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 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 }; 178 179 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 driver_register(&atml_drv); 188 189 if ((iobase = atmel_get_base_addr(&base, ®ion_size)) == NULL) { 190 rc = -ENODEV; 191 goto err_unreg_drv; 192 } 193 194 have_region = 195 (atmel_request_region 196 (tpm_atmel.base, region_size, "tpm_atmel0") == NULL) ? 0 : 1; 197 198 199 if (IS_ERR 200 (pdev = 201 platform_device_register_simple("tpm_atmel", -1, NULL, 0))) { 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 } 229 230 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