V4L/DVB (11568): cx18: Fix the handling of i2c bus registration error
[linux-2.6] / 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);