[PATCH] tpm-tidies
[linux-2.6] / drivers / char / tpm / tpm_atmel.c
1 /*
2  * Copyright (C) 2004 IBM Corporation
3  *
4  * Authors:
5  * Leendert van Doorn <leendert@watson.ibm.com>
6  * Dave Safford <safford@watson.ibm.com>
7  * Reiner Sailer <sailer@watson.ibm.com>
8  * Kylene Hall <kjhall@us.ibm.com>
9  *
10  * Maintained by: <tpmdd_devel@lists.sourceforge.net>
11  *
12  * Device driver for TCG/TCPA TPM (trusted platform module).
13  * Specifications at www.trustedcomputinggroup.org       
14  *
15  * This program is free software; you can redistribute it and/or
16  * modify it under the terms of the GNU General Public License as
17  * published by the Free Software Foundation, version 2 of the
18  * License.
19  * 
20  */
21
22 #include "tpm.h"
23
24 /* Atmel definitions */
25 enum tpm_atmel_addr {
26         TPM_ATMEL_BASE_ADDR_LO = 0x08,
27         TPM_ATMEL_BASE_ADDR_HI = 0x09
28 };
29
30 /* write status bits */
31 enum tpm_atmel_write_status {
32         ATML_STATUS_ABORT = 0x01,
33         ATML_STATUS_LASTBYTE = 0x04
34 };
35 /* read status bits */
36 enum tpm_atmel_read_status {
37         ATML_STATUS_BUSY = 0x01,
38         ATML_STATUS_DATA_AVAIL = 0x02,
39         ATML_STATUS_REWRITE = 0x04,
40         ATML_STATUS_READY = 0x08
41 };
42
43 static int tpm_atml_recv(struct tpm_chip *chip, u8 *buf, size_t count)
44 {
45         u8 status, *hdr = buf;
46         u32 size;
47         int i;
48         __be32 *native_size;
49
50         /* start reading header */
51         if (count < 6)
52                 return -EIO;
53
54         for (i = 0; i < 6; i++) {
55                 status = inb(chip->vendor->base + 1);
56                 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
57                         dev_err(chip->dev,
58                                 "error reading header\n");
59                         return -EIO;
60                 }
61                 *buf++ = inb(chip->vendor->base);
62         }
63
64         /* size of the data received */
65         native_size = (__force __be32 *) (hdr + 2);
66         size = be32_to_cpu(*native_size);
67
68         if (count < size) {
69                 dev_err(chip->dev,
70                         "Recv size(%d) less than available space\n", size);
71                 for (; i < size; i++) { /* clear the waiting data anyway */
72                         status = inb(chip->vendor->base + 1);
73                         if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
74                                 dev_err(chip->dev,
75                                         "error reading data\n");
76                                 return -EIO;
77                         }
78                 }
79                 return -EIO;
80         }
81
82         /* read all the data available */
83         for (; i < size; i++) {
84                 status = inb(chip->vendor->base + 1);
85                 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
86                         dev_err(chip->dev,
87                                 "error reading data\n");
88                         return -EIO;
89                 }
90                 *buf++ = inb(chip->vendor->base);
91         }
92
93         /* make sure data available is gone */
94         status = inb(chip->vendor->base + 1);
95         if (status & ATML_STATUS_DATA_AVAIL) {
96                 dev_err(chip->dev, "data available is stuck\n");
97                 return -EIO;
98         }
99
100         return size;
101 }
102
103 static int tpm_atml_send(struct tpm_chip *chip, u8 *buf, size_t count)
104 {
105         int i;
106
107         dev_dbg(chip->dev, "tpm_atml_send:\n");
108         for (i = 0; i < count; i++) {
109                 dev_dbg(chip->dev, "%d 0x%x(%d)\n",  i, buf[i], buf[i]);
110                 outb(buf[i], chip->vendor->base);
111         }
112
113         return count;
114 }
115
116 static void tpm_atml_cancel(struct tpm_chip *chip)
117 {
118         outb(ATML_STATUS_ABORT, chip->vendor->base + 1);
119 }
120
121 static u8 tpm_atml_status(struct tpm_chip *chip)
122 {
123         return inb(chip->vendor->base + 1);
124 }
125
126 static struct file_operations atmel_ops = {
127         .owner = THIS_MODULE,
128         .llseek = no_llseek,
129         .open = tpm_open,
130         .read = tpm_read,
131         .write = tpm_write,
132         .release = tpm_release,
133 };
134
135 static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
136 static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
137 static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
138 static DEVICE_ATTR(cancel, S_IWUSR |S_IWGRP, NULL, tpm_store_cancel);
139
140 static struct attribute* atmel_attrs[] = {
141         &dev_attr_pubek.attr,
142         &dev_attr_pcrs.attr,
143         &dev_attr_caps.attr,
144         &dev_attr_cancel.attr,
145         0,
146 };
147
148 static struct attribute_group atmel_attr_grp = { .attrs = atmel_attrs };
149
150 static struct tpm_vendor_specific tpm_atmel = {
151         .recv = tpm_atml_recv,
152         .send = tpm_atml_send,
153         .cancel = tpm_atml_cancel,
154         .status = tpm_atml_status,
155         .req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL,
156         .req_complete_val = ATML_STATUS_DATA_AVAIL,
157         .req_canceled = ATML_STATUS_READY,
158         .attr_group = &atmel_attr_grp,
159         .miscdev = { .fops = &atmel_ops, },
160 };
161
162 static struct platform_device *pdev;
163
164 static void __devexit tpm_atml_remove(struct device *dev)
165 {
166         struct tpm_chip *chip = dev_get_drvdata(dev);
167         if (chip) {
168                 release_region(chip->vendor->base, 2);
169                 tpm_remove_hardware(chip->dev);
170         }
171 }
172
173 static struct device_driver atml_drv = {
174         .name = "tpm_atmel",
175         .bus = &platform_bus_type,
176         .owner = THIS_MODULE,
177         .suspend = tpm_pm_suspend,
178         .resume = tpm_pm_resume,
179 };
180
181 static int __init init_atmel(void)
182 {
183         int rc = 0;
184         int lo, hi;
185
186         driver_register(&atml_drv);
187
188         lo = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_LO);
189         hi = tpm_read_index(TPM_ADDR, TPM_ATMEL_BASE_ADDR_HI);
190
191         tpm_atmel.base = (hi<<8)|lo;
192
193         /* verify that it is an Atmel part */
194         if (tpm_read_index(TPM_ADDR, 4) != 'A' || tpm_read_index(TPM_ADDR, 5) != 'T'
195             || tpm_read_index(TPM_ADDR, 6) != 'M' || tpm_read_index(TPM_ADDR, 7) != 'L') {
196                 return -ENODEV;
197         }
198
199         /* verify chip version number is 1.1 */
200         if (    (tpm_read_index(TPM_ADDR, 0x00) != 0x01) ||
201                 (tpm_read_index(TPM_ADDR, 0x01) != 0x01 ))
202                 return -ENODEV;
203
204         pdev = kzalloc(sizeof(struct platform_device), GFP_KERNEL);
205         if ( !pdev )
206                 return -ENOMEM;
207
208         pdev->name = "tpm_atmel0";
209         pdev->id = -1;
210         pdev->num_resources = 0;
211         pdev->dev.release = tpm_atml_remove;
212         pdev->dev.driver = &atml_drv;
213
214         if ((rc = platform_device_register(pdev)) < 0) {
215                 kfree(pdev);
216                 pdev = NULL;
217                 return rc;
218         }
219
220         if (request_region(tpm_atmel.base, 2, "tpm_atmel0") == NULL ) {
221                 platform_device_unregister(pdev);
222                 kfree(pdev);
223                 pdev = NULL;
224                 return -EBUSY;
225         }
226
227         if ((rc = tpm_register_hardware(&pdev->dev, &tpm_atmel)) < 0) {
228                 release_region(tpm_atmel.base, 2);
229                 platform_device_unregister(pdev);
230                 kfree(pdev);
231                 pdev = NULL;
232                 return rc;
233         }
234
235         dev_info(&pdev->dev, "Atmel TPM 1.1, Base Address: 0x%x\n",
236                         tpm_atmel.base);
237         return 0;
238 }
239
240 static void __exit cleanup_atmel(void)
241 {
242         if (pdev) {
243                 tpm_atml_remove(&pdev->dev);
244                 platform_device_unregister(pdev);
245                 kfree(pdev);
246                 pdev = NULL;
247         }
248
249         driver_unregister(&atml_drv);
250 }
251
252 module_init(init_atmel);
253 module_exit(cleanup_atmel);
254
255 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
256 MODULE_DESCRIPTION("TPM Driver");
257 MODULE_VERSION("2.0");
258 MODULE_LICENSE("GPL");