1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Core driver for Wilco Embedded Controller
4 *
5 * Copyright 2018 Google LLC
6 *
7 * This is the entry point for the drivers that control the Wilco EC.
8 */
9
10 #include <linux/acpi.h>
11 #include <linux/device.h>
12 #include <linux/ioport.h>
13 #include <linux/module.h>
14 #include <linux/platform_data/wilco-ec.h>
15 #include <linux/platform_device.h>
16
17 #include "../cros_ec_lpc_mec.h"
18
19 #define DRV_NAME "wilco-ec"
20
wilco_get_resource(struct platform_device * pdev,int index)21 static struct resource *wilco_get_resource(struct platform_device *pdev,
22 int index)
23 {
24 struct device *dev = &pdev->dev;
25 struct resource *res;
26
27 res = platform_get_resource(pdev, IORESOURCE_IO, index);
28 if (!res) {
29 dev_dbg(dev, "Couldn't find IO resource %d\n", index);
30 return res;
31 }
32
33 return devm_request_region(dev, res->start, resource_size(res),
34 dev_name(dev));
35 }
36
wilco_ec_probe(struct platform_device * pdev)37 static int wilco_ec_probe(struct platform_device *pdev)
38 {
39 struct device *dev = &pdev->dev;
40 struct wilco_ec_device *ec;
41 int ret;
42
43 ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL);
44 if (!ec)
45 return -ENOMEM;
46
47 platform_set_drvdata(pdev, ec);
48 ec->dev = dev;
49 mutex_init(&ec->mailbox_lock);
50
51 ec->data_size = sizeof(struct wilco_ec_response) + EC_MAILBOX_DATA_SIZE;
52 ec->data_buffer = devm_kzalloc(dev, ec->data_size, GFP_KERNEL);
53 if (!ec->data_buffer)
54 return -ENOMEM;
55
56 /* Prepare access to IO regions provided by ACPI */
57 ec->io_data = wilco_get_resource(pdev, 0); /* Host Data */
58 ec->io_command = wilco_get_resource(pdev, 1); /* Host Command */
59 ec->io_packet = wilco_get_resource(pdev, 2); /* MEC EMI */
60 if (!ec->io_data || !ec->io_command || !ec->io_packet)
61 return -ENODEV;
62
63 /* Initialize cros_ec register interface for communication */
64 cros_ec_lpc_mec_init(ec->io_packet->start,
65 ec->io_packet->start + EC_MAILBOX_DATA_SIZE);
66
67 /*
68 * Register a child device that will be found by the debugfs driver.
69 * Ignore failure.
70 */
71 ec->debugfs_pdev = platform_device_register_data(dev,
72 "wilco-ec-debugfs",
73 PLATFORM_DEVID_AUTO,
74 NULL, 0);
75
76 /* Register a child device that will be found by the RTC driver. */
77 ec->rtc_pdev = platform_device_register_data(dev, "rtc-wilco-ec",
78 PLATFORM_DEVID_AUTO,
79 NULL, 0);
80 if (IS_ERR(ec->rtc_pdev)) {
81 dev_err(dev, "Failed to create RTC platform device\n");
82 ret = PTR_ERR(ec->rtc_pdev);
83 goto unregister_debugfs;
84 }
85
86 /* Set up the keyboard backlight LEDs. */
87 ret = wilco_keyboard_leds_init(ec);
88 if (ret < 0) {
89 dev_err(dev,
90 "Failed to initialize keyboard LEDs: %d\n",
91 ret);
92 goto unregister_rtc;
93 }
94
95 ret = wilco_ec_add_sysfs(ec);
96 if (ret < 0) {
97 dev_err(dev, "Failed to create sysfs entries: %d\n", ret);
98 goto unregister_rtc;
99 }
100
101 /* Register child device to be found by charger config driver. */
102 ec->charger_pdev = platform_device_register_data(dev, "wilco-charger",
103 PLATFORM_DEVID_AUTO,
104 NULL, 0);
105 if (IS_ERR(ec->charger_pdev)) {
106 dev_err(dev, "Failed to create charger platform device\n");
107 ret = PTR_ERR(ec->charger_pdev);
108 goto remove_sysfs;
109 }
110
111 /* Register child device that will be found by the telemetry driver. */
112 ec->telem_pdev = platform_device_register_data(dev, "wilco_telem",
113 PLATFORM_DEVID_AUTO,
114 ec, sizeof(*ec));
115 if (IS_ERR(ec->telem_pdev)) {
116 dev_err(dev, "Failed to create telemetry platform device\n");
117 ret = PTR_ERR(ec->telem_pdev);
118 goto unregister_charge_config;
119 }
120
121 return 0;
122
123 unregister_charge_config:
124 platform_device_unregister(ec->charger_pdev);
125 remove_sysfs:
126 wilco_ec_remove_sysfs(ec);
127 unregister_rtc:
128 platform_device_unregister(ec->rtc_pdev);
129 unregister_debugfs:
130 if (ec->debugfs_pdev)
131 platform_device_unregister(ec->debugfs_pdev);
132 cros_ec_lpc_mec_destroy();
133 return ret;
134 }
135
wilco_ec_remove(struct platform_device * pdev)136 static int wilco_ec_remove(struct platform_device *pdev)
137 {
138 struct wilco_ec_device *ec = platform_get_drvdata(pdev);
139
140 platform_device_unregister(ec->telem_pdev);
141 platform_device_unregister(ec->charger_pdev);
142 wilco_ec_remove_sysfs(ec);
143 platform_device_unregister(ec->rtc_pdev);
144 if (ec->debugfs_pdev)
145 platform_device_unregister(ec->debugfs_pdev);
146
147 /* Teardown cros_ec interface */
148 cros_ec_lpc_mec_destroy();
149
150 return 0;
151 }
152
153 static const struct acpi_device_id wilco_ec_acpi_device_ids[] = {
154 { "GOOG000C", 0 },
155 { }
156 };
157 MODULE_DEVICE_TABLE(acpi, wilco_ec_acpi_device_ids);
158
159 static struct platform_driver wilco_ec_driver = {
160 .driver = {
161 .name = DRV_NAME,
162 .acpi_match_table = wilco_ec_acpi_device_ids,
163 },
164 .probe = wilco_ec_probe,
165 .remove = wilco_ec_remove,
166 };
167
168 module_platform_driver(wilco_ec_driver);
169
170 MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>");
171 MODULE_AUTHOR("Duncan Laurie <dlaurie@chromium.org>");
172 MODULE_LICENSE("GPL v2");
173 MODULE_DESCRIPTION("ChromeOS Wilco Embedded Controller driver");
174 MODULE_ALIAS("platform:" DRV_NAME);
175
