/*
* Copyright 2011 Advanced Micro Devices, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
* Authors: Alex Deucher
*
*/
#include <drm/drmP.h>
#include <drm/radeon_drm.h>
#include "radeon.h"
#include "atom.h"
#define TARGET_HW_I2C_CLOCK 50
/* these are a limitation of ProcessI2cChannelTransaction not the hw */
#define ATOM_MAX_HW_I2C_WRITE 2
#define ATOM_MAX_HW_I2C_READ 255
static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
u8 slave_addr, u8 flags,
u8 *buf, u8 num)
{
struct drm_device *dev = chan->dev;
struct radeon_device *rdev = dev->dev_private;
PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args;
int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction);
unsigned char *base;
u16 out;
memset(&args, 0, sizeof(args));
base = (unsigned char *)rdev->mode_info.atom_context->scratch;
if (flags & HW_I2C_WRITE) {
if (num > ATOM_MAX_HW_I2C_WRITE) {
DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 2)\n", num);
return -EINVAL;
}
memcpy(&out, buf, num);
args.lpI2CDataOut = cpu_to_le16(out);
} else {
if (num > ATOM_MAX_HW_I2C_READ) {
DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num);
return -EINVAL;
}
}
args.ucI2CSpeed = TARGET_HW_I2C_CLOCK;
args.ucRegIndex = 0;
args.ucTransBytes = num;
args.ucSlaveAddr = slave_addr << 1;
args.ucLineNumber = chan->rec.i2c_id;
atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
/* error */
if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) {
DRM_DEBUG_KMS("hw_i2c error\n");
return -EIO;
}
if (!(flags & HW_I2C_WRITE))
memcpy(buf, base, num);
return 0;
}
int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap,
struct i2c_msg *msgs, int num)
{
struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);
struct i2c_msg *p;
int i, remaining, current_count, buffer_offset, max_bytes, ret;
u8 buf = 0, flags;
/* check for bus probe */
p = &msgs[0];
if ((num == 1) && (p->len == 0)) {
ret = radeon_process_i2c_ch(i2c,
p->addr, HW_I2C_WRITE,
&buf, 1);
if (ret)
return ret;
else
return num;
}
for (i = 0; i < num; i++) {
p = &msgs[i];
remaining = p->len;
buffer_offset = 0;
/* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */
if (p->flags & I2C_M_RD) {
max_bytes = ATOM_MAX_HW_I2C_READ;
flags = HW_I2C_READ;
} else {
max_bytes = ATOM_MAX_HW_I2C_WRITE;
flags = HW_I2C_WRITE;
}
while (remaining) {
if (remaining > max_bytes)
current_count = max_bytes;
else
current_count = remaining;
ret = radeon_process_i2c_ch(i2c,
p->addr, flags,
&p->buf[buffer_offset], current_count);
if (ret)
return ret;
remaining -= current_count;
buffer_offset += current_count;
}
}
return num;
}
u32 radeon_atom_hw_i2c_func(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}
