[linux-block.git] / drivers / char / tpm / tpm-chip.c

/*
 * Copyright (C) 2004 IBM Corporation
 * Copyright (C) 2014 Intel Corporation
 *
 * Authors:
 * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
 * Leendert van Doorn <leendert@watson.ibm.com>
 * Dave Safford <safford@watson.ibm.com>
 * Reiner Sailer <sailer@watson.ibm.com>
 * Kylene Hall <kjhall@us.ibm.com>
 *
 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
 *
 * TPM chip management routines.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, version 2 of the
 * License.
 *
 */

#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/freezer.h>
#include <linux/major.h>
#include "tpm.h"
#include "tpm_eventlog.h"

DEFINE_IDR(dev_nums_idr);
static DEFINE_MUTEX(idr_lock);

struct class *tpm_class;
struct class *tpmrm_class;
dev_t tpm_devt;

/**
 * tpm_try_get_ops() - Get a ref to the tpm_chip
 * @chip: Chip to ref
 *
 * The caller must already have some kind of locking to ensure that chip is
 * valid. This function will lock the chip so that the ops member can be
 * accessed safely. The locking prevents tpm_chip_unregister from
 * completing, so it should not be held for long periods.
 *
 * Returns -ERRNO if the chip could not be got.
 */
int tpm_try_get_ops(struct tpm_chip *chip)
{
	int rc = -EIO;

	get_device(&chip->dev);

	down_read(&chip->ops_sem);
	if (!chip->ops)
		goto out_lock;

	return 0;
out_lock:
	up_read(&chip->ops_sem);
	put_device(&chip->dev);
	return rc;
}
EXPORT_SYMBOL_GPL(tpm_try_get_ops);

/**
 * tpm_put_ops() - Release a ref to the tpm_chip
 * @chip: Chip to put
 *
 * This is the opposite pair to tpm_try_get_ops(). After this returns chip may
 * be kfree'd.
 */
void tpm_put_ops(struct tpm_chip *chip)
{
	up_read(&chip->ops_sem);
	put_device(&chip->dev);
}
EXPORT_SYMBOL_GPL(tpm_put_ops);

/**
 * tpm_chip_find_get() - return tpm_chip for a given chip number
 * @chip_num: id to find
 *
 * The return'd chip has been tpm_try_get_ops'd and must be released via
 * tpm_put_ops
 */
struct tpm_chip *tpm_chip_find_get(int chip_num)
{
	struct tpm_chip *chip, *res = NULL;
	int chip_prev;

	mutex_lock(&idr_lock);

	if (chip_num == TPM_ANY_NUM) {
		chip_num = 0;
		do {
			chip_prev = chip_num;
			chip = idr_get_next(&dev_nums_idr, &chip_num);
			if (chip && !tpm_try_get_ops(chip)) {
				res = chip;
				break;
			}
		} while (chip_prev != chip_num);
	} else {
		chip = idr_find(&dev_nums_idr, chip_num);
		if (chip && !tpm_try_get_ops(chip))
			res = chip;
	}

	mutex_unlock(&idr_lock);

	return res;
}

/**
 * tpm_dev_release() - free chip memory and the device number
 * @dev: the character device for the TPM chip
 *
 * This is used as the release function for the character device.
 */
static void tpm_dev_release(struct device *dev)
{
	struct tpm_chip *chip = container_of(dev, struct tpm_chip, dev);

	mutex_lock(&idr_lock);
	idr_remove(&dev_nums_idr, chip->dev_num);
	mutex_unlock(&idr_lock);

	kfree(chip->log.bios_event_log);
	kfree(chip->work_space.context_buf);
	kfree(chip->work_space.session_buf);
	kfree(chip);
}

static void tpm_devs_release(struct device *dev)
{
	struct tpm_chip *chip = container_of(dev, struct tpm_chip, devs);

	/* release the master device reference */
	put_device(&chip->dev);
}

/**
 * tpm_chip_alloc() - allocate a new struct tpm_chip instance
 * @pdev: device to which the chip is associated
 *        At this point pdev mst be initialized, but does not have to
 *        be registered
 * @ops: struct tpm_class_ops instance
 *
 * Allocates a new struct tpm_chip instance and assigns a free
 * device number for it. Must be paired with put_device(&chip->dev).
 */
struct tpm_chip *tpm_chip_alloc(struct device *pdev,
				const struct tpm_class_ops *ops)
{
	struct tpm_chip *chip;
	int rc;

