LXR linux/drivers/media/pci/cx88/cx88-vp3054-i2c.c

   1/*
   2 * cx88-vp3054-i2c.c -- support for the secondary I2C bus of the
   3 *                      DNTV Live! DVB-T Pro (VP-3054), wired as:
   4 *                      GPIO[0] -> SCL, GPIO[1] -> SDA
   5 *
   6 * (c) 2005 Chris Pascoe <c.pascoe@itee.uq.edu.au>
   7 *
   8 * This program is free software; you can redistribute it and/or modify
   9 * it under the terms of the GNU General Public License as published by
  10 * the Free Software Foundation; either version 2 of the License, or
  11 * (at your option) any later version.
  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 "cx88.h"
  20#include "cx88-vp3054-i2c.h"
  21
  22#include <linux/module.h>
  23#include <linux/slab.h>
  24#include <linux/init.h>
  25#include <linux/io.h>
  26
  27MODULE_DESCRIPTION("driver for cx2388x VP3054 design");
  28MODULE_AUTHOR("Chris Pascoe <c.pascoe@itee.uq.edu.au>");
  29MODULE_LICENSE("GPL");
  30
  31/* ----------------------------------------------------------------------- */
  32
  33static void vp3054_bit_setscl(void *data, int state)
  34{
  35        struct cx8802_dev *dev = data;
  36        struct cx88_core *core = dev->core;
  37        struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
  38
  39        if (state) {
  40                vp3054_i2c->state |=  0x0001;   /* SCL high */
  41                vp3054_i2c->state &= ~0x0100;   /* external pullup */
  42        } else {
  43                vp3054_i2c->state &= ~0x0001;   /* SCL low */
  44                vp3054_i2c->state |=  0x0100;   /* drive pin */
  45        }
  46        cx_write(MO_GP0_IO, 0x010000 | vp3054_i2c->state);
  47        cx_read(MO_GP0_IO);
  48}
  49
  50static void vp3054_bit_setsda(void *data, int state)
  51{
  52        struct cx8802_dev *dev = data;
  53        struct cx88_core *core = dev->core;
  54        struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
  55
  56        if (state) {
  57                vp3054_i2c->state |=  0x0002;   /* SDA high */
  58                vp3054_i2c->state &= ~0x0200;   /* tristate pin */
  59        } else {
  60                vp3054_i2c->state &= ~0x0002;   /* SDA low */
  61                vp3054_i2c->state |=  0x0200;   /* drive pin */
  62        }
  63        cx_write(MO_GP0_IO, 0x020000 | vp3054_i2c->state);
  64        cx_read(MO_GP0_IO);
  65}
  66
  67static int vp3054_bit_getscl(void *data)
  68{
  69        struct cx8802_dev *dev = data;
  70        struct cx88_core *core = dev->core;
  71        u32 state;
  72
  73        state = cx_read(MO_GP0_IO);
  74        return (state & 0x01) ? 1 : 0;
  75}
  76
  77static int vp3054_bit_getsda(void *data)
  78{
  79        struct cx8802_dev *dev = data;
  80        struct cx88_core *core = dev->core;
  81        u32 state;
  82
  83        state = cx_read(MO_GP0_IO);
  84        return (state & 0x02) ? 1 : 0;
  85}
  86
  87/* ----------------------------------------------------------------------- */
  88
  89static const struct i2c_algo_bit_data vp3054_i2c_algo_template = {
  90        .setsda  = vp3054_bit_setsda,
  91        .setscl  = vp3054_bit_setscl,
  92        .getsda  = vp3054_bit_getsda,
  93        .getscl  = vp3054_bit_getscl,
  94        .udelay  = 16,
  95        .timeout = 200,
  96};
  97
  98/* ----------------------------------------------------------------------- */
  99
 100int vp3054_i2c_probe(struct cx8802_dev *dev)
 101{
 102        struct cx88_core *core = dev->core;
 103        struct vp3054_i2c_state *vp3054_i2c;
 104        int rc;
 105
 106        if (core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
 107                return 0;
 108
 109        vp3054_i2c = kzalloc(sizeof(*vp3054_i2c), GFP_KERNEL);
 110        if (!vp3054_i2c)
 111                return -ENOMEM;
 112        dev->vp3054 = vp3054_i2c;
 113
 114        vp3054_i2c->algo = vp3054_i2c_algo_template;
 115
 116        vp3054_i2c->adap.dev.parent = &dev->pci->dev;
 117        strlcpy(vp3054_i2c->adap.name, core->name,
 118                sizeof(vp3054_i2c->adap.name));
 119        vp3054_i2c->adap.owner = THIS_MODULE;
 120        vp3054_i2c->algo.data = dev;
 121        i2c_set_adapdata(&vp3054_i2c->adap, dev);
 122        vp3054_i2c->adap.algo_data = &vp3054_i2c->algo;
 123
 124        vp3054_bit_setscl(dev, 1);
 125        vp3054_bit_setsda(dev, 1);
 126
 127        rc = i2c_bit_add_bus(&vp3054_i2c->adap);
 128        if (rc != 0) {
 129                pr_err("vp3054_i2c register FAILED\n");
 130
 131                kfree(dev->vp3054);
 132                dev->vp3054 = NULL;
 133        }
 134
 135        return rc;
 136}
 137EXPORT_SYMBOL(vp3054_i2c_probe);
 138
 139void vp3054_i2c_remove(struct cx8802_dev *dev)
 140{
 141        struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
 142
 143        if (!vp3054_i2c ||
 144            dev->core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
 145                return;
 146
 147        i2c_del_adapter(&vp3054_i2c->adap);
 148        kfree(vp3054_i2c);
 149}
 150EXPORT_SYMBOL(vp3054_i2c_remove);
 151