^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Backlight Lowlevel Control Abstraction
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2003,2004 Hewlett-Packard Company
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/backlight.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/notifier.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/ctype.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/fb.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #ifdef CONFIG_PMAC_BACKLIGHT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) #include <asm/backlight.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) * DOC: overview
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) * The backlight core supports implementing backlight drivers.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * A backlight driver registers a driver using
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) * devm_backlight_device_register(). The properties of the backlight
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) * driver such as type and max_brightness must be specified.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) * When the core detect changes in for example brightness or power state
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) * the update_status() operation is called. The backlight driver shall
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) * implement this operation and use it to adjust backlight.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * Several sysfs attributes are provided by the backlight core::
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) * - brightness R/W, set the requested brightness level
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) * - actual_brightness RO, the brightness level used by the HW
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) * - max_brightness RO, the maximum brightness level supported
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) * See Documentation/ABI/stable/sysfs-class-backlight for the full list.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) * The backlight can be adjusted using the sysfs interface, and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * the backlight driver may also support adjusting backlight using
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) * a hot-key or some other platform or firmware specific way.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) * The driver must implement the get_brightness() operation if
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) * the HW do not support all the levels that can be specified in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) * brightness, thus providing user-space access to the actual level
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) * via the actual_brightness attribute.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) * When the backlight changes this is reported to user-space using
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) * an uevent connected to the actual_brightness attribute.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) * When brightness is set by platform specific means, for example
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) * a hot-key to adjust backlight, the driver must notify the backlight
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) * core that brightness has changed using backlight_force_update().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) * The backlight driver core receives notifications from fbdev and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) * if the event is FB_EVENT_BLANK and if the value of blank, from the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) * FBIOBLANK ioctrl, results in a change in the backlight state the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) * update_status() operation is called.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) static struct list_head backlight_dev_list;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) static struct mutex backlight_dev_list_mutex;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) static struct blocking_notifier_head backlight_notifier;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) static const char *const backlight_types[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) [BACKLIGHT_RAW] = "raw",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) [BACKLIGHT_PLATFORM] = "platform",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) [BACKLIGHT_FIRMWARE] = "firmware",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) static const char *const backlight_scale_types[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) [BACKLIGHT_SCALE_UNKNOWN] = "unknown",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) [BACKLIGHT_SCALE_LINEAR] = "linear",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) [BACKLIGHT_SCALE_NON_LINEAR] = "non-linear",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) #if defined(CONFIG_FB) || (defined(CONFIG_FB_MODULE) && \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) defined(CONFIG_BACKLIGHT_CLASS_DEVICE_MODULE))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) * fb_notifier_callback
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) * This callback gets called when something important happens inside a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) * framebuffer driver. The backlight core only cares about FB_BLANK_UNBLANK
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) * which is reported to the driver using backlight_update_status()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) * as a state change.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) * There may be several fbdev's connected to the backlight device,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) * in which case they are kept track of. A state change is only reported
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) * if there is a change in backlight for the specified fbdev.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) static int fb_notifier_callback(struct notifier_block *self,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) unsigned long event, void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) struct backlight_device *bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) struct fb_event *evdata = data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) int node = evdata->info->node;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) int fb_blank = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) /* If we aren't interested in this event, skip it immediately ... */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) if (event != FB_EVENT_BLANK)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) bd = container_of(self, struct backlight_device, fb_notif);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) mutex_lock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) if (!bd->ops)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) if (bd->ops->check_fb && !bd->ops->check_fb(bd, evdata->info))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) goto out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) fb_blank = *(int *)evdata->data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) if (fb_blank == FB_BLANK_UNBLANK && !bd->fb_bl_on[node]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) bd->fb_bl_on[node] = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) if (!bd->use_count++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) bd->props.state &= ~BL_CORE_FBBLANK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) bd->props.fb_blank = FB_BLANK_UNBLANK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122) backlight_update_status(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) } else if (fb_blank != FB_BLANK_UNBLANK && bd->fb_bl_on[node]) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) bd->fb_bl_on[node] = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) if (!(--bd->use_count)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) bd->props.state |= BL_CORE_FBBLANK;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) bd->props.fb_blank = fb_blank;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) backlight_update_status(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) out:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) mutex_unlock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) static int backlight_register_fb(struct backlight_device *bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) memset(&bd->fb_notif, 0, sizeof(bd->fb_notif));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) bd->fb_notif.notifier_call = fb_notifier_callback;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) return fb_register_client(&bd->fb_notif);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) static void backlight_unregister_fb(struct backlight_device *bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) fb_unregister_client(&bd->fb_notif);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) #else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) static inline int backlight_register_fb(struct backlight_device *bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) static inline void backlight_unregister_fb(struct backlight_device *bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) #endif /* CONFIG_FB */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) static void backlight_generate_event(struct backlight_device *bd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) enum backlight_update_reason reason)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) char *envp[2];
