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
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/delay.h>
  14 #include <linux/slab.h>
  15 #include <linux/poll.h>
  16 #include <linux/io.h>
  17 #include <linux/pci.h>
  18 #include <linux/pci_ids.h>
  19 #include <linux/timer.h>
  20 #include <linux/i2c.h>
  21 #include <linux/swab.h>
  22 #include <linux/vmalloc.h>
  23
  24 #include "ddbridge.h"
  25 #include "ddbridge-i2c.h"
  26 #include "ddbridge-regs.h"
  27 #include "ddbridge-io.h"
  28
  29 /******************************************************************************/
  30
  31 static int ddb_i2c_cmd(struct ddb_i2c *i2c, u32 adr, u32 cmd)
  32 {
  33         struct ddb *dev = i2c->dev;
  34         unsigned long stat;
  35         u32 val;
  36
  37         ddbwritel(dev, (adr << 9) | cmd, i2c->regs + I2C_COMMAND);
  38         stat = wait_for_completion_timeout(&i2c->completion, HZ);
  39         val = ddbreadl(dev, i2c->regs + I2C_COMMAND);
  40         if (stat == 0) {
  41                 dev_err(dev->dev, "I2C timeout, card %d, port %d, link %u\n",
  42                         dev->nr, i2c->nr, i2c->link);
  43                 {
  44                         u32 istat = ddbreadl(dev, INTERRUPT_STATUS);
  45
  46                         dev_err(dev->dev, "DDBridge IRS %08x\n", istat);
  47                         if (i2c->link) {
  48                                 u32 listat = ddbreadl(dev,
  49                                         DDB_LINK_TAG(i2c->link) |
  50                                         INTERRUPT_STATUS);
  51
  52                                 dev_err(dev->dev, "DDBridge link %u IRS %08x\n",
  53                                         i2c->link, listat);
  54                         }
  55                         if (istat & 1) {
  56                                 ddbwritel(dev, istat & 1, INTERRUPT_ACK);
  57                         } else {
  58                                 u32 mon = ddbreadl(dev,
  59                                         i2c->regs + I2C_MONITOR);
  60
  61                                 dev_err(dev->dev, "I2C cmd=%08x mon=%08x\n",
  62                                         val, mon);
  63                         }
  64                 }
  65                 return -EIO;
  66         }
  67         val &= 0x70000;
  68         if (val == 0x20000)
  69                 dev_err(dev->dev, "I2C bus error\n");
  70         if (val)
  71                 return -EIO;
  72         return 0;
  73 }
  74
  75 static int ddb_i2c_master_xfer(struct i2c_adapter *adapter,
  76                                struct i2c_msg msg[], int num)
  77 {
  78         struct ddb_i2c *i2c = (struct ddb_i2c *)i2c_get_adapdata(adapter);
  79         struct ddb *dev = i2c->dev;
  80         u8 addr = 0;
  81
  82         addr = msg[0].addr;
  83         if (msg[0].len > i2c->bsize)
  84                 return -EIO;
  85         switch (num) {
  86         case 1:
  87                 if (msg[0].flags & I2C_M_RD) {
  88                         ddbwritel(dev, msg[0].len << 16,
  89                                   i2c->regs + I2C_TASKLENGTH);
  90                         if (ddb_i2c_cmd(i2c, addr, 3))
  91                                 break;
  92                         ddbcpyfrom(dev, msg[0].buf,
  93                                    i2c->rbuf, msg[0].len);
  94                         return num;
  95                 }
  96                 ddbcpyto(dev, i2c->wbuf, msg[0].buf, msg[0].len);
  97                 ddbwritel(dev, msg[0].len, i2c->regs + I2C_TASKLENGTH);
  98                 if (ddb_i2c_cmd(i2c, addr, 2))
  99                         break;
 100                 return num;
 101         case 2:
 102                 if ((msg[0].flags & I2C_M_RD) == I2C_M_RD)
 103                         break;
 104                 if ((msg[1].flags & I2C_M_RD) != I2C_M_RD)
 105                         break;
 106                 if (msg[1].len > i2c->bsize)
 107                         break;
 108                 ddbcpyto(dev, i2c->wbuf, msg[0].buf, msg[0].len);
 109                 ddbwritel(dev, msg[0].len | (msg[1].len << 16),
