summaryrefslogtreecommitdiff
path: root/drivers/platform/x86/i2c-multi-instantiate.c
blob: ffb8d5d1eb5ffe3b661250b4edc6bb0c37a68119 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
// SPDX-License-Identifier: GPL-2.0+
/*
 * I2C multi-instantiate driver, pseudo driver to instantiate multiple
 * i2c-clients from a single fwnode.
 *
 * Copyright 2018 Hans de Goede <hdegoede@redhat.com>
 */

#include <linux/acpi.h>
#include <linux/bits.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/types.h>

#define IRQ_RESOURCE_TYPE	GENMASK(1, 0)
#define IRQ_RESOURCE_NONE	0
#define IRQ_RESOURCE_GPIO	1
#define IRQ_RESOURCE_APIC	2

struct i2c_inst_data {
	const char *type;
	unsigned int flags;
	int irq_idx;
};

struct i2c_multi_inst_data {
	int num_clients;
	struct i2c_client *clients[0];
};

static int i2c_multi_inst_count(struct acpi_resource *ares, void *data)
{
	struct acpi_resource_i2c_serialbus *sb;
	int *count = data;

	if (i2c_acpi_get_i2c_resource(ares, &sb))
		*count = *count + 1;

	return 1;
}

static int i2c_multi_inst_count_resources(struct acpi_device *adev)
{
	LIST_HEAD(r);
	int count = 0;
	int ret;

	ret = acpi_dev_get_resources(adev, &r, i2c_multi_inst_count, &count);
	if (ret < 0)
		return ret;

	acpi_dev_free_resource_list(&r);
	return count;
}

static int i2c_multi_inst_probe(struct platform_device *pdev)
{
	struct i2c_multi_inst_data *multi;
	const struct acpi_device_id *match;
	const struct i2c_inst_data *inst_data;
	struct i2c_board_info board_info = {};
	struct device *dev = &pdev->dev;
	struct acpi_device *adev;
	char name[32];
	int i, ret;

	match = acpi_match_device(dev->driver->acpi_match_table, dev);
	if (!match) {
		dev_err(dev, "Error ACPI match data is missing\n");
		return -ENODEV;
	}
	inst_data = (const struct i2c_inst_data *)match->driver_data;

	adev = ACPI_COMPANION(dev);

	/* Count number of clients to instantiate */
	ret = i2c_multi_inst_count_resources(adev);
	if (ret < 0)
		return ret;

	multi = devm_kmalloc(dev, struct_size(multi, clients, ret), GFP_KERNEL);
	if (!multi)
		return -ENOMEM;

	multi->num_clients = ret;

	for (i = 0; i < multi->num_clients && inst_data[i].type; i++) {
		memset(&board_info, 0, sizeof(board_info));
		strlcpy(board_info.type, inst_data[i].type, I2C_NAME_SIZE);
		snprintf(name, sizeof(name), "%s-%s.%d", dev_name(dev),
			 inst_data[i].type, i);
		board_info.dev_name = name;
		switch (inst_data[i].flags & IRQ_RESOURCE_TYPE) {
		case IRQ_RESOURCE_GPIO:
			ret = acpi_dev_gpio_irq_get(adev, inst_data[i].irq_idx);
			if (ret < 0) {
				dev_err(dev, "Error requesting irq at index %d: %d\n",
					inst_data[i].irq_idx, ret);
				goto error;
			}
			board_info.irq = ret;
			break;
		case IRQ_RESOURCE_APIC:
			ret = platform_get_irq(pdev, inst_data[i].irq_idx);
			if (ret < 0) {
				dev_dbg(dev, "Error requesting irq at index %d: %d\n",
					inst_data[i].irq_idx, ret);
				goto error;
			}
			board_info.irq = ret;
			break;
		default:
			board_info.irq = 0;
			break;
		}
		multi->clients[i] = i2c_acpi_new_device(dev, i, &board_info);
		if (IS_ERR(multi->clients[i])) {
			ret = PTR_ERR(multi->clients[i]);
			if (ret != -EPROBE_DEFER)
				dev_err(dev, "Error creating i2c-client, idx %d\n", i);
			goto error;
		}
	}
	if (i < multi->num_clients) {
		dev_err(dev, "Error finding driver, idx %d\n", i);
		ret = -ENODEV;
		goto error;
	}

	platform_set_drvdata(pdev, multi);
	return 0;

error:
	while (--i >= 0)
		i2c_unregister_device(multi->clients[i]);

	return ret;
}

static int i2c_multi_inst_remove(struct platform_device *pdev)
{
	struct i2c_multi_inst_data *multi = platform_get_drvdata(pdev);
	int i;

	for (i = 0; i < multi->num_clients; i++)
		i2c_unregister_device(multi->clients[i]);

	return 0;
}

static const struct i2c_inst_data bsg1160_data[]  = {
	{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
	{ "bmc150_magn" },
	{ "bmg160" },
	{}
};

static const struct i2c_inst_data bsg2150_data[]  = {
	{ "bmc150_accel", IRQ_RESOURCE_GPIO, 0 },
	{ "bmc150_magn" },
	/* The resources describe a 3th client, but it is not really there. */
	{ "bsg2150_dummy_dev" },
	{}
};

static const struct i2c_inst_data int3515_data[]  = {
	{ "tps6598x", IRQ_RESOURCE_APIC, 0 },
	{ "tps6598x", IRQ_RESOURCE_APIC, 1 },
	{ "tps6598x", IRQ_RESOURCE_APIC, 2 },
	{ "tps6598x", IRQ_RESOURCE_APIC, 3 },
	{}
};

/*
 * Note new device-ids must also be added to i2c_multi_instantiate_ids in
 * drivers/acpi/scan.c: acpi_device_enumeration_by_parent().
 */
static const struct acpi_device_id i2c_multi_inst_acpi_ids[] = {
	{ "BSG1160", (unsigned long)bsg1160_data },
	{ "BSG2150", (unsigned long)bsg2150_data },
	{ "INT3515", (unsigned long)int3515_data },
	{ }
};
MODULE_DEVICE_TABLE(acpi, i2c_multi_inst_acpi_ids);

static struct platform_driver i2c_multi_inst_driver = {
	.driver	= {
		.name = "I2C multi instantiate pseudo device driver",
		.acpi_match_table = ACPI_PTR(i2c_multi_inst_acpi_ids),
	},
	.probe = i2c_multi_inst_probe,
	.remove = i2c_multi_inst_remove,
};
module_platform_driver(i2c_multi_inst_driver);

MODULE_DESCRIPTION("I2C multi instantiate pseudo device driver");
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_LICENSE("GPL");