	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
	if (chip == NULL)
		return ERR_PTR(-ENOMEM);

	mutex_init(&chip->tpm_mutex);
	init_rwsem(&chip->ops_sem);

	chip->ops = ops;

	mutex_lock(&idr_lock);
	rc = idr_alloc(&dev_nums_idr, NULL, 0, TPM_NUM_DEVICES, GFP_KERNEL);
	mutex_unlock(&idr_lock);
	if (rc < 0) {
		dev_err(pdev, "No available tpm device numbers\n");
		kfree(chip);
		return ERR_PTR(rc);
	}
	chip->dev_num = rc;

	device_initialize(&chip->dev);
	device_initialize(&chip->devs);

	chip->dev.class = tpm_class;
	chip->dev.release = tpm_dev_release;
	chip->dev.parent = pdev;
	chip->dev.groups = chip->groups;

	chip->devs.parent = pdev;
	chip->devs.class = tpmrm_class;
	chip->devs.release = tpm_devs_release;
	/* get extra reference on main device to hold on
	 * behalf of devs.  This holds the chip structure
	 * while cdevs is in use.  The corresponding put
	 * is in the tpm_devs_release
	 */
	get_device(&chip->dev);

	if (chip->dev_num == 0)
		chip->dev.devt = MKDEV(MISC_MAJOR, TPM_MINOR);
	else
		chip->dev.devt = MKDEV(MAJOR(tpm_devt), chip->dev_num);

	chip->devs.devt =
		MKDEV(MAJOR(tpm_devt), chip->dev_num + TPM_NUM_DEVICES);

	rc = dev_set_name(&chip->dev, "tpm%d", chip->dev_num);
	if (rc)
		goto out;
	rc = dev_set_name(&chip->devs, "tpmrm%d", chip->dev_num);
	if (rc)
		goto out;

	if (!pdev)
		chip->flags |= TPM_CHIP_FLAG_VIRTUAL;

	cdev_init(&chip->cdev, &tpm_fops);
	cdev_init(&chip->cdevs, &tpmrm_fops);
	chip->cdev.owner = THIS_MODULE;
	chip->cdevs.owner = THIS_MODULE;
	chip->cdev.kobj.parent = &chip->dev.kobj;
	chip->cdevs.kobj.parent = &chip->devs.kobj;

	chip->work_space.context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
	if (!chip->work_space.context_buf) {
		rc = -ENOMEM;
		goto out;
	}
	chip->work_space.session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
	if (!chip->work_space.session_buf) {
		rc = -ENOMEM;
		goto out;
	}

	return chip;

out:
	put_device(&chip->devs);
	put_device(&chip->dev);
	return ERR_PTR(rc);
}
EXPORT_SYMBOL_GPL(tpm_chip_alloc);

/**
 * tpmm_chip_alloc() - allocate a new struct tpm_chip instance
 * @pdev: parent device to which the chip is associated
 * @ops: struct tpm_class_ops instance
 *
 * Same as tpm_chip_alloc except devm is used to do the put_device
 */
struct tpm_chip *tpmm_chip_alloc(struct device *pdev,
				 const struct tpm_class_ops *ops)
{
	struct tpm_chip *chip;
	int rc;

	chip = tpm_chip_alloc(pdev, ops);
	if (IS_ERR(chip))
		return chip;

	rc = devm_add_action_or_reset(pdev,
				      (void (*)(void *)) put_device,
				      &chip->dev);
	if (rc)
		return ERR_PTR(rc);

	dev_set_drvdata(pdev, chip);

	return chip;
}
EXPORT_SYMBOL_GPL(tpmm_chip_alloc);

static int tpm_add_char_device(struct tpm_chip *chip)
{
	int rc;

	rc = cdev_add(&chip->cdev, chip->dev.devt, 1);
	if (rc) {
		dev_err(&chip->dev,
			"unable to cdev_add() %s, major %d, minor %d, err=%d\n",
			dev_name(&chip->dev), MAJOR(chip->dev.devt),
			MINOR(chip->dev.devt), rc);
		return rc;
	}

