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1/*2 * Copyright 2011 Advanced Micro Devices, Inc.3 *4 * Permission is hereby granted, free of charge, to any person obtaining a5 * copy of this software and associated documentation files (the "Software"),6 * to deal in the Software without restriction, including without limitation7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,8 * and/or sell copies of the Software, and to permit persons to whom the9 * Software is furnished to do so, subject to the following conditions:10 *11 * The above copyright notice and this permission notice shall be included in12 * all copies or substantial portions of the Software.13 *14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR18 * 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 OR20 * OTHER DEALINGS IN THE SOFTWARE.21 *22 * Authors: Alex Deucher23 *24 */25 26#include <drm/radeon_drm.h>27#include "radeon.h"28#include "atom.h"29 30#define TARGET_HW_I2C_CLOCK 5031 32/* these are a limitation of ProcessI2cChannelTransaction not the hw */33#define ATOM_MAX_HW_I2C_WRITE 334#define ATOM_MAX_HW_I2C_READ 25535 36static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,37 u8 slave_addr, u8 flags,38 u8 *buf, int num)39{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);44 unsigned char *base;45 u16 out = cpu_to_le16(0);46 int r = 0;47 48 memset(&args, 0, sizeof(args));49 50 mutex_lock(&chan->mutex);51 mutex_lock(&rdev->mode_info.atom_context->scratch_mutex);52 53 base = (unsigned char *)rdev->mode_info.atom_context->scratch;54 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);58 r = -EINVAL;59 goto done;60 }61 if (buf == NULL)62 args.ucRegIndex = 0;63 else64 args.ucRegIndex = buf[0];65 if (num)66 num--;67 if (num)68 memcpy(&out, &buf[1], num);69 args.lpI2CDataOut = cpu_to_le16(out);70 } else {71 args.ucRegIndex = 0;72 args.lpI2CDataOut = 0;73 }74 75 args.ucFlag = flags;76 args.ucI2CSpeed = TARGET_HW_I2C_CLOCK;77 args.ucTransBytes = num;78 args.ucSlaveAddr = slave_addr << 1;79 args.ucLineNumber = chan->rec.i2c_id;80 81 atom_execute_table_scratch_unlocked(rdev->mode_info.atom_context, index, (uint32_t *)&args, sizeof(args));82 83 /* error */84 if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) {85 DRM_DEBUG_KMS("hw_i2c error\n");86 r = -EIO;87 goto done;88 }89 90 if (!(flags & HW_I2C_WRITE))91 radeon_atom_copy_swap(buf, base, num, false);92 93done:94 mutex_unlock(&rdev->mode_info.atom_context->scratch_mutex);95 mutex_unlock(&chan->mutex);96 97 return r;98}99 100int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap,101 struct i2c_msg *msgs, int num)102{103 struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap);104 struct i2c_msg *p;105 int i, remaining, current_count, buffer_offset, max_bytes, ret;106 u8 flags;107 108 /* check for bus probe */109 p = &msgs[0];110 if ((num == 1) && (p->len == 0)) {111 ret = radeon_process_i2c_ch(i2c,112 p->addr, HW_I2C_WRITE,113 NULL, 0);114 if (ret)115 return ret;116 else117 return num;118 }119 120 for (i = 0; i < num; i++) {121 p = &msgs[i];122 remaining = p->len;123 buffer_offset = 0;124 /* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */125 if (p->flags & I2C_M_RD) {126 max_bytes = ATOM_MAX_HW_I2C_READ;127 flags = HW_I2C_READ;128 } else {129 max_bytes = ATOM_MAX_HW_I2C_WRITE;130 flags = HW_I2C_WRITE;131 }132 while (remaining) {133 if (remaining > max_bytes)134 current_count = max_bytes;135 else136 current_count = remaining;137 ret = radeon_process_i2c_ch(i2c,138 p->addr, flags,139 &p->buf[buffer_offset], current_count);140 if (ret)141 return ret;142 remaining -= current_count;143 buffer_offset += current_count;144 }145 }146 147 return num;148}149 150u32 radeon_atom_hw_i2c_func(struct i2c_adapter *adap)151{152 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;153}154 155