1 /*
2 * Copyright 2012 Red Hat Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sub license, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
11 *
12 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
13 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
14 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
15 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
16 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
17 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
18 * USE OR OTHER DEALINGS IN THE SOFTWARE.
19 *
20 * The above copyright notice and this permission notice (including the
21 * next paragraph) shall be included in all copies or substantial portions
22 * of the Software.
23 *
24 */
25 /*
26 * Authors: Dave Airlie <airlied@redhat.com>
27 */
28 #include <linux/export.h>
29 #include <linux/i2c.h>
30 #include <linux/i2c-algo-bit.h>
31 #include <drm/drmP.h>
32
33 #include "mgag200_drv.h"
34
mga_i2c_read_gpio(struct mga_device * mdev)35 static int mga_i2c_read_gpio(struct mga_device *mdev)
36 {
37 WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);
38 return RREG8(DAC_DATA);
39 }
40
mga_i2c_set_gpio(struct mga_device * mdev,int mask,int val)41 static void mga_i2c_set_gpio(struct mga_device *mdev, int mask, int val)
42 {
43 int tmp;
44
45 WREG8(DAC_INDEX, MGA1064_GEN_IO_CTL);
46 tmp = (RREG8(DAC_DATA) & mask) | val;
47 WREG_DAC(MGA1064_GEN_IO_CTL, tmp);
48 WREG_DAC(MGA1064_GEN_IO_DATA, 0);
49 }
50
mga_i2c_set(struct mga_device * mdev,int mask,int state)51 static inline void mga_i2c_set(struct mga_device *mdev, int mask, int state)
52 {
53 if (state)
54 state = 0;
55 else
56 state = mask;
57 mga_i2c_set_gpio(mdev, ~mask, state);
58 }
59
mga_gpio_setsda(void * data,int state)60 static void mga_gpio_setsda(void *data, int state)
61 {
62 struct mga_i2c_chan *i2c = data;
63 struct mga_device *mdev = i2c->dev->dev_private;
64 mga_i2c_set(mdev, i2c->data, state);
65 }
66
mga_gpio_setscl(void * data,int state)67 static void mga_gpio_setscl(void *data, int state)
68 {
69 struct mga_i2c_chan *i2c = data;
70 struct mga_device *mdev = i2c->dev->dev_private;
71 mga_i2c_set(mdev, i2c->clock, state);
72 }
73
mga_gpio_getsda(void * data)74 static int mga_gpio_getsda(void *data)
75 {
76 struct mga_i2c_chan *i2c = data;
77 struct mga_device *mdev = i2c->dev->dev_private;
78 return (mga_i2c_read_gpio(mdev) & i2c->data) ? 1 : 0;
79 }
80
mga_gpio_getscl(void * data)81 static int mga_gpio_getscl(void *data)
82 {
83 struct mga_i2c_chan *i2c = data;
84 struct mga_device *mdev = i2c->dev->dev_private;
85 return (mga_i2c_read_gpio(mdev) & i2c->clock) ? 1 : 0;
86 }
87
mgag200_i2c_create(struct drm_device * dev)88 struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
89 {
90 struct mga_device *mdev = dev->dev_private;
91 struct mga_i2c_chan *i2c;
92 int ret;
93 int data, clock;
94
95 WREG_DAC(MGA1064_GEN_IO_CTL2, 1);
96 WREG_DAC(MGA1064_GEN_IO_DATA, 0xff);
97 WREG_DAC(MGA1064_GEN_IO_CTL, 0);
98
99 switch (mdev->type) {
100 case G200_SE_A:
101 case G200_SE_B:
102 case G200_EV:
103 case G200_WB:
104 data = 1;
105 clock = 2;
106 break;
107 case G200_EH:
108 case G200_ER:
109 data = 2;
110 clock = 1;
111 break;
112 default:
113 data = 2;
114 clock = 8;
115 break;
116 }
117
118 i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL);
119 if (!i2c)
120 return NULL;
121
122 i2c->data = data;
123 i2c->clock = clock;
124 i2c->adapter.owner = THIS_MODULE;
125 i2c->adapter.class = I2C_CLASS_DDC;
126 i2c->adapter.dev.parent = &dev->pdev->dev;
127 i2c->dev = dev;
128 i2c_set_adapdata(&i2c->adapter, i2c);
129 snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), "mga i2c");
130
131 i2c->adapter.algo_data = &i2c->bit;
132
133 i2c->bit.udelay = 10;
134 i2c->bit.timeout = 2;
135 i2c->bit.data = i2c;
136 i2c->bit.setsda = mga_gpio_setsda;
137 i2c->bit.setscl = mga_gpio_setscl;
138 i2c->bit.getsda = mga_gpio_getsda;
139 i2c->bit.getscl = mga_gpio_getscl;
140
141 ret = i2c_bit_add_bus(&i2c->adapter);
142 if (ret) {
143 kfree(i2c);
144 i2c = NULL;
145 }
146 return i2c;
147 }
148
mgag200_i2c_destroy(struct mga_i2c_chan * i2c)149 void mgag200_i2c_destroy(struct mga_i2c_chan *i2c)
150 {
151 if (!i2c)
152 return;
153 i2c_del_adapter(&i2c->adapter);
154 kfree(i2c);
155 }
156
157