1 /*
2 * Copyright 2011 Advanced Micro Devices, 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 "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 * Authors: Alex Deucher
23 *
24 */
25 #include "drmP.h"
26 #include "radeon_drm.h"
27 #include "radeon.h"
28 #include "atom.h"
29
30 extern void radeon_atom_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le);
31
32 #define TARGET_HW_I2C_CLOCK 50
33
34 /* these are a limitation of ProcessI2cChannelTransaction not the hw */
35 #define ATOM_MAX_HW_I2C_WRITE 2
36 #define ATOM_MAX_HW_I2C_READ 255
37
radeon_process_i2c_ch(struct radeon_i2c_chan * chan,u8 slave_addr,u8 flags,u8 * buf,u8 num)38 static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
39 u8 slave_addr, u8 flags,
40 u8 *buf, u8 num)
41 {
42 struct drm_device *dev = chan->dev;
43 struct radeon_device *rdev = dev->dev_private;
44 PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args;
45 int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction);
46 unsigned char *base;
47 u16 out;
48
49 memset(&args, 0, sizeof(args));
50
51 base = (unsigned char *)rdev->mode_info.atom_context->scratch;
52
53 if (flags & HW_I2C_WRITE) {
54 if (num > ATOM_MAX_HW_I2C_WRITE) {
55 DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 2)\n", num);
56 return -EINVAL;
57 }
58 memcpy(&out, buf, num);
59 args.lpI2CDataOut = cpu_to_le16(out);
60 } else {
61 if (num > ATOM_MAX_HW_I2C_READ) {
62 DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num);
63 return -EINVAL;
64 }
65 }
66
67 args.ucI2CSpeed = TARGET_HW_I2C_CLOCK;
68 args.ucRegIndex = 0;
69 args.ucTransBytes = num;
70 args.ucSlaveAddr = slave_addr << 1;
71 args.ucLineNumber = chan->rec.i2c_id;
72
73 atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
74
75 /* error */
76 if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) {
77 DRM_DEBUG_KMS("hw_i2c error\n");
78 return -EIO;
79 }
80
81 if (!(flags & HW_I2C_WRITE))
82 radeon_atom_copy_swap(buf, base, num, false);
83
84 return 0;
85 }
86
radeon_atom_hw_i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)87 int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
88 struct i2c_msg *msgs, int num)
89 {
90 struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
91 struct i2c_msg *p;
92 int i, remaining, current_count, buffer_offset, max_bytes, ret;
93 u8 buf = 0, flags;
94
95 /* check for bus probe */
96 p = &msgs[0];
97 if ((num == 1) && (p->len == 0)) {
98 ret = radeon_process_i2c_ch(i2c,
99 p->addr, HW_I2C_WRITE,
100 &buf, 1);
101 if (ret)
102 return ret;
103 else
104 return num;
105 }
106
107 for (i = 0; i < num; i++) {
108 p = &msgs[i];
109 remaining = p->len;
110 buffer_offset = 0;
111 /* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */
112 if (p->flags & I2C_M_RD) {
113 max_bytes = ATOM_MAX_HW_I2C_READ;
114 flags = HW_I2C_READ;
115 } else {
116 max_bytes = ATOM_MAX_HW_I2C_WRITE;
117 flags = HW_I2C_WRITE;
118 }
119 while (remaining) {
120 if (remaining > max_bytes)
121 current_count = max_bytes;
122 else
123 current_count = remaining;
124 ret = radeon_process_i2c_ch(i2c,
125 p->addr, flags,
126 &p->buf[buffer_offset], current_count);
127 if (ret)
128 return ret;
129 remaining -= current_count;
130 buffer_offset += current_count;
131 }
132 }
133
134 return num;
135 }
136
radeon_atom_hw_i2c_func(struct i2c_adapter * adap)137 u32 radeon_atom_hw_i2c_func(struct i2c_adapter *adap)
138 {
139 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
140 }
141
142