| |
| static int wm831x_status_remove(struct platform_device *pdev) |
| { |
| struct wm831x_status *drvdata = platform_get_drvdata(pdev); |
| |
| device_remove_file(drvdata->cdev.dev, &dev_attr_src); |
| led_classdev_unregister(&drvdata->cdev); |
| |
| return 0; |
| } |
| |
| static struct platform_driver wm831x_status_driver = { |
| .driver = { |
| .name = "wm831x-status", |
| .owner = THIS_MODULE, |
| }, |
| .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"); |