Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * LCD Lowlevel Control Abstraction |
| 3 | * |
| 4 | * Copyright (C) 2003,2004 Hewlett-Packard Company |
| 5 | * |
| 6 | */ |
| 7 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | #include <linux/module.h> |
| 9 | #include <linux/init.h> |
| 10 | #include <linux/device.h> |
| 11 | #include <linux/lcd.h> |
| 12 | #include <linux/notifier.h> |
| 13 | #include <linux/ctype.h> |
| 14 | #include <linux/err.h> |
| 15 | #include <linux/fb.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | |
James Simmons | 3d5eead | 2006-12-08 02:40:47 -0800 | [diff] [blame] | 17 | #if defined(CONFIG_FB) || (defined(CONFIG_FB_MODULE) && \ |
| 18 | defined(CONFIG_LCD_CLASS_DEVICE_MODULE)) |
| 19 | /* This callback gets called when something important happens inside a |
| 20 | * framebuffer driver. We're looking if that important event is blanking, |
| 21 | * and if it is, we're switching lcd power as well ... |
| 22 | */ |
| 23 | static int fb_notifier_callback(struct notifier_block *self, |
| 24 | unsigned long event, void *data) |
| 25 | { |
| 26 | struct lcd_device *ld; |
| 27 | struct fb_event *evdata = data; |
| 28 | |
| 29 | /* If we aren't interested in this event, skip it immediately ... */ |
| 30 | if (event != FB_EVENT_BLANK) |
| 31 | return 0; |
| 32 | |
| 33 | ld = container_of(self, struct lcd_device, fb_notif); |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 34 | mutex_lock(&ld->ops_lock); |
| 35 | if (ld->ops) |
| 36 | if (!ld->ops->check_fb || ld->ops->check_fb(evdata->info)) |
| 37 | ld->ops->set_power(ld, *(int *)evdata->data); |
| 38 | mutex_unlock(&ld->ops_lock); |
James Simmons | 3d5eead | 2006-12-08 02:40:47 -0800 | [diff] [blame] | 39 | return 0; |
| 40 | } |
| 41 | |
| 42 | static int lcd_register_fb(struct lcd_device *ld) |
| 43 | { |
| 44 | memset(&ld->fb_notif, 0, sizeof(&ld->fb_notif)); |
| 45 | ld->fb_notif.notifier_call = fb_notifier_callback; |
| 46 | return fb_register_client(&ld->fb_notif); |
| 47 | } |
| 48 | |
| 49 | static void lcd_unregister_fb(struct lcd_device *ld) |
| 50 | { |
| 51 | fb_unregister_client(&ld->fb_notif); |
| 52 | } |
| 53 | #else |
| 54 | static int lcd_register_fb(struct lcd_device *ld) |
| 55 | { |
| 56 | return 0; |
| 57 | } |
| 58 | |
| 59 | static inline void lcd_unregister_fb(struct lcd_device *ld) |
| 60 | { |
| 61 | } |
| 62 | #endif /* CONFIG_FB */ |
| 63 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | static ssize_t lcd_show_power(struct class_device *cdev, char *buf) |
| 65 | { |
| 66 | int rc; |
| 67 | struct lcd_device *ld = to_lcd_device(cdev); |
| 68 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 69 | mutex_lock(&ld->ops_lock); |
| 70 | if (ld->ops && ld->ops->get_power) |
| 71 | rc = sprintf(buf, "%d\n", ld->ops->get_power(ld)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | else |
| 73 | rc = -ENXIO; |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 74 | mutex_unlock(&ld->ops_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 75 | |
| 76 | return rc; |
| 77 | } |
| 78 | |
| 79 | static ssize_t lcd_store_power(struct class_device *cdev, const char *buf, size_t count) |
| 80 | { |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 81 | int rc = -ENXIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | char *endp; |
| 83 | struct lcd_device *ld = to_lcd_device(cdev); |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 84 | int power = simple_strtoul(buf, &endp, 0); |
| 85 | size_t size = endp - buf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 86 | |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 87 | if (*endp && isspace(*endp)) |
| 88 | size++; |
| 89 | if (size != count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | return -EINVAL; |
| 91 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 92 | mutex_lock(&ld->ops_lock); |
| 93 | if (ld->ops && ld->ops->set_power) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 94 | pr_debug("lcd: set power to %d\n", power); |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 95 | ld->ops->set_power(ld, power); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 96 | rc = count; |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 97 | } |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 98 | mutex_unlock(&ld->ops_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 99 | |
