linux/drivers/media/pci/ddbridge/ddbridge-i2c.c
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   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
  40static 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
  84static 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
 132static u32 ddb_i2c_functionality(struct i2c_adapter *adap)
 133{
 134        return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 135}
 136
 137static const struct i2c_algorithm ddb_i2c_algo = {
 138        .master_xfer   = ddb_i2c_master_xfer,
 139        .functionality = ddb_i2c_functionality,
 140};
 141
 142void 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
 153static void i2c_handler(void *priv)
 154{
 155        struct ddb_i2c *i2c = (struct ddb_i2c *)priv;
 156
 157        complete(&i2c->completion);
 158}
 159
 160static 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
 197int 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}
 235