1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Driver for the NXP SAA7164 PCIe bridge
4 *
5 * Copyright (c) 2010-2015 Steven Toth <stoth@kernellabs.com>
6 */
7
8 #include <linux/module.h>
9 #include <linux/moduleparam.h>
10 #include <linux/init.h>
11 #include <linux/delay.h>
12 #include <linux/io.h>
13
14 #include "saa7164.h"
15
i2c_xfer(struct i2c_adapter * i2c_adap,struct i2c_msg * msgs,int num)16 static int i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
17 {
18 struct saa7164_i2c *bus = i2c_adap->algo_data;
19 struct saa7164_dev *dev = bus->dev;
20 int i, retval = 0;
21
22 dprintk(DBGLVL_I2C, "%s(num = %d)\n", __func__, num);
23
24 for (i = 0 ; i < num; i++) {
25 dprintk(DBGLVL_I2C, "%s(num = %d) addr = 0x%02x len = 0x%x\n",
26 __func__, num, msgs[i].addr, msgs[i].len);
27 if (msgs[i].flags & I2C_M_RD) {
28 retval = saa7164_api_i2c_read(bus,
29 msgs[i].addr,
30 0 /* reglen */,
31 NULL /* reg */, msgs[i].len, msgs[i].buf);
32 } else if (i + 1 < num && (msgs[i + 1].flags & I2C_M_RD) &&
33 msgs[i].addr == msgs[i + 1].addr) {
34 /* write then read from same address */
35
36 retval = saa7164_api_i2c_read(bus, msgs[i].addr,
37 msgs[i].len, msgs[i].buf,
38 msgs[i+1].len, msgs[i+1].buf
39 );
40
41 i++;
42
43 if (retval < 0)
44 goto err;
45 } else {
46 /* write */
47 retval = saa7164_api_i2c_write(bus, msgs[i].addr,
48 msgs[i].len, msgs[i].buf);
49 }
50 if (retval < 0)
51 goto err;
52 }
53 return num;
54
55 err:
56 return retval;
57 }
58
saa7164_functionality(struct i2c_adapter * adap)59 static u32 saa7164_functionality(struct i2c_adapter *adap)
60 {
61 return I2C_FUNC_I2C;
62 }
63
64 static const struct i2c_algorithm saa7164_i2c_algo_template = {
65 .master_xfer = i2c_xfer,
66 .functionality = saa7164_functionality,
67 };
68
69 /* ----------------------------------------------------------------------- */
70
71 static const struct i2c_adapter saa7164_i2c_adap_template = {
72 .name = "saa7164",
73 .owner = THIS_MODULE,
74 .algo = &saa7164_i2c_algo_template,
75 };
76
77 static const struct i2c_client saa7164_i2c_client_template = {
78 .name = "saa7164 internal",
79 };
80
saa7164_i2c_register(struct saa7164_i2c * bus)81 int saa7164_i2c_register(struct saa7164_i2c *bus)
82 {
83 struct saa7164_dev *dev = bus->dev;
84
85 dprintk(DBGLVL_I2C, "%s(bus = %d)\n", __func__, bus->nr);
86
87 bus->i2c_adap = saa7164_i2c_adap_template;
88 bus->i2c_client = saa7164_i2c_client_template;
89
90 bus->i2c_adap.dev.parent = &dev->pci->dev;
91
92 strscpy(bus->i2c_adap.name, bus->dev->name,
93 sizeof(bus->i2c_adap.name));
94
95 bus->i2c_adap.algo_data = bus;
96 i2c_set_adapdata(&bus->i2c_adap, bus);
97 i2c_add_adapter(&bus->i2c_adap);
98
99 bus->i2c_client.adapter = &bus->i2c_adap;
100
101 if (0 != bus->i2c_rc)
102 printk(KERN_ERR "%s: i2c bus %d register FAILED\n",
103 dev->name, bus->nr);
104
105 return bus->i2c_rc;
106 }
107
saa7164_i2c_unregister(struct saa7164_i2c * bus)108 int saa7164_i2c_unregister(struct saa7164_i2c *bus)
109 {
110 i2c_del_adapter(&bus->i2c_adap);
111 return 0;
112 }
113