| 100 | return rc; |
| 101 | } |
| 102 | |
| 103 | static ssize_t lcd_show_contrast(struct class_device *cdev, char *buf) |
| 104 | { |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 105 | int rc = -ENXIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | struct lcd_device *ld = to_lcd_device(cdev); |
| 107 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 108 | mutex_lock(&ld->ops_lock); |
| 109 | if (ld->ops && ld->ops->get_contrast) |
| 110 | rc = sprintf(buf, "%d\n", ld->ops->get_contrast(ld)); |
| 111 | mutex_unlock(&ld->ops_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | |
| 113 | return rc; |
| 114 | } |
| 115 | |
| 116 | static ssize_t lcd_store_contrast(struct class_device *cdev, const char *buf, size_t count) |
| 117 | { |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 118 | int rc = -ENXIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 119 | char *endp; |
| 120 | struct lcd_device *ld = to_lcd_device(cdev); |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 121 | int contrast = simple_strtoul(buf, &endp, 0); |
| 122 | size_t size = endp - buf; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 124 | if (*endp && isspace(*endp)) |
| 125 | size++; |
| 126 | if (size != count) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 127 | return -EINVAL; |
| 128 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 129 | mutex_lock(&ld->ops_lock); |
| 130 | if (ld->ops && ld->ops->set_contrast) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 131 | pr_debug("lcd: set contrast to %d\n", contrast); |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 132 | ld->ops->set_contrast(ld, contrast); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | rc = count; |
Richard Purdie | 68673af | 2006-05-15 09:44:15 -0700 | [diff] [blame] | 134 | } |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 135 | mutex_unlock(&ld->ops_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 136 | |
| 137 | return rc; |
| 138 | } |
| 139 | |
| 140 | static ssize_t lcd_show_max_contrast(struct class_device *cdev, char *buf) |
| 141 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 142 | struct lcd_device *ld = to_lcd_device(cdev); |
| 143 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 144 | return sprintf(buf, "%d\n", ld->props.max_contrast); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 145 | } |
| 146 | |
| 147 | static void lcd_class_release(struct class_device *dev) |
| 148 | { |
| 149 | struct lcd_device *ld = to_lcd_device(dev); |
| 150 | kfree(ld); |
| 151 | } |
| 152 | |
| 153 | static struct class lcd_class = { |
| 154 | .name = "lcd", |
| 155 | .release = lcd_class_release, |
| 156 | }; |
| 157 | |
| 158 | #define DECLARE_ATTR(_name,_mode,_show,_store) \ |
| 159 | { \ |
| 160 | .attr = { .name = __stringify(_name), .mode = _mode, .owner = THIS_MODULE }, \ |
| 161 | .show = _show, \ |
| 162 | .store = _store, \ |
| 163 | } |
| 164 | |
Helge Deller | d95159c | 2006-12-08 02:40:28 -0800 | [diff] [blame] | 165 | static const struct class_device_attribute lcd_class_device_attributes[] = { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 166 | DECLARE_ATTR(power, 0644, lcd_show_power, lcd_store_power), |
| 167 | DECLARE_ATTR(contrast, 0644, lcd_show_contrast, lcd_store_contrast), |
| 168 | DECLARE_ATTR(max_contrast, 0444, lcd_show_max_contrast, NULL), |
| 169 | }; |
| 170 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | /** |
| 172 | * lcd_device_register - register a new object of lcd_device class. |
| 173 | * @name: the name of the new object(must be the same as the name of the |
| 174 | * respective framebuffer device). |
| 175 | * @devdata: an optional pointer to be stored in the class_device. The |
| 176 | * methods may retrieve it by using class_get_devdata(ld->class_dev). |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 177 | * @ops: the lcd operations structure. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | * |
| 179 | * Creates and registers a new lcd class_device. Returns either an ERR_PTR() |
| 180 | * or a pointer to the newly allocated device. |
| 181 | */ |
| 182 | struct lcd_device *lcd_device_register(const char *name, void *devdata, |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 183 | struct lcd_ops *ops) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | { |
| 185 | int i, rc; |
| 186 | struct lcd_device *new_ld; |
| 187 | |
| 188 | pr_debug("lcd_device_register: name=%s\n", name); |
| 189 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 190 | new_ld = kzalloc(sizeof(struct lcd_device), GFP_KERNEL); |
Dmitry Torokhov | 90968e8 | 2007-02-08 00:12:28 +0000 | [diff] [blame] | 191 | if (!new_ld) |
Jean Delvare | 10ad1b7 | 2006-03-09 17:33:36 -0800 | [diff] [blame] | 192 | return ERR_PTR(-ENOMEM); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 194 | mutex_init(&new_ld->ops_lock); |
Richard Purdie | 28ee086 | 2007-02-08 22:25:09 +0000 | [diff] [blame] | 195 | mutex_init(&new_ld->update_lock); |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 196 | new_ld->ops = ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 197 | new_ld->class_dev.class = &lcd_class; |
| 198 | strlcpy(new_ld->class_dev.class_id, name, KOBJ_NAME_LEN); |
| 199 | class_set_devdata(&new_ld->class_dev, devdata); |
| 200 | |
| 201 | rc = class_device_register(&new_ld->class_dev); |
Dmitry Torokhov | 90968e8 | 2007-02-08 00:12:28 +0000 | [diff] [blame] | 202 | if (rc) { |
Dmitry Torokhov | 2fd5a15 | 2007-02-07 22:25:50 +0000 | [diff] [blame] | 203 | kfree(new_ld); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 204 | return ERR_PTR(rc); |
| 205 | } |
| 206 | |
James Simmons | 3d5eead | 2006-12-08 02:40:47 -0800 | [diff] [blame] | 207 | rc = lcd_register_fb(new_ld); |
Dmitry Torokhov | 2fd5a15 | 2007-02-07 22:25:50 +0000 | [diff] [blame] | 208 | if (rc) { |
| 209 | class_device_unregister(&new_ld->class_dev); |
| 210 | return ERR_PTR(rc); |
| 211 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | |
| 213 | for (i = 0; i < ARRAY_SIZE(lcd_class_device_attributes); i++) { |
| 214 | rc = class_device_create_file(&new_ld->class_dev, |
| 215 | &lcd_class_device_attributes[i]); |
Dmitry Torokhov | 90968e8 | 2007-02-08 00:12:28 +0000 | [diff] [blame] | 216 | if (rc) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 217 | while (--i >= 0) |
| 218 | class_device_remove_file(&new_ld->class_dev, |
| 219 | &lcd_class_device_attributes[i]); |
| 220 | class_device_unregister(&new_ld->class_dev); |
| 221 | /* No need to kfree(new_ld) since release() method was called */ |
| 222 | return ERR_PTR(rc); |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | return new_ld; |
| 227 | } |
| 228 | EXPORT_SYMBOL(lcd_device_register); |
| 229 | |
| 230 | /** |
| 231 | * lcd_device_unregister - unregisters a object of lcd_device class. |
| 232 | * @ld: the lcd device object to be unregistered and freed. |
| 233 | * |
| 234 | * Unregisters a previously registered via lcd_device_register object. |
| 235 | */ |
| 236 | void lcd_device_unregister(struct lcd_device *ld) |
| 237 | { |
| 238 | int i; |
| 239 | |
| 240 | if (!ld) |
| 241 | return; |
| 242 | |
| 243 | pr_debug("lcd_device_unregister: name=%s\n", ld->class_dev.class_id); |
| 244 | |
| 245 | for (i = 0; i < ARRAY_SIZE(lcd_class_device_attributes); i++) |
| 246 | class_device_remove_file(&ld->class_dev, |
| 247 | &lcd_class_device_attributes[i]); |
| 248 | |
Richard Purdie | 599a52d | 2007-02-10 23:07:48 +0000 | [diff] [blame] | 249 | mutex_lock(&ld->ops_lock); |
| 250 | ld->ops = NULL; |
| 251 | mutex_unlock(&ld->ops_lock); |
James Simmons | 3d5eead | 2006-12-08 02:40:47 -0800 | [diff] [blame] | 252 | lcd_unregister_fb(ld); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 253 | class_device_unregister(&ld->class_dev); |
| 254 | } |
| 255 | EXPORT_SYMBOL(lcd_device_unregister); |
| 256 | |
| 257 | static void __exit lcd_class_exit(void) |
| 258 | { |
| 259 | class_unregister(&lcd_class); |
| 260 | } |
| 261 | |
| 262 | static int __init lcd_class_init(void) |
| 263 | { |
| 264 | return class_register(&lcd_class); |
| 265 | } |
| 266 | |
| 267 | /* |
| 268 | * if this is compiled into the kernel, we need to ensure that the |
| 269 | * class is registered before users of the class try to register lcd's |
| 270 | */ |
| 271 | postcore_initcall(lcd_class_init); |
| 272 | module_exit(lcd_class_exit); |
| 273 | |
| 274 | MODULE_LICENSE("GPL"); |
| 275 | MODULE_AUTHOR("Jamey Hicks <jamey.hicks@hp.com>, Andrew Zabolotny <zap@homelink.ru>"); |
| 276 | MODULE_DESCRIPTION("LCD Lowlevel Control Abstraction"); |