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 bool tpm_atml_req_canceled(struct tpm_chip *chip, u8 status) 120 { 121 return (status == ATML_STATUS_READY); 122 } 123 124 static const struct file_operations atmel_ops = { 125 .owner = THIS_MODULE, 126 .llseek = no_llseek, 127 .open = tpm_open, 128 .read = tpm_read, 129 .write = tpm_write, 130 .release = tpm_release, 131 }; 132 133 static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL); 134 static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL); 135 static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL); 136 static DEVICE_ATTR(cancel, S_IWUSR |S_IWGRP, NULL, tpm_store_cancel); 137 138 static struct attribute* atmel_attrs[] = { 139 &dev_attr_pubek.attr, 140 &dev_attr_pcrs.attr, 141 &dev_attr_caps.attr, 142 &dev_attr_cancel.attr, 143 NULL, 144 }; 145 146 static struct attribute_group atmel_attr_grp = { .attrs = atmel_attrs }; 147 148 static const struct tpm_vendor_specific tpm_atmel = { 149 .recv = tpm_atml_recv, 150 .send = tpm_atml_send, 151 .cancel = tpm_atml_cancel, 152 .status = tpm_atml_status, 153 .req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL, 154 .req_complete_val = ATML_STATUS_DATA_AVAIL, 155 .req_canceled = tpm_atml_req_canceled, 156 .attr_group = &atmel_attr_grp, 157 .miscdev = { .fops = &atmel_ops, }, 158 }; 159 160 static struct platform_device *pdev; 161 162 static void atml_plat_remove(void) 163 { 164 struct tpm_chip *chip = dev_get_drvdata(&pdev->dev); 165 166 if (chip) { 167 if (chip->vendor.have_region) 168 atmel_release_region(chip->vendor.base, 169 chip->vendor.region_size); 170 atmel_put_base_addr(chip->vendor.iobase); 171 tpm_remove_hardware(chip->dev); 172 platform_device_unregister(pdev); 173 } 174 } 175 176 static SIMPLE_DEV_PM_OPS(tpm_atml_pm, tpm_pm_suspend, tpm_pm_resume); 177 178 static struct platform_driver atml_drv = { 179 .driver = { 180 .name = "tpm_atmel", 181 .owner = THIS_MODULE, 182 .pm = &tpm_atml_pm, 183 }, 184 }; 185 186 static int __init init_atmel(void) 187 { 188 int rc = 0; 189 void __iomem *iobase = NULL; 190 int have_region, region_size; 191 unsigned long base; 192 struct tpm_chip *chip; 193 194 rc = platform_driver_register(&atml_drv); 195 if (rc) 196 return rc; 197 198 if ((iobase = atmel_get_base_addr(&base, ®ion_size)) == NULL) { 199 rc = -ENODEV; 200 goto err_unreg_drv; 201 } 202 203 have_region = 204 (atmel_request_region 205 (base, region_size, "tpm_atmel0") == NULL) ? 0 : 1; 206 207 pdev = platform_device_register_simple("tpm_atmel", -1, NULL, 0); 208 if (IS_ERR(pdev)) { 209 rc = PTR_ERR(pdev); 210 goto err_rel_reg; 211 } 212 213 if (!(chip = tpm_register_hardware(&pdev->dev, &tpm_atmel))) { 214 rc = -ENODEV; 215 goto err_unreg_dev; 216 } 217 218 chip->vendor.iobase = iobase; 219 chip->vendor.base = base; 220 chip->vendor.have_region = have_region; 221 chip->vendor.region_size = region_size; 222 223 return 0; 224 225 err_unreg_dev: 226 platform_device_unregister(pdev); 227 err_rel_reg: 228 atmel_put_base_addr(iobase); 229 if (have_region) 230 atmel_release_region(base, 231 region_size); 232 err_unreg_drv: 233 platform_driver_unregister(&atml_drv); 234 return rc; 235 } 236 237 static void __exit cleanup_atmel(void) 238 { 239 platform_driver_unregister(&atml_drv); 240 atml_plat_remove(); 241 } 242 243 module_init(init_atmel); 244 module_exit(cleanup_atmel); 245 246 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); 247 MODULE_DESCRIPTION("TPM Driver"); 248 MODULE_VERSION("2.0"); 249 MODULE_LICENSE("GPL"); 250