atombios_i2c.c revision 1.6
1/* $OpenBSD: atombios_i2c.c,v 1.6 2017/07/01 16:14:10 kettenis Exp $ */ 2/* 3 * Copyright 2011 Advanced Micro Devices, Inc. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the "Software"), 7 * to deal in the Software without restriction, including without limitation 8 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 9 * and/or sell copies of the Software, and to permit persons to whom the 10 * Software is furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be included in 13 * all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR 19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 21 * OTHER DEALINGS IN THE SOFTWARE. 22 * 23 * Authors: Alex Deucher 24 * 25 */ 26#include <dev/pci/drm/drmP.h> 27#include <dev/pci/drm/radeon_drm.h> 28#include "radeon.h" 29#include "atom.h" 30 31extern void radeon_atom_copy_swap(u8 *dst, u8 *src, u8 num_bytes, bool to_le); 32 33#define TARGET_HW_I2C_CLOCK 50 34 35/* these are a limitation of ProcessI2cChannelTransaction not the hw */ 36#define ATOM_MAX_HW_I2C_WRITE 2 37#define ATOM_MAX_HW_I2C_READ 255 38 39static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan, 40 u8 slave_addr, u8 flags, 41 u8 *buf, u8 num) 42{ 43 struct drm_device *dev = chan->dev; 44 struct radeon_device *rdev = dev->dev_private; 45 PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args; 46 int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction); 47 unsigned char *base; 48 u16 out = cpu_to_le16(0); 49 50 memset(&args, 0, sizeof(args)); 51 52 base = (unsigned char *)rdev->mode_info.atom_context->scratch; 53 54 if (flags & HW_I2C_WRITE) { 55 if (num > ATOM_MAX_HW_I2C_WRITE) { 56 DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 2)\n", num); 57 return -EINVAL; 58 } 59 if (buf == NULL) 60 args.ucRegIndex = 0; 61 else 62 args.ucRegIndex = buf[0]; 63 if (num) 64 num--; 65 if (num) 66 memcpy(&out, &buf[1], num); 67 args.lpI2CDataOut = cpu_to_le16(out); 68#if 0 69 } else { 70 if (num > ATOM_MAX_HW_I2C_READ) { 71 DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num); 72 return -EINVAL; 73 } 74#endif 75 } 76 77 args.ucI2CSpeed = TARGET_HW_I2C_CLOCK; 78 args.ucRegIndex = 0; 79 args.ucTransBytes = num; 80 args.ucSlaveAddr = slave_addr << 1; 81 args.ucLineNumber = chan->rec.i2c_id; 82 83 atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args); 84 85 /* error */ 86 if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) { 87 DRM_DEBUG_KMS("hw_i2c error\n"); 88 return -EIO; 89 } 90 91 if (!(flags & HW_I2C_WRITE)) 92 radeon_atom_copy_swap(buf, base, num, false); 93 94 return 0; 95} 96 97int radeon_atom_hw_i2c_xfer(struct i2c_adapter *i2c_adap, 98 struct i2c_msg *msgs, int num) 99{ 100 struct radeon_i2c_chan *i2c = i2c_get_adapdata(i2c_adap); 101 struct i2c_msg *p; 102 int i, remaining, current_count, buffer_offset, max_bytes, ret; 103 u8 flags; 104 105 /* check for bus probe */ 106 p = &msgs[0]; 107 if ((num == 1) && (p->len == 0)) { 108 ret = radeon_process_i2c_ch(i2c, 109 p->addr, HW_I2C_WRITE, 110 NULL, 0); 111 if (ret) 112 return ret; 113 else 114 return num; 115 } 116 117 for (i = 0; i < num; i++) { 118 p = &msgs[i]; 119 remaining = p->len; 120 buffer_offset = 0; 121 /* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */ 122 if (p->flags & I2C_M_RD) { 123 max_bytes = ATOM_MAX_HW_I2C_READ; 124 flags = HW_I2C_READ; 125 } else { 126 max_bytes = ATOM_MAX_HW_I2C_WRITE; 127 flags = HW_I2C_WRITE; 128 } 129 while (remaining) { 130 if (remaining > max_bytes) 131 current_count = max_bytes; 132 else 133 current_count = remaining; 134 ret = radeon_process_i2c_ch(i2c, 135 p->addr, flags, 136 &p->buf[buffer_offset], current_count); 137 if (ret) 138 return ret; 139 remaining -= current_count; 140 buffer_offset += current_count; 141 } 142 } 143 144 return num; 145} 146 147#ifdef notyet 148u32 radeon_atom_hw_i2c_func(struct i2c_adapter *adap) 149{ 150 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; 151} 152#endif 153 154