summaryrefslogtreecommitdiff
path: root/drivers/platform/chrome/wilco_ec/core.c
blob: 3724bf4b77c61302556075542571ed9a5e67df70 (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
// SPDX-License-Identifier: GPL-2.0
/*
 * Core driver for Wilco Embedded Controller
 *
 * Copyright 2018 Google LLC
 *
 * This is the entry point for the drivers that control the Wilco EC.
 * This driver is responsible for several tasks:
 * - Initialize the register interface that is used by wilco_ec_mailbox()
 * - Create a platform device which is picked up by the debugfs driver
 * - Create a platform device which is picked up by the RTC driver
 */

#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/platform_data/wilco-ec.h>
#include <linux/platform_device.h>

#include "../cros_ec_lpc_mec.h"

#define DRV_NAME "wilco-ec"

static struct resource *wilco_get_resource(struct platform_device *pdev,
					   int index)
{
	struct device *dev = &pdev->dev;
	struct resource *res;

	res = platform_get_resource(pdev, IORESOURCE_IO, index);
	if (!res) {
		dev_dbg(dev, "Couldn't find IO resource %d\n", index);
		return res;
	}

	return devm_request_region(dev, res->start, resource_size(res),
				   dev_name(dev));
}

static int wilco_ec_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct wilco_ec_device *ec;
	int ret;

	ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL);
	if (!ec)
		return -ENOMEM;

	platform_set_drvdata(pdev, ec);
	ec->dev = dev;
	mutex_init(&ec->mailbox_lock);

	ec->data_size = sizeof(struct wilco_ec_response) + EC_MAILBOX_DATA_SIZE;
	ec->data_buffer = devm_kzalloc(dev, ec->data_size, GFP_KERNEL);
	if (!ec->data_buffer)
		return -ENOMEM;

	/* Prepare access to IO regions provided by ACPI */
	ec->io_data = wilco_get_resource(pdev, 0);	/* Host Data */
	ec->io_command = wilco_get_resource(pdev, 1);	/* Host Command */
	ec->io_packet = wilco_get_resource(pdev, 2);	/* MEC EMI */
	if (!ec->io_data || !ec->io_command || !ec->io_packet)
		return -ENODEV;

	/* Initialize cros_ec register interface for communication */
	cros_ec_lpc_mec_init(ec->io_packet->start,
			     ec->io_packet->start + EC_MAILBOX_DATA_SIZE);

	/*
	 * Register a child device that will be found by the debugfs driver.
	 * Ignore failure.
	 */
	ec->debugfs_pdev = platform_device_register_data(dev,
							 "wilco-ec-debugfs",
							 PLATFORM_DEVID_AUTO,
							 NULL, 0);

	/* Register a child device that will be found by the RTC driver. */
	ec->rtc_pdev = platform_device_register_data(dev, "rtc-wilco-ec",
						     PLATFORM_DEVID_AUTO,
						     NULL, 0);
	if (IS_ERR(ec->rtc_pdev)) {
		dev_err(dev, "Failed to create RTC platform device\n");
		ret = PTR_ERR(ec->rtc_pdev);
		goto unregister_debugfs;
	}

	ret = wilco_ec_add_sysfs(ec);
	if (ret < 0) {
		dev_err(dev, "Failed to create sysfs entries: %d", ret);
		goto unregister_rtc;
	}

	/* Register child device that will be found by the telemetry driver. */
	ec->telem_pdev = platform_device_register_data(dev, "wilco_telem",
						       PLATFORM_DEVID_AUTO,
						       ec, sizeof(*ec));
	if (IS_ERR(ec->telem_pdev)) {
		dev_err(dev, "Failed to create telemetry platform device\n");
		ret = PTR_ERR(ec->telem_pdev);
		goto remove_sysfs;
	}

	return 0;

remove_sysfs:
	wilco_ec_remove_sysfs(ec);
unregister_rtc:
	platform_device_unregister(ec->rtc_pdev);
unregister_debugfs:
	if (ec->debugfs_pdev)
		platform_device_unregister(ec->debugfs_pdev);
	cros_ec_lpc_mec_destroy();
	return ret;
}

static int wilco_ec_remove(struct platform_device *pdev)
{
	struct wilco_ec_device *ec = platform_get_drvdata(pdev);

	wilco_ec_remove_sysfs(ec);
	platform_device_unregister(ec->telem_pdev);
	platform_device_unregister(ec->rtc_pdev);
	if (ec->debugfs_pdev)
		platform_device_unregister(ec->debugfs_pdev);

	/* Teardown cros_ec interface */
	cros_ec_lpc_mec_destroy();

	return 0;
}

static const struct acpi_device_id wilco_ec_acpi_device_ids[] = {
	{ "GOOG000C", 0 },
	{ }
};
MODULE_DEVICE_TABLE(acpi, wilco_ec_acpi_device_ids);

static struct platform_driver wilco_ec_driver = {
	.driver = {
		.name = DRV_NAME,
		.acpi_match_table = wilco_ec_acpi_device_ids,
	},
	.probe = wilco_ec_probe,
	.remove = wilco_ec_remove,
};

module_platform_driver(wilco_ec_driver);

MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>");
MODULE_AUTHOR("Duncan Laurie <dlaurie@chromium.org>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("ChromeOS Wilco Embedded Controller driver");
MODULE_ALIAS("platform:" DRV_NAME);