xref: /openbmc/u-boot/drivers/video/anx9804.c (revision 78506c2f)
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 #define BIT(x) (1 << (x))
18 
19 /* Registers at i2c address 0x38 */
20 
21 #define ANX9804_HDCP_CONTROL_0_REG				0x01
22 
23 #define ANX9804_SYS_CTRL2_REG					0x81
24 #define ANX9804_SYS_CTRL2_CHA_STA				0x04
25 
26 #define ANX9804_SYS_CTRL3_REG					0x82
27 #define ANX9804_SYS_CTRL3_VALID_CTRL				BIT(0)
28 #define ANX9804_SYS_CTRL3_F_VALID				BIT(1)
29 #define ANX9804_SYS_CTRL3_HPD_CTRL				BIT(4)
30 #define ANX9804_SYS_CTRL3_F_HPD					BIT(5)
31 
32 #define ANX9804_LINK_BW_SET_REG					0xa0
33 #define ANX9804_LANE_COUNT_SET_REG				0xa1
34 #define ANX9804_TRAINING_PTN_SET_REG				0xa2
35 #define ANX9804_TRAINING_LANE0_SET_REG				0xa3
36 #define ANX9804_TRAINING_LANE1_SET_REG				0xa4
37 #define ANX9804_TRAINING_LANE2_SET_REG				0xa5
38 #define ANX9804_TRAINING_LANE3_SET_REG				0xa6
39 
40 #define ANX9804_LINK_TRAINING_CTRL_REG				0xa8
41 #define ANX9804_LINK_TRAINING_CTRL_EN				BIT(0)
42 
43 #define ANX9804_LINK_DEBUG_REG					0xb8
44 #define ANX9804_PLL_CTRL_REG					0xc7
45 #define ANX9804_ANALOG_POWER_DOWN_REG				0xc8
46 
47 /* Registers at i2c address 0x39 */
48 
49 #define ANX9804_DEV_IDH_REG					0x03
50 
51 #define ANX9804_POWERD_CTRL_REG					0x05
52 #define ANX9804_POWERD_AUDIO					BIT(4)
53 
54 #define ANX9804_RST_CTRL_REG					0x06
55 
56 #define ANX9804_RST_CTRL2_REG					0x07
57 #define ANX9804_RST_CTRL2_AUX					BIT(2)
58 #define ANX9804_RST_CTRL2_AC_MODE				BIT(6)
59 
60 #define ANX9804_VID_CTRL1_REG					0x08
61 #define ANX9804_VID_CTRL1_VID_EN				BIT(7)
62 #define ANX9804_VID_CTRL1_EDGE					BIT(0)
63 
64 #define ANX9804_VID_CTRL2_REG					0x09
65 #define ANX9804_ANALOG_DEBUG_REG1				0xdc
66 #define ANX9804_ANALOG_DEBUG_REG3				0xde
67 #define ANX9804_PLL_FILTER_CTRL1				0xdf
68 #define ANX9804_PLL_FILTER_CTRL3				0xe1
69 #define ANX9804_PLL_FILTER_CTRL					0xe2
70 #define ANX9804_PLL_CTRL3					0xe6
71 
72 /**
73  * anx9804_init() - Init anx9804 parallel lcd to edp bridge chip
74  *
75  * This function will init an anx9804 parallel lcd to dp bridge chip
76  * using the passed in parameters.
77  *
78  * @i2c_bus:	Number of the i2c bus to which the anx9804 is connected.
