[linux-block.git] / drivers / mfd / cros_ec_dev.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * cros_ec_dev - expose the Chrome OS Embedded Controller to user-space
 *
 * Copyright (C) 2014 Google, Inc.
 */

#include <linux/kconfig.h>
#include <linux/mfd/core.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/platform_data/cros_ec_chardev.h>
#include <linux/platform_data/cros_ec_commands.h>
#include <linux/platform_data/cros_ec_proto.h>
#include <linux/slab.h>

#define DRV_NAME "cros-ec-dev"

static struct class cros_class = {
	.owner          = THIS_MODULE,
	.name           = "chromeos",
};

/**
 * cros_feature_to_name - CrOS feature id to name/short description.
 * @id: The feature identifier.
 * @name: Device name associated with the feature id.
 * @desc: Short name that will be displayed.
 */
struct cros_feature_to_name {
	unsigned int id;
	const char *name;
	const char *desc;
};

/**
 * cros_feature_to_cells - CrOS feature id to mfd cells association.
 * @id: The feature identifier.
 * @mfd_cells: Pointer to the array of mfd cells that needs to be added.
 * @num_cells: Number of mfd cells into the array.
 */
struct cros_feature_to_cells {
	unsigned int id;
	const struct mfd_cell *mfd_cells;
	unsigned int num_cells;
};

static const struct cros_feature_to_name cros_mcu_devices[] = {
	{
		.id	= EC_FEATURE_FINGERPRINT,
		.name	= CROS_EC_DEV_FP_NAME,
		.desc	= "Fingerprint",
	},
	{
		.id	= EC_FEATURE_ISH,
		.name	= CROS_EC_DEV_ISH_NAME,
		.desc	= "Integrated Sensor Hub",
	},
	{
		.id	= EC_FEATURE_SCP,
		.name	= CROS_EC_DEV_SCP_NAME,
		.desc	= "System Control Processor",
	},
	{
		.id	= EC_FEATURE_TOUCHPAD,
		.name	= CROS_EC_DEV_TP_NAME,
		.desc	= "Touchpad",
	},
};

static const struct mfd_cell cros_ec_cec_cells[] = {
	{ .name = "cros-ec-cec", },
};

static const struct mfd_cell cros_ec_rtc_cells[] = {
	{ .name = "cros-ec-rtc", },
};

static const struct mfd_cell cros_ec_sensorhub_cells[] = {
	{ .name = "cros-ec-sensorhub", },
};

static const struct mfd_cell cros_usbpd_charger_cells[] = {
	{ .name = "cros-usbpd-charger", },
	{ .name = "cros-usbpd-logger", },
};

static const struct mfd_cell cros_usbpd_notify_cells[] = {
	{ .name = "cros-usbpd-notify", },
};

static const struct cros_feature_to_cells cros_subdevices[] = {
	{
		.id		= EC_FEATURE_CEC,
		.mfd_cells	= cros_ec_cec_cells,
		.num_cells	= ARRAY_SIZE(cros_ec_cec_cells),
	},
	{
		.id		= EC_FEATURE_RTC,
		.mfd_cells	= cros_ec_rtc_cells,
		.num_cells	= ARRAY_SIZE(cros_ec_rtc_cells),
	},
	{
		.id		= EC_FEATURE_USB_PD,
		.mfd_cells	= cros_usbpd_charger_cells,
		.num_cells	= ARRAY_SIZE(cros_usbpd_charger_cells),
	},
};

static const struct mfd_cell cros_ec_platform_cells[] = {
	{ .name = "cros-ec-chardev", },
	{ .name = "cros-ec-debugfs", },
	{ .name = "cros-ec-lightbar", },
	{ .name = "cros-ec-sysfs", },
};

static const struct mfd_cell cros_ec_vbc_cells[] = {
	{ .name = "cros-ec-vbc", }
};

static void cros_ec_class_release(struct device *dev)
{
	kfree(to_cros_ec_dev(dev));
}

