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 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
41 u8 status, *hdr = buf;
42 u32 size;
43 int i;
44 __be32 *native_size;
45
46 /* start reading header */
47 if (count < 6)
48 return -EIO;
49
50 for (i = 0; i < 6; i++) {
51 status = ioread8(priv->iobase + 1);
52 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
53 dev_err(&chip->dev, "error reading header\n");
54 return -EIO;
55 }
56 *buf++ = ioread8(priv->iobase);
57 }
58
59 /* size of the data received */
60 native_size = (__force __be32 *) (hdr + 2);
61 size = be32_to_cpu(*native_size);
62
63 if (count < size) {
64 dev_err(&chip->dev,
65 "Recv size(%d) less than available space\n", size);
66 for (; i < size; i++) { /* clear the waiting data anyway */
67 status = ioread8(priv->iobase + 1);
68 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
69 dev_err(&chip->dev, "error reading data\n");
70 return -EIO;
71 }
72 }
73 return -EIO;
74 }
75
76 /* read all the data available */
77 for (; i < size; i++) {
78 status = ioread8(priv->iobase + 1);
79 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
80 dev_err(&chip->dev, "error reading data\n");
81 return -EIO;
82 }
83 *buf++ = ioread8(priv->iobase);
84 }
85
86 /* make sure data available is gone */
87 status = ioread8(priv->iobase + 1);
88
89 if (status & ATML_STATUS_DATA_AVAIL) {
90 dev_err(&chip->dev, "data available is stuck\n");
91 return -EIO;
92 }
93
94 return size;
95 }
96
tpm_atml_send(struct tpm_chip * chip,u8 * buf,size_t count)97 static int tpm_atml_send(struct tpm_chip *chip, u8 *buf, size_t count)
98 {
99 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
100 int i;
101
102 dev_dbg(&chip->dev, "tpm_atml_send:\n");
103 for (i = 0; i < count; i++) {
104 dev_dbg(&chip->dev, "%d 0x%x(%d)\n", i, buf[i], buf[i]);
105 iowrite8(buf[i], priv->iobase);
106 }
107
108 return count;
109 }
110
tpm_atml_cancel(struct tpm_chip * chip)111 static void tpm_atml_cancel(struct tpm_chip *chip)
112 {
113 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
114
115 iowrite8(ATML_STATUS_ABORT, priv->iobase + 1);
116 }
117
tpm_atml_status(struct tpm_chip * chip)118 static u8 tpm_atml_status(struct tpm_chip *chip)
119 {
120 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
121
122 return ioread8(priv->iobase + 1);
123 }
124
tpm_atml_req_canceled(struct tpm_chip * chip,u8 status)125 static bool tpm_atml_req_canceled(struct tpm_chip *chip, u8 status)
126 {
127 return (status == ATML_STATUS_READY);
128 }
129
130 static const struct tpm_class_ops tpm_atmel = {
131 .recv = tpm_atml_recv,
132 .send = tpm_atml_send,
133 .cancel = tpm_atml_cancel,
134 .status = tpm_atml_status,
135 .req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL,
136 .req_complete_val = ATML_STATUS_DATA_AVAIL,
137 .req_canceled = tpm_atml_req_canceled,
138 };
139
140 static struct platform_device *pdev;
141
atml_plat_remove(void)142 static void atml_plat_remove(void)
143 {
144 struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
145 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
146
147 tpm_chip_unregister(chip);
148 if (priv->have_region)
149 atmel_release_region(priv->base, priv->region_size);
150 atmel_put_base_addr(priv->iobase);
151 platform_device_unregister(pdev);
152 }
153
154 static SIMPLE_DEV_PM_OPS(tpm_atml_pm, tpm_pm_suspend, tpm_pm_resume);
155
156 static struct platform_driver atml_drv = {
157 .driver = {
158 .name = "tpm_atmel",
159 .pm = &tpm_atml_pm,
160 },
161 };
162
init_atmel(void)163 static int __init init_atmel(void)
164 {
165 int rc = 0;
166 void __iomem *iobase = NULL;
167 int have_region, region_size;
168 unsigned long base;
169 struct tpm_chip *chip;
170 struct tpm_atmel_priv *priv;
171
172 rc = platform_driver_register(&atml_drv);
173 if (rc)
174 return rc;
175
176 if ((iobase = atmel_get_base_addr(&base, ®ion_size)) == NULL) {
177 rc = -ENODEV;
178 goto err_unreg_drv;
179 }
180
181 have_region =
182 (atmel_request_region
183 (base, region_size, "tpm_atmel0") == NULL) ? 0 : 1;
184
185 pdev = platform_device_register_simple("tpm_atmel", -1, NULL, 0);
186 if (IS_ERR(pdev)) {
187 rc = PTR_ERR(pdev);
188 goto err_rel_reg;
189 }
190
191 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
192 if (!priv) {
193 rc = -ENOMEM;
194 goto err_unreg_dev;
195 }
196
197 priv->iobase = iobase;
198 priv->base = base;
199 priv->have_region = have_region;
200 priv->region_size = region_size;
201
202 chip = tpmm_chip_alloc(&pdev->dev, &tpm_atmel);
203 if (IS_ERR(chip)) {
204 rc = PTR_ERR(chip);
205 goto err_unreg_dev;
206 }
207
208 dev_set_drvdata(&chip->dev, priv);
209
210 rc = tpm_chip_register(chip);
211 if (rc)
212 goto err_unreg_dev;
213
214 return 0;
215
216 err_unreg_dev:
217 platform_device_unregister(pdev);
218 err_rel_reg:
219 atmel_put_base_addr(iobase);
220 if (have_region)
221 atmel_release_region(base,
222 region_size);
223 err_unreg_drv:
224 platform_driver_unregister(&atml_drv);
225 return rc;
226 }
227
cleanup_atmel(void)228 static void __exit cleanup_atmel(void)
229 {
230 platform_driver_unregister(&atml_drv);
231 atml_plat_remove();
232 }
233
234 module_init(init_atmel);
235 module_exit(cleanup_atmel);
236
237 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
238 MODULE_DESCRIPTION("TPM Driver");
239 MODULE_VERSION("2.0");
240 MODULE_LICENSE("GPL");
241