 110                           i2c->regs + I2C_TASKLENGTH);
 111                 if (ddb_i2c_cmd(i2c, addr, 1))
 112                         break;
 113                 ddbcpyfrom(dev, msg[1].buf,
 114                            i2c->rbuf,
 115                            msg[1].len);
 116                 return num;
 117         default:
 118                 break;
 119         }
 120         return -EIO;
 121 }
 122
 123 static u32 ddb_i2c_functionality(struct i2c_adapter *adap)
 124 {
 125         return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 126 }
 127
 128 static const struct i2c_algorithm ddb_i2c_algo = {
 129         .master_xfer   = ddb_i2c_master_xfer,
 130         .functionality = ddb_i2c_functionality,
 131 };
 132
 133 void ddb_i2c_release(struct ddb *dev)
 134 {
 135         int i;
 136         struct ddb_i2c *i2c;
 137
 138         for (i = 0; i < dev->i2c_num; i++) {
 139                 i2c = &dev->i2c[i];
 140                 i2c_del_adapter(&i2c->adap);
 141         }
 142 }
 143
 144 static void i2c_handler(void *priv)
 145 {
 146         struct ddb_i2c *i2c = (struct ddb_i2c *)priv;
 147
 148         complete(&i2c->completion);
 149 }
 150
 151 static int ddb_i2c_add(struct ddb *dev, struct ddb_i2c *i2c,
 152                        const struct ddb_regmap *regmap, int link,
 153                        int i, int num)
 154 {
 155         struct i2c_adapter *adap;
 156
 157         i2c->nr = i;
 158         i2c->dev = dev;
 159         i2c->link = link;
 160         i2c->bsize = regmap->i2c_buf->size;
 161         i2c->wbuf = DDB_LINK_TAG(link) |
 162                 (regmap->i2c_buf->base + i2c->bsize * i);
 163         i2c->rbuf = i2c->wbuf; /* + i2c->bsize / 2 */
 164         i2c->regs = DDB_LINK_TAG(link) |
 165                 (regmap->i2c->base + regmap->i2c->size * i);
 166         ddbwritel(dev, I2C_SPEED_100, i2c->regs + I2C_TIMING);
 167         ddbwritel(dev, ((i2c->rbuf & 0xffff) << 16) | (i2c->wbuf & 0xffff),
 168                   i2c->regs + I2C_TASKADDRESS);
 169         init_completion(&i2c->completion);
 170
 171         adap = &i2c->adap;
 172         i2c_set_adapdata(adap, i2c);
 173 #ifdef I2C_ADAP_CLASS_TV_DIGITAL
 174         adap->class = I2C_ADAP_CLASS_TV_DIGITAL | I2C_CLASS_TV_ANALOG;
 175 #else
 176 #ifdef I2C_CLASS_TV_ANALOG
 177         adap->class = I2C_CLASS_TV_ANALOG;
 178 #endif
 179 #endif
 180         snprintf(adap->name, I2C_NAME_SIZE, "ddbridge_%02x.%x.%x",
 181                  dev->nr, i2c->link, i);
 182         adap->algo = &ddb_i2c_algo;
 183         adap->algo_data = (void *)i2c;
 184         adap->dev.parent = dev->dev;
 185         return i2c_add_adapter(adap);
 186 }
 187
 188 int ddb_i2c_init(struct ddb *dev)
 189 {
 190         int stat = 0;
 191         u32 i, j, num = 0, l, base;
 192         struct ddb_i2c *i2c;
 193         struct i2c_adapter *adap;
 194         const struct ddb_regmap *regmap;
 195
 196         for (l = 0; l < DDB_MAX_LINK; l++) {
 197                 if (!dev->link[l].info)
 198                         continue;
 199                 regmap = dev->link[l].info->regmap;
 200                 if (!regmap || !regmap->i2c)
 201                         continue;
 202                 base = regmap->irq_base_i2c;
 203                 for (i = 0; i < regmap->i2c->num; i++) {
 204                         if (!(dev->link[l].info->i2c_mask & (1 << i)))
 205                                 continue;
 206                         i2c = &dev->i2c[num];
 207                         ddb_irq_set(dev, l, i + base, i2c_handler, i2c);
 208                         stat = ddb_i2c_add(dev, i2c, regmap, l, i, num);
 209                         if (stat)
 210                                 break;
 211                         num++;
 212                 }
 213         }
 214         if (stat) {
 215                 for (j = 0; j < num; j++) {
 216                         i2c = &dev->i2c[j];
 217                         adap = &i2c->adap;
 218                         i2c_del_adapter(adap);
 219                 }
 220         } else {
 221                 dev->i2c_num = num;
 222         }
 223
 224         return stat;
 225 }