xref: /openbmc/u-boot/drivers/video/anx9804.c (revision 5be93569)
1 /*
2  * (C) 2015 Hans de Goede <hdegoede@redhat.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 /*
8  * Support for the ANX9804 bridge chip, which can take pixel data coming
9  * from a parallel LCD interface and translate it on the flight into a DP
10  * interface for driving eDP TFT displays.
11  */
12 
13 #include <common.h>
14 #include <i2c.h>
15 #include "anx9804.h"
16 
17 /* Registers at i2c address 0x38 */
18 
19 #define ANX9804_HDCP_CONTROL_0_REG				0x01
20 
21 #define ANX9804_SYS_CTRL2_REG					0x81
22 #define ANX9804_SYS_CTRL2_CHA_STA				0x04
23 
24 #define ANX9804_SYS_CTRL3_REG					0x82
25 #define ANX9804_SYS_CTRL3_VALID_CTRL				BIT(0)
26 #define ANX9804_SYS_CTRL3_F_VALID				BIT(1)
27 #define ANX9804_SYS_CTRL3_HPD_CTRL				BIT(4)
28 #define ANX9804_SYS_CTRL3_F_HPD					BIT(5)
29 
30 #define ANX9804_LINK_BW_SET_REG					0xa0
31 #define ANX9804_LANE_COUNT_SET_REG				0xa1
32 #define ANX9804_TRAINING_PTN_SET_REG				0xa2
33 #define ANX9804_TRAINING_LANE0_SET_REG				0xa3
34 #define ANX9804_TRAINING_LANE1_SET_REG				0xa4
35 #define ANX9804_TRAINING_LANE2_SET_REG				0xa5
36 #define ANX9804_TRAINING_LANE3_SET_REG				0xa6
37 
38 #define ANX9804_LINK_TRAINING_CTRL_REG				0xa8
39 #define ANX9804_LINK_TRAINING_CTRL_EN				BIT(0)
40 
41 #define ANX9804_LINK_DEBUG_REG					0xb8
42 #define ANX9804_PLL_CTRL_REG					0xc7
43 #define ANX9804_ANALOG_POWER_DOWN_REG				0xc8
44 
45 /* Registers at i2c address 0x39 */
46 
47 #define ANX9804_DEV_IDH_REG					0x03
48 
49 #define ANX9804_POWERD_CTRL_REG					0x05
50 #define ANX9804_POWERD_AUDIO					BIT(4)
51 
52 #define ANX9804_RST_CTRL_REG					0x06
53 
54 #define ANX9804_RST_CTRL2_REG					0x07
55 #define ANX9804_RST_CTRL2_AUX					BIT(2)
56 #define ANX9804_RST_CTRL2_AC_MODE				BIT(6)
57 
58 #define ANX9804_VID_CTRL1_REG					0x08
59 #define ANX9804_VID_CTRL1_VID_EN				BIT(7)
60 #define ANX9804_VID_CTRL1_EDGE					BIT(0)
61 
62 #define ANX9804_VID_CTRL2_REG					0x09
63 #define ANX9804_ANALOG_DEBUG_REG1				0xdc
64 #define ANX9804_ANALOG_DEBUG_REG3				0xde
65 #define ANX9804_PLL_FILTER_CTRL1				0xdf
66 #define ANX9804_PLL_FILTER_CTRL3				0xe1
67 #define ANX9804_PLL_FILTER_CTRL					0xe2
68 #define ANX9804_PLL_CTRL3					0xe6
69 
70 /**
71  * anx9804_init() - Init anx9804 parallel lcd to edp bridge chip
72  *
73  * This function will init an anx9804 parallel lcd to dp bridge chip
74  * using the passed in parameters.
75  *
76  * @i2c_bus:	Number of the i2c bus to which the anx9804 is connected.
