2 * Copyright 2011 Advanced Micro Devices, Inc.
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:
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
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.
22 * Authors: Alex Deucher
26 #include <drm/radeon_drm.h>
30 #define TARGET_HW_I2C_CLOCK 50
32 /* these are a limitation of ProcessI2cChannelTransaction not the hw */
33 #define ATOM_MAX_HW_I2C_WRITE 3
34 #define ATOM_MAX_HW_I2C_READ 255
36 static int radeon_process_i2c_ch(struct radeon_i2c_chan
*chan
,
37 u8 slave_addr
, u8 flags
,
40 struct drm_device
*dev
= chan
->dev
;
41 struct radeon_device
*rdev
= dev
->dev_private
;
42 PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args
;
43 int index
= GetIndexIntoMasterTable(COMMAND
, ProcessI2cChannelTransaction
);
45 u16 out
= cpu_to_le16(0);
48 memset(&args
, 0, sizeof(args
));
50 mutex_lock(&chan
->mutex
);
51 mutex_lock(&rdev
->mode_info
.atom_context
->scratch_mutex
);
53 base
= (unsigned char *)rdev
->mode_info
.atom_context
->scratch
;
55 if (flags
& HW_I2C_WRITE
) {
56 if (num
> ATOM_MAX_HW_I2C_WRITE
) {
57 DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 3)\n", num
);
64 args
.ucRegIndex
= buf
[0];
68 memcpy(&out
, &buf
[1], num
);
69 args
.lpI2CDataOut
= cpu_to_le16(out
);
71 if (num
> ATOM_MAX_HW_I2C_READ
) {
72 DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num
);
77 args
.lpI2CDataOut
= 0;
81 args
.ucI2CSpeed
= TARGET_HW_I2C_CLOCK
;
82 args
.ucTransBytes
= num
;
83 args
.ucSlaveAddr
= slave_addr
<< 1;
84 args
.ucLineNumber
= chan
->rec
.i2c_id
;
86 atom_execute_table_scratch_unlocked(rdev
->mode_info
.atom_context
, index
, (uint32_t *)&args
);
89 if (args
.ucStatus
!= HW_ASSISTED_I2C_STATUS_SUCCESS
) {
90 DRM_DEBUG_KMS("hw_i2c error\n");
95 if (!(flags
& HW_I2C_WRITE
))
96 radeon_atom_copy_swap(buf
, base
, num
, false);
99 mutex_unlock(&rdev
->mode_info
.atom_context
->scratch_mutex
);
100 mutex_unlock(&chan
->mutex
);
105 int radeon_atom_hw_i2c_xfer(struct i2c_adapter
*i2c_adap
,
106 struct i2c_msg
*msgs
, int num
)
108 struct radeon_i2c_chan
*i2c
= i2c_get_adapdata(i2c_adap
);
110 int i
, remaining
, current_count
, buffer_offset
, max_bytes
, ret
;
113 /* check for bus probe */
115 if ((num
== 1) && (p
->len
== 0)) {
116 ret
= radeon_process_i2c_ch(i2c
,
117 p
->addr
, HW_I2C_WRITE
,
125 for (i
= 0; i
< num
; i
++) {
129 /* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */
130 if (p
->flags
& I2C_M_RD
) {
131 max_bytes
= ATOM_MAX_HW_I2C_READ
;
134 max_bytes
= ATOM_MAX_HW_I2C_WRITE
;
135 flags
= HW_I2C_WRITE
;
138 if (remaining
> max_bytes
)
139 current_count
= max_bytes
;
141 current_count
= remaining
;
142 ret
= radeon_process_i2c_ch(i2c
,
144 &p
->buf
[buffer_offset
], current_count
);
147 remaining
-= current_count
;
148 buffer_offset
+= current_count
;
155 u32
radeon_atom_hw_i2c_func(struct i2c_adapter
*adap
)
157 return I2C_FUNC_I2C
| I2C_FUNC_SMBUS_EMUL
;