xref: /openbmc/u-boot/drivers/video/anx9804.c (revision cf0bcd7d)
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 "anx98xx-edp.h"
16 #include "anx9804.h"
17 
18 /**
19  * anx9804_init() - Init anx9804 parallel lcd to edp bridge chip
20  *
21  * This function will init an anx9804 parallel lcd to dp bridge chip
22  * using the passed in parameters.
23  *
24  * @i2c_bus:	Number of the i2c bus to which the anx9804 is connected.
25  * @lanes:	Number of displayport lanes to use
26  * @data_rate:	Register value for the bandwidth reg 0x06: 1.62G, 0x0a: 2.7G
27  * @bpp:	Bits per pixel, must be 18 or 24
28  */
29 void anx9804_init(unsigned int i2c_bus, u8 lanes, u8 data_rate, int bpp)
30 {
31 	unsigned int orig_i2c_bus = i2c_get_bus_num();
32 	u8 c, colordepth;
33 	int i;
34 
35 	i2c_set_bus_num(i2c_bus);
36 
37 	if (bpp == 18)
38 		colordepth = 0x00; /* 6 bit */
39 	else
40 		colordepth = 0x10; /* 8 bit */
41 
42 	/* Reset */
43 	i2c_reg_write(0x39, ANX9804_RST_CTRL_REG, 1);
44 	mdelay(100);
45 	i2c_reg_write(0x39, ANX9804_RST_CTRL_REG, 0);
46 
47 	/* Write 0 to the powerdown reg (powerup everything) */
48 	i2c_reg_write(0x39, ANX9804_POWERD_CTRL_REG, 0);
49 
50 	c = i2c_reg_read(0x39, ANX9804_DEV_IDH_REG);
51 	if (c != 0x98) {
52 		printf("Error anx9804 chipid mismatch\n");
53 		i2c_set_bus_num(orig_i2c_bus);
54 		return;
55 	}
56 
57 	for (i = 0; i < 100; i++) {
58 		c = i2c_reg_read(0x38, ANX9804_SYS_CTRL2_REG);
59 		i2c_reg_write(0x38, ANX9804_SYS_CTRL2_REG, c);
60 		c = i2c_reg_read(0x38, ANX9804_SYS_CTRL2_REG);
61 		if ((c & ANX9804_SYS_CTRL2_CHA_STA) == 0)
62 			break;
63 
64 		mdelay(5);
65 	}
66 	if (i == 100)
67 		printf("Error anx9804 clock is not stable\n");
68 
69 	i2c_reg_write(0x39, ANX9804_VID_CTRL2_REG, colordepth);
70 
71 	/* Set a bunch of analog related register values */
72 	i2c_reg_write(0x38, ANX9804_PLL_CTRL_REG, 0x07);
73 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL3, 0x19);
74 	i2c_reg_write(0x39, ANX9804_PLL_CTRL3, 0xd9);
75 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG, ANX9804_RST_CTRL2_AC_MODE);
76 	i2c_reg_write(0x39, ANX9804_ANALOG_DEBUG_REG1, 0xf0);
77 	i2c_reg_write(0x39, ANX9804_ANALOG_DEBUG_REG3, 0x99);
78 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL1, 0x7b);
79 	i2c_reg_write(0x38, ANX9804_LINK_DEBUG_REG, 0x30);
80 	i2c_reg_write(0x39, ANX9804_PLL_FILTER_CTRL, 0x06);
81 
82 	/* Force HPD */
83 	i2c_reg_write(0x38, ANX9804_SYS_CTRL3_REG,
84 		      ANX9804_SYS_CTRL3_F_HPD | ANX9804_SYS_CTRL3_HPD_CTRL);
85 
86 	/* Power up and configure lanes */
87 	i2c_reg_write(0x38, ANX9804_ANALOG_POWER_DOWN_REG, 0x00);
88 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE0_SET_REG, 0x00);
89 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE1_SET_REG, 0x00);
90 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE2_SET_REG, 0x00);
91 	i2c_reg_write(0x38, ANX9804_TRAINING_LANE3_SET_REG, 0x00);
92 
93 	/* Reset AUX CH */
94 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG,
95 		      ANX9804_RST_CTRL2_AC_MODE | ANX9804_RST_CTRL2_AUX);
96 	i2c_reg_write(0x39, ANX9804_RST_CTRL2_REG,
97 		      ANX9804_RST_CTRL2_AC_MODE);
98 
99 	/* Powerdown audio and some other unused bits */
100 	i2c_reg_write(0x39, ANX9804_POWERD_CTRL_REG, ANX9804_POWERD_AUDIO);
101 	i2c_reg_write(0x38, ANX9804_HDCP_CONTROL_0_REG, 0x00);
102 	i2c_reg_write(0x38, 0xa7, 0x00);
103 
104 	/* Set data-rate / lanes */
105 	i2c_reg_write(0x38, ANX9804_LINK_BW_SET_REG, data_rate);
106 	i2c_reg_write(0x38, ANX9804_LANE_COUNT_SET_REG, lanes);
107 
108 	/* Link training */
109 	i2c_reg_write(0x38, ANX9804_LINK_TRAINING_CTRL_REG,
110 		      ANX9804_LINK_TRAINING_CTRL_EN);
111 	mdelay(5);
112 	for (i = 0; i < 100; i++) {
113 		c = i2c_reg_read(0x38, ANX9804_LINK_TRAINING_CTRL_REG);
114 		if ((c & 0x01) == 0)
115 			break;
116 
117 		mdelay(5);
118 	}
119 	if(i == 100) {
120 		printf("Error anx9804 link training timeout\n");
121 		i2c_set_bus_num(orig_i2c_bus);
122 		return;
123 	}
124 
125 	/* Enable */
126 	i2c_reg_write(0x39, ANX9804_VID_CTRL1_REG,
127 		      ANX9804_VID_CTRL1_VID_EN | ANX9804_VID_CTRL1_EDGE);
128 	/* Force stream valid */
129 	i2c_reg_write(0x38, ANX9804_SYS_CTRL3_REG,
130 		      ANX9804_SYS_CTRL3_F_HPD | ANX9804_SYS_CTRL3_HPD_CTRL |
131 		      ANX9804_SYS_CTRL3_F_VALID | ANX9804_SYS_CTRL3_VALID_CTRL);
132 
133 	i2c_set_bus_num(orig_i2c_bus);
134 }
135