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165) switch (reason) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) case BACKLIGHT_UPDATE_SYSFS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167) envp[0] = "SOURCE=sysfs";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) case BACKLIGHT_UPDATE_HOTKEY:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) envp[0] = "SOURCE=hotkey";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) default:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) envp[0] = "SOURCE=unknown";
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) envp[1] = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) kobject_uevent_env(&bd->dev.kobj, KOBJ_CHANGE, envp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) sysfs_notify(&bd->dev.kobj, NULL, "actual_brightness");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) static ssize_t bl_power_show(struct device *dev, struct device_attribute *attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) return sprintf(buf, "%d\n", bd->props.power);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189) static ssize_t bl_power_store(struct device *dev, struct device_attribute *attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) const char *buf, size_t count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) int rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194) unsigned long power, old_power;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) rc = kstrtoul(buf, 0, &power);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197) if (rc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) rc = -ENXIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) mutex_lock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 202) if (bd->ops) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 203) pr_debug("set power to %lu\n", power);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 204) if (bd->props.power != power) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 205) old_power = bd->props.power;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 206) bd->props.power = power;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 207) rc = backlight_update_status(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 208) if (rc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 209) bd->props.power = old_power;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 210) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 211) rc = count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 212) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 213) rc = count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 214) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 215) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 216) mutex_unlock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 217)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 218) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 219) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 220) static DEVICE_ATTR_RW(bl_power);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 221)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 222) static ssize_t brightness_show(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 223) struct device_attribute *attr, char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 224) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 225) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 226)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 227) return sprintf(buf, "%d\n", bd->props.brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 228) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 229)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 230) int backlight_device_set_brightness(struct backlight_device *bd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 231) unsigned long brightness)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 232) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 233) int rc = -ENXIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 234)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 235) mutex_lock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 236) if (bd->ops) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 237) if (brightness > bd->props.max_brightness)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 238) rc = -EINVAL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 239) else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 240) pr_debug("set brightness to %lu\n", brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 241) bd->props.brightness = brightness;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 242) rc = backlight_update_status(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 243) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 244) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 245) mutex_unlock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 246)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 247) backlight_generate_event(bd, BACKLIGHT_UPDATE_SYSFS);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 248)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 249) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 250) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 251) EXPORT_SYMBOL(backlight_device_set_brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 252)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 253) static ssize_t brightness_store(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 254) struct device_attribute *attr, const char *buf, size_t count)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 255) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 256) int rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 257) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 258) unsigned long brightness;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 259)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 260) rc = kstrtoul(buf, 0, &brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 261) if (rc)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 262) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 263)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 264) rc = backlight_device_set_brightness(bd, brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 265)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 266) return rc ? rc : count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 267) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 268) static DEVICE_ATTR_RW(brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 269)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 270) static ssize_t type_show(struct device *dev, struct device_attribute *attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 271) char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 272) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 273) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 274)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 275) return sprintf(buf, "%s\n", backlight_types[bd->props.type]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 276) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 277) static DEVICE_ATTR_RO(type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 278)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 279) static ssize_t max_brightness_show(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 280) struct device_attribute *attr, char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 281) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 282) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 283)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 284) return sprintf(buf, "%d\n", bd->props.max_brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 285) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 286) static DEVICE_ATTR_RO(max_brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 287)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 288) static ssize_t actual_brightness_show(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 289) struct device_attribute *attr, char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 290) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 291) int rc = -ENXIO;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 292) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 293)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 294) mutex_lock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 295) if (bd->ops && bd->ops->get_brightness)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 296) rc = sprintf(buf, "%d\n", bd->ops->get_brightness(bd));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 297) else
