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 2
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
);
47 memset(&args
, 0, sizeof(args
));
49 base
= (unsigned char *)rdev
->mode_info
.atom_context
->scratch
;
51 if (flags
& HW_I2C_WRITE
) {
52 if (num
> ATOM_MAX_HW_I2C_WRITE
) {
53 DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 2)\n", num
);
56 memcpy(&out
, buf
, num
);
57 args
.lpI2CDataOut
= cpu_to_le16(out
);
59 if (num
> ATOM_MAX_HW_I2C_READ
) {
60 DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num
);
65 args
.ucI2CSpeed
= TARGET_HW_I2C_CLOCK
;
67 args
.ucTransBytes
= num
;
68 args
.ucSlaveAddr
= slave_addr
<< 1;
69 args
.ucLineNumber
= chan
->rec
.i2c_id
;
71 atom_execute_table(rdev
->mode_info
.atom_context
, index
, (uint32_t *)&args
);
74 if (args
.ucStatus
!= HW_ASSISTED_I2C_STATUS_SUCCESS
) {
75 DRM_DEBUG_KMS("hw_i2c error\n");
79 if (!(flags
& HW_I2C_WRITE
))
80 memcpy(buf
, base
, num
);
85 int radeon_atom_hw_i2c_xfer(struct i2c_adapter
*i2c_adap
,
86 struct i2c_msg
*msgs
, int num
)
88 struct radeon_i2c_chan
*i2c
= i2c_get_adapdata(i2c_adap
);
90 int i
, remaining
, current_count
, buffer_offset
, max_bytes
, ret
;
93 /* check for bus probe */
95 if ((num
== 1) && (p
->len
== 0)) {
96 ret
= radeon_process_i2c_ch(i2c
,
97 p
->addr
, HW_I2C_WRITE
,
105 for (i
= 0; i
< num
; i
++) {
109 /* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */
110 if (p
->flags
& I2C_M_RD
) {
111 max_bytes
= ATOM_MAX_HW_I2C_READ
;
114 max_bytes
= ATOM_MAX_HW_I2C_WRITE
;
115 flags
= HW_I2C_WRITE
;
118 if (remaining
> max_bytes
)
119 current_count
= max_bytes
;
121 current_count
= remaining
;
122 ret
= radeon_process_i2c_ch(i2c
,
124 &p
->buf
[buffer_offset
], current_count
);
127 remaining
-= current_count
;
128 buffer_offset
+= current_count
;
135 u32
radeon_atom_hw_i2c_func(struct i2c_adapter
*adap
)
137 return I2C_FUNC_I2C
| I2C_FUNC_SMBUS_EMUL
;