1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * iPAQ microcontroller backlight support
5*4882a593Smuzhiyun * Author : Linus Walleij <linus.walleij@linaro.org>
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <linux/backlight.h>
9*4882a593Smuzhiyun #include <linux/err.h>
10*4882a593Smuzhiyun #include <linux/fb.h>
11*4882a593Smuzhiyun #include <linux/init.h>
12*4882a593Smuzhiyun #include <linux/mfd/ipaq-micro.h>
13*4882a593Smuzhiyun #include <linux/module.h>
14*4882a593Smuzhiyun #include <linux/platform_device.h>
15*4882a593Smuzhiyun
micro_bl_update_status(struct backlight_device * bd)16*4882a593Smuzhiyun static int micro_bl_update_status(struct backlight_device *bd)
17*4882a593Smuzhiyun {
18*4882a593Smuzhiyun struct ipaq_micro *micro = dev_get_drvdata(&bd->dev);
19*4882a593Smuzhiyun int intensity = bd->props.brightness;
20*4882a593Smuzhiyun struct ipaq_micro_msg msg = {
21*4882a593Smuzhiyun .id = MSG_BACKLIGHT,
22*4882a593Smuzhiyun .tx_len = 3,
23*4882a593Smuzhiyun };
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun if (bd->props.power != FB_BLANK_UNBLANK)
26*4882a593Smuzhiyun intensity = 0;
27*4882a593Smuzhiyun if (bd->props.state & (BL_CORE_FBBLANK | BL_CORE_SUSPENDED))
28*4882a593Smuzhiyun intensity = 0;
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun /*
31*4882a593Smuzhiyun * Message format:
32*4882a593Smuzhiyun * Byte 0: backlight instance (usually 1)
33*4882a593Smuzhiyun * Byte 1: on/off
34*4882a593Smuzhiyun * Byte 2: intensity, 0-255
35*4882a593Smuzhiyun */
36*4882a593Smuzhiyun msg.tx_data[0] = 0x01;
37*4882a593Smuzhiyun msg.tx_data[1] = intensity > 0 ? 1 : 0;
38*4882a593Smuzhiyun msg.tx_data[2] = intensity;
39*4882a593Smuzhiyun return ipaq_micro_tx_msg_sync(micro, &msg);
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun static const struct backlight_ops micro_bl_ops = {
43*4882a593Smuzhiyun .options = BL_CORE_SUSPENDRESUME,
44*4882a593Smuzhiyun .update_status = micro_bl_update_status,
45*4882a593Smuzhiyun };
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun static const struct backlight_properties micro_bl_props = {
48*4882a593Smuzhiyun .type = BACKLIGHT_RAW,
49*4882a593Smuzhiyun .max_brightness = 255,
50*4882a593Smuzhiyun .power = FB_BLANK_UNBLANK,
51*4882a593Smuzhiyun .brightness = 64,
52*4882a593Smuzhiyun };
53*4882a593Smuzhiyun
micro_backlight_probe(struct platform_device * pdev)54*4882a593Smuzhiyun static int micro_backlight_probe(struct platform_device *pdev)
55*4882a593Smuzhiyun {
56*4882a593Smuzhiyun struct backlight_device *bd;
57*4882a593Smuzhiyun struct ipaq_micro *micro = dev_get_drvdata(pdev->dev.parent);
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun bd = devm_backlight_device_register(&pdev->dev, "ipaq-micro-backlight",
60*4882a593Smuzhiyun &pdev->dev, micro, µ_bl_ops,
61*4882a593Smuzhiyun µ_bl_props);
62*4882a593Smuzhiyun if (IS_ERR(bd))
63*4882a593Smuzhiyun return PTR_ERR(bd);
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun platform_set_drvdata(pdev, bd);
66*4882a593Smuzhiyun backlight_update_status(bd);
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun return 0;
69*4882a593Smuzhiyun }
70*4882a593Smuzhiyun
71*4882a593Smuzhiyun static struct platform_driver micro_backlight_device_driver = {
72*4882a593Smuzhiyun .driver = {
73*4882a593Smuzhiyun .name = "ipaq-micro-backlight",
74*4882a593Smuzhiyun },
75*4882a593Smuzhiyun .probe = micro_backlight_probe,
76*4882a593Smuzhiyun };
77*4882a593Smuzhiyun module_platform_driver(micro_backlight_device_driver);
78*4882a593Smuzhiyun
79*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
80*4882a593Smuzhiyun MODULE_DESCRIPTION("driver for iPAQ Atmel micro backlight");
81*4882a593Smuzhiyun MODULE_ALIAS("platform:ipaq-micro-backlight");
82