tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright 2009-2012 Freescale Semiconductor, Inc. All Rights Reserved.
4 *
5 * Author: Wu Guoxing <b39297@freescale.com>
6 */
7
8#include <linux/kernel.h>
9#include <linux/init.h>
10#include <linux/slab.h>
11#include <linux/i2c.h>
12#include <linux/gpio/driver.h>
13
14#define GPIO_GROUP_NUM 2
15#define GPIO_NUM_PER_GROUP 8
16#define GPIO_NUM (GPIO_GROUP_NUM*GPIO_NUM_PER_GROUP)
17
18struct mc9s08dz60 {
19 struct i2c_client *client;
20 struct gpio_chip chip;
21};
22
23static void mc9s_gpio_to_reg_and_bit(int offset, u8 *reg, u8 *bit)
24{
25 *reg = 0x20 + offset / GPIO_NUM_PER_GROUP;
26 *bit = offset % GPIO_NUM_PER_GROUP;
27}
28
29static int mc9s08dz60_get_value(struct gpio_chip *gc, unsigned offset)
30{
31 u8 reg, bit;
32 s32 value;
33 struct mc9s08dz60 *mc9s = gpiochip_get_data(gc);
34
35 mc9s_gpio_to_reg_and_bit(offset, ®, &bit);
36 value = i2c_smbus_read_byte_data(mc9s->client, reg);
37
38 return (value >= 0) ? (value >> bit) & 0x1 : 0;
39}
40
41static int mc9s08dz60_set(struct mc9s08dz60 *mc9s, unsigned offset, int val)
42{
43 u8 reg, bit;
44 s32 value;
45
46 mc9s_gpio_to_reg_and_bit(offset, ®, &bit);
47 value = i2c_smbus_read_byte_data(mc9s->client, reg);
48 if (value >= 0) {
49 if (val)
50 value |= 1 << bit;
51 else
52 value &= ~(1 << bit);
53
54 return i2c_smbus_write_byte_data(mc9s->client, reg, value);
55 } else
56 return value;
57
58}
59
60
61static void mc9s08dz60_set_value(struct gpio_chip *gc, unsigned offset, int val)
62{
63 struct mc9s08dz60 *mc9s = gpiochip_get_data(gc);
64
65 mc9s08dz60_set(mc9s, offset, val);
66}
67
68static int mc9s08dz60_direction_output(struct gpio_chip *gc,
69 unsigned offset, int val)
70{
71 struct mc9s08dz60 *mc9s = gpiochip_get_data(gc);
72
73 return mc9s08dz60_set(mc9s, offset, val);
74}
75
76static int mc9s08dz60_probe(struct i2c_client *client,
77 const struct i2c_device_id *id)
78{
79 struct mc9s08dz60 *mc9s;
80
81 mc9s = devm_kzalloc(&client->dev, sizeof(*mc9s), GFP_KERNEL);
82 if (!mc9s)
83 return -ENOMEM;
84
85 mc9s->chip.label = client->name;
86 mc9s->chip.base = -1;
87 mc9s->chip.parent = &client->dev;
88 mc9s->chip.owner = THIS_MODULE;
89 mc9s->chip.ngpio = GPIO_NUM;
90 mc9s->chip.can_sleep = true;
91 mc9s->chip.get = mc9s08dz60_get_value;
92 mc9s->chip.set = mc9s08dz60_set_value;
93 mc9s->chip.direction_output = mc9s08dz60_direction_output;
94 mc9s->client = client;
95 i2c_set_clientdata(client, mc9s);
96
97 return devm_gpiochip_add_data(&client->dev, &mc9s->chip, mc9s);
98}
99
100static const struct i2c_device_id mc9s08dz60_id[] = {
101 {"mc9s08dz60", 0},
102 {},
103};
104
105static struct i2c_driver mc9s08dz60_i2c_driver = {
106 .driver = {
107 .name = "mc9s08dz60",
108 },
109 .probe = mc9s08dz60_probe,
110 .id_table = mc9s08dz60_id,
111};
112builtin_i2c_driver(mc9s08dz60_i2c_driver);