	rc = device_add(&chip->dev);
	if (rc) {
		dev_err(&chip->dev,
			"unable to device_register() %s, major %d, minor %d, err=%d\n",
			dev_name(&chip->dev), MAJOR(chip->dev.devt),
			MINOR(chip->dev.devt), rc);

		cdev_del(&chip->cdev);
		return rc;
	}

	if (chip->flags & TPM_CHIP_FLAG_TPM2)
		rc = cdev_add(&chip->cdevs, chip->devs.devt, 1);
	if (rc) {
		dev_err(&chip->dev,
			"unable to cdev_add() %s, major %d, minor %d, err=%d\n",
			dev_name(&chip->devs), MAJOR(chip->devs.devt),
			MINOR(chip->devs.devt), rc);
		return rc;
	}

	if (chip->flags & TPM_CHIP_FLAG_TPM2)
		rc = device_add(&chip->devs);
	if (rc) {
		dev_err(&chip->dev,
			"unable to device_register() %s, major %d, minor %d, err=%d\n",
			dev_name(&chip->devs), MAJOR(chip->devs.devt),
			MINOR(chip->devs.devt), rc);
		cdev_del(&chip->cdevs);
		return rc;
	}

	/* Make the chip available. */
	mutex_lock(&idr_lock);
	idr_replace(&dev_nums_idr, chip, chip->dev_num);
	mutex_unlock(&idr_lock);

	return rc;
}

static void tpm_del_char_device(struct tpm_chip *chip)
{
	cdev_del(&chip->cdev);
	device_del(&chip->dev);

	/* Make the chip unavailable. */
	mutex_lock(&idr_lock);
	idr_replace(&dev_nums_idr, NULL, chip->dev_num);
	mutex_unlock(&idr_lock);

	/* Make the driver uncallable. */
	down_write(&chip->ops_sem);
	if (chip->flags & TPM_CHIP_FLAG_TPM2)
		tpm2_shutdown(chip, TPM2_SU_CLEAR);
	chip->ops = NULL;
	up_write(&chip->ops_sem);
}

static void tpm_del_legacy_sysfs(struct tpm_chip *chip)
{
	struct attribute **i;

	if (chip->flags & (TPM_CHIP_FLAG_TPM2 | TPM_CHIP_FLAG_VIRTUAL))
		return;

	sysfs_remove_link(&chip->dev.parent->kobj, "ppi");

	for (i = chip->groups[0]->attrs; *i != NULL; ++i)
		sysfs_remove_link(&chip->dev.parent->kobj, (*i)->name);
}

/* For compatibility with legacy sysfs paths we provide symlinks from the
 * parent dev directory to selected names within the tpm chip directory. Old
 * kernel versions created these files directly under the parent.
 */
static int tpm_add_legacy_sysfs(struct tpm_chip *chip)
{
	struct attribute **i;
	int rc;

	if (chip->flags & (TPM_CHIP_FLAG_TPM2 | TPM_CHIP_FLAG_VIRTUAL))
		return 0;

	rc = __compat_only_sysfs_link_entry_to_kobj(
		    &chip->dev.parent->kobj, &chip->dev.kobj, "ppi");
	if (rc && rc != -ENOENT)
		return rc;

	/* All the names from tpm-sysfs */
	for (i = chip->groups[0]->attrs; *i != NULL; ++i) {
		rc = __compat_only_sysfs_link_entry_to_kobj(
		    &chip->dev.parent->kobj, &chip->dev.kobj, (*i)->name);
		if (rc) {
			tpm_del_legacy_sysfs(chip);
			return rc;
		}
	}

	return 0;
}
/*
 * tpm_chip_register() - create a character device for the TPM chip
 * @chip: TPM chip to use.
 *
 * Creates a character device for the TPM chip and adds sysfs attributes for
 * the device. As the last step this function adds the chip to the list of TPM
 * chips available for in-kernel use.
 *
 * This function should be only called after the chip initialization is
 * complete.
 */
int tpm_chip_register(struct tpm_chip *chip)
{
	int rc;

	if (chip->ops->flags & TPM_OPS_AUTO_STARTUP) {
		if (chip->flags & TPM_CHIP_FLAG_TPM2)
			rc = tpm2_auto_startup(chip);
		else
			rc = tpm1_auto_startup(chip);
		if (rc)
			return rc;
	}

	tpm_sysfs_add_device(chip);

	rc = tpm_bios_log_setup(chip);
	if (rc != 0 && rc != -ENODEV)
		return rc;

	tpm_add_ppi(chip);

	rc = tpm_add_char_device(chip);
	if (rc) {
		tpm_bios_log_teardown(chip);
		return rc;
	}

	rc = tpm_add_legacy_sysfs(chip);
	if (rc) {
		tpm_chip_unregister(chip);
		return rc;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(tpm_chip_register);

