1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
new file mode 100644
index 000000000000..e096e9cddb40
--- /dev/null
+++ b/drivers/char/tpm/tpm-chip.c
@@ -0,0 +1,250 @@
+/*
+ * 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"
+
+static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
+static LIST_HEAD(tpm_chip_list);
+static DEFINE_SPINLOCK(driver_lock);
+
+struct class *tpm_class;
+dev_t tpm_devt;
+
+/*
+ * tpm_chip_find_get - return tpm_chip for a given chip number
+ * @chip_num the device number for the chip
+ */
+struct tpm_chip *tpm_chip_find_get(int chip_num)
+{
+	struct tpm_chip *pos, *chip = NULL;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
+		if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
+			continue;
+
+		if (try_module_get(pos->pdev->driver->owner)) {
+			chip = pos;
+			break;
+		}
+	}
+	rcu_read_unlock();
+	return chip;
+}
+
+/**
+ * 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);
+
+	spin_lock(&driver_lock);
+	clear_bit(chip->dev_num, dev_mask);
+	spin_unlock(&driver_lock);
+	kfree(chip);
+}
+
+/**
+ * tpmm_chip_alloc() - allocate a new struct tpm_chip instance
+ * @dev: device to which the chip is associated
+ * @ops: struct tpm_class_ops instance
+ *
+ * Allocates a new struct tpm_chip instance and assigns a free
+ * device number for it. Caller does not have to worry about
+ * freeing the allocated resources. When the devices is removed
+ * devres calls tpmm_chip_remove() to do the job.
+ */
+struct tpm_chip *tpmm_chip_alloc(struct device *dev,
+				 const struct tpm_class_ops *ops)
+{
+	struct tpm_chip *chip;
+
+	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+	if (chip == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	mutex_init(&chip->tpm_mutex);
+	INIT_LIST_HEAD(&chip->list);
+
+	chip->ops = ops;
+
+	spin_lock(&driver_lock);
+	chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
+	spin_unlock(&driver_lock);
+
+	if (chip->dev_num >= TPM_NUM_DEVICES) {
+		dev_err(dev, "No available tpm device numbers\n");
+		kfree(chip);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	set_bit(chip->dev_num, dev_mask);
+
+	scnprintf(chip->devname, sizeof(chip->devname), "tpm%d", chip->dev_num);
+
+	chip->pdev = dev;
+
+	dev_set_drvdata(dev, chip);
+
+	chip->dev.class = tpm_class;
+	chip->dev.release = tpm_dev_release;
+	chip->dev.parent = chip->pdev;
+
+	if (chip->dev_num == 0)
+		chip->dev.devt = MKDEV(MISC_MAJOR, TPM_MINOR);
+	else
+		chip->dev.devt = MKDEV(MAJOR(tpm_devt), chip->dev_num);
+
+	dev_set_name(&chip->dev, "%s", chip->devname);
+
+	device_initialize(&chip->dev);
+
+	chip->cdev.owner = chip->pdev->driver->owner;
+	cdev_init(&chip->cdev, &tpm_fops);
+
+	return chip;
+}
+EXPORT_SYMBOL_GPL(tpmm_chip_alloc);
+
+static int tpm_dev_add_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",
+			chip->devname, MAJOR(chip->dev.devt),
+			MINOR(chip->dev.devt), rc);
+
+		device_unregister(&chip->dev);
+		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",
+			chip->devname, MAJOR(chip->dev.devt),
+			MINOR(chip->dev.devt), rc);
+
+		return rc;
+	}
+
+	return rc;
+}
+
+static void tpm_dev_del_device(struct tpm_chip *chip)
+{
+	cdev_del(&chip->cdev);
+	device_unregister(&chip->dev);
+}
+
+/*
+ * 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;
+
+	/* Populate sysfs for TPM1 devices. */
+	if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
+		rc = tpm_sysfs_add_device(chip);
+		if (rc)
+			goto del_misc;
+
+		rc = tpm_add_ppi(chip);
+		if (rc)
+			goto del_sysfs;
+
+		chip->bios_dir = tpm_bios_log_setup(chip->devname);
+	}
+
+	rc = tpm_dev_add_device(chip);
+	if (rc)
+		return rc;
+
+	/* Make the chip available. */
+	spin_lock(&driver_lock);
+	list_add_rcu(&chip->list, &tpm_chip_list);
+	spin_unlock(&driver_lock);
+
+	chip->flags |= TPM_CHIP_FLAG_REGISTERED;
+
+	return 0;
+del_sysfs:
+	tpm_sysfs_del_device(chip);
+del_misc:
+	tpm_dev_del_device(chip);
+	return rc;
+}
+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().
+ *
+ * NOTE: This function should be only called before deinitializing chip
+ * resources.
+ */
+void tpm_chip_unregister(struct tpm_chip *chip)
+{
+	if (!(chip->flags & TPM_CHIP_FLAG_REGISTERED))
+		return;
+
+	spin_lock(&driver_lock);
+	list_del_rcu(&chip->list);
+	spin_unlock(&driver_lock);
+	synchronize_rcu();
+
+	if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
+		if (chip->bios_dir)
+			tpm_bios_log_teardown(chip->bios_dir);
+		tpm_remove_ppi(chip);
+		tpm_sysfs_del_device(chip);
+	}
+
+	tpm_dev_del_device(chip);
+}
+EXPORT_SYMBOL_GPL(tpm_chip_unregister);