1/*
2 *  Driver for the NXP SAA7164 PCIe bridge
3 *
4 *  Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com>
5 *
6 *  This program is free software; you can redistribute it and/or modify
7 *  it under the terms of the GNU General Public License as published by
8 *  the Free Software Foundation; either version 2 of the License, or
9 *  (at your option) any later version.
10 *
11 *  This program is distributed in the hope that it will be useful,
12 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 *
15 *  GNU General Public License for more details.
16 *
17 *  You should have received a copy of the GNU General Public License
18 *  along with this program; if not, write to the Free Software
19 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20 */
21
22#include <linux/module.h>
23#include <linux/moduleparam.h>
24#include <linux/init.h>
25#include <linux/delay.h>
26#include <linux/io.h>
27
28#include "saa7164.h"
29
30static int i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
31{
32	struct saa7164_i2c *bus = i2c_adap->algo_data;
33	struct saa7164_dev *dev = bus->dev;
34	int i, retval = 0;
35
36	dprintk(DBGLVL_I2C, "%s(num = %d)\n", __func__, num);
37
38	for (i = 0 ; i < num; i++) {
39		dprintk(DBGLVL_I2C, "%s(num = %d) addr = 0x%02x  len = 0x%x\n",
40			__func__, num, msgs[i].addr, msgs[i].len);
41		if (msgs[i].flags & I2C_M_RD) {
42			retval = saa7164_api_i2c_read(bus,
43				msgs[i].addr,
44				0 /* reglen */,
45				NULL /* reg */, msgs[i].len, msgs[i].buf);
46		} else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
47			   msgs[i].addr == msgs[i + 1].addr) {
48			/* write then read from same address */
49
50			retval = saa7164_api_i2c_read(bus, msgs[i].addr,
51				msgs[i].len, msgs[i].buf,
52				msgs[i+1].len, msgs[i+1].buf
53				);
54
55			i++;
56
57			if (retval < 0)
58				goto err;
59		} else {
60			/* write */
61			retval = saa7164_api_i2c_write(bus, msgs[i].addr,
62				msgs[i].len, msgs[i].buf);
63		}
64		if (retval < 0)
65			goto err;
66	}
67	return num;
68
69err:
70	return retval;
71}
72
73static u32 saa7164_functionality(struct i2c_adapter *adap)
74{
75	return I2C_FUNC_I2C;
76}
77
78static struct i2c_algorithm saa7164_i2c_algo_template = {
79	.master_xfer	= i2c_xfer,
80	.functionality	= saa7164_functionality,
81};
82
83/* ----------------------------------------------------------------------- */
84
85static struct i2c_adapter saa7164_i2c_adap_template = {
86	.name              = "saa7164",
87	.owner             = THIS_MODULE,
88	.algo              = &saa7164_i2c_algo_template,
89};
90
91static struct i2c_client saa7164_i2c_client_template = {
92	.name	= "saa7164 internal",
93};
94
95int saa7164_i2c_register(struct saa7164_i2c *bus)
96{
97	struct saa7164_dev *dev = bus->dev;
98
99	dprintk(DBGLVL_I2C, "%s(bus = %d)\n", __func__, bus->nr);
100
101	bus->i2c_adap = saa7164_i2c_adap_template;
102	bus->i2c_client = saa7164_i2c_client_template;
103
104	bus->i2c_adap.dev.parent = &dev->pci->dev;
105
106	strlcpy(bus->i2c_adap.name, bus->dev->name,
107		sizeof(bus->i2c_adap.name));
108
109	bus->i2c_adap.algo_data = bus;
110	i2c_set_adapdata(&bus->i2c_adap, bus);
111	i2c_add_adapter(&bus->i2c_adap);
112
113	bus->i2c_client.adapter = &bus->i2c_adap;
114
115	if (0 != bus->i2c_rc)
116		printk(KERN_ERR "%s: i2c bus %d register FAILED\n",
117			dev->name, bus->nr);
118
119	return bus->i2c_rc;
120}
121
122int saa7164_i2c_unregister(struct saa7164_i2c *bus)
123{
124	i2c_del_adapter(&bus->i2c_adap);
125	return 0;
126}
127