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
 21static 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
 37static 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
123unregister_charge_config:
124	platform_device_unregister(ec->charger_pdev);
125remove_sysfs:
126	wilco_ec_remove_sysfs(ec);
127unregister_rtc:
128	platform_device_unregister(ec->rtc_pdev);
129unregister_debugfs:
130	if (ec->debugfs_pdev)
131		platform_device_unregister(ec->debugfs_pdev);
132	cros_ec_lpc_mec_destroy();
133	return ret;
134}
135
136static 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
153static const struct acpi_device_id wilco_ec_acpi_device_ids[] = {
154	{ "GOOG000C", 0 },
155	{ }
156};
157MODULE_DEVICE_TABLE(acpi, wilco_ec_acpi_device_ids);
158
159static 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
168module_platform_driver(wilco_ec_driver);
169
170MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>");
171MODULE_AUTHOR("Duncan Laurie <dlaurie@chromium.org>");
172MODULE_LICENSE("GPL v2");
173MODULE_DESCRIPTION("ChromeOS Wilco Embedded Controller driver");
174MODULE_ALIAS("platform:" DRV_NAME);