diff options
Diffstat (limited to 'drivers/gpu/drm/amd/amdgpu/atombios_i2c.c')
| -rw-r--r-- | drivers/gpu/drm/amd/amdgpu/atombios_i2c.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c b/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c new file mode 100644 index 000000000000..13cdb01e9b45 --- /dev/null +++ b/drivers/gpu/drm/amd/amdgpu/atombios_i2c.c @@ -0,0 +1,158 @@ +/* + * 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/amdgpu_drm.h> +#include "amdgpu.h" +#include "atom.h" +#include "amdgpu_atombios.h" + +#define TARGET_HW_I2C_CLOCK 50 + +/* these are a limitation of ProcessI2cChannelTransaction not the hw */ +#define ATOM_MAX_HW_I2C_WRITE 3 +#define ATOM_MAX_HW_I2C_READ 255 + +static int amdgpu_atombios_i2c_process_i2c_ch(struct amdgpu_i2c_chan *chan, + u8 slave_addr, u8 flags, + u8 *buf, u8 num) +{ + struct drm_device *dev = chan->dev; + struct amdgpu_device *adev = dev->dev_private; + PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args; + int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction); + unsigned char *base; + u16 out = cpu_to_le16(0); + int r = 0; + + memset(&args, 0, sizeof(args)); + + mutex_lock(&chan->mutex); + + base = (unsigned char *)adev->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 3)\n", num); + r = -EINVAL; + goto done; + } + if (buf == NULL) + args.ucRegIndex = 0; + else + args.ucRegIndex = buf[0]; + if (num) + num--; + if (num) + memcpy(&out, &buf[1], 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); + r = -EINVAL; + goto done; + } + args.ucRegIndex = 0; + args.lpI2CDataOut = 0; + } + + args.ucFlag = flags; + args.ucI2CSpeed = TARGET_HW_I2C_CLOCK; + args.ucTransBytes = num; + args.ucSlaveAddr = slave_addr << 1; + args.ucLineNumber = chan->rec.i2c_id; + + amdgpu_atom_execute_table(adev->mode_info.atom_context, index, (uint32_t *)&args); + + /* error */ + if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) { + DRM_DEBUG_KMS("hw_i2c error\n"); + r = -EIO; + goto done; + } + + if (!(flags & HW_I2C_WRITE)) + amdgpu_atombios_copy_swap(buf, base, num, false); + +done: + mutex_unlock(&chan->mutex); + + return r; +} + +int amdgpu_atombios_i2c_xfer(struct i2c_adapter *i2c_adap, + struct i2c_msg *msgs, int num) +{ + struct amdgpu_i2c_chan *i2c = i2c_get_adapdata(i2c_adap); + struct i2c_msg *p; + int i, remaining, current_count, buffer_offset, max_bytes, ret; + u8 flags; + + /* check for bus probe */ + p = &msgs[0]; + if ((num == 1) && (p->len == 0)) { + ret = amdgpu_atombios_i2c_process_i2c_ch(i2c, + p->addr, HW_I2C_WRITE, + NULL, 0); + 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 = amdgpu_atombios_i2c_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 amdgpu_atombios_i2c_func(struct i2c_adapter *adap) +{ + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; +} + |