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 
18 struct mc9s08dz60 {
19 	struct i2c_client *client;
20 	struct gpio_chip chip;
21 };
22 
mc9s_gpio_to_reg_and_bit(int offset,u8 * reg,u8 * bit)23 static 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 
mc9s08dz60_get_value(struct gpio_chip * gc,unsigned offset)29 static 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, &reg, &bit);
36 	value = i2c_smbus_read_byte_data(mc9s->client, reg);
37 
38 	return (value >= 0) ? (value >> bit) & 0x1 : 0;
39 }
40 
mc9s08dz60_set(struct mc9s08dz60 * mc9s,unsigned offset,int val)41 static 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, &reg, &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 
mc9s08dz60_set_value(struct gpio_chip * gc,unsigned offset,int val)61 static 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 
mc9s08dz60_direction_output(struct gpio_chip * gc,unsigned offset,int val)68 static 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 
mc9s08dz60_probe(struct i2c_client * client,const struct i2c_device_id * id)76 static 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 
100 static const struct i2c_device_id mc9s08dz60_id[] = {
101 	{"mc9s08dz60", 0},
102 	{},
103 };
104 
105 static struct i2c_driver mc9s08dz60_i2c_driver = {
106 	.driver = {
107 		.name = "mc9s08dz60",
108 	},
109 	.probe = mc9s08dz60_probe,
110 	.id_table = mc9s08dz60_id,
111 };
112 builtin_i2c_driver(mc9s08dz60_i2c_driver);
113