sys/dev/drm2/radeon/atombios_i2c.c

   1 /*
   2  * Copyright 2011 Advanced Micro Devices, Inc.
   3  *
   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:
  10  *
  11  * The above copyright notice and this permission notice shall be included in
  12  * all copies or substantial portions of the Software.
  13  *
  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.
  21  *
  22  * Authors: Alex Deucher
  23  *
  24  */
  25
  26 #include <sys/cdefs.h>
  27 __FBSDID("$FreeBSD$");
  28
  29 #include <dev/drm2/drmP.h>
  30 #include <dev/drm2/radeon/radeon_drm.h>
  31 #include <dev/iicbus/iic.h>
  32 #include <dev/iicbus/iiconf.h>
  33 #include <dev/iicbus/iicbus.h>
  34 #include "radeon.h"
  35 #include "atom.h"
  36 #include "iicbus_if.h"
  37 #include "iicbb_if.h"
  38
  39 #define TARGET_HW_I2C_CLOCK 50
  40
  41 /* these are a limitation of ProcessI2cChannelTransaction not the hw */
  42 #define ATOM_MAX_HW_I2C_WRITE 2
  43 #define ATOM_MAX_HW_I2C_READ  255
  44
  45 static int radeon_process_i2c_ch(struct radeon_i2c_chan *chan,
  46                                  u8 slave_addr, u8 flags,
  47                                  u8 *buf, u8 num)
  48 {
  49         struct drm_device *dev = chan->dev;
  50         struct radeon_device *rdev = dev->dev_private;
  51         PROCESS_I2C_CHANNEL_TRANSACTION_PS_ALLOCATION args;
  52         int index = GetIndexIntoMasterTable(COMMAND, ProcessI2cChannelTransaction);
  53         unsigned char *base;
  54         u16 out;
  55
  56         memset(&args, 0, sizeof(args));
  57
  58         base = (unsigned char *)rdev->mode_info.atom_context->scratch;
  59
  60         if (flags & HW_I2C_WRITE) {
  61                 if (num > ATOM_MAX_HW_I2C_WRITE) {
  62                         DRM_ERROR("hw i2c: tried to write too many bytes (%d vs 2)\n", num);
  63                         return -EINVAL;
  64                 }
  65                 memcpy(&out, buf, num);
  66                 args.lpI2CDataOut = cpu_to_le16(out);
  67         } else {
  68 #ifdef FREEBSD_WIP /* FreeBSD: to please GCC 4.2. */
  69                 if (num > ATOM_MAX_HW_I2C_READ) {
  70                         DRM_ERROR("hw i2c: tried to read too many bytes (%d vs 255)\n", num);
  71                         return -EINVAL;
  72                 }
  73 #endif
  74         }
  75
  76         args.ucI2CSpeed = TARGET_HW_I2C_CLOCK;
  77         args.ucRegIndex = 0;
  78         args.ucTransBytes = num;
  79         args.ucSlaveAddr = slave_addr << 1;
  80         args.ucLineNumber = chan->rec.i2c_id;
  81
  82         atom_execute_table(rdev->mode_info.atom_context, index, (uint32_t *)&args);
  83
  84         /* error */
  85         if (args.ucStatus != HW_ASSISTED_I2C_STATUS_SUCCESS) {
  86                 DRM_DEBUG_KMS("hw_i2c error\n");
  87                 return -EIO;
  88         }
  89
  90         if (!(flags & HW_I2C_WRITE))
  91                 memcpy(buf, base, num);
  92
  93         return 0;
  94 }
  95
  96 static int
  97 radeon_atom_hw_i2c_xfer(device_t dev, struct iic_msg *msgs, u_int num)
  98 {
  99         struct radeon_i2c_chan *i2c = device_get_softc(dev);
 100         struct iic_msg *p;
 101         int i, remaining, current_count, buffer_offset, max_bytes, ret;
 102         u8 buf = 0, flags;
 103
 104         /* check for bus probe */
 105         p = &msgs[0];
 106         if ((num == 1) && (p->len == 0)) {
 107                 ret = radeon_process_i2c_ch(i2c,
 108                                             p->slave, HW_I2C_WRITE,
 109                                             &buf, 1);
