| Ilya Petrov | 97cc265 | 2011-09-27 19:00:44 +0200 | [diff] [blame] | 1 | /* |
| 2 | * nvec_leds: LED driver for a NVIDIA compliant embedded controller |
| 3 | * |
| 4 | * Copyright (C) 2011 The AC100 Kernel Team <ac100@lists.launchpad.net> |
| 5 | * |
| 6 | * Authors: Ilya Petrov <ilya.muromec@gmail.com> |
| 7 | * |
| 8 | * This file is subject to the terms and conditions of the GNU General Public |
| 9 | * License. See the file "COPYING" in the main directory of this archive |
| 10 | * for more details. |
| 11 | * |
| 12 | */ |
| 13 | |
| 14 | #include <linux/module.h> |
| 15 | #include <linux/err.h> |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/leds.h> |
| 18 | #include <linux/platform_device.h> |
| 19 | #include "nvec.h" |
| 20 | |
| 21 | #define to_nvec_led(led_cdev) \ |
| 22 | container_of(led_cdev, struct nvec_led, cdev) |
| 23 | |
| 24 | #define NVEC_LED_REQ {'\x0d', '\x10', '\x45', '\x10', '\x00'} |
| 25 | |
| 26 | #define NVEC_LED_MAX 8 |
| 27 | |
| 28 | struct nvec_led { |
| 29 | struct led_classdev cdev; |
| 30 | struct nvec_chip *nvec; |
| 31 | }; |
| 32 | |
| 33 | static void nvec_led_brightness_set(struct led_classdev *led_cdev, |
| 34 | enum led_brightness value) |
| 35 | { |
| 36 | struct nvec_led *led = to_nvec_led(led_cdev); |
| 37 | unsigned char buf[] = NVEC_LED_REQ; |
| 38 | buf[4] = value; |
| 39 | |
| 40 | nvec_write_async(led->nvec, buf, sizeof(buf)); |
| 41 | |
| 42 | led->cdev.brightness = value; |
| 43 | |
| 44 | } |
| 45 | |
| 46 | static int __devinit nvec_led_probe(struct platform_device *pdev) |
| 47 | { |
| 48 | struct nvec_chip *nvec = dev_get_drvdata(pdev->dev.parent); |
| 49 | struct nvec_led *led; |
| 50 | int ret = 0; |
| 51 | |
| 52 | led = kzalloc(sizeof(*led), GFP_KERNEL); |
| 53 | if (led == NULL) |
| 54 | return -ENOMEM; |
| 55 | |
| 56 | led->cdev.max_brightness = NVEC_LED_MAX; |
| 57 | |
| 58 | led->cdev.brightness_set = nvec_led_brightness_set; |
| 59 | led->cdev.name = "nvec-led"; |
| 60 | led->cdev.flags |= LED_CORE_SUSPENDRESUME; |
| 61 | led->nvec = nvec; |
| 62 | |
| 63 | platform_set_drvdata(pdev, led); |
| 64 | |
| 65 | ret = led_classdev_register(&pdev->dev, &led->cdev); |
| 66 | if (ret < 0) |
| 67 | goto err_led; |
| 68 | |
| 69 | /* to expose the default value to userspace */ |
| 70 | led->cdev.brightness = 0; |
| 71 | |
| 72 | return 0; |
| 73 | |
| 74 | err_led: |
| 75 | kfree(led); |
| 76 | return ret; |
| 77 | } |
| 78 | |
| 79 | static int __devexit nvec_led_remove(struct platform_device *pdev) |
| 80 | { |
| 81 | struct nvec_led *led = platform_get_drvdata(pdev); |
| 82 | |
| 83 | led_classdev_unregister(&led->cdev); |
| 84 | kfree(led); |
| 85 | return 0; |
| 86 | } |
| 87 | |
| 88 | static struct platform_driver nvec_led_driver = { |
| 89 | .probe = nvec_led_probe, |
| 90 | .remove = __devexit_p(nvec_led_remove), |
| 91 | .driver = { |
| 92 | .name = "nvec-leds", |
| 93 | .owner = THIS_MODULE, |
| 94 | }, |
| 95 | }; |
| 96 | |
| 97 | static int __init nvec_led_init(void) |
| 98 | { |
| 99 | return platform_driver_register(&nvec_led_driver); |
| 100 | } |
| 101 | |
| 102 | module_init(nvec_led_init); |
| 103 | |
| 104 | static void __exit nvec_led_exit(void) |
| 105 | { |
| 106 | platform_driver_unregister(&nvec_led_driver); |
| 107 | } |
| 108 | |
| 109 | module_exit(nvec_led_exit); |
| 110 | |
| 111 | MODULE_AUTHOR("Ilya Petrov <ilya.muromec@gmail.com>"); |
| 112 | MODULE_DESCRIPTION("Tegra NVEC LED driver"); |
| 113 | MODULE_LICENSE("GPL"); |
| 114 | MODULE_ALIAS("platform:nvec-leds"); |