static int ec_device_probe(struct platform_device *pdev)
{
	int retval = -ENOMEM;
	struct device_node *node;
	struct device *dev = &pdev->dev;
	struct cros_ec_platform *ec_platform = dev_get_platdata(dev);
	struct cros_ec_dev *ec = kzalloc(sizeof(*ec), GFP_KERNEL);
	int i;

	if (!ec)
		return retval;

	dev_set_drvdata(dev, ec);
	ec->ec_dev = dev_get_drvdata(dev->parent);
	ec->dev = dev;
	ec->cmd_offset = ec_platform->cmd_offset;
	ec->features[0] = -1U; /* Not cached yet */
	ec->features[1] = -1U; /* Not cached yet */
	device_initialize(&ec->class_dev);

	for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) {
		/*
		 * Check whether this is actually a dedicated MCU rather
		 * than an standard EC.
		 */
		if (cros_ec_check_features(ec, cros_mcu_devices[i].id)) {
			dev_info(dev, "CrOS %s MCU detected\n",
				 cros_mcu_devices[i].desc);
			/*
			 * Help userspace differentiating ECs from other MCU,
			 * regardless of the probing order.
			 */
			ec_platform->ec_name = cros_mcu_devices[i].name;
			break;
		}
	}

	/*
	 * Add the class device
	 */
	ec->class_dev.class = &cros_class;
	ec->class_dev.parent = dev;
	ec->class_dev.release = cros_ec_class_release;

	retval = dev_set_name(&ec->class_dev, "%s", ec_platform->ec_name);
	if (retval) {
		dev_err(dev, "dev_set_name failed => %d\n", retval);
		goto failed;
	}

	retval = device_add(&ec->class_dev);
	if (retval)
		goto failed;

	/* check whether this EC is a sensor hub. */
	if (cros_ec_get_sensor_count(ec) > 0) {
		retval = mfd_add_hotplug_devices(ec->dev,
				cros_ec_sensorhub_cells,
				ARRAY_SIZE(cros_ec_sensorhub_cells));
		if (retval)
			dev_err(ec->dev, "failed to add %s subdevice: %d\n",
				cros_ec_sensorhub_cells->name, retval);
	}

	/*
	 * The following subdevices can be detected by sending the
	 * EC_FEATURE_GET_CMD Embedded Controller device.
	 */
	for (i = 0; i < ARRAY_SIZE(cros_subdevices); i++) {
		if (cros_ec_check_features(ec, cros_subdevices[i].id)) {
			retval = mfd_add_hotplug_devices(ec->dev,
						cros_subdevices[i].mfd_cells,
						cros_subdevices[i].num_cells);
			if (retval)
				dev_err(ec->dev,
					"failed to add %s subdevice: %d\n",
					cros_subdevices[i].mfd_cells->name,
					retval);
		}
	}

	/*
	 * The PD notifier driver cell is separate since it only needs to be
	 * explicitly added on platforms that don't have the PD notifier ACPI
	 * device entry defined.
	 */
	if (IS_ENABLED(CONFIG_OF) && ec->ec_dev->dev->of_node) {
		if (cros_ec_check_features(ec, EC_FEATURE_USB_PD)) {
			retval = mfd_add_hotplug_devices(ec->dev,
					cros_usbpd_notify_cells,
					ARRAY_SIZE(cros_usbpd_notify_cells));
			if (retval)
				dev_err(ec->dev,
					"failed to add PD notify devices: %d\n",
					retval);
		}
	}

	/*
	 * The following subdevices cannot be detected by sending the
	 * EC_FEATURE_GET_CMD to the Embedded Controller device.
	 */
	retval = mfd_add_hotplug_devices(ec->dev, cros_ec_platform_cells,
					 ARRAY_SIZE(cros_ec_platform_cells));
	if (retval)
		dev_warn(ec->dev,
			 "failed to add cros-ec platform devices: %d\n",
			 retval);