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 298) rc = sprintf(buf, "%d\n", bd->props.brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 299) mutex_unlock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 300)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 301) return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 302) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 303) static DEVICE_ATTR_RO(actual_brightness);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 304)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 305) static ssize_t scale_show(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 306) struct device_attribute *attr, char *buf)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 307) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 308) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 309)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 310) if (WARN_ON(bd->props.scale > BACKLIGHT_SCALE_NON_LINEAR))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 311) return sprintf(buf, "unknown\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 312)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 313) return sprintf(buf, "%s\n", backlight_scale_types[bd->props.scale]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 314) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 315) static DEVICE_ATTR_RO(scale);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 316)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 317) static struct class *backlight_class;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 318)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 319) #ifdef CONFIG_PM_SLEEP
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 320) static int backlight_suspend(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 321) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 322) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 323)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 324) mutex_lock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 325) if (bd->ops && bd->ops->options & BL_CORE_SUSPENDRESUME) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 326) bd->props.state |= BL_CORE_SUSPENDED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 327) backlight_update_status(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 328) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 329) mutex_unlock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 330)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 331) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 332) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 333)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 334) static int backlight_resume(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 335) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 336) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 337)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 338) mutex_lock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 339) if (bd->ops && bd->ops->options & BL_CORE_SUSPENDRESUME) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 340) bd->props.state &= ~BL_CORE_SUSPENDED;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 341) backlight_update_status(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 342) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 343) mutex_unlock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 344)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 345) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 346) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 347) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 348)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 349) static SIMPLE_DEV_PM_OPS(backlight_class_dev_pm_ops, backlight_suspend,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 350) backlight_resume);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 351)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 352) static void bl_device_release(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 353) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 354) struct backlight_device *bd = to_backlight_device(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 355) kfree(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 356) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 357)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 358) static struct attribute *bl_device_attrs[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 359) &dev_attr_bl_power.attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 360) &dev_attr_brightness.attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 361) &dev_attr_actual_brightness.attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 362) &dev_attr_max_brightness.attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 363) &dev_attr_scale.attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 364) &dev_attr_type.attr,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 365) NULL,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 366) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 367) ATTRIBUTE_GROUPS(bl_device);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 368)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 369) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 370) * backlight_force_update - tell the backlight subsystem that hardware state
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 371) * has changed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 372) * @bd: the backlight device to update
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 373) * @reason: reason for update
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 374) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 375) * Updates the internal state of the backlight in response to a hardware event,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 376) * and generates an uevent to notify userspace. A backlight driver shall call
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 377) * backlight_force_update() when the backlight is changed using, for example,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 378) * a hot-key. The updated brightness is read using get_brightness() and the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 379) * brightness value is reported using an uevent.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 380) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 381) void backlight_force_update(struct backlight_device *bd,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 382) enum backlight_update_reason reason)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 383) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 384) mutex_lock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 385) if (bd->ops && bd->ops->get_brightness)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 386) bd->props.brightness = bd->ops->get_brightness(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 387) mutex_unlock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 388) backlight_generate_event(bd, reason);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 389) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 390) EXPORT_SYMBOL(backlight_force_update);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 391)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 392) /* deprecated - use devm_backlight_device_register() */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 393) struct backlight_device *backlight_device_register(const char *name,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 394) struct device *parent, void *devdata, const struct backlight_ops *ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 395) const struct backlight_properties *props)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 396) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 397) struct backlight_device *new_bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 398) int rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 399)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 400) pr_debug("backlight_device_register: name=%s\n", name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 401)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 402) new_bd = kzalloc(sizeof(struct backlight_device), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 403) if (!new_bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 404) return ERR_PTR(-ENOMEM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 405)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 406) mutex_init(&new_bd->update_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 407) mutex_init(&new_bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 