79  * @lanes:	Number of displayport lanes to use
80  * @data_rate:	Register value for the bandwidth reg 0x06: 1.62G, 0x0a: 2.7G
81  * @bpp:	Bits per pixel, must be 18 or 24
82  */
83 void anx9804_init(unsigned int i2c_bus, u8 lanes, u8 data_rate, int bpp)
84 {
85 	unsigned int orig_i2c_bus = i2c_get_bus_num();
86 	u8 c, colordepth;
87 	int i;
88 
89 	i2c_set_bus_num(i2c_bus);
90 
91 	if (bpp == 18)
92 		colordepth = 0x00; /* 6 bit */
93 	else
94 		colordepth = 0x10; /* 8 bit */
95 
96 	/* Reset */
97 	i2c_reg_write(0x39, ANX9804_RST_CTRL_REG, 1);
98 	mdelay(100);
99 	i2c_reg_write(0x39, ANX9804_RST_CTRL_REG, 0);
100 
101 	/* Write 0 to the powerdown reg (powerup everything) */
102 	i2c_reg_write(0x39, ANX9804_POWERD_CTRL_REG, 0);
103 
104 	c = i2c_reg_read(0x39, ANX9804_DEV_IDH_REG);
105 	if (c != 0x98) {
106 		printf("Error anx9804 chipid mismatch\n");
107 		i2c_set_bus_num(orig_i2c_bus);
108 		return;
109 	}
110 
111 	for (i = 0; i < 100; i++) {
112 		c = i2c_reg_read(0x38, ANX9804_SYS_CTRL2_REG);
113 		i2c_reg_write(0x38, ANX9804_SYS_CTRL2_REG, c);
114 		c = i2c_reg_read(0x38, ANX9804_SYS_CTRL2_REG);
115 		if ((c & ANX9804_SYS_CTRL2_CHA_STA) == 0)
116 			break;
117 
118 		mdelay(5);
119 	}
120 	if (i == 100)
121 		printf("Error anx9804 clock is not stable\n");
122 
123 	i2c_reg_write(0x39, ANX9804_VID_CTRL2_REG, colordepth);
124 
125 	/* Set a bunch of analog related register values */
126 	i2c_reg_write(0x38, ANX9804_PLL_CTRL_REG, 0x07);
127 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL3, 0x19);
128 	i2c_reg_write(0x39, ANX9804_PLL_CTRL3, 0xd9);
129 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG, ANX9804_RST_CTRL2_AC_MODE);
130 	i2c_reg_write(0x39, ANX9804_ANALOG_DEBUG_REG1, 0xf0);
131 	i2c_reg_write(0x39, ANX9804_ANALOG_DEBUG_REG3, 0x99);
132 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL1, 0x7b);
133 	i2c_reg_write(0x38, ANX9804_LINK_DEBUG_REG, 0x30);
134 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL, 0x06);
135 
136 	/* Force HPD */
137 	i2c_reg_write(0x38, ANX9804_SYS_CTRL3_REG,
138 		      ANX9804_SYS_CTRL3_F_HPD | ANX9804_SYS_CTRL3_HPD_CTRL);
139 
140 	/* Power up and configure lanes */
141 	i2c_reg_write(0x38, ANX9804_ANALOG_POWER_DOWN_REG, 0x00);
142 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE0_SET_REG, 0x00);
143 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE1_SET_REG, 0x00);
144 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE2_SET_REG, 0x00);
145 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE3_SET_REG, 0x00);
146 
147 	/* Reset AUX CH */
148 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG,
149 		      ANX9804_RST_CTRL2_AC_MODE | ANX9804_RST_CTRL2_AUX);
150 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG,
151 		      ANX9804_RST_CTRL2_AC_MODE);
152 
153 	/* Powerdown audio and some other unused bits */
154 	i2c_reg_write(0x39, ANX9804_POWERD_CTRL_REG, ANX9804_POWERD_AUDIO);
155 	i2c_reg_write(0x38, ANX9804_HDCP_CONTROL_0_REG, 0x00);
156 	i2c_reg_write(0x38, 0xa7, 0x00);
157 
158 	/* Set data-rate / lanes */
159 	i2c_reg_write(0x38, ANX9804_LINK_BW_SET_REG, data_rate);
160 	i2c_reg_write(0x38, ANX9804_LANE_COUNT_SET_REG, lanes);
161 
162 	/* Link training */
163 	i2c_reg_write(0x38, ANX9804_LINK_TRAINING_CTRL_REG,
164 		      ANX9804_LINK_TRAINING_CTRL_EN);
165 	mdelay(5);
166 	for (i = 0; i < 100; i++) {
167 		c = i2c_reg_read(0x38, ANX9804_LINK_TRAINING_CTRL_REG);
168 		if ((c & 0x01) == 0)
169 			break;
170 
171 		mdelay(5);
172 	}
173 	if(i == 100) {
174 		printf("Error anx9804 link training timeout\n");
175 		i2c_set_bus_num(orig_i2c_bus);
176 		return;
177 	}
178 
179 	/* Enable */
180 	i2c_reg_write(0x39, ANX9804_VID_CTRL1_REG,
181 		      ANX9804_VID_CTRL1_VID_EN | ANX9804_VID_CTRL1_EDGE);
182 	/* Force stream valid */
183 	i2c_reg_write(0x38, ANX9804_SYS_CTRL3_REG,
184 		      ANX9804_SYS_CTRL3_F_HPD | ANX9804_SYS_CTRL3_HPD_CTRL |
185 		      ANX9804_SYS_CTRL3_F_VALID | ANX9804_SYS_CTRL3_VALID_CTRL);
186 
187 	i2c_set_bus_num(orig_i2c_bus);
188 }
189