	/* Check whether this EC instance has a VBC NVRAM */
	node = ec->ec_dev->dev->of_node;
	if (of_property_read_bool(node, "google,has-vbc-nvram")) {
		retval = mfd_add_hotplug_devices(ec->dev, cros_ec_vbc_cells,
						ARRAY_SIZE(cros_ec_vbc_cells));
		if (retval)
			dev_warn(ec->dev, "failed to add VBC devices: %d\n",
				 retval);
	}

	return 0;

failed:
	put_device(&ec->class_dev);
	return retval;
}

static int ec_device_remove(struct platform_device *pdev)
{
	struct cros_ec_dev *ec = dev_get_drvdata(&pdev->dev);

	mfd_remove_devices(ec->dev);
	device_unregister(&ec->class_dev);
	return 0;
}

static const struct platform_device_id cros_ec_id[] = {
	{ DRV_NAME, 0 },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(platform, cros_ec_id);

static struct platform_driver cros_ec_dev_driver = {
	.driver = {
		.name = DRV_NAME,
	},
	.id_table = cros_ec_id,
	.probe = ec_device_probe,
	.remove = ec_device_remove,
};

static int __init cros_ec_dev_init(void)
{
	int ret;

	ret  = class_register(&cros_class);
	if (ret) {
		pr_err(CROS_EC_DEV_NAME ": failed to register device class\n");
		return ret;
	}

	/* Register the driver */
	ret = platform_driver_register(&cros_ec_dev_driver);
	if (ret < 0) {
		pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret);
		goto failed_devreg;
	}
	return 0;

failed_devreg:
	class_unregister(&cros_class);
	return ret;
}

static void __exit cros_ec_dev_exit(void)
{
	platform_driver_unregister(&cros_ec_dev_driver);
	class_unregister(&cros_class);
}

module_init(cros_ec_dev_init);
module_exit(cros_ec_dev_exit);