408)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 409) new_bd->dev.class = backlight_class;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 410) new_bd->dev.parent = parent;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 411) new_bd->dev.release = bl_device_release;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 412) dev_set_name(&new_bd->dev, "%s", name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 413) dev_set_drvdata(&new_bd->dev, devdata);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 414)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 415) /* Set default properties */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 416) if (props) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 417) memcpy(&new_bd->props, props,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 418) sizeof(struct backlight_properties));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 419) if (props->type <= 0 || props->type >= BACKLIGHT_TYPE_MAX) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 420) WARN(1, "%s: invalid backlight type", name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 421) new_bd->props.type = BACKLIGHT_RAW;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 422) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 423) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 424) new_bd->props.type = BACKLIGHT_RAW;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 425) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 426)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 427) rc = device_register(&new_bd->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 428) if (rc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 429) put_device(&new_bd->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 430) return ERR_PTR(rc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 431) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 432)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 433) rc = backlight_register_fb(new_bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 434) if (rc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 435) device_unregister(&new_bd->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 436) return ERR_PTR(rc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 437) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 438)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 439) new_bd->ops = ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 440)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 441) #ifdef CONFIG_PMAC_BACKLIGHT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 442) mutex_lock(&pmac_backlight_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 443) if (!pmac_backlight)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 444) pmac_backlight = new_bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 445) mutex_unlock(&pmac_backlight_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 446) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 447)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 448) mutex_lock(&backlight_dev_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 449) list_add(&new_bd->entry, &backlight_dev_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 450) mutex_unlock(&backlight_dev_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 451)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 452) blocking_notifier_call_chain(&backlight_notifier,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 453) BACKLIGHT_REGISTERED, new_bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 454)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 455) return new_bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 456) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 457) EXPORT_SYMBOL(backlight_device_register);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 458)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 459) /** backlight_device_get_by_type - find first backlight device of a type
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 460) * @type: the type of backlight device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 461) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 462) * Look up the first backlight device of the specified type
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 463) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 464) * RETURNS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 465) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 466) * Pointer to backlight device if any was found. Otherwise NULL.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 467) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 468) struct backlight_device *backlight_device_get_by_type(enum backlight_type type)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 469) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 470) bool found = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 471) struct backlight_device *bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 472)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 473) mutex_lock(&backlight_dev_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 474) list_for_each_entry(bd, &backlight_dev_list, entry) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 475) if (bd->props.type == type) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 476) found = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 477) break;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 478) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 479) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 480) mutex_unlock(&backlight_dev_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 481)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 482) return found ? bd : NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 483) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 484) EXPORT_SYMBOL(backlight_device_get_by_type);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 485)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 486) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 487) * backlight_device_get_by_name - Get backlight device by name
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 488) * @name: Device name
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 489) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 490) * This function looks up a backlight device by its name. It obtains a reference
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 491) * on the backlight device and it is the caller's responsibility to drop the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 492) * reference by calling backlight_put().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 493) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 494) * Returns:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 495) * A pointer to the backlight device if found, otherwise NULL.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 496) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 497) struct backlight_device *backlight_device_get_by_name(const char *name)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 498) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 499) struct device *dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 500)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 501) dev = class_find_device_by_name(backlight_class, name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 502)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 503) return dev ? to_backlight_device(dev) : NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 504) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 505) EXPORT_SYMBOL(backlight_device_get_by_name);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 506)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 507) /* deprecated - use devm_backlight_device_unregister() */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 508) void backlight_device_unregister(struct backlight_device *bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 509) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 510) if (!bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 511) return;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 512)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 513) mutex_lock(&backlight_dev_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 514) list_del(&bd->entry);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 515) mutex_unlock(&backlight_dev_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 516)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 517) #ifdef CONFIG_PMAC_BACKLIGHT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 518) mutex_lock(&pmac_backlight_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 519) if (pmac_backlight == bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 520) pmac_backlight = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 521) mutex_unlock(&pmac_backlight_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 522) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 