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 | |
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 | addr: msgs[i].addr, |
30 | reglen: 0 /* reglen */, |
31 | NULL /* reg */, datalen: msgs[i].len, data: 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, addr: msgs[i].addr, |
37 | reglen: msgs[i].len, reg: msgs[i].buf, |
38 | datalen: msgs[i+1].len, data: 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, addr: msgs[i].addr, |
48 | datalen: msgs[i].len, data: msgs[i].buf); |
49 | } |
50 | if (retval < 0) |
51 | goto err; |
52 | } |
53 | return num; |
54 | |
55 | err: |
56 | return retval; |
57 | } |
58 | |
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 | |
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(adap: &bus->i2c_adap, data: bus); |
97 | i2c_add_adapter(adap: &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 | |
108 | int saa7164_i2c_unregister(struct saa7164_i2c *bus) |
109 | { |
110 | i2c_del_adapter(adap: &bus->i2c_adap); |
111 | return 0; |
112 | } |
113 | |