/*
 * tpm_chip_unregister() - release the TPM driver
 * @chip: TPM chip to use.
 *
 * Takes the chip first away from the list of available TPM chips and then
 * cleans up all the resources reserved by tpm_chip_register().
 *
 * Once this function returns the driver call backs in 'op's will not be
 * running and will no longer start.
 *
 * NOTE: This function should be only called before deinitializing chip
 * resources.
 */
void tpm_chip_unregister(struct tpm_chip *chip)
{
	tpm_del_legacy_sysfs(chip);
	tpm_bios_log_teardown(chip);
	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
		cdev_del(&chip->cdevs);
		device_del(&chip->devs);
	}
	tpm_del_char_device(chip);
}
EXPORT_SYMBOL_GPL(tpm_chip_unregister);
Commit	Line	Data
afb5abc2 JS	1	/*
	2	* Copyright (C) 2004 IBM Corporation
	3	* Copyright (C) 2014 Intel Corporation
	4	*
	5	* Authors:
	6	* Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
	7	* Leendert van Doorn <leendert@watson.ibm.com>
	8	* Dave Safford <safford@watson.ibm.com>
	9	* Reiner Sailer <sailer@watson.ibm.com>
	10	* Kylene Hall <kjhall@us.ibm.com>
	11	*
	12	* Maintained by: <tpmdd-devel@lists.sourceforge.net>
	13	*
	14	* TPM chip management routines.
	15	*
	16	* This program is free software; you can redistribute it and/or
	17	* modify it under the terms of the GNU General Public License as
	18	* published by the Free Software Foundation, version 2 of the
	19	* License.
	20	*
	21	*/
	22
	23	#include <linux/poll.h>
	24	#include <linux/slab.h>
	25	#include <linux/mutex.h>
	26	#include <linux/spinlock.h>
	27	#include <linux/freezer.h>
313d21ee	28	#include <linux/major.h>
afb5abc2 JS	29	#include "tpm.h"
	30	#include "tpm_eventlog.h"
	31
15516788 SB	32	DEFINE_IDR(dev_nums_idr);
15516788 SB	33	static DEFINE_MUTEX(idr_lock);
afb5abc2	34
313d21ee	35	struct class *tpm_class;
fdc915f7	36	struct class *tpmrm_class;
313d21ee JS	37	dev_t tpm_devt;
313d21ee JS	38
4e26195f JG	39	/**
	40	* tpm_try_get_ops() - Get a ref to the tpm_chip
	41	* @chip: Chip to ref
	42	*
	43	* The caller must already have some kind of locking to ensure that chip is
	44	* valid. This function will lock the chip so that the ops member can be
	45	* accessed safely. The locking prevents tpm_chip_unregister from
	46	* completing, so it should not be held for long periods.
	47	*
	48	* Returns -ERRNO if the chip could not be got.
afb5abc2	49	*/
4e26195f JG	50	int tpm_try_get_ops(struct tpm_chip *chip)
	51	{
	52	int rc = -EIO;
	53
	54	get_device(&chip->dev);
	55
	56	down_read(&chip->ops_sem);
	57	if (!chip->ops)
	58	goto out_lock;
	59
4e26195f JG	60	return 0;
	61	out_lock:
	62	up_read(&chip->ops_sem);
	63	put_device(&chip->dev);
	64	return rc;
	65	}
	66	EXPORT_SYMBOL_GPL(tpm_try_get_ops);
	67
	68	/**
	69	* tpm_put_ops() - Release a ref to the tpm_chip
	70	* @chip: Chip to put
	71	*
	72	* This is the opposite pair to tpm_try_get_ops(). After this returns chip may
	73	* be kfree'd.
	74	*/
	75	void tpm_put_ops(struct tpm_chip *chip)
	76	{
4e26195f JG	77	up_read(&chip->ops_sem);
	78	put_device(&chip->dev);
	79	}
