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

   1/*
   2
   3    cx88-vp3054-i2c.c  --  support for the secondary I2C bus of the
   4                           DNTV Live! DVB-T Pro (VP-3054), wired as:
   5                           GPIO[0] -> SCL, GPIO[1] -> SDA
   6
   7    (c) 2005 Chris Pascoe <c.pascoe@itee.uq.edu.au>
   8
   9    This program is free software; you can redistribute it and/or modify
  10    it under the terms of the GNU General Public License as published by
  11    the Free Software Foundation; either version 2 of the License, or
  12    (at your option) any later version.
  13
  14    This program is distributed in the hope that it will be useful,
  15    but WITHOUT ANY WARRANTY; without even the implied warranty of
  16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17    GNU General Public License for more details.
  18
  19    You should have received a copy of the GNU General Public License
  20    along with this program; if not, write to the Free Software
  21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  22
  23*/
  24
  25#include <linux/module.h>
  26#include <linux/slab.h>
  27#include <linux/init.h>
  28
  29#include <asm/io.h>
  30
  31#include "cx88.h"
  32#include "cx88-vp3054-i2c.h"
  33
  34MODULE_DESCRIPTION("driver for cx2388x VP3054 design");
  35MODULE_AUTHOR("Chris Pascoe <c.pascoe@itee.uq.edu.au>");
  36MODULE_LICENSE("GPL");
  37
  38/* ----------------------------------------------------------------------- */
  39
  40static void vp3054_bit_setscl(void *data, int state)
  41{
  42        struct cx8802_dev *dev = data;
  43        struct cx88_core *core = dev->core;
  44        struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
  45
  46        if (state) {
  47                vp3054_i2c->state |=  0x0001;   /* SCL high */
  48                vp3054_i2c->state &= ~0x0100;   /* external pullup */
  49        } else {
  50                vp3054_i2c->state &= ~0x0001;   /* SCL low */
  51                vp3054_i2c->state |=  0x0100;   /* drive pin */
  52        }
  53        cx_write(MO_GP0_IO, 0x010000 | vp3054_i2c->state);
  54        cx_read(MO_GP0_IO);
  55}
  56
  57static void vp3054_bit_setsda(void *data, int state)
  58{
  59        struct cx8802_dev *dev = data;
  60        struct cx88_core *core = dev->core;
  61        struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
  62
  63        if (state) {
  64                vp3054_i2c->state |=  0x0002;   /* SDA high */
  65                vp3054_i2c->state &= ~0x0200;   /* tristate pin */
  66        } else {
  67                vp3054_i2c->state &= ~0x0002;   /* SDA low */
  68                vp3054_i2c->state |=  0x0200;   /* drive pin */
  69        }
  70        cx_write(MO_GP0_IO, 0x020000 | vp3054_i2c->state);
  71        cx_read(MO_GP0_IO);
  72}
  73
  74static int vp3054_bit_getscl(void *data)
  75{
  76        struct cx8802_dev *dev = data;
  77        struct cx88_core *core = dev->core;
  78        u32 state;
  79
  80        state = cx_read(MO_GP0_IO);
  81        return (state & 0x01) ? 1 : 0;
  82}
  83
  84static int vp3054_bit_getsda(void *data)
  85{
  86        struct cx8802_dev *dev = data;
  87        struct cx88_core *core = dev->core;
  88        u32 state;
  89
  90        state = cx_read(MO_GP0_IO);
  91        return (state & 0x02) ? 1 : 0;
  92}
  93
  94/* ----------------------------------------------------------------------- */
  95
  96static const struct i2c_algo_bit_data vp3054_i2c_algo_template = {
  97        .setsda  = vp3054_bit_setsda,
  98        .setscl  = vp3054_bit_setscl,
  99        .getsda  = vp3054_bit_getsda,
 100        .getscl  = vp3054_bit_getscl,
 101        .udelay  = 16,
 102        .timeout = 200,
 103};
 104
 105/* ----------------------------------------------------------------------- */
 106
 107int vp3054_i2c_probe(struct cx8802_dev *dev)
 108{
 109        struct cx88_core *core = dev->core;
 110        struct vp3054_i2c_state *vp3054_i2c;
 111        int rc;
 112
 113        if (core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
 114                return 0;
 115
 116        vp3054_i2c = kzalloc(sizeof(*vp3054_i2c), GFP_KERNEL);
 117        if (vp3054_i2c == NULL)
 118                return -ENOMEM;
 119        dev->vp3054 = vp3054_i2c;
 120
 121        memcpy(&vp3054_i2c->algo, &vp3054_i2c_algo_template,
 122               sizeof(vp3054_i2c->algo));
 123
 124        vp3054_i2c->adap.dev.parent = &dev->pci->dev;
 125        strlcpy(vp3054_i2c->adap.name, core->name,
 126                sizeof(vp3054_i2c->adap.name));
 127        vp3054_i2c->adap.owner = THIS_MODULE;
 128        vp3054_i2c->algo.data = dev;
 129        i2c_set_adapdata(&vp3054_i2c->adap, dev);
 130        vp3054_i2c->adap.algo_data = &vp3054_i2c->algo;
 131
 132        vp3054_bit_setscl(dev,1);
 133        vp3054_bit_setsda(dev,1);
 134
 135        rc = i2c_bit_add_bus(&vp3054_i2c->adap);
 136        if (0 != rc) {
 137                printk("%s: vp3054_i2c register FAILED\n", core->name);
 138
 139                kfree(dev->vp3054);
 140                dev->vp3054 = NULL;
 141        }
 142
 143        return rc;
 144}
 145
 146void vp3054_i2c_remove(struct cx8802_dev *dev)
 147{
 148        struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
 149
 150        if (vp3054_i2c == NULL ||
 151            dev->core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
 152                return;
 153
 154        i2c_del_adapter(&vp3054_i2c->adap);
 155        kfree(vp3054_i2c);
 156}
 157
 158EXPORT_SYMBOL(vp3054_i2c_probe);
 159EXPORT_SYMBOL(vp3054_i2c_remove);
 160