1// SPDX-License-Identifier: GPL-2.0+
 2/*
 3 * shmob_drm_backlight.c  --  SH Mobile DRM Backlight
 4 *
 5 * Copyright (C) 2012 Renesas Electronics Corporation
 6 *
 7 * Laurent Pinchart (laurent.pinchart@ideasonboard.com)
 8 */
 9
10#include <linux/backlight.h>
11
12#include "shmob_drm_backlight.h"
13#include "shmob_drm_crtc.h"
14#include "shmob_drm_drv.h"
15
16static int shmob_drm_backlight_update(struct backlight_device *bdev)
17{
18	struct shmob_drm_connector *scon = bl_get_data(bdev);
19	struct shmob_drm_device *sdev = scon->connector.dev->dev_private;
20	const struct shmob_drm_backlight_data *bdata = &sdev->pdata->backlight;
21	int brightness = backlight_get_brightness(bdev);
22
23	return bdata->set_brightness(brightness);
24}
25
26static int shmob_drm_backlight_get_brightness(struct backlight_device *bdev)
27{
28	struct shmob_drm_connector *scon = bl_get_data(bdev);
29	struct shmob_drm_device *sdev = scon->connector.dev->dev_private;
30	const struct shmob_drm_backlight_data *bdata = &sdev->pdata->backlight;
31
32	return bdata->get_brightness();
33}
34
35static const struct backlight_ops shmob_drm_backlight_ops = {
36	.options	= BL_CORE_SUSPENDRESUME,
37	.update_status	= shmob_drm_backlight_update,
38	.get_brightness	= shmob_drm_backlight_get_brightness,
39};
40
41void shmob_drm_backlight_dpms(struct shmob_drm_connector *scon, int mode)
42{
43	if (scon->backlight == NULL)
44		return;
45
46	scon->backlight->props.power = mode == DRM_MODE_DPMS_ON
47				     ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
48	backlight_update_status(scon->backlight);
49}
50
51int shmob_drm_backlight_init(struct shmob_drm_connector *scon)
52{
53	struct shmob_drm_device *sdev = scon->connector.dev->dev_private;
54	const struct shmob_drm_backlight_data *bdata = &sdev->pdata->backlight;
55	struct drm_connector *connector = &scon->connector;
56	struct drm_device *dev = connector->dev;
57	struct backlight_device *backlight;
58
59	if (!bdata->max_brightness)
60		return 0;
61
62	backlight = backlight_device_register(bdata->name, dev->dev, scon,
63					      &shmob_drm_backlight_ops, NULL);
64	if (IS_ERR(backlight)) {
65		dev_err(dev->dev, "unable to register backlight device: %ld\n",
66			PTR_ERR(backlight));
67		return PTR_ERR(backlight);
68	}
69
70	backlight->props.max_brightness = bdata->max_brightness;
71	backlight->props.brightness = bdata->max_brightness;
72	backlight->props.power = FB_BLANK_POWERDOWN;
73	backlight_update_status(backlight);
74
75	scon->backlight = backlight;
76	return 0;
77}
78
79void shmob_drm_backlight_exit(struct shmob_drm_connector *scon)
80{
81	backlight_device_unregister(scon->backlight);
82}