	80	EXPORT_SYMBOL_GPL(tpm_put_ops);
	81
	82	/**
	83	* tpm_chip_find_get() - return tpm_chip for a given chip number
	84	* @chip_num: id to find
	85	*
	86	* The return'd chip has been tpm_try_get_ops'd and must be released via
	87	* tpm_put_ops
37f4915f	88	*/
afb5abc2 JS	89	struct tpm_chip *tpm_chip_find_get(int chip_num)
afb5abc2 JS	90	{
15516788 SB	91	struct tpm_chip chip, res = NULL;
	92	int chip_prev;
	93
	94	mutex_lock(&idr_lock);
	95
	96	if (chip_num == TPM_ANY_NUM) {
	97	chip_num = 0;
	98	do {
	99	chip_prev = chip_num;
	100	chip = idr_get_next(&dev_nums_idr, &chip_num);
	101	if (chip && !tpm_try_get_ops(chip)) {
	102	res = chip;
	103	break;
	104	}
	105	} while (chip_prev != chip_num);
	106	} else {
37f4915f	107	chip = idr_find(&dev_nums_idr, chip_num);
15516788 SB	108	if (chip && !tpm_try_get_ops(chip))
	109	res = chip;
	110	}
afb5abc2	111
15516788	112	mutex_unlock(&idr_lock);
afb5abc2	113
15516788	114	return res;
afb5abc2 JS	115	}
	116
	117	/**
313d21ee JS	118	* tpm_dev_release() - free chip memory and the device number
313d21ee JS	119	* @dev: the character device for the TPM chip
afb5abc2	120	*
313d21ee	121	* This is used as the release function for the character device.
afb5abc2	122	*/
313d21ee	123	static void tpm_dev_release(struct device *dev)
afb5abc2	124	{
313d21ee	125	struct tpm_chip *chip = container_of(dev, struct tpm_chip, dev);
afb5abc2	126
15516788 SB	127	mutex_lock(&idr_lock);
	128	idr_remove(&dev_nums_idr, chip->dev_num);
	129	mutex_unlock(&idr_lock);
	130
748935ee	131	kfree(chip->log.bios_event_log);
745b361e	132	kfree(chip->work_space.context_buf);
4d57856a	133	kfree(chip->work_space.session_buf);
afb5abc2 JS	134	kfree(chip);
	135	}
	136
fdc915f7 JB	137	static void tpm_devs_release(struct device *dev)
	138	{
	139	struct tpm_chip *chip = container_of(dev, struct tpm_chip, devs);
	140
	141	/* release the master device reference */
	142	put_device(&chip->dev);
	143	}
	144
afb5abc2	145	/**
3897cd9c JG	146	* tpm_chip_alloc() - allocate a new struct tpm_chip instance
	147	* @pdev: device to which the chip is associated
	148	* At this point pdev mst be initialized, but does not have to
	149	* be registered
afb5abc2 JS	150	* @ops: struct tpm_class_ops instance
	151	*
	152	* Allocates a new struct tpm_chip instance and assigns a free
3897cd9c	153	* device number for it. Must be paired with put_device(&chip->dev).
afb5abc2	154	*/
2998b02b	155	struct tpm_chip tpm_chip_alloc(struct device pdev,
3897cd9c	156	const struct tpm_class_ops *ops)
afb5abc2 JS	157	{
afb5abc2 JS	158	struct tpm_chip *chip;
4f3b193d	159	int rc;
afb5abc2 JS	160
	161	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
	162	if (chip == NULL)
	163	return ERR_PTR(-ENOMEM);
	164
	165	mutex_init(&chip->tpm_mutex);
4e26195f	166	init_rwsem(&chip->ops_sem);
afb5abc2 JS	167
	168	chip->ops = ops;
	169
15516788 SB	170	mutex_lock(&idr_lock);
	171	rc = idr_alloc(&dev_nums_idr, NULL, 0, TPM_NUM_DEVICES, GFP_KERNEL);
	172	mutex_unlock(&idr_lock);
	173	if (rc < 0) {
2998b02b	174	dev_err(pdev, "No available tpm device numbers\n");
