Linux kernel & device driver programming

Cross-Referenced Linux and Device Driver Code

[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ]
Version: [ 2.6.11.8 ] [ 2.6.25 ] [ 2.6.25.8 ] [ 2.6.31.13 ] Architecture: [ i386 ]
  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 
 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 
 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 
109 static void tpm_atml_cancel(struct tpm_chip *chip)
110 {
111         iowrite8(ATML_STATUS_ABORT, chip->vendor.iobase + 1);
112 }
113 
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 
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 int tpm_atml_suspend(struct platform_device *dev, pm_message_t msg)
172 {
173         return tpm_pm_suspend(&dev->dev, msg);
174 }
175 
176 static int tpm_atml_resume(struct platform_device *dev)
177 {
178         return tpm_pm_resume(&dev->dev);
179 }
180 static struct platform_driver atml_drv = {
181         .driver = {
182                 .name = "tpm_atmel",
183                 .owner          = THIS_MODULE,
184         },
185         .suspend = tpm_atml_suspend,
186         .resume = tpm_atml_resume,
187 };
188 
189 static int __init init_atmel(void)
190 {
191         int rc = 0;
192         void __iomem *iobase = NULL;
193         int have_region, region_size;
194         unsigned long base;
195         struct  tpm_chip *chip;
196 
197         rc = platform_driver_register(&atml_drv);
198         if (rc)
199                 return rc;
200 
201         if ((iobase = atmel_get_base_addr(&base, &region_size)) == NULL) {
202                 rc = -ENODEV;
203                 goto err_unreg_drv;
204         }
205 
206         have_region =
207             (atmel_request_region
208              (tpm_atmel.base, region_size, "tpm_atmel0") == NULL) ? 0 : 1;
209 
210         pdev = platform_device_register_simple("tpm_atmel", -1, NULL, 0);
211         if (IS_ERR(pdev)) {
212                 rc = PTR_ERR(pdev);
213                 goto err_rel_reg;
214         }
215 
216         if (!(chip = tpm_register_hardware(&pdev->dev, &tpm_atmel))) {
217                 rc = -ENODEV;
218                 goto err_unreg_dev;
219         }
220 
221         chip->vendor.iobase = iobase;
222         chip->vendor.base = base;
223         chip->vendor.have_region = have_region;
224         chip->vendor.region_size = region_size;
225 
226         return 0;
227 
228 err_unreg_dev:
229         platform_device_unregister(pdev);
230 err_rel_reg:
231         atmel_put_base_addr(iobase);
232         if (have_region)
233                 atmel_release_region(base,
234                                      region_size);
235 err_unreg_drv:
236         platform_driver_unregister(&atml_drv);
237         return rc;
238 }
239 
240 static void __exit cleanup_atmel(void)
241 {
242         platform_driver_unregister(&atml_drv);
243         atml_plat_remove();
244 }
245 
246 module_init(init_atmel);
247 module_exit(cleanup_atmel);
248 
249 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
250 MODULE_DESCRIPTION("TPM Driver");
251 MODULE_VERSION("2.0");
252 MODULE_LICENSE("GPL");
253 
  This page was automatically generated by the LXR engine.