drivers/media/pci/ddbridge/ddbridge-i2c.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ddbridge-i2c.c: Digital Devices bridge i2c driver
   4  *
   5  * Copyright (C) 2010-2017 Digital Devices GmbH
   6  *                         Ralph Metzler <rjkm@metzlerbros.de>
   7  *                         Marcus Metzler <mocm@metzlerbros.de>
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License
  11  * version 2 only, as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/delay.h>
  23 #include <linux/slab.h>
  24 #include <linux/poll.h>
  25 #include <linux/io.h>
  26 #include <linux/pci.h>
  27 #include <linux/pci_ids.h>
  28 #include <linux/timer.h>
  29 #include <linux/i2c.h>
  30 #include <linux/swab.h>
  31 #include <linux/vmalloc.h>
  32
  33 #include "ddbridge.h"
  34 #include "ddbridge-i2c.h"
  35 #include "ddbridge-regs.h"
  36 #include "ddbridge-io.h"
  37
  38 /******************************************************************************/
  39
  40 static int ddb_i2c_cmd(struct ddb_i2c *i2c, u32 adr, u32 cmd)
  41 {
  42         struct ddb *dev = i2c->dev;
  43         unsigned long stat;
  44         u32 val;
  45
  46         ddbwritel(dev, (adr << 9) | cmd, i2c->regs + I2C_COMMAND);
  47         stat = wait_for_completion_timeout(&i2c->completion, HZ);
  48         val = ddbreadl(dev, i2c->regs + I2C_COMMAND);
  49         if (stat == 0) {
  50                 dev_err(dev->dev, "I2C timeout, card %d, port %d, link %u\n",
  51                         dev->nr, i2c->nr, i2c->link);
  52                 {
  53                         u32 istat = ddbreadl(dev, INTERRUPT_STATUS);
  54
  55                         dev_err(dev->dev, "DDBridge IRS %08x\n", istat);
  56                         if (i2c->link) {
  57                                 u32 listat = ddbreadl(dev,
  58                                         DDB_LINK_TAG(i2c->link) |
  59                                         INTERRUPT_STATUS);
  60
  61                                 dev_err(dev->dev, "DDBridge link %u IRS %08x\n",
  62                                         i2c->link, listat);
  63                         }
  64                         if (istat & 1) {
  65                                 ddbwritel(dev, istat & 1, INTERRUPT_ACK);
  66                         } else {
  67                                 u32 mon = ddbreadl(dev,
  68                                         i2c->regs + I2C_MONITOR);
  69
  70                                 dev_err(dev->dev, "I2C cmd=%08x mon=%08x\n",
  71                                         val, mon);
  72                         }
  73                 }
  74                 return -EIO;
  75         }
  76         val &= 0x70000;
  77         if (val == 0x20000)
  78                 dev_err(dev->dev, "I2C bus error\n");
  79         if (val)
  80                 return -EIO;
  81         return 0;
  82 }
  83
  84 static int ddb_i2c_master_xfer(struct i2c_adapter *adapter,
  85                                struct i2c_msg msg[], int num)
  86 {
  87         struct ddb_i2c *i2c = (struct ddb_i2c *)i2c_get_adapdata(adapter);
  88         struct ddb *dev = i2c->dev;
  89         u8 addr = 0;
  90
  91         addr = msg[0].addr;
  92         if (msg[0].len > i2c->bsize)
  93                 return -EIO;
  94         switch (num) {
  95         case 1:
  96                 if (msg[0].flags & I2C_M_RD) {
  97                         ddbwritel(dev, msg[0].len << 16,
  98                                   i2c->regs + I2C_TASKLENGTH);
  99                         if (ddb_i2c_cmd(i2c, addr, 3))
 100                                 break;
 101                         ddbcpyfrom(dev, msg[0].buf,
 102                                    i2c->rbuf, msg[0].len);
 103                         return num;
 104                 }
 105                 ddbcpyto(dev, i2c->wbuf, msg[0].buf, msg[0].len);
 106                 ddbwritel(dev, msg[0].len, i2c->regs + I2C_TASKLENGTH);
 107                 if (ddb_i2c_cmd(i2c, addr, 2))
 108                         break;
 109                 return num;
 110         case 2:
 111                 if ((msg[0].flags & I2C_M_RD) == I2C_M_RD)
 112                         break;
 113                 if ((msg[1].flags & I2C_M_RD) != I2C_M_RD)
 114                         break;
 115                 if (msg[1].len > i2c->bsize)