77  * @lanes:	Number of displayport lanes to use
78  * @data_rate:	Register value for the bandwidth reg 0x06: 1.62G, 0x0a: 2.7G
79  * @bpp:	Bits per pixel, must be 18 or 24
80  */
81 void anx9804_init(unsigned int i2c_bus, u8 lanes, u8 data_rate, int bpp)
82 {
83 	unsigned int orig_i2c_bus = i2c_get_bus_num();
84 	u8 c, colordepth;
85 	int i;
86 
87 	i2c_set_bus_num(i2c_bus);
88 
89 	if (bpp == 18)
90 		colordepth = 0x00; /* 6 bit */
91 	else
92 		colordepth = 0x10; /* 8 bit */
93 
94 	/* Reset */
95 	i2c_reg_write(0x39, ANX9804_RST_CTRL_REG, 1);
96 	mdelay(100);
97 	i2c_reg_write(0x39, ANX9804_RST_CTRL_REG, 0);
98 
99 	/* Write 0 to the powerdown reg (powerup everything) */
100 	i2c_reg_write(0x39, ANX9804_POWERD_CTRL_REG, 0);
101 
102 	c = i2c_reg_read(0x39, ANX9804_DEV_IDH_REG);
103 	if (c != 0x98) {
104 		printf("Error anx9804 chipid mismatch\n");
105 		i2c_set_bus_num(orig_i2c_bus);
106 		return;
107 	}
108 
109 	for (i = 0; i < 100; i++) {
110 		c = i2c_reg_read(0x38, ANX9804_SYS_CTRL2_REG);
111 		i2c_reg_write(0x38, ANX9804_SYS_CTRL2_REG, c);
112 		c = i2c_reg_read(0x38, ANX9804_SYS_CTRL2_REG);
113 		if ((c & ANX9804_SYS_CTRL2_CHA_STA) == 0)
114 			break;
115 
116 		mdelay(5);
117 	}
118 	if (i == 100)
119 		printf("Error anx9804 clock is not stable\n");
120 
121 	i2c_reg_write(0x39, ANX9804_VID_CTRL2_REG, colordepth);
122 
123 	/* Set a bunch of analog related register values */
124 	i2c_reg_write(0x38, ANX9804_PLL_CTRL_REG, 0x07);
125 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL3, 0x19);
126 	i2c_reg_write(0x39, ANX9804_PLL_CTRL3, 0xd9);
127 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG, ANX9804_RST_CTRL2_AC_MODE);
128 	i2c_reg_write(0x39, ANX9804_ANALOG_DEBUG_REG1, 0xf0);
129 	i2c_reg_write(0x39, ANX9804_ANALOG_DEBUG_REG3, 0x99);
130 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL1, 0x7b);
131 	i2c_reg_write(0x38, ANX9804_LINK_DEBUG_REG, 0x30);
132 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL, 0x06);
133 
134 	/* Force HPD */
135 	i2c_reg_write(0x38, ANX9804_SYS_CTRL3_REG,
136 		      ANX9804_SYS_CTRL3_F_HPD | ANX9804_SYS_CTRL3_HPD_CTRL);
137 
138 	/* Power up and configure lanes */
139 	i2c_reg_write(0x38, ANX9804_ANALOG_POWER_DOWN_REG, 0x00);
140 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE0_SET_REG, 0x00);
141 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE1_SET_REG, 0x00);
142 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE2_SET_REG, 0x00);
143 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE3_SET_REG, 0x00);
144 
145 	/* Reset AUX CH */
146 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG,
147 		      ANX9804_RST_CTRL2_AC_MODE | ANX9804_RST_CTRL2_AUX);
148 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG,
149 		      ANX9804_RST_CTRL2_AC_MODE);
150 
151 	/* Powerdown audio and some other unused bits */
152 	i2c_reg_write(0x39, ANX9804_POWERD_CTRL_REG, ANX9804_POWERD_AUDIO);
153 	i2c_reg_write(0x38, ANX9804_HDCP_CONTROL_0_REG, 0x00);
154 	i2c_reg_write(0x38, 0xa7, 0x00);
155 
156 	/* Set data-rate / lanes */
157 	i2c_reg_write(0x38, ANX9804_LINK_BW_SET_REG, data_rate);
158 	i2c_reg_write(0x38, ANX9804_LANE_COUNT_SET_REG, lanes);
159 
160 	/* Link training */
161 	i2c_reg_write(0x38, ANX9804_LINK_TRAINING_CTRL_REG,
162 		      ANX9804_LINK_TRAINING_CTRL_EN);
163 	mdelay(5);
164 	for (i = 0; i < 100; i++) {
165 		c = i2c_reg_read(0x38, ANX9804_LINK_TRAINING_CTRL_REG);
166 		if ((c & 0x01) == 0)
167 			break;
168 
169 		mdelay(5);
170 	}
171 	if(i == 100) {
172 		printf("Error anx9804 link training timeout\n");
173 		i2c_set_bus_num(orig_i2c_bus);
174 		return;
175 	}
176 
177 	/* Enable */
178 	i2c_reg_write(0x39, ANX9804_VID_CTRL1_REG,
179 		      ANX9804_VID_CTRL1_VID_EN | ANX9804_VID_CTRL1_EDGE);
180 	/* Force stream valid */
181 	i2c_reg_write(0x38, ANX9804_SYS_CTRL3_REG,
182 		      ANX9804_SYS_CTRL3_F_HPD | ANX9804_SYS_CTRL3_HPD_CTRL |
183 		      ANX9804_SYS_CTRL3_F_VALID | ANX9804_SYS_CTRL3_VALID_CTRL);
184 
185 	i2c_set_bus_num(orig_i2c_bus);
186 }
187