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 <drm/drmP.h> |
26 | #include <drm/amdgpu_drm.h> |
27 | #include "amdgpu.h" |
28 | #include "atom.h" |
29 | #include "amdgpu_atombios.h" |
30 | #include "atombios_i2c.h" |
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 3 |
36 | #define ATOM_MAX_HW_I2C_READ 255 |
37 | |
38 | static int amdgpu_atombios_i2c_process_i2c_ch(struct amdgpu_i2c_chan *chan, |
39 | u8 slave_addr, u8 flags, |
40 | u8 *buf, u8 num) |
41 | { |
42 | struct drm_device *dev = chan->dev; |
43 | struct amdgpu_device *adev = dev->dev_private; |
44 | PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args; |
45 | int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction); |
46 | unsigned char *base; |
47 | u16 out = cpu_to_le16(0); |
48 | int r = 0; |
49 | |
50 | memset(&args, 0, sizeof(args)); |
51 | |
52 | mutex_lock(&chan->mutex); |
53 | |
54 | base = (unsigned char *)adev->mode_info.atom_context->scratch; |
55 | |
56 | if (flags & HW_I2C_WRITE) { |
57 | if (num > ATOM_MAX_HW_I2C_WRITE) { |
58 | DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 3)\n" , num); |
59 | r = -EINVAL; |
60 | goto done; |
61 | } |
62 | if (buf == NULL) |
63 | args.ucRegIndex = 0; |
64 | else |
65 | args.ucRegIndex = buf[0]; |
66 | if (num) |
67 | num--; |
68 | if (num) { |
69 | if (buf) { |
70 | memcpy(&out, &buf[1], num); |
71 | } else { |
72 | DRM_ERROR("hw i2c: missing buf with num > 1\n" ); |
73 | r = -EINVAL; |
74 | goto done; |
75 | } |
76 | } |
77 | args.lpI2CDataOut = cpu_to_le16(out); |
78 | } else { |
79 | if (num > ATOM_MAX_HW_I2C_READ) { |
80 | DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n" , num); |
81 | r = -EINVAL; |
82 | goto done; |
83 | } |
84 | args.ucRegIndex = 0; |
85 | args.lpI2CDataOut = 0; |
86 | } |
87 | |
88 | args.ucFlag = flags; |
89 | args.ucI2CSpeed = TARGET_HW_I2C_CLOCK; |
90 | args.ucTransBytes = num; |
91 | args.ucSlaveAddr = slave_addr << 1; |
92 | args.ucLineNumber = chan->rec.i2c_id; |
93 | |
94 | amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args); |
95 | |
96 | /* error */ |
97 | if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) { |
98 | DRM_DEBUG_KMS("hw_i2c error\n" ); |
99 | r = -EIO; |
100 | goto done; |
101 | } |
102 | |
103 | if (!(flags & HW_I2C_WRITE)) |
104 | amdgpu_atombios_copy_swap(buf, base, num, false); |
105 | |
106 | done: |
107 | mutex_unlock(&chan->mutex); |
108 | |
109 | return r; |
110 | } |
111 | |
112 | int amdgpu_atombios_i2c_xfer(struct i2c_adapter *i2c_adap, |
113 | struct i2c_msg *msgs, int num) |
114 | { |
115 | struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap); |
116 | struct i2c_msg *p; |
117 | int i, remaining, current_count, buffer_offset, max_bytes, ret; |
118 | u8 flags; |
119 | |
120 | /* check for bus probe */ |
121 | p = &msgs[0]; |
122 | if ((num == 1) && (p->len == 0)) { |
123 | ret = amdgpu_atombios_i2c_process_i2c_ch(i2c, |
124 | p->addr, HW_I2C_WRITE, |
125 | NULL, 0); |
126 | if (ret) |
127 | return ret; |
128 | else |
129 | return num; |
130 | } |
131 | |
132 | for (i = 0; i < num; i++) { |
133 | p = &msgs[i]; |
134 | remaining = p->len; |
135 | buffer_offset = 0; |
136 | /* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */ |
137 | if (p->flags & I2C_M_RD) { |
138 | max_bytes = ATOM_MAX_HW_I2C_READ; |
139 | flags = HW_I2C_READ; |
140 | } else { |
141 | max_bytes = ATOM_MAX_HW_I2C_WRITE; |
142 | flags = HW_I2C_WRITE; |
143 | } |
144 | while (remaining) { |
145 | if (remaining > max_bytes) |
146 | current_count = max_bytes; |
147 | else |
148 | current_count = remaining; |
149 | ret = amdgpu_atombios_i2c_process_i2c_ch(i2c, |
150 | p->addr, flags, |
151 | &p->buf[buffer_offset], current_count); |
152 | if (ret) |
153 | return ret; |
154 | remaining -= current_count; |
155 | buffer_offset += current_count; |
156 | } |
157 | } |
158 | |
159 | return num; |
160 | } |
161 | |
162 | u32 amdgpu_atombios_i2c_func(struct i2c_adapter *adap) |
163 | { |
164 | return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; |
165 | } |
166 | |
167 | void amdgpu_atombios_i2c_channel_trans(struct amdgpu_device* adev, u8 slave_addr, u8 line_number, u8 offset, u8 data) |
168 | { |
169 | PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args; |
170 | int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction); |
171 | |
172 | args.ucRegIndex = offset; |
173 | args.lpI2CDataOut = data; |
174 | args.ucFlag = 1; |
175 | args.ucI2CSpeed = TARGET_HW_I2C_CLOCK; |
176 | args.ucTransBytes = 1; |
177 | args.ucSlaveAddr = slave_addr; |
178 | args.ucLineNumber = line_number; |
179 | |
180 | amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args); |
181 | } |
182 | |