afb5abc2	175	kfree(chip);
15516788	176	return ERR_PTR(rc);
afb5abc2	177	}
15516788	178	chip->dev_num = rc;
afb5abc2	179
3635e2ec	180	device_initialize(&chip->dev);
fdc915f7	181	device_initialize(&chip->devs);
afb5abc2	182
313d21ee JS	183	chip->dev.class = tpm_class;
313d21ee JS	184	chip->dev.release = tpm_dev_release;
2998b02b	185	chip->dev.parent = pdev;
9b774d5c	186	chip->dev.groups = chip->groups;
313d21ee	187
fdc915f7 JB	188	chip->devs.parent = pdev;
	189	chip->devs.class = tpmrm_class;
	190	chip->devs.release = tpm_devs_release;
	191	/* get extra reference on main device to hold on
	192	* behalf of devs. This holds the chip structure
	193	* while cdevs is in use. The corresponding put
	194	* is in the tpm_devs_release
	195	*/
	196	get_device(&chip->dev);
	197
313d21ee JS	198	if (chip->dev_num == 0)
	199	chip->dev.devt = MKDEV(MISC_MAJOR, TPM_MINOR);
	200	else
	201	chip->dev.devt = MKDEV(MAJOR(tpm_devt), chip->dev_num);
	202
fdc915f7 JB	203	chip->devs.devt =
	204	MKDEV(MAJOR(tpm_devt), chip->dev_num + TPM_NUM_DEVICES);
	205
3635e2ec	206	rc = dev_set_name(&chip->dev, "tpm%d", chip->dev_num);
fdc915f7 JB	207	if (rc)
	208	goto out;
	209	rc = dev_set_name(&chip->devs, "tpmrm%d", chip->dev_num);
3635e2ec JG	210	if (rc)
3635e2ec JG	211	goto out;
313d21ee	212
2998b02b	213	if (!pdev)
2f9f5377 SB	214	chip->flags \|= TPM_CHIP_FLAG_VIRTUAL;
2f9f5377 SB	215
313d21ee	216	cdev_init(&chip->cdev, &tpm_fops);
fdc915f7	217	cdev_init(&chip->cdevs, &tpmrm_fops);
2072df40	218	chip->cdev.owner = THIS_MODULE;
fdc915f7	219	chip->cdevs.owner = THIS_MODULE;
ba0ef854	220	chip->cdev.kobj.parent = &chip->dev.kobj;
fdc915f7	221	chip->cdevs.kobj.parent = &chip->devs.kobj;
313d21ee	222
745b361e JS	223	chip->work_space.context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
	224	if (!chip->work_space.context_buf) {
	225	rc = -ENOMEM;
	226	goto out;
	227	}
4d57856a JB	228	chip->work_space.session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
	229	if (!chip->work_space.session_buf) {
	230	rc = -ENOMEM;
	231	goto out;
	232	}
745b361e	233
3897cd9c JG	234	return chip;
	235
	236	out:
fdc915f7	237	put_device(&chip->devs);
3897cd9c JG	238	put_device(&chip->dev);
	239	return ERR_PTR(rc);
	240	}
	241	EXPORT_SYMBOL_GPL(tpm_chip_alloc);
	242
	243	/**
	244	* tpmm_chip_alloc() - allocate a new struct tpm_chip instance
	245	* @pdev: parent device to which the chip is associated
	246	* @ops: struct tpm_class_ops instance
	247	*
	248	* Same as tpm_chip_alloc except devm is used to do the put_device
	249	*/
	250	struct tpm_chip tpmm_chip_alloc(struct device pdev,
	251	const struct tpm_class_ops *ops)
	252	{
	253	struct tpm_chip *chip;
	254	int rc;
	255
	256	chip = tpm_chip_alloc(pdev, ops);
	257	if (IS_ERR(chip))
	258	return chip;
	259
2b88cd96 SM	260	rc = devm_add_action_or_reset(pdev,
	261	(void ()(void )) put_device,
	262	&chip->dev);
	263	if (rc)
4f3b193d	264	return ERR_PTR(rc);
8e0ee3c9	265
3897cd9c	266	dev_set_drvdata(pdev, chip);
3635e2ec	267
3897cd9c	268	return chip;
afb5abc2 JS	269	}
