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->pdev, "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->pdev, 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->pdev, "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->pdev, "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->pdev, "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->pdev, "tpm_atml_send:\n"); 101 for (i = 0; i < count; i++) { 102 dev_dbg(chip->pdev, "%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 tpm_class_ops tpm_atmel = { 125 .recv = tpm_atml_recv, 126 .send = tpm_atml_send, 127 .cancel = tpm_atml_cancel, 128 .status = tpm_atml_status, 129 .req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL, 130 .req_complete_val = ATML_STATUS_DATA_AVAIL, 131 .req_canceled = tpm_atml_req_canceled, 132 }; 133 134 static struct platform_device *pdev; 135 136 static void atml_plat_remove(void) 137 { 138 struct tpm_chip *chip = dev_get_drvdata(&pdev->dev); 139 140 if (chip) { 141 tpm_chip_unregister(chip); 142 if (chip->vendor.have_region) 143 atmel_release_region(chip->vendor.base, 144 chip->vendor.region_size); 145 atmel_put_base_addr(chip->vendor.iobase); 146 platform_device_unregister(pdev); 147 } 148 } 149 150 static SIMPLE_DEV_PM_OPS(tpm_atml_pm, tpm_pm_suspend, tpm_pm_resume); 151 152 static struct platform_driver atml_drv = { 153 .driver = { 154 .name = "tpm_atmel", 155 .pm = &tpm_atml_pm, 156 }, 157 }; 158 159 static int __init init_atmel(void) 160 { 161 int rc = 0; 162 void __iomem *iobase = NULL; 163 int have_region, region_size; 164 unsigned long base; 165 struct tpm_chip *chip; 166 167 rc = platform_driver_register(&atml_drv); 168 if (rc) 169 return rc; 170 171 if ((iobase = atmel_get_base_addr(&base, ®ion_size)) == NULL) { 172 rc = -ENODEV; 173 goto err_unreg_drv; 174 } 175 176 have_region = 177 (atmel_request_region 178 (base, region_size, "tpm_atmel0") == NULL) ? 0 : 1; 179 180 pdev = platform_device_register_simple("tpm_atmel", -1, NULL, 0); 181 if (IS_ERR(pdev)) { 182 rc = PTR_ERR(pdev); 183 goto err_rel_reg; 184 } 185 186 chip = tpmm_chip_alloc(&pdev->dev, &tpm_atmel); 187 if (IS_ERR(chip)) { 188 rc = PTR_ERR(chip); 189 goto err_unreg_dev; 190 } 191 192 chip->vendor.iobase = iobase; 193 chip->vendor.base = base; 194 chip->vendor.have_region = have_region; 195 chip->vendor.region_size = region_size; 196 197 rc = tpm_chip_register(chip); 198 if (rc) 199 goto err_unreg_dev; 200 201 return 0; 202 203 err_unreg_dev: 204 platform_device_unregister(pdev); 205 err_rel_reg: 206 atmel_put_base_addr(iobase); 207 if (have_region) 208 atmel_release_region(base, 209 region_size); 210 err_unreg_drv: 211 platform_driver_unregister(&atml_drv); 212 return rc; 213 } 214 215 static void __exit cleanup_atmel(void) 216 { 217 platform_driver_unregister(&atml_drv); 218 atml_plat_remove(); 219 } 220 221 module_init(init_atmel); 222 module_exit(cleanup_atmel); 223 224 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); 225 MODULE_DESCRIPTION("TPM Driver"); 226 MODULE_VERSION("2.0"); 227 MODULE_LICENSE("GPL"); 228