 110                 if (ret)
 111                         return -ret; /* "ret" is returned on Linux. */
 112                 else
 113                         return (0); /* "num" is returned on Linux. */
 114         }
 115
 116         for (i = 0; i < num; i++) {
 117                 p = &msgs[i];
 118                 remaining = p->len;
 119                 buffer_offset = 0;
 120                 /* max_bytes are a limitation of ProcessI2cChannelTransaction not the hw */
 121                 if (p->flags & IIC_M_RD) {
 122                         max_bytes = ATOM_MAX_HW_I2C_READ;
 123                         flags = HW_I2C_READ;
 124                 } else {
 125                         max_bytes = ATOM_MAX_HW_I2C_WRITE;
 126                         flags = HW_I2C_WRITE;
 127                 }
 128                 while (remaining) {
 129                         if (remaining > max_bytes)
 130                                 current_count = max_bytes;
 131                         else
 132                                 current_count = remaining;
 133                         ret = radeon_process_i2c_ch(i2c,
 134                                                     p->slave, flags,
 135                                                     &p->buf[buffer_offset], current_count);
 136                         if (ret)
 137                                 return -ret; /* "ret" is returned on Linux. */
 138                         remaining -= current_count;
 139                         buffer_offset += current_count;
 140                 }
 141         }
 142
 143         return (0); /* "num" is returned on Linux. */
 144 }
 145
 146 static int
 147 radeon_atom_hw_i2c_probe(device_t dev)
 148 {
 149
 150         return (BUS_PROBE_SPECIFIC);
 151 }
 152
 153 static int
 154 radeon_atom_hw_i2c_attach(device_t dev)
 155 {
 156         struct radeon_i2c_chan *i2c;
 157         device_t iic_dev;
 158
 159         i2c = device_get_softc(dev);
 160         device_set_desc(dev, i2c->name);
 161
 162         /* add generic bit-banging code */
 163         iic_dev = device_add_child(dev, "iicbus", -1);
 164         if (iic_dev == NULL)
 165                 return (ENXIO);
 166         device_quiet(iic_dev);
 167
 168         /* attach and probe added child */
 169         bus_generic_attach(dev);
 170
 171         return (0);
 172 }
 173
 174 static int
 175 radeon_atom_hw_i2c_detach(device_t dev)
 176 {
 177         /* detach bit-banding code. */
 178         bus_generic_detach(dev);
 179
 180         /* delete bit-banding code. */
 181         device_delete_children(dev);
 182         return (0);
 183 }
 184
 185 static int
 186 radeon_atom_hw_i2c_reset(device_t dev, u_char speed,
 187     u_char addr, u_char *oldaddr)
 188 {
 189
 190         return (0);
 191 }
 192
 193 static device_method_t radeon_atom_hw_i2c_methods[] = {
 194         DEVMETHOD(device_probe,         radeon_atom_hw_i2c_probe),
 195         DEVMETHOD(device_attach,        radeon_atom_hw_i2c_attach),
 196         DEVMETHOD(device_detach,        radeon_atom_hw_i2c_detach),
 197         DEVMETHOD(iicbus_reset,         radeon_atom_hw_i2c_reset),
 198         DEVMETHOD(iicbus_transfer,      radeon_atom_hw_i2c_xfer),
 199         DEVMETHOD_END
 200 };
 201
 202 static driver_t radeon_atom_hw_i2c_driver = {
 203         "radeon_atom_hw_i2c",
 204         radeon_atom_hw_i2c_methods,
 205         0
 206 };
 207
 208 static devclass_t radeon_atom_hw_i2c_devclass;
 209 DRIVER_MODULE_ORDERED(radeon_atom_hw_i2c, drmn, radeon_atom_hw_i2c_driver,
 210     radeon_atom_hw_i2c_devclass, 0, 0, SI_ORDER_ANY);