MODULE_ALIAS("platform:" DRV_NAME);
MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>");
MODULE_DESCRIPTION("Userspace interface to the Chrome OS Embedded Controller");
MODULE_VERSION("1.0");
MODULE_LICENSE("GPL");
Commit	Line	Data
1ccea77e	1	// SPDX-License-Identifier: GPL-2.0-or-later
e7c256fb BR	2	/*
	3	* cros_ec_dev - expose the Chrome OS Embedded Controller to user-space
	4	*
	5	* Copyright (C) 2014 Google, Inc.
e7c256fb BR	6	*/
e7c256fb BR	7
4602dce0	8	#include <linux/kconfig.h>
5668bfdd	9	#include <linux/mfd/core.h>
e7c256fb	10	#include <linux/module.h>
ac316725	11	#include <linux/mod_devicetable.h>
0545625b	12	#include <linux/of_platform.h>
e7c256fb	13	#include <linux/platform_device.h>
459aedb9	14	#include <linux/platform_data/cros_ec_chardev.h>
840d9f13 EBS	15	#include <linux/platform_data/cros_ec_commands.h>
840d9f13 EBS	16	#include <linux/platform_data/cros_ec_proto.h>
a8411784	17	#include <linux/slab.h>
e7c256fb	18
ea01a31b TE	19	#define DRV_NAME "cros-ec-dev"
ea01a31b TE	20
57b33ff0 GG	21	static struct class cros_class = {
	22	.owner = THIS_MODULE,
	23	.name = "chromeos",
57b33ff0 GG	24	};
57b33ff0 GG	25
b027dcf7 EBS	26	/**
	27	* cros_feature_to_name - CrOS feature id to name/short description.
	28	* @id: The feature identifier.
	29	* @name: Device name associated with the feature id.
	30	* @desc: Short name that will be displayed.
	31	*/
	32	struct cros_feature_to_name {
	33	unsigned int id;
	34	const char *name;
	35	const char *desc;
	36	};
	37
832a636f EBS	38	/**
	39	* cros_feature_to_cells - CrOS feature id to mfd cells association.
	40	* @id: The feature identifier.
	41	* @mfd_cells: Pointer to the array of mfd cells that needs to be added.
	42	* @num_cells: Number of mfd cells into the array.
	43	*/
	44	struct cros_feature_to_cells {
	45	unsigned int id;
	46	const struct mfd_cell *mfd_cells;
	47	unsigned int num_cells;
	48	};
	49
b027dcf7 EBS	50	static const struct cros_feature_to_name cros_mcu_devices[] = {
	51	{
	52	.id = EC_FEATURE_FINGERPRINT,
	53	.name = CROS_EC_DEV_FP_NAME,
	54	.desc = "Fingerprint",
	55	},
	56	{
	57	.id = EC_FEATURE_ISH,
	58	.name = CROS_EC_DEV_ISH_NAME,
	59	.desc = "Integrated Sensor Hub",
	60	},
	61	{
	62	.id = EC_FEATURE_SCP,
	63	.name = CROS_EC_DEV_SCP_NAME,
	64	.desc = "System Control Processor",
	65	},
	66	{
	67	.id = EC_FEATURE_TOUCHPAD,
	68	.name = CROS_EC_DEV_TP_NAME,
	69	.desc = "Touchpad",
	70	},
	71	};
	72
832a636f EBS	73	static const struct mfd_cell cros_ec_cec_cells[] = {
	74	{ .name = "cros-ec-cec", },
	75	};
	76
	77	static const struct mfd_cell cros_ec_rtc_cells[] = {
	78	{ .name = "cros-ec-rtc", },
	79	};
	80
d60ac88a GG	81	static const struct mfd_cell cros_ec_sensorhub_cells[] = {
	82	{ .name = "cros-ec-sensorhub", },
	83	};
	84
832a636f EBS	85	static const struct mfd_cell cros_usbpd_charger_cells[] = {
	86	{ .name = "cros-usbpd-charger", },
	87	{ .name = "cros-usbpd-logger", },
	88	};
	89
4602dce0 PM	90	static const struct mfd_cell cros_usbpd_notify_cells[] = {
	91	{ .name = "cros-usbpd-notify", },
	92	};
	93
832a636f EBS	94	static const struct cros_feature_to_cells cros_subdevices[] = {
	95	{
	96	.id = EC_FEATURE_CEC,
	97	.mfd_cells = cros_ec_cec_cells,
	98	.num_cells = ARRAY_SIZE(cros_ec_cec_cells),
	99	},
	100	{
	101	.id = EC_FEATURE_RTC,
	102	.mfd_cells = cros_ec_rtc_cells,
	103	.num_cells = ARRAY_SIZE(cros_ec_rtc_cells),
	104	},
	105	{
	106	.id = EC_FEATURE_USB_PD,
	107	.mfd_cells = cros_usbpd_charger_cells,
