1 // SPDX-License-Identifier: GPL-2.0-or-later
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 
10 #include "cx88.h"
11 #include "cx88-vp3054-i2c.h"
12 
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/init.h>
16 #include <linux/io.h>
17 
18 MODULE_DESCRIPTION("driver for cx2388x VP3054 design");
19 MODULE_AUTHOR("Chris Pascoe <c.pascoe@itee.uq.edu.au>");
20 MODULE_LICENSE("GPL");
21 
22 /* ----------------------------------------------------------------------- */
23 
24 static void vp3054_bit_setscl(void *data, int state)
25 {
26 	struct cx8802_dev *dev = data;
27 	struct cx88_core *core = dev->core;
28 	struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
29 
30 	if (state) {
31 		vp3054_i2c->state |=  0x0001;	/* SCL high */
32 		vp3054_i2c->state &= ~0x0100;	/* external pullup */
33 	} else {
34 		vp3054_i2c->state &= ~0x0001;	/* SCL low */
35 		vp3054_i2c->state |=  0x0100;	/* drive pin */
36 	}
37 	cx_write(MO_GP0_IO, 0x010000 | vp3054_i2c->state);
38 	cx_read(MO_GP0_IO);
39 }
40 
41 static void vp3054_bit_setsda(void *data, int state)
42 {
43 	struct cx8802_dev *dev = data;
44 	struct cx88_core *core = dev->core;
45 	struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
46 
47 	if (state) {
48 		vp3054_i2c->state |=  0x0002;	/* SDA high */
49 		vp3054_i2c->state &= ~0x0200;	/* tristate pin */
50 	} else {
51 		vp3054_i2c->state &= ~0x0002;	/* SDA low */
52 		vp3054_i2c->state |=  0x0200;	/* drive pin */
53 	}
54 	cx_write(MO_GP0_IO, 0x020000 | vp3054_i2c->state);
55 	cx_read(MO_GP0_IO);
56 }
57 
58 static int vp3054_bit_getscl(void *data)
59 {
60 	struct cx8802_dev *dev = data;
61 	struct cx88_core *core = dev->core;
62 	u32 state;
63 
64 	state = cx_read(MO_GP0_IO);
65 	return (state & 0x01) ? 1 : 0;
66 }
67 
68 static int vp3054_bit_getsda(void *data)
69 {
70 	struct cx8802_dev *dev = data;
71 	struct cx88_core *core = dev->core;
72 	u32 state;
73 
74 	state = cx_read(MO_GP0_IO);
75 	return (state & 0x02) ? 1 : 0;
76 }
77 
78 /* ----------------------------------------------------------------------- */
79 
80 static const struct i2c_algo_bit_data vp3054_i2c_algo_template = {
81 	.setsda  = vp3054_bit_setsda,
82 	.setscl  = vp3054_bit_setscl,
83 	.getsda  = vp3054_bit_getsda,
84 	.getscl  = vp3054_bit_getscl,
85 	.udelay  = 16,
86 	.timeout = 200,
87 };
88 
89 /* ----------------------------------------------------------------------- */
90 
91 int vp3054_i2c_probe(struct cx8802_dev *dev)
92 {
93 	struct cx88_core *core = dev->core;
94 	struct vp3054_i2c_state *vp3054_i2c;
95 	int rc;
96 
97 	if (core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
98 		return 0;
99 
100 	vp3054_i2c = kzalloc(sizeof(*vp3054_i2c), GFP_KERNEL);
101 	if (!vp3054_i2c)
102 		return -ENOMEM;
103 	dev->vp3054 = vp3054_i2c;
104 
105 	vp3054_i2c->algo = vp3054_i2c_algo_template;
106 
107 	vp3054_i2c->adap.dev.parent = &dev->pci->dev;
108 	strscpy(vp3054_i2c->adap.name, core->name,
109 		sizeof(vp3054_i2c->adap.name));
110 	vp3054_i2c->adap.owner = THIS_MODULE;
111 	vp3054_i2c->algo.data = dev;
112 	i2c_set_adapdata(&vp3054_i2c->adap, dev);
113 	vp3054_i2c->adap.algo_data = &vp3054_i2c->algo;
114 
115 	vp3054_bit_setscl(dev, 1);
116 	vp3054_bit_setsda(dev, 1);
117 
118 	rc = i2c_bit_add_bus(&vp3054_i2c->adap);
119 	if (rc != 0) {
120 		pr_err("vp3054_i2c register FAILED\n");
121 
122 		kfree(dev->vp3054);
123 		dev->vp3054 = NULL;
124 	}
125 
126 	return rc;
127 }
128 EXPORT_SYMBOL(vp3054_i2c_probe);
129 
130 void vp3054_i2c_remove(struct cx8802_dev *dev)
131 {
132 	struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
133 
134 	if (!vp3054_i2c ||
135 	    dev->core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
136 		return;
137 
138 	i2c_del_adapter(&vp3054_i2c->adap);
139 	kfree(vp3054_i2c);
140 }
141 EXPORT_SYMBOL(vp3054_i2c_remove);
142