	270	EXPORT_SYMBOL_GPL(tpmm_chip_alloc);
	271
72c91ce8	272	static int tpm_add_char_device(struct tpm_chip *chip)
313d21ee JS	273	{
	274	int rc;
	275
d972b052	276	rc = cdev_add(&chip->cdev, chip->dev.devt, 1);
313d21ee JS	277	if (rc) {
313d21ee JS	278	dev_err(&chip->dev,
d972b052	279	"unable to cdev_add() %s, major %d, minor %d, err=%d\n",
3635e2ec	280	dev_name(&chip->dev), MAJOR(chip->dev.devt),
313d21ee	281	MINOR(chip->dev.devt), rc);
313d21ee JS	282	return rc;
	283	}
	284
d972b052	285	rc = device_add(&chip->dev);
313d21ee JS	286	if (rc) {
313d21ee JS	287	dev_err(&chip->dev,
d972b052	288	"unable to device_register() %s, major %d, minor %d, err=%d\n",
3635e2ec	289	dev_name(&chip->dev), MAJOR(chip->dev.devt),
313d21ee JS	290	MINOR(chip->dev.devt), rc);
313d21ee JS	291
72c91ce8	292	cdev_del(&chip->cdev);
313d21ee JS	293	return rc;
	294	}
	295
fdc915f7 JB	296	if (chip->flags & TPM_CHIP_FLAG_TPM2)
	297	rc = cdev_add(&chip->cdevs, chip->devs.devt, 1);
	298	if (rc) {
	299	dev_err(&chip->dev,
	300	"unable to cdev_add() %s, major %d, minor %d, err=%d\n",
	301	dev_name(&chip->devs), MAJOR(chip->devs.devt),
	302	MINOR(chip->devs.devt), rc);
fdc915f7 JB	303	return rc;
	304	}
	305
	306	if (chip->flags & TPM_CHIP_FLAG_TPM2)
	307	rc = device_add(&chip->devs);
	308	if (rc) {
	309	dev_err(&chip->dev,
	310	"unable to device_register() %s, major %d, minor %d, err=%d\n",
	311	dev_name(&chip->devs), MAJOR(chip->devs.devt),
	312	MINOR(chip->devs.devt), rc);
	313	cdev_del(&chip->cdevs);
fdc915f7 JB	314	return rc;
	315	}
	316
15516788 SB	317	/* Make the chip available. */
	318	mutex_lock(&idr_lock);
	319	idr_replace(&dev_nums_idr, chip, chip->dev_num);
	320	mutex_unlock(&idr_lock);
	321
313d21ee JS	322	return rc;
	323	}
	324
72c91ce8	325	static void tpm_del_char_device(struct tpm_chip *chip)
313d21ee JS	326	{
313d21ee JS	327	cdev_del(&chip->cdev);
15516788 SB	328	device_del(&chip->dev);
	329
	330	/* Make the chip unavailable. */
	331	mutex_lock(&idr_lock);
	332	idr_replace(&dev_nums_idr, NULL, chip->dev_num);
	333	mutex_unlock(&idr_lock);
4e26195f JG	334
	335	/* Make the driver uncallable. */
	336	down_write(&chip->ops_sem);
c0dff1f4 JS	337	if (chip->flags & TPM_CHIP_FLAG_TPM2)
c0dff1f4 JS	338	tpm2_shutdown(chip, TPM2_SU_CLEAR);
4e26195f JG	339	chip->ops = NULL;
4e26195f JG	340	up_write(&chip->ops_sem);
313d21ee JS	341	}
313d21ee JS	342
062807f2 JG	343	static void tpm_del_legacy_sysfs(struct tpm_chip *chip)
	344	{
	345	struct attribute **i;
	346
2f9f5377	347	if (chip->flags & (TPM_CHIP_FLAG_TPM2 \| TPM_CHIP_FLAG_VIRTUAL))
062807f2	348	return;
34d47b63	349
062807f2 JG	350	sysfs_remove_link(&chip->dev.parent->kobj, "ppi");
	351
	352	for (i = chip->groups[0]->attrs; *i != NULL; ++i)
	353	sysfs_remove_link(&chip->dev.parent->kobj, (*i)->name);
34d47b63 JS	354	}
34d47b63 JS	355
062807f2 JG	356	/* For compatibility with legacy sysfs paths we provide symlinks from the
	357	* parent dev directory to selected names within the tpm chip directory. Old
	358	* kernel versions created these files directly under the parent.
