1/*
  2 * ChromeOS EC multi-function device
  3 *
  4 * Copyright (C) 2012 Google, Inc
  5 *
  6 * This software is licensed under the terms of the GNU General Public
  7 * License version 2, as published by the Free Software Foundation, and
  8 * may be copied, distributed, and modified under those terms.
  9 *
 10 * This program is distributed in the hope that it will be useful,
 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 13 * GNU General Public License for more details.
 14 *
 15 * The ChromeOS EC multi function device is used to mux all the requests
 16 * to the EC device for its multiple features: keyboard controller,
 17 * battery charging and regulator control, firmware update.
 18 */
 19
 20#include <linux/of_platform.h>
 21#include <linux/interrupt.h>
 22#include <linux/slab.h>
 23#include <linux/module.h>
 24#include <linux/mfd/core.h>
 25#include <linux/mfd/cros_ec.h>
 26
 27#define CROS_EC_DEV_EC_INDEX 0
 28#define CROS_EC_DEV_PD_INDEX 1
 29
 30static struct cros_ec_platform ec_p = {
 31	.ec_name = CROS_EC_DEV_NAME,
 32	.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_EC_INDEX),
 33};
 34
 35static struct cros_ec_platform pd_p = {
 36	.ec_name = CROS_EC_DEV_PD_NAME,
 37	.cmd_offset = EC_CMD_PASSTHRU_OFFSET(CROS_EC_DEV_PD_INDEX),
 38};
 39
 40static const struct mfd_cell ec_cell = {
 41	.name = "cros-ec-ctl",
 42	.platform_data = &ec_p,
 43	.pdata_size = sizeof(ec_p),
 44};
 45
 46static const struct mfd_cell ec_pd_cell = {
 47	.name = "cros-ec-ctl",
 48	.platform_data = &pd_p,
 49	.pdata_size = sizeof(pd_p),
 50};
 51
 52int cros_ec_register(struct cros_ec_device *ec_dev)
 53{
 54	struct device *dev = ec_dev->dev;
 55	int err = 0;
 56
 57	ec_dev->max_request = sizeof(struct ec_params_hello);
 58	ec_dev->max_response = sizeof(struct ec_response_get_protocol_info);
 59	ec_dev->max_passthru = 0;
 60
 61	ec_dev->din = devm_kzalloc(dev, ec_dev->din_size, GFP_KERNEL);
 62	if (!ec_dev->din)
 63		return -ENOMEM;
 64
 65	ec_dev->dout = devm_kzalloc(dev, ec_dev->dout_size, GFP_KERNEL);
 66	if (!ec_dev->dout)
 67		return -ENOMEM;
 68
 69	mutex_init(&ec_dev->lock);
 70
 71	cros_ec_query_all(ec_dev);
 72
 73	err = mfd_add_devices(ec_dev->dev, PLATFORM_DEVID_AUTO, &ec_cell, 1,
 74			      NULL, ec_dev->irq, NULL);
 75	if (err) {
 76		dev_err(dev,
 77			"Failed to register Embedded Controller subdevice %d\n",
 78			err);
 79		return err;
 80	}
 81
 82	if (ec_dev->max_passthru) {
 83		/*
 84		 * Register a PD device as well on top of this device.
 85		 * We make the following assumptions:
 86		 * - behind an EC, we have a pd
 87		 * - only one device added.
 88		 * - the EC is responsive at init time (it is not true for a
 89		 *   sensor hub.
 90		 */
 91		err = mfd_add_devices(ec_dev->dev, PLATFORM_DEVID_AUTO,
 92				      &ec_pd_cell, 1, NULL, ec_dev->irq, NULL);
 93		if (err) {
 94			dev_err(dev,
 95				"Failed to register Power Delivery subdevice %d\n",
 96				err);
 97			return err;
 98		}
 99	}
100
101	if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
102		err = of_platform_populate(dev->of_node, NULL, NULL, dev);
103		if (err) {
104			mfd_remove_devices(dev);
105			dev_err(dev, "Failed to register sub-devices\n");
106			return err;
107		}
108	}
109
110	dev_info(dev, "Chrome EC device registered\n");
111
112	return 0;
113}
114EXPORT_SYMBOL(cros_ec_register);
115
116int cros_ec_remove(struct cros_ec_device *ec_dev)
117{
118	mfd_remove_devices(ec_dev->dev);
119
120	return 0;
121}
122EXPORT_SYMBOL(cros_ec_remove);
123
124#ifdef CONFIG_PM_SLEEP
125int cros_ec_suspend(struct cros_ec_device *ec_dev)
126{
127	struct device *dev = ec_dev->dev;
128
129	if (device_may_wakeup(dev))
130		ec_dev->wake_enabled = !enable_irq_wake(ec_dev->irq);
131
132	disable_irq(ec_dev->irq);
133	ec_dev->was_wake_device = ec_dev->wake_enabled;
134
135	return 0;
136}
137EXPORT_SYMBOL(cros_ec_suspend);
138
139int cros_ec_resume(struct cros_ec_device *ec_dev)
140{
141	enable_irq(ec_dev->irq);
142
143	if (ec_dev->wake_enabled) {
144		disable_irq_wake(ec_dev->irq);
145		ec_dev->wake_enabled = 0;
146	}
147
148	return 0;
149}
150EXPORT_SYMBOL(cros_ec_resume);
151
152#endif
153
154MODULE_LICENSE("GPL");
155MODULE_DESCRIPTION("ChromeOS EC core driver");