1 // SPDX-License-Identifier: GPL-2.0
2 #include "radeonfb.h"
3 
4 #include <linux/module.h>
5 #include <linux/kernel.h>
6 #include <linux/delay.h>
7 #include <linux/fb.h>
8 
9 
10 #include <linux/i2c.h>
11 #include <linux/i2c-algo-bit.h>
12 
13 #include <asm/io.h>
14 
15 #include <video/radeon.h>
16 #include "../edid.h"
17 
18 static void radeon_gpio_setscl(void* data, int state)
19 {
20 	struct radeon_i2c_chan 	*chan = data;
21 	struct radeonfb_info	*rinfo = chan->rinfo;
22 	u32			val;
23 
24 	val = INREG(chan->ddc_reg) & ~(VGA_DDC_CLK_OUT_EN);
25 	if (!state)
26 		val |= VGA_DDC_CLK_OUT_EN;
27 
28 	OUTREG(chan->ddc_reg, val);
29 	(void)INREG(chan->ddc_reg);
30 }
31 
32 static void radeon_gpio_setsda(void* data, int state)
33 {
34 	struct radeon_i2c_chan 	*chan = data;
35 	struct radeonfb_info	*rinfo = chan->rinfo;
36 	u32			val;
37 
38 	val = INREG(chan->ddc_reg) & ~(VGA_DDC_DATA_OUT_EN);
39 	if (!state)
40 		val |= VGA_DDC_DATA_OUT_EN;
41 
42 	OUTREG(chan->ddc_reg, val);
43 	(void)INREG(chan->ddc_reg);
44 }
45 
46 static int radeon_gpio_getscl(void* data)
47 {
48 	struct radeon_i2c_chan 	*chan = data;
49 	struct radeonfb_info	*rinfo = chan->rinfo;
50 	u32			val;
51 
52 	val = INREG(chan->ddc_reg);
53 
54 	return (val & VGA_DDC_CLK_INPUT) ? 1 : 0;
55 }
56 
57 static int radeon_gpio_getsda(void* data)
58 {
59 	struct radeon_i2c_chan 	*chan = data;
60 	struct radeonfb_info	*rinfo = chan->rinfo;
61 	u32			val;
62 
63 	val = INREG(chan->ddc_reg);
64 
65 	return (val & VGA_DDC_DATA_INPUT) ? 1 : 0;
66 }
67 
68 static int radeon_setup_i2c_bus(struct radeon_i2c_chan *chan, const char *name)
69 {
70 	int rc;
71 
72 	snprintf(chan->adapter.name, sizeof(chan->adapter.name),
73 		 "radeonfb %s", name);
74 	chan->adapter.owner		= THIS_MODULE;
75 	chan->adapter.algo_data		= &chan->algo;
76 	chan->adapter.dev.parent	= &chan->rinfo->pdev->dev;
77 	chan->algo.setsda		= radeon_gpio_setsda;
78 	chan->algo.setscl		= radeon_gpio_setscl;
79 	chan->algo.getsda		= radeon_gpio_getsda;
80 	chan->algo.getscl		= radeon_gpio_getscl;
81 	chan->algo.udelay		= 10;
82 	chan->algo.timeout		= 20;
83 	chan->algo.data 		= chan;
84 
85 	i2c_set_adapdata(&chan->adapter, chan);
86 
87 	/* Raise SCL and SDA */
88 	radeon_gpio_setsda(chan, 1);
89 	radeon_gpio_setscl(chan, 1);
90 	udelay(20);
91 
92 	rc = i2c_bit_add_bus(&chan->adapter);
93 	if (rc == 0)
94 		dev_dbg(&chan->rinfo->pdev->dev, "I2C bus %s registered.\n", name);
95 	else
96 		dev_warn(&chan->rinfo->pdev->dev, "Failed to register I2C bus %s.\n", name);
97 	return rc;
98 }
99 
100 void radeon_create_i2c_busses(struct radeonfb_info *rinfo)
101 {
102 	rinfo->i2c[0].rinfo	= rinfo;
103 	rinfo->i2c[0].ddc_reg	= GPIO_MONID;
104 #ifndef CONFIG_PPC
105 	rinfo->i2c[0].adapter.class = I2C_CLASS_HWMON;
106 #endif
107 	radeon_setup_i2c_bus(&rinfo->i2c[0], "monid");
108 
109 	rinfo->i2c[1].rinfo	= rinfo;
110 	rinfo->i2c[1].ddc_reg	= GPIO_DVI_DDC;
111 	radeon_setup_i2c_bus(&rinfo->i2c[1], "dvi");
112 
113 	rinfo->i2c[2].rinfo	= rinfo;
114 	rinfo->i2c[2].ddc_reg	= GPIO_VGA_DDC;
115 	radeon_setup_i2c_bus(&rinfo->i2c[2], "vga");
116 
117 	rinfo->i2c[3].rinfo	= rinfo;
118 	rinfo->i2c[3].ddc_reg	= GPIO_CRT2_DDC;
119 	radeon_setup_i2c_bus(&rinfo->i2c[3], "crt2");
120 }
121 
122 void radeon_delete_i2c_busses(struct radeonfb_info *rinfo)
123 {
124 	if (rinfo->i2c[0].rinfo)
125 		i2c_del_adapter(&rinfo->i2c[0].adapter);
126 	rinfo->i2c[0].rinfo = NULL;
127 
128 	if (rinfo->i2c[1].rinfo)
129 		i2c_del_adapter(&rinfo->i2c[1].adapter);
130 	rinfo->i2c[1].rinfo = NULL;
131 
132 	if (rinfo->i2c[2].rinfo)
133 		i2c_del_adapter(&rinfo->i2c[2].adapter);
134 	rinfo->i2c[2].rinfo = NULL;
135 
136 	if (rinfo->i2c[3].rinfo)
137 		i2c_del_adapter(&rinfo->i2c[3].adapter);
138 	rinfo->i2c[3].rinfo = NULL;
139 }
140 
141 int radeon_probe_i2c_connector(struct radeonfb_info *rinfo, int conn,
142 			       u8 **out_edid)
143 {
144 	u8 *edid;
145 
146 	edid = fb_ddc_read(&rinfo->i2c[conn-1].adapter);
147 
148 	if (out_edid)
149 		*out_edid = edid;
150 	if (!edid) {
151 		pr_debug("radeonfb: I2C (port %d) ... not found\n", conn);
152 		return MT_NONE;
153 	}
154 	if (edid[0x14] & 0x80) {
155 		/* Fix detection using BIOS tables */
156 		if (rinfo->is_mobility /*&& conn == ddc_dvi*/ &&
157 		    (INREG(LVDS_GEN_CNTL) & LVDS_ON)) {
158 			pr_debug("radeonfb: I2C (port %d) ... found LVDS panel\n", conn);
159 			return MT_LCD;
160 		} else {
161 			pr_debug("radeonfb: I2C (port %d) ... found TMDS panel\n", conn);
162 			return MT_DFP;
163 		}
164 	}
165 	pr_debug("radeonfb: I2C (port %d) ... found CRT display\n", conn);
166 	return MT_CRT;
167 }
168 
169