	108	.num_cells = ARRAY_SIZE(cros_usbpd_charger_cells),
	109	},
	110	};
	111
	112	static const struct mfd_cell cros_ec_platform_cells[] = {
	113	{ .name = "cros-ec-chardev", },
	114	{ .name = "cros-ec-debugfs", },
	115	{ .name = "cros-ec-lightbar", },
	116	{ .name = "cros-ec-sysfs", },
	117	};
	118
	119	static const struct mfd_cell cros_ec_vbc_cells[] = {
	120	{ .name = "cros-ec-vbc", }
	121	};
	122
48a2ca0e EBS	123	static void cros_ec_class_release(struct device *dev)
	124	{
	125	kfree(to_cros_ec_dev(dev));
	126	}
	127
e7c256fb BR	128	static int ec_device_probe(struct platform_device *pdev)
e7c256fb BR	129	{
57b33ff0	130	int retval = -ENOMEM;
0545625b	131	struct device_node *node;
57b33ff0 GG	132	struct device *dev = &pdev->dev;
57b33ff0 GG	133	struct cros_ec_platform *ec_platform = dev_get_platdata(dev);
48a2ca0e	134	struct cros_ec_dev ec = kzalloc(sizeof(ec), GFP_KERNEL);
b027dcf7	135	int i;
57b33ff0 GG	136
	137	if (!ec)
	138	return retval;
e7c256fb	139
57b33ff0 GG	140	dev_set_drvdata(dev, ec);
	141	ec->ec_dev = dev_get_drvdata(dev->parent);
	142	ec->dev = dev;
	143	ec->cmd_offset = ec_platform->cmd_offset;
e4244ebd VP	144	ec->features[0] = -1U; /* Not cached yet */
e4244ebd VP	145	ec->features[1] = -1U; /* Not cached yet */
57b33ff0	146	device_initialize(&ec->class_dev);
e7c256fb	147
b027dcf7	148	for (i = 0; i < ARRAY_SIZE(cros_mcu_devices); i++) {
90486af5	149	/*
b027dcf7 EBS	150	* Check whether this is actually a dedicated MCU rather
b027dcf7 EBS	151	* than an standard EC.
90486af5	152	*/
b027dcf7 EBS	153	if (cros_ec_check_features(ec, cros_mcu_devices[i].id)) {
	154	dev_info(dev, "CrOS %s MCU detected\n",
	155	cros_mcu_devices[i].desc);
	156	/*
	157	* Help userspace differentiating ECs from other MCU,
	158	* regardless of the probing order.
	159	*/
	160	ec_platform->ec_name = cros_mcu_devices[i].name;
	161	break;
	162	}
554e937e PHS	163	}
554e937e PHS	164
57b33ff0 GG	165	/*
57b33ff0 GG	166	* Add the class device
57b33ff0	167	*/
57b33ff0 GG	168	ec->class_dev.class = &cros_class;
57b33ff0 GG	169	ec->class_dev.parent = dev;
48a2ca0e	170	ec->class_dev.release = cros_ec_class_release;
57b33ff0 GG	171
	172	retval = dev_set_name(&ec->class_dev, "%s", ec_platform->ec_name);
	173	if (retval) {
	174	dev_err(dev, "dev_set_name failed => %d\n", retval);
1c1d152c	175	goto failed;
e7c256fb BR	176	}
e7c256fb BR	177
459aedb9 EBS	178	retval = device_add(&ec->class_dev);
	179	if (retval)
	180	goto failed;
	181
c1d1e91a	182	/* check whether this EC is a sensor hub. */
d60ac88a GG	183	if (cros_ec_get_sensor_count(ec) > 0) {
	184	retval = mfd_add_hotplug_devices(ec->dev,
	185	cros_ec_sensorhub_cells,
	186	ARRAY_SIZE(cros_ec_sensorhub_cells));
	187	if (retval)
	188	dev_err(ec->dev, "failed to add %s subdevice: %d\n",
	189	cros_ec_sensorhub_cells->name, retval);
	190	}
c1d1e91a	191
832a636f EBS	192	/*
	193	* The following subdevices can be detected by sending the
	194	* EC_FEATURE_GET_CMD Embedded Controller device.
	195	*/
	196	for (i = 0; i < ARRAY_SIZE(cros_subdevices); i++) {
	197	if (cros_ec_check_features(ec, cros_subdevices[i].id)) {
	198	retval = mfd_add_hotplug_devices(ec->dev,
	199	cros_subdevices[i].mfd_cells,
	200	cros_subdevices[i].num_cells);
	201	if (retval)
	202	dev_err(ec->dev,
	203	"failed to add %s subdevice: %d\n",
	204	cros_subdevices[i].mfd_cells->name,
	205	retval);
	206	}
3144dce7 EBS	207	}
3144dce7 EBS	208
4602dce0 PM	209	/*
