tpm_atmel.c 5.17 KB
Newer Older
Linus Torvalds's avatar
Linus Torvalds committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
/*
 * Copyright (C) 2004 IBM Corporation
 *
 * Authors:
 * 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>
 *
 * Device driver for TCG/TCPA TPM (trusted platform module).
 * Specifications at www.trustedcomputinggroup.org	 
 *
 * 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 "tpm.h"
23
#include "tpm_atmel.h"
Linus Torvalds's avatar
Linus Torvalds committed
24 25

/* write status bits */
26 27 28 29
enum tpm_atmel_write_status {
	ATML_STATUS_ABORT = 0x01,
	ATML_STATUS_LASTBYTE = 0x04
};
Linus Torvalds's avatar
Linus Torvalds committed
30
/* read status bits */
31 32 33 34 35 36
enum tpm_atmel_read_status {
	ATML_STATUS_BUSY = 0x01,
	ATML_STATUS_DATA_AVAIL = 0x02,
	ATML_STATUS_REWRITE = 0x04,
	ATML_STATUS_READY = 0x08
};
Linus Torvalds's avatar
Linus Torvalds committed
37

Andrew Morton's avatar
Andrew Morton committed
38
static int tpm_atml_recv(struct tpm_chip *chip, u8 *buf, size_t count)
Linus Torvalds's avatar
Linus Torvalds committed
39 40 41 42 43 44 45 46 47 48 49
{
	u8 status, *hdr = buf;
	u32 size;
	int i;
	__be32 *native_size;

	/* start reading header */
	if (count < 6)
		return -EIO;

	for (i = 0; i < 6; i++) {
50
		status = atmel_getb(chip, 1);
Linus Torvalds's avatar
Linus Torvalds committed
51
		if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
52
			dev_err(chip->dev,
Linus Torvalds's avatar
Linus Torvalds committed
53 54 55
				"error reading header\n");
			return -EIO;
		}
56
		*buf++ = atmel_getb(chip, 0);
Linus Torvalds's avatar
Linus Torvalds committed
57 58 59 60 61 62 63
	}

	/* size of the data received */
	native_size = (__force __be32 *) (hdr + 2);
	size = be32_to_cpu(*native_size);

	if (count < size) {
64
		dev_err(chip->dev,
Linus Torvalds's avatar
Linus Torvalds committed
65 66
			"Recv size(%d) less than available space\n", size);
		for (; i < size; i++) {	/* clear the waiting data anyway */
67
			status = atmel_getb(chip, 1);
Linus Torvalds's avatar
Linus Torvalds committed
68
			if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
69
				dev_err(chip->dev,
Linus Torvalds's avatar
Linus Torvalds committed
70 71 72 73 74 75 76 77 78
					"error reading data\n");
				return -EIO;
			}
		}
		return -EIO;
	}

	/* read all the data available */
	for (; i < size; i++) {
79
		status = atmel_getb(chip, 1);
Linus Torvalds's avatar
Linus Torvalds committed
80
		if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
81
			dev_err(chip->dev,
Linus Torvalds's avatar
Linus Torvalds committed
82 83 84
				"error reading data\n");
			return -EIO;
		}
85
		*buf++ = atmel_getb(chip, 0);
Linus Torvalds's avatar
Linus Torvalds committed
86 87 88
	}

	/* make sure data available is gone */
89
	status = atmel_getb(chip, 1);
Linus Torvalds's avatar
Linus Torvalds committed
90
	if (status & ATML_STATUS_DATA_AVAIL) {
91
		dev_err(chip->dev, "data available is stuck\n");
Linus Torvalds's avatar
Linus Torvalds committed
92 93 94 95 96 97
		return -EIO;
	}

	return size;
}

Andrew Morton's avatar
Andrew Morton committed
98
static int tpm_atml_send(struct tpm_chip *chip, u8 *buf, size_t count)
Linus Torvalds's avatar
Linus Torvalds committed
99 100 101
{
	int i;

102
	dev_dbg(chip->dev, "tpm_atml_send:\n");
Linus Torvalds's avatar
Linus Torvalds committed
103
	for (i = 0; i < count; i++) {
104
		dev_dbg(chip->dev, "%d 0x%x(%d)\n",  i, buf[i], buf[i]);
105
		atmel_putb(buf[i], chip, 0);
Linus Torvalds's avatar
Linus Torvalds committed
106 107 108 109 110 111 112
	}

	return count;
}

static void tpm_atml_cancel(struct tpm_chip *chip)
{
113
	atmel_putb(ATML_STATUS_ABORT, chip, 1);
Linus Torvalds's avatar
Linus Torvalds committed
114 115
}

116 117
static u8 tpm_atml_status(struct tpm_chip *chip)
{
118
	return atmel_getb(chip, 1);
119 120
}

Linus Torvalds's avatar
Linus Torvalds committed
121 122 123 124 125 126 127 128 129
static struct file_operations atmel_ops = {
	.owner = THIS_MODULE,
	.llseek = no_llseek,
	.open = tpm_open,
	.read = tpm_read,
	.write = tpm_write,
	.release = tpm_release,
};

130 131 132 133 134 135 136 137 138 139
static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
static DEVICE_ATTR(cancel, S_IWUSR |S_IWGRP, NULL, tpm_store_cancel);

static struct attribute* atmel_attrs[] = {
	&dev_attr_pubek.attr,
	&dev_attr_pcrs.attr,
	&dev_attr_caps.attr,
	&dev_attr_cancel.attr,
140
	NULL,
141 142 143 144
};

static struct attribute_group atmel_attr_grp = { .attrs = atmel_attrs };

Linus Torvalds's avatar
Linus Torvalds committed
145 146 147 148
static struct tpm_vendor_specific tpm_atmel = {
	.recv = tpm_atml_recv,
	.send = tpm_atml_send,
	.cancel = tpm_atml_cancel,
149
	.status = tpm_atml_status,
Linus Torvalds's avatar
Linus Torvalds committed
150 151
	.req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL,
	.req_complete_val = ATML_STATUS_DATA_AVAIL,
152
	.req_canceled = ATML_STATUS_READY,
153
	.attr_group = &atmel_attr_grp,
Linus Torvalds's avatar
Linus Torvalds committed
154 155 156
	.miscdev = { .fops = &atmel_ops, },
};

Andrew Morton's avatar
Andrew Morton committed
157
static struct platform_device *pdev;
158

159
static void atml_plat_remove(void)
160
{
161 162
	struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);

Andrew Morton's avatar
Andrew Morton committed
163
	if (chip) {
164 165 166
		if (chip->vendor->have_region)
			atmel_release_region(chip->vendor->base, chip->vendor->region_size);
		atmel_put_base_addr(chip->vendor);
167
		tpm_remove_hardware(chip->dev);
168
		platform_device_unregister(pdev);
169 170 171 172 173 174 175 176 177 178 179 180
	}
}

static struct device_driver atml_drv = {
	.name = "tpm_atmel",
	.bus = &platform_bus_type,
	.owner = THIS_MODULE,
	.suspend = tpm_pm_suspend,
	.resume = tpm_pm_resume,
};

static int __init init_atmel(void)
Linus Torvalds's avatar
Linus Torvalds committed
181 182 183
{
	int rc = 0;

184
	driver_register(&atml_drv);
Linus Torvalds's avatar
Linus Torvalds committed
185

186 187 188
	if (atmel_get_base_addr(&tpm_atmel) != 0) {
		rc = -ENODEV;
		goto err_unreg_drv;
189
	}
Linus Torvalds's avatar
Linus Torvalds committed
190

191
	tpm_atmel.have_region = (atmel_request_region( tpm_atmel.base, tpm_atmel.region_size, "tpm_atmel0") == NULL) ? 0 : 1;
Linus Torvalds's avatar
Linus Torvalds committed
192

193 194 195
	if (IS_ERR(pdev = platform_device_register_simple("tpm_atmel", -1, NULL, 0 ))) {
		rc = PTR_ERR(pdev);
		goto err_rel_reg;
196
	}
Linus Torvalds's avatar
Linus Torvalds committed
197

198 199
	if ((rc = tpm_register_hardware(&pdev->dev, &tpm_atmel)) < 0)
		goto err_unreg_dev;
200
	return 0;
201 202 203 204 205 206 207 208 209 210

err_unreg_dev:
	platform_device_unregister(pdev);
err_rel_reg:
	if (tpm_atmel.have_region)
		atmel_release_region(tpm_atmel.base, tpm_atmel.region_size);
	atmel_put_base_addr(&tpm_atmel);
err_unreg_drv:
	driver_unregister(&atml_drv);
	return rc;
Linus Torvalds's avatar
Linus Torvalds committed
211 212 213 214
}

static void __exit cleanup_atmel(void)
{
215
	driver_unregister(&atml_drv);
216
	atml_plat_remove();
Linus Torvalds's avatar
Linus Torvalds committed
217 218 219 220 221 222 223 224 225
}

module_init(init_atmel);
module_exit(cleanup_atmel);

MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
MODULE_DESCRIPTION("TPM Driver");
MODULE_VERSION("2.0");
MODULE_LICENSE("GPL");