523)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 524) blocking_notifier_call_chain(&backlight_notifier,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 525) BACKLIGHT_UNREGISTERED, bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 526)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 527) mutex_lock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 528) bd->ops = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 529) mutex_unlock(&bd->ops_lock);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 530)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 531) backlight_unregister_fb(bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 532) device_unregister(&bd->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 533) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 534) EXPORT_SYMBOL(backlight_device_unregister);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 535)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 536) static void devm_backlight_device_release(struct device *dev, void *res)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 537) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 538) struct backlight_device *backlight = *(struct backlight_device **)res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 539)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 540) backlight_device_unregister(backlight);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 541) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 542)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 543) static int devm_backlight_device_match(struct device *dev, void *res,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 544) void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 545) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 546) struct backlight_device **r = res;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 547)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 548) return *r == data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 549) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 550)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 551) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 552) * backlight_register_notifier - get notified of backlight (un)registration
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 553) * @nb: notifier block with the notifier to call on backlight (un)registration
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 554) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 555) * Register a notifier to get notified when backlight devices get registered
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 556) * or unregistered.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 557) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 558) * RETURNS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 559) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 560) * 0 on success, otherwise a negative error code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 561) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 562) int backlight_register_notifier(struct notifier_block *nb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 563) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 564) return blocking_notifier_chain_register(&backlight_notifier, nb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 565) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 566) EXPORT_SYMBOL(backlight_register_notifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 567)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 568) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 569) * backlight_unregister_notifier - unregister a backlight notifier
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 570) * @nb: notifier block to unregister
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 571) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 572) * Register a notifier to get notified when backlight devices get registered
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 573) * or unregistered.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 574) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 575) * RETURNS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 576) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 577) * 0 on success, otherwise a negative error code
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 578) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 579) int backlight_unregister_notifier(struct notifier_block *nb)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 580) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 581) return blocking_notifier_chain_unregister(&backlight_notifier, nb);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 582) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 583) EXPORT_SYMBOL(backlight_unregister_notifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 584)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 585) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 586) * devm_backlight_device_register - register a new backlight device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 587) * @dev: the device to register
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 588) * @name: the name of the device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 589) * @parent: a pointer to the parent device (often the same as @dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 590) * @devdata: an optional pointer to be stored for private driver use
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 591) * @ops: the backlight operations structure
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 592) * @props: the backlight properties
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 593) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 594) * Creates and registers new backlight device. When a backlight device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 595) * is registered the configuration must be specified in the @props
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 596) * parameter. See description of &backlight_properties.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 597) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 598) * RETURNS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 599) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 600) * struct backlight on success, or an ERR_PTR on error
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 601) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 602) struct backlight_device *devm_backlight_device_register(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 603) const char *name, struct device *parent, void *devdata,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 604) const struct backlight_ops *ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 605) const struct backlight_properties *props)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 606) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 607) struct backlight_device **ptr, *backlight;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 608)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 609) ptr = devres_alloc(devm_backlight_device_release, sizeof(*ptr),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 610) GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 611) if (!ptr)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 612) return ERR_PTR(-ENOMEM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 613)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 614) backlight = backlight_device_register(name, parent, devdata, ops,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 615) props);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 616) if (!IS_ERR(backlight)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 617) *ptr = backlight;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 618) devres_add(dev, ptr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 619) } else {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 620) devres_free(ptr);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 621) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 622)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 623) return backlight;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 624) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 625) EXPORT_SYMBOL(devm_backlight_device_register);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 626)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 627) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 628) * devm_backlight_device_unregister - unregister backlight device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 629) * @dev: the device to unregister
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 630) * @bd: the backlight device to unregister
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 631) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 632) * Deallocates a backlight allocated with devm_backlight_device_register().
