1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Based on drivers/video/omap/lcd_inn1510.c
4  *
5  * LCD panel support for the Amstrad E3 (Delta) videophone.
6  *
7  * Copyright (C) 2006 Jonathan McDowell <noodles@earth.li>
8  */
9 
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/io.h>
13 #include <linux/delay.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/lcd.h>
16 
17 #include <linux/soc/ti/omap1-io.h>
18 
19 #include "omapfb.h"
20 
21 #define AMS_DELTA_DEFAULT_CONTRAST	112
22 
23 #define AMS_DELTA_MAX_CONTRAST		0x00FF
24 #define AMS_DELTA_LCD_POWER		0x0100
25 
26 
27 /* LCD class device section */
28 
29 static int ams_delta_lcd;
30 static struct gpio_desc *gpiod_vblen;
31 static struct gpio_desc *gpiod_ndisp;
32 
ams_delta_lcd_set_power(struct lcd_device * dev,int power)33 static int ams_delta_lcd_set_power(struct lcd_device *dev, int power)
34 {
35 	if (power == FB_BLANK_UNBLANK) {
36 		if (!(ams_delta_lcd & AMS_DELTA_LCD_POWER)) {
37 			omap_writeb(ams_delta_lcd & AMS_DELTA_MAX_CONTRAST,
38 					OMAP_PWL_ENABLE);
39 			omap_writeb(1, OMAP_PWL_CLK_ENABLE);
40 			ams_delta_lcd |= AMS_DELTA_LCD_POWER;
41 		}
42 	} else {
43 		if (ams_delta_lcd & AMS_DELTA_LCD_POWER) {
44 			omap_writeb(0, OMAP_PWL_ENABLE);
45 			omap_writeb(0, OMAP_PWL_CLK_ENABLE);
46 			ams_delta_lcd &= ~AMS_DELTA_LCD_POWER;
47 		}
48 	}
49 	return 0;
50 }
51 
ams_delta_lcd_set_contrast(struct lcd_device * dev,int value)52 static int ams_delta_lcd_set_contrast(struct lcd_device *dev, int value)
53 {
54 	if ((value >= 0) && (value <= AMS_DELTA_MAX_CONTRAST)) {
55 		omap_writeb(value, OMAP_PWL_ENABLE);
56 		ams_delta_lcd &= ~AMS_DELTA_MAX_CONTRAST;
57 		ams_delta_lcd |= value;
58 	}
59 	return 0;
60 }
61 
62 #ifdef CONFIG_LCD_CLASS_DEVICE
ams_delta_lcd_get_power(struct lcd_device * dev)63 static int ams_delta_lcd_get_power(struct lcd_device *dev)
64 {
65 	if (ams_delta_lcd & AMS_DELTA_LCD_POWER)
66 		return FB_BLANK_UNBLANK;
67 	else
68 		return FB_BLANK_POWERDOWN;
69 }
70 
ams_delta_lcd_get_contrast(struct lcd_device * dev)71 static int ams_delta_lcd_get_contrast(struct lcd_device *dev)
72 {
73 	if (!(ams_delta_lcd & AMS_DELTA_LCD_POWER))
74 		return 0;
75 
76 	return ams_delta_lcd & AMS_DELTA_MAX_CONTRAST;
77 }
78 
79 static struct lcd_ops ams_delta_lcd_ops = {
80 	.get_power = ams_delta_lcd_get_power,
81 	.set_power = ams_delta_lcd_set_power,
82 	.get_contrast = ams_delta_lcd_get_contrast,
83 	.set_contrast = ams_delta_lcd_set_contrast,
84 };
85 #endif
86 
87 
88 /* omapfb panel section */
89 
ams_delta_panel_enable(struct lcd_panel * panel)90 static int ams_delta_panel_enable(struct lcd_panel *panel)
91 {
92 	gpiod_set_value(gpiod_ndisp, 1);
93 	gpiod_set_value(gpiod_vblen, 1);
94 	return 0;
95 }
96 
ams_delta_panel_disable(struct lcd_panel * panel)97 static void ams_delta_panel_disable(struct lcd_panel *panel)
98 {
99 	gpiod_set_value(gpiod_vblen, 0);
100 	gpiod_set_value(gpiod_ndisp, 0);
101 }
102 
103 static struct lcd_panel ams_delta_panel = {
104 	.name		= "ams-delta",
105 	.config		= 0,
106 
107 	.bpp		= 12,
108 	.data_lines	= 16,
109 	.x_res		= 480,
110 	.y_res		= 320,
111 	.pixel_clock	= 4687,
112 	.hsw		= 3,
113 	.hfp		= 1,
114 	.hbp		= 1,
115 	.vsw		= 1,
116 	.vfp		= 0,
117 	.vbp		= 0,
118 	.pcd		= 0,
119 	.acb		= 37,
120 
121 	.enable		= ams_delta_panel_enable,
122 	.disable	= ams_delta_panel_disable,
123 };
124 
125 
126 /* platform driver section */
127 
ams_delta_panel_probe(struct platform_device * pdev)128 static int ams_delta_panel_probe(struct platform_device *pdev)
129 {
130 	struct lcd_device *lcd_device = NULL;
131 
132 	gpiod_vblen = devm_gpiod_get(&pdev->dev, "vblen", GPIOD_OUT_LOW);
133 	if (IS_ERR(gpiod_vblen))
134 		return dev_err_probe(&pdev->dev, PTR_ERR(gpiod_vblen),
135 				     "VBLEN GPIO request failed\n");
136 
137 	gpiod_ndisp = devm_gpiod_get(&pdev->dev, "ndisp", GPIOD_OUT_LOW);
138 	if (IS_ERR(gpiod_ndisp))
139 		return dev_err_probe(&pdev->dev, PTR_ERR(gpiod_ndisp),
140 				     "NDISP GPIO request failed\n");
141 
142 #ifdef CONFIG_LCD_CLASS_DEVICE
143 	lcd_device = lcd_device_register("omapfb", &pdev->dev, NULL,
144 						&ams_delta_lcd_ops);
145 
146 	if (IS_ERR(lcd_device)) {
147 		int ret = PTR_ERR(lcd_device);
148 
149 		dev_err(&pdev->dev, "failed to register device\n");
150 		return ret;
151 	}
152 
153 	platform_set_drvdata(pdev, lcd_device);
154 	lcd_device->props.max_contrast = AMS_DELTA_MAX_CONTRAST;
155 #endif
156 
157 	ams_delta_lcd_set_contrast(lcd_device, AMS_DELTA_DEFAULT_CONTRAST);
158 	ams_delta_lcd_set_power(lcd_device, FB_BLANK_UNBLANK);
159 
160 	omapfb_register_panel(&ams_delta_panel);
161 	return 0;
162 }
163 
164 static struct platform_driver ams_delta_panel_driver = {
165 	.probe		= ams_delta_panel_probe,
166 	.driver		= {
167 		.name	= "lcd_ams_delta",
168 	},
169 };
170 
171 module_platform_driver(ams_delta_panel_driver);
172 
173 MODULE_AUTHOR("Jonathan McDowell <noodles@earth.li>");
174 MODULE_DESCRIPTION("LCD panel support for the Amstrad E3 (Delta) videophone");
175 MODULE_LICENSE("GPL");
176