 116                         break;
 117                 ddbcpyto(dev, i2c->wbuf, msg[0].buf, msg[0].len);
 118                 ddbwritel(dev, msg[0].len | (msg[1].len << 16),
 119                           i2c->regs + I2C_TASKLENGTH);
 120                 if (ddb_i2c_cmd(i2c, addr, 1))
 121                         break;
 122                 ddbcpyfrom(dev, msg[1].buf,
 123                            i2c->rbuf,
 124                            msg[1].len);
 125                 return num;
 126         default:
 127                 break;
 128         }
 129         return -EIO;
 130 }
 131
 132 static u32 ddb_i2c_functionality(struct i2c_adapter *adap)
 133 {
 134         return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 135 }
 136
 137 static const struct i2c_algorithm ddb_i2c_algo = {
 138         .master_xfer   = ddb_i2c_master_xfer,
 139         .functionality = ddb_i2c_functionality,
 140 };
 141
 142 void ddb_i2c_release(struct ddb *dev)
 143 {
 144         int i;
 145         struct ddb_i2c *i2c;
 146
 147         for (i = 0; i < dev->i2c_num; i++) {
 148                 i2c = &dev->i2c[i];
 149                 i2c_del_adapter(&i2c->adap);
 150         }
 151 }
 152
 153 static void i2c_handler(void *priv)
 154 {
 155         struct ddb_i2c *i2c = (struct ddb_i2c *)priv;
 156
 157         complete(&i2c->completion);
 158 }
 159
 160 static int ddb_i2c_add(struct ddb *dev, struct ddb_i2c *i2c,
 161                        const struct ddb_regmap *regmap, int link,
 162                        int i, int num)
 163 {
 164         struct i2c_adapter *adap;
 165
 166         i2c->nr = i;
 167         i2c->dev = dev;
 168         i2c->link = link;
 169         i2c->bsize = regmap->i2c_buf->size;
 170         i2c->wbuf = DDB_LINK_TAG(link) |
 171                 (regmap->i2c_buf->base + i2c->bsize * i);
 172         i2c->rbuf = i2c->wbuf; /* + i2c->bsize / 2 */
 173         i2c->regs = DDB_LINK_TAG(link) |
 174                 (regmap->i2c->base + regmap->i2c->size * i);
 175         ddbwritel(dev, I2C_SPEED_100, i2c->regs + I2C_TIMING);
 176         ddbwritel(dev, ((i2c->rbuf & 0xffff) << 16) | (i2c->wbuf & 0xffff),
 177                   i2c->regs + I2C_TASKADDRESS);
 178         init_completion(&i2c->completion);
 179
 180         adap = &i2c->adap;
 181         i2c_set_adapdata(adap, i2c);
 182 #ifdef I2C_ADAP_CLASS_TV_DIGITAL
 183         adap->class = I2C_ADAP_CLASS_TV_DIGITAL | I2C_CLASS_TV_ANALOG;
 184 #else
 185 #ifdef I2C_CLASS_TV_ANALOG
 186         adap->class = I2C_CLASS_TV_ANALOG;
 187 #endif
 188 #endif
 189         snprintf(adap->name, I2C_NAME_SIZE, "ddbridge_%02x.%x.%x",
 190                  dev->nr, i2c->link, i);
 191         adap->algo = &ddb_i2c_algo;
 192         adap->algo_data = (void *)i2c;
 193         adap->dev.parent = dev->dev;
 194         return i2c_add_adapter(adap);
 195 }
 196
 197 int ddb_i2c_init(struct ddb *dev)
 198 {
 199         int stat = 0;
 200         u32 i, j, num = 0, l, base;
 201         struct ddb_i2c *i2c;
 202         struct i2c_adapter *adap;
 203         const struct ddb_regmap *regmap;
 204
 205         for (l = 0; l < DDB_MAX_LINK; l++) {
 206                 if (!dev->link[l].info)
 207                         continue;
 208                 regmap = dev->link[l].info->regmap;
 209                 if (!regmap || !regmap->i2c)
 210                         continue;
 211                 base = regmap->irq_base_i2c;
 212                 for (i = 0; i < regmap->i2c->num; i++) {
 213                         if (!(dev->link[l].info->i2c_mask & (1 << i)))
 214                                 continue;
 215                         i2c = &dev->i2c[num];
 216                         ddb_irq_set(dev, l, i + base, i2c_handler, i2c);
 217                         stat = ddb_i2c_add(dev, i2c, regmap, l, i, num);
 218                         if (stat)
 219                                 break;
 220                         num++;
 221                 }
 222         }
 223         if (stat) {
 224                 for (j = 0; j < num; j++) {
 225                         i2c = &dev->i2c[j];
 226                         adap = &i2c->adap;
 227                         i2c_del_adapter(adap);
 228                 }
 229         } else {
 230                 dev->i2c_num = num;
 231         }
 232
 233         return stat;
 234 }