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
29#include <linux/export.h>
30#include <linux/i2c-algo-bit.h>
31#include <linux/i2c.h>
32#include <linux/pci.h>
33
34#include "mgag200_drv.h"
35
36static int mga_i2c_read_gpio(struct mga_device *mdev)
37{
38	WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);
39	return RREG8(DAC_DATA);
40}
41
42static void mga_i2c_set_gpio(struct mga_device *mdev, int mask, int val)
43{
44	int tmp;
45
46	WREG8(DAC_INDEX, MGA1064_GEN_IO_CTL);
47	tmp = (RREG8(DAC_DATA) & mask) | val;
48	WREG_DAC(MGA1064_GEN_IO_CTL, tmp);
49	WREG_DAC(MGA1064_GEN_IO_DATA, 0);
50}
51
52static inline void mga_i2c_set(struct mga_device *mdev, int mask, int state)
53{
54	if (state)
55		state = 0;
56	else
57		state = mask;
58	mga_i2c_set_gpio(mdev, ~mask, state);
59}
60
61static void mga_gpio_setsda(void *data, int state)
62{
63	struct mga_i2c_chan *i2c = data;
64	struct mga_device *mdev = to_mga_device(i2c->dev);
65	mga_i2c_set(mdev, i2c->data, state);
66}
67
68static void mga_gpio_setscl(void *data, int state)
69{
70	struct mga_i2c_chan *i2c = data;
71	struct mga_device *mdev = to_mga_device(i2c->dev);
72	mga_i2c_set(mdev, i2c->clock, state);
73}
74
75static int mga_gpio_getsda(void *data)
76{
77	struct mga_i2c_chan *i2c = data;
78	struct mga_device *mdev = to_mga_device(i2c->dev);
79	return (mga_i2c_read_gpio(mdev) & i2c->data) ? 1 : 0;
80}
81
82static int mga_gpio_getscl(void *data)
83{
84	struct mga_i2c_chan *i2c = data;
85	struct mga_device *mdev = to_mga_device(i2c->dev);
86	return (mga_i2c_read_gpio(mdev) & i2c->clock) ? 1 : 0;
87}
88
89struct mga_i2c_chan *mgag200_i2c_create(struct drm_device *dev)
90{
91	struct mga_device *mdev = to_mga_device(dev);
92	struct mga_i2c_chan *i2c;
93	int ret;
94	int data, clock;
95
96	WREG_DAC(MGA1064_GEN_IO_CTL2, 1);
97	WREG_DAC(MGA1064_GEN_IO_DATA, 0xff);
98	WREG_DAC(MGA1064_GEN_IO_CTL, 0);
99
100	switch (mdev->type) {
101	case G200_SE_A:
102	case G200_SE_B:
103	case G200_EV:
104	case G200_WB:
105	case G200_EW3:
106		data = 1;
107		clock = 2;
108		break;
109	case G200_EH:
110	case G200_EH3:
111	case G200_ER:
112		data = 2;
113		clock = 1;
114		break;
115	default:
116		data = 2;
117		clock = 8;
118		break;
119	}
120
121	i2c = kzalloc(sizeof(struct mga_i2c_chan), GFP_KERNEL);
122	if (!i2c)
123		return NULL;
124
125	i2c->data = data;
126	i2c->clock = clock;
127	i2c->adapter.owner = THIS_MODULE;
128	i2c->adapter.class = I2C_CLASS_DDC;
129	i2c->adapter.dev.parent = &dev->pdev->dev;
130	i2c->dev = dev;
131	i2c_set_adapdata(&i2c->adapter, i2c);
132	snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), "mga i2c");
133
134	i2c->adapter.algo_data = &i2c->bit;
135
136	i2c->bit.udelay = 10;
137	i2c->bit.timeout = 2;
138	i2c->bit.data = i2c;
139	i2c->bit.setsda		= mga_gpio_setsda;
140	i2c->bit.setscl		= mga_gpio_setscl;
141	i2c->bit.getsda		= mga_gpio_getsda;
142	i2c->bit.getscl		= mga_gpio_getscl;
143
144	ret = i2c_bit_add_bus(&i2c->adapter);
145	if (ret) {
146		kfree(i2c);
147		i2c = NULL;
148	}
149	return i2c;
150}
151
152void mgag200_i2c_destroy(struct mga_i2c_chan *i2c)
153{
154	if (!i2c)
155		return;
156	i2c_del_adapter(&i2c->adapter);
157	kfree(i2c);
158}
159
160