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 633) * Normally this function will not need to be called and the resource management
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 634) * code will ensure that the resources are freed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 635) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 636) void devm_backlight_device_unregister(struct device *dev,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 637) struct backlight_device *bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 638) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 639) int rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 640)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 641) rc = devres_release(dev, devm_backlight_device_release,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 642) devm_backlight_device_match, bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 643) WARN_ON(rc);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 644) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 645) EXPORT_SYMBOL(devm_backlight_device_unregister);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 646)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 647) #ifdef CONFIG_OF
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 648) static int of_parent_match(struct device *dev, const void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 649) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 650) return dev->parent && dev->parent->of_node == data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 651) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 652)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 653) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 654) * of_find_backlight_by_node() - find backlight device by device-tree node
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 655) * @node: device-tree node of the backlight device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 656) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 657) * Returns a pointer to the backlight device corresponding to the given DT
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 658) * node or NULL if no such backlight device exists or if the device hasn't
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 659) * been probed yet.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 660) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 661) * This function obtains a reference on the backlight device and it is the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 662) * caller's responsibility to drop the reference by calling put_device() on
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 663) * the backlight device's .dev field.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 664) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 665) struct backlight_device *of_find_backlight_by_node(struct device_node *node)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 666) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 667) struct device *dev;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 668)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 669) dev = class_find_device(backlight_class, NULL, node, of_parent_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 670)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 671) return dev ? to_backlight_device(dev) : NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 672) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 673) EXPORT_SYMBOL(of_find_backlight_by_node);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 674) #endif
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 675)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 676) static struct backlight_device *of_find_backlight(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 677) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 678) struct backlight_device *bd = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 679) struct device_node *np;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 680)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 681) if (!dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 682) return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 683)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 684) if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 685) np = of_parse_phandle(dev->of_node, "backlight", 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 686) if (np) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 687) bd = of_find_backlight_by_node(np);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 688) of_node_put(np);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 689) if (!bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 690) return ERR_PTR(-EPROBE_DEFER);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 691) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 692) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 693)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 694) return bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 695) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 696)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 697) static void devm_backlight_release(void *data)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 698) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 699) struct backlight_device *bd = data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 700)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 701) if (bd)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 702) put_device(&bd->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 703) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 704)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 705) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 706) * devm_of_find_backlight - find backlight for a device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 707) * @dev: the device
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 708) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 709) * This function looks for a property named 'backlight' on the DT node
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 710) * connected to @dev and looks up the backlight device. The lookup is
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 711) * device managed so the reference to the backlight device is automatically
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 712) * dropped on driver detach.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 713) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 714) * RETURNS:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 715) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 716) * A pointer to the backlight device if found.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 717) * Error pointer -EPROBE_DEFER if the DT property is set, but no backlight
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 718) * device is found. NULL if there's no backlight property.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 719) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 720) struct backlight_device *devm_of_find_backlight(struct device *dev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 721) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 722) struct backlight_device *bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 723) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 724)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 725) bd = of_find_backlight(dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 726) if (IS_ERR_OR_NULL(bd))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 727) return bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 728) ret = devm_add_action(dev, devm_backlight_release, bd);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 729) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 730) put_device(&bd->dev);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 731) return ERR_PTR(ret);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 732) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 733) return bd;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 734) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 735) EXPORT_SYMBOL(devm_of_find_backlight);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 736)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 737) static void __exit backlight_class_exit(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 738) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 739) class_destroy(backlight_class);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 740) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 741)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 742) static int __init backlight_class_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 743) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 744) backlight_class = class_create(THIS_MODULE, "backlight");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 745) if (IS_ERR(backlight_class)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 746) pr_warn("Unable to create backlight class; errno = %ld\n",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 747) PTR_ERR(backlight_class));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 748) return PTR_ERR(backlight_class);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 749) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 750)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 751) backlight_class->dev_groups = bl_device_groups;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 752) backlight_class->pm = &backlight_class_dev_pm_ops;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 753) INIT_LIST_HEAD(&backlight_dev_list);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 754) mutex_init(&backlight_dev_list_mutex);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 755) BLOCKING_INIT_NOTIFIER_HEAD(&backlight_notifier);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 756)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 757) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 758) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 759)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 760) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 761) * if this is compiled into the kernel, we need to ensure that the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 762) * class is registered before users of the class try to register lcd's
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 763) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 764) postcore_initcall(backlight_class_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 765) module_exit(backlight_class_exit);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 766)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 767) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 768) MODULE_AUTHOR("Jamey Hicks <jamey.hicks@hp.com>, Andrew Zabolotny <zap@homelink.ru>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 769) MODULE_DESCRIPTION("Backlight Lowlevel Control Abstraction");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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