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/init.h>
  27
  28 #include <asm/io.h>
  29
  30 #include "cx88.h"
  31 #include "cx88-vp3054-i2c.h"
  32
  33 MODULE_DESCRIPTION("driver for cx2388x VP3054 design");
  34 MODULE_AUTHOR("Chris Pascoe <c.pascoe@itee.uq.edu.au>");
  35 MODULE_LICENSE("GPL");
  36
  37 /* ----------------------------------------------------------------------- */
  38
  39 static void vp3054_bit_setscl(void *data, int state)
  40 {
  41         struct cx8802_dev *dev = data;
  42         struct cx88_core *core = dev->core;
  43         struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
  44
  45         if (state) {
  46                 vp3054_i2c->state |=  0x0001;   /* SCL high */
  47                 vp3054_i2c->state &= ~0x0100;   /* external pullup */
  48         } else {
  49                 vp3054_i2c->state &= ~0x0001;   /* SCL low */
  50                 vp3054_i2c->state |=  0x0100;   /* drive pin */
  51         }
  52         cx_write(MO_GP0_IO, 0x010000 | vp3054_i2c->state);
  53         cx_read(MO_GP0_IO);
  54 }
  55
  56 static void vp3054_bit_setsda(void *data, int state)
  57 {
  58         struct cx8802_dev *dev = data;
  59         struct cx88_core *core = dev->core;
  60         struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
  61
  62         if (state) {
  63                 vp3054_i2c->state |=  0x0002;   /* SDA high */
  64                 vp3054_i2c->state &= ~0x0200;   /* tristate pin */
  65         } else {
  66                 vp3054_i2c->state &= ~0x0002;   /* SDA low */
  67                 vp3054_i2c->state |=  0x0200;   /* drive pin */
  68         }
  69         cx_write(MO_GP0_IO, 0x020000 | vp3054_i2c->state);
  70         cx_read(MO_GP0_IO);
  71 }
  72
  73 static int vp3054_bit_getscl(void *data)
  74 {
  75         struct cx8802_dev *dev = data;
  76         struct cx88_core *core = dev->core;
  77         u32 state;
  78
  79         state = cx_read(MO_GP0_IO);
  80         return (state & 0x01) ? 1 : 0;
  81 }
  82
  83 static int vp3054_bit_getsda(void *data)
  84 {
  85         struct cx8802_dev *dev = data;
  86         struct cx88_core *core = dev->core;
  87         u32 state;
  88
  89         state = cx_read(MO_GP0_IO);
  90         return (state & 0x02) ? 1 : 0;
  91 }
  92
  93 /* ----------------------------------------------------------------------- */
  94
  95 static const struct i2c_algo_bit_data vp3054_i2c_algo_template = {
  96         .setsda  = vp3054_bit_setsda,
  97         .setscl  = vp3054_bit_setscl,
  98         .getsda  = vp3054_bit_getsda,
  99         .getscl  = vp3054_bit_getscl,
 100         .udelay  = 16,
 101         .timeout = 200,
 102 };
 103
 104 /* ----------------------------------------------------------------------- */
 105
 106 int vp3054_i2c_probe(struct cx8802_dev *dev)
 107 {
 108         struct cx88_core *core = dev->core;
 109         struct vp3054_i2c_state *vp3054_i2c;
 110         int rc;
 111
 112         if (core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
 113                 return 0;
 114
 115         vp3054_i2c = kzalloc(sizeof(*vp3054_i2c), GFP_KERNEL);
 116         if (vp3054_i2c == NULL)
 117                 return -ENOMEM;
 118         dev->vp3054 = vp3054_i2c;
 119
 120         memcpy(&vp3054_i2c->algo, &vp3054_i2c_algo_template,
 121                sizeof(vp3054_i2c->algo));
 122
 123         vp3054_i2c->adap.class |= I2C_CLASS_TV_DIGITAL;
 124
 125         vp3054_i2c->adap.dev.parent = &dev->pci->dev;
 126         strlcpy(vp3054_i2c->adap.name, core->name,
 127                 sizeof(vp3054_i2c->adap.name));
 128         vp3054_i2c->adap.owner = THIS_MODULE;
 129         vp3054_i2c->adap.id = I2C_HW_B_CX2388x;
 130         vp3054_i2c->algo.data = dev;
 131         i2c_set_adapdata(&vp3054_i2c->adap, dev);
 132         vp3054_i2c->adap.algo_data = &vp3054_i2c->algo;
 133
 134         vp3054_bit_setscl(dev,1);
 135         vp3054_bit_setsda(dev,1);
 136
 137         rc = i2c_bit_add_bus(&vp3054_i2c->adap);
 138         if (0 != rc) {
 139                 printk("%s: vp3054_i2c register FAILED\n", core->name);
 140
 141                 kfree(dev->vp3054);
 142                 dev->vp3054 = NULL;
 143         }
 144
 145         return rc;
 146 }
 147
 148 void vp3054_i2c_remove(struct cx8802_dev *dev)
 149 {
 150         struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
 151
 152         if (vp3054_i2c == NULL ||
 153             dev->core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
 154                 return;
 155
 156         i2c_del_adapter(&vp3054_i2c->adap);
 157         kfree(vp3054_i2c);
 158 }
 159
 160 EXPORT_SYMBOL(vp3054_i2c_probe);
 161 EXPORT_SYMBOL(vp3054_i2c_remove);