	210	* The PD notifier driver cell is separate since it only needs to be
	211	* explicitly added on platforms that don't have the PD notifier ACPI
	212	* device entry defined.
	213	*/
f8db89d1	214	if (IS_ENABLED(CONFIG_OF) && ec->ec_dev->dev->of_node) {
4602dce0 PM	215	if (cros_ec_check_features(ec, EC_FEATURE_USB_PD)) {
	216	retval = mfd_add_hotplug_devices(ec->dev,
	217	cros_usbpd_notify_cells,
	218	ARRAY_SIZE(cros_usbpd_notify_cells));
	219	if (retval)
	220	dev_err(ec->dev,
	221	"failed to add PD notify devices: %d\n",
	222	retval);
	223	}
	224	}
	225
832a636f EBS	226	/*
	227	* The following subdevices cannot be detected by sending the
	228	* EC_FEATURE_GET_CMD to the Embedded Controller device.
	229	*/
28e6fcc8 EBS	230	retval = mfd_add_hotplug_devices(ec->dev, cros_ec_platform_cells,
28e6fcc8 EBS	231	ARRAY_SIZE(cros_ec_platform_cells));
ecf8a6cd EBS	232	if (retval)
	233	dev_warn(ec->dev,
	234	"failed to add cros-ec platform devices: %d\n",
	235	retval);
	236
0545625b EBS	237	/* Check whether this EC instance has a VBC NVRAM */
	238	node = ec->ec_dev->dev->of_node;
	239	if (of_property_read_bool(node, "google,has-vbc-nvram")) {
28e6fcc8 EBS	240	retval = mfd_add_hotplug_devices(ec->dev, cros_ec_vbc_cells,
28e6fcc8 EBS	241	ARRAY_SIZE(cros_ec_vbc_cells));
0545625b EBS	242	if (retval)
	243	dev_warn(ec->dev, "failed to add VBC devices: %d\n",
	244	retval);
	245	}
	246
e7c256fb	247	return 0;
57b33ff0	248
1c1d152c LG	249	failed:
1c1d152c LG	250	put_device(&ec->class_dev);
57b33ff0	251	return retval;
e7c256fb BR	252	}
	253
	254	static int ec_device_remove(struct platform_device *pdev)
	255	{
57b33ff0	256	struct cros_ec_dev *ec = dev_get_drvdata(&pdev->dev);
e8626459	257
18e294dd	258	mfd_remove_devices(ec->dev);
57b33ff0	259	device_unregister(&ec->class_dev);
e7c256fb BR	260	return 0;
	261	}
	262
afbf8ec7	263	static const struct platform_device_id cros_ec_id[] = {
ea01a31b	264	{ DRV_NAME, 0 },
abeed71b	265	{ /* sentinel */ }
afbf8ec7 JMC	266	};
	267	MODULE_DEVICE_TABLE(platform, cros_ec_id);
	268
e7c256fb BR	269	static struct platform_driver cros_ec_dev_driver = {
e7c256fb BR	270	.driver = {
ea01a31b	271	.name = DRV_NAME,
e7c256fb	272	},
6eb35784	273	.id_table = cros_ec_id,
e7c256fb BR	274	.probe = ec_device_probe,
	275	.remove = ec_device_remove,
	276	};
	277
	278	static int __init cros_ec_dev_init(void)
	279	{
	280	int ret;
e7c256fb	281
57b33ff0 GG	282	ret = class_register(&cros_class);
57b33ff0 GG	283	if (ret) {
e7c256fb	284	pr_err(CROS_EC_DEV_NAME ": failed to register device class\n");
57b33ff0	285	return ret;
e7c256fb BR	286	}
e7c256fb BR	287
e7c256fb BR	288	/* Register the driver */
	289	ret = platform_driver_register(&cros_ec_dev_driver);
	290	if (ret < 0) {
	291	pr_warn(CROS_EC_DEV_NAME ": can't register driver: %d\n", ret);
	292	goto failed_devreg;
	293	}
	294	return 0;
	295
	296	failed_devreg:
57b33ff0	297	class_unregister(&cros_class);
e7c256fb BR	298	return ret;
	299	}
	300
	301	static void __exit cros_ec_dev_exit(void)
	302	{
	303	platform_driver_unregister(&cros_ec_dev_driver);
57b33ff0	304	class_unregister(&cros_class);
e7c256fb BR	305	}
	306
	307	module_init(cros_ec_dev_init);
	308	module_exit(cros_ec_dev_exit);
	309
ea01a31b	310	MODULE_ALIAS("platform:" DRV_NAME);
e7c256fb BR	311	MODULE_AUTHOR("Bill Richardson <wfrichar@chromium.org>");
	312	MODULE_DESCRIPTION("Userspace interface to the Chrome OS Embedded Controller");
	313	MODULE_VERSION("1.0");
	314	MODULE_LICENSE("GPL");