	359	*/
	360	static int tpm_add_legacy_sysfs(struct tpm_chip *chip)
	361	{
	362	struct attribute **i;
	363	int rc;
	364
2f9f5377	365	if (chip->flags & (TPM_CHIP_FLAG_TPM2 \| TPM_CHIP_FLAG_VIRTUAL))
062807f2 JG	366	return 0;
	367
	368	rc = __compat_only_sysfs_link_entry_to_kobj(
	369	&chip->dev.parent->kobj, &chip->dev.kobj, "ppi");
	370	if (rc && rc != -ENOENT)
	371	return rc;
	372
	373	/* All the names from tpm-sysfs */
	374	for (i = chip->groups[0]->attrs; *i != NULL; ++i) {
	375	rc = __compat_only_sysfs_link_entry_to_kobj(
	376	&chip->dev.parent->kobj, &chip->dev.kobj, (*i)->name);
	377	if (rc) {
	378	tpm_del_legacy_sysfs(chip);
	379	return rc;
	380	}
	381	}
	382
	383	return 0;
	384	}
afb5abc2	385	/*
313d21ee	386	* tpm_chip_register() - create a character device for the TPM chip
afb5abc2 JS	387	* @chip: TPM chip to use.
afb5abc2 JS	388	*
d972b052 JS	389	* Creates a character device for the TPM chip and adds sysfs attributes for
	390	* the device. As the last step this function adds the chip to the list of TPM
	391	* chips available for in-kernel use.
afb5abc2	392	*
d972b052 JS	393	* This function should be only called after the chip initialization is
d972b052 JS	394	* complete.
afb5abc2 JS	395	*/
	396	int tpm_chip_register(struct tpm_chip *chip)
	397	{
	398	int rc;
	399
cae8b441 JG	400	if (chip->ops->flags & TPM_OPS_AUTO_STARTUP) {
	401	if (chip->flags & TPM_CHIP_FLAG_TPM2)
	402	rc = tpm2_auto_startup(chip);
	403	else
	404	rc = tpm1_auto_startup(chip);
	405	if (rc)
	406	return rc;
	407	}
	408
7518a21a JS	409	tpm_sysfs_add_device(chip);
	410
	411	rc = tpm_bios_log_setup(chip);
0cf577a0	412	if (rc != 0 && rc != -ENODEV)
34d47b63	413	return rc;
afb5abc2	414
9b774d5c JS	415	tpm_add_ppi(chip);
9b774d5c JS	416
72c91ce8	417	rc = tpm_add_char_device(chip);
062807f2	418	if (rc) {
7518a21a	419	tpm_bios_log_teardown(chip);
062807f2 JG	420	return rc;
062807f2 JG	421	}
d972b052	422
062807f2 JG	423	rc = tpm_add_legacy_sysfs(chip);
	424	if (rc) {
	425	tpm_chip_unregister(chip);
	426	return rc;
d56e4f75 JS	427	}
d56e4f75 JS	428
afb5abc2	429	return 0;
afb5abc2 JS	430	}
	431	EXPORT_SYMBOL_GPL(tpm_chip_register);
	432
	433	/*
	434	* tpm_chip_unregister() - release the TPM driver
	435	* @chip: TPM chip to use.
	436	*
	437	* Takes the chip first away from the list of available TPM chips and then
	438	* cleans up all the resources reserved by tpm_chip_register().
	439	*
4e26195f JG	440	* Once this function returns the driver call backs in 'op's will not be
	441	* running and will no longer start.
	442	*
afb5abc2 JS	443	* NOTE: This function should be only called before deinitializing chip
	444	* resources.
	445	*/
	446	void tpm_chip_unregister(struct tpm_chip *chip)
	447	{
062807f2	448	tpm_del_legacy_sysfs(chip);
7518a21a	449	tpm_bios_log_teardown(chip);
fdc915f7 JB	450	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
	451	cdev_del(&chip->cdevs);
	452	device_del(&chip->devs);
	453	}
72c91ce8	454	tpm_del_char_device(chip);
afb5abc2 JS	455	}
afb5abc2 JS	456	EXPORT_SYMBOL_GPL(tpm_chip_unregister);