236 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2004 IBM Corporation4 *5 * Authors:6 * Leendert van Doorn <leendert@watson.ibm.com>7 * