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 #include "tpm_atmel.h"
24
25 /* write status bits */
26 enum tpm_atmel_write_status {
27 ATML_STATUS_ABORT = 0x01,
28 ATML_STATUS_LASTBYTE = 0x04
29 };
30 /* read status bits */
31 enum tpm_atmel_read_status {
32 ATML_STATUS_BUSY = 0x01,
33 ATML_STATUS_DATA_AVAIL = 0x02,
34 ATML_STATUS_REWRITE = 0x04,
35 ATML_STATUS_READY = 0x08
36 };
37
tpm_atml_recv(struct tpm_chip * chip,u8 * buf,size_t count)38 static int tpm_atml_recv(struct tpm_chip *chip, u8 *buf, size_t count)
39 {
40 u8 status, *hdr = buf;
41 u32 size;
42 int i;
43 __be32 *native_size;
44
45 /* start reading header */
46 if (count < 6)
47 return -EIO;
48
49 for (i = 0; i < 6; i++) {
50 status = ioread8(chip->vendor.iobase + 1);
51 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
52 dev_err(chip->dev, "error reading header\n");
53 return -EIO;
54 }
55 *buf++ = ioread8(chip->vendor.iobase);
56 }
57
58 /* size of the data received */
59 native_size = (__force __be32 *) (hdr + 2);
60 size = be32_to_cpu(*native_size);
61
62 if (count < size) {
63 dev_err(chip->dev,
64 "Recv size(%d) less than available space\n", size);
65 for (; i < size; i++) { /* clear the waiting data anyway */
66 status = ioread8(chip->vendor.iobase + 1);
67 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
68 dev_err(chip->dev, "error reading data\n");
69 return -EIO;
70 }
71 }
72 return -EIO;
73 }
74
75 /* read all the data available */
76 for (; i < size; i++) {
77 status = ioread8(chip->vendor.iobase + 1);
78 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
79 dev_err(chip->dev, "error reading data\n");
80 return -EIO;
81 }
82 *buf++ = ioread8(chip->vendor.iobase);
83 }
84
85 /* make sure data available is gone */
86 status = ioread8(chip->vendor.iobase + 1);
87
88 if (status & ATML_STATUS_DATA_AVAIL) {
89 dev_err(chip->dev, "data available is stuck\n");
90 return -EIO;
91 }
92
93 return size;
94 }
95
tpm_atml_send(struct tpm_chip * chip,u8 * buf,size_t count)96 static int tpm_atml_send(struct tpm_chip *chip, u8 *buf, size_t count)
97 {
98 int i;
99
100 dev_dbg(chip->dev, "tpm_atml_send:\n");
101 for (i = 0; i < count; i++) {
102 dev_dbg(chip->dev, "%d 0x%x(%d)\n", i, buf[i], buf[i]);
103 iowrite8(buf[i], chip->vendor.iobase);
104 }
105
106 return count;
107 }
108
tpm_atml_cancel(struct tpm_chip * chip)109 static void tpm_atml_cancel(struct tpm_chip *chip)
110 {
111 iowrite8(ATML_STATUS_ABORT, chip->vendor.iobase + 1);
112 }
113
tpm_atml_status(struct tpm_chip * chip)114 static u8 tpm_atml_status(struct tpm_chip *chip)
115 {
116 return ioread8(chip->vendor.iobase + 1);
117 }
118
119 static const struct file_operations atmel_ops = {
120 .owner = THIS_MODULE,
121 .llseek = no_llseek,
122 .open = tpm_open,
123 .read = tpm_read,
124 .write = tpm_write,
125 .release = tpm_release,
126 };
127
128 static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
129 static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
130 static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
131 static DEVICE_ATTR(cancel, S_IWUSR |S_IWGRP, NULL, tpm_store_cancel);
132
133 static struct attribute* atmel_attrs[] = {
134 &dev_attr_pubek.attr,
135 &dev_attr_pcrs.attr,
136 &dev_attr_caps.attr,
137 &dev_attr_cancel.attr,
138 NULL,
139 };
140
141 static struct attribute_group atmel_attr_grp = { .attrs = atmel_attrs };
142
143 static const struct tpm_vendor_specific tpm_atmel = {
144 .recv = tpm_atml_recv,
145 .send = tpm_atml_send,
146 .cancel = tpm_atml_cancel,
147 .status = tpm_atml_status,
148 .req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL,
149 .req_complete_val = ATML_STATUS_DATA_AVAIL,
150 .req_canceled = ATML_STATUS_READY,
151 .attr_group = &atmel_attr_grp,
152 .miscdev = { .fops = &atmel_ops, },
153 };
154
155 static struct platform_device *pdev;
156
atml_plat_remove(void)157 static void atml_plat_remove(void)
158 {
159 struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
160
161 if (chip) {
162 if (chip->vendor.have_region)
163 atmel_release_region(chip->vendor.base,
164 chip->vendor.region_size);
165 atmel_put_base_addr(chip->vendor.iobase);
166 tpm_remove_hardware(chip->dev);
167 platform_device_unregister(pdev);
168 }
169 }
170
171 static struct device_driver atml_drv = {
172 .name = "tpm_atmel",
173 .bus = &platform_bus_type,
174 .owner = THIS_MODULE,
175 .suspend = tpm_pm_suspend,
176 .resume = tpm_pm_resume,
177 };
178
init_atmel(void)179 static int __init init_atmel(void)
180 {
181 int rc = 0;
182 void __iomem *iobase = NULL;
183 int have_region, region_size;
184 unsigned long base;
185 struct tpm_chip *chip;
186
187 rc = driver_register(&atml_drv);
188 if (rc)
189 return rc;
190
191 if ((iobase = atmel_get_base_addr(&base, ®ion_size)) == NULL) {
192 rc = -ENODEV;
193 goto err_unreg_drv;
194 }
195
196 have_region =
197 (atmel_request_region
198 (tpm_atmel.base, region_size, "tpm_atmel0") == NULL) ? 0 : 1;
199
200 pdev = platform_device_register_simple("tpm_atmel", -1, NULL, 0);
201 if (IS_ERR(pdev)) {
202 rc = PTR_ERR(pdev);
203 goto err_rel_reg;
204 }
205
206 if (!(chip = tpm_register_hardware(&pdev->dev, &tpm_atmel))) {
207 rc = -ENODEV;
208 goto err_unreg_dev;
209 }
210
211 chip->vendor.iobase = iobase;
212 chip->vendor.base = base;
213 chip->vendor.have_region = have_region;
214 chip->vendor.region_size = region_size;
215
216 return 0;
217
218 err_unreg_dev:
219 platform_device_unregister(pdev);
220 err_rel_reg:
221 atmel_put_base_addr(iobase);
222 if (have_region)
223 atmel_release_region(base,
224 region_size);
225 err_unreg_drv:
226 driver_unregister(&atml_drv);
227 return rc;
228 }
229
cleanup_atmel(void)230 static void __exit cleanup_atmel(void)
231 {
232 driver_unregister(&atml_drv);
233 atml_plat_remove();
234 }
235
236 module_init(init_atmel);
237 module_exit(cleanup_atmel);
238
239 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
240 MODULE_DESCRIPTION("TPM Driver");
241 MODULE_VERSION("2.0");
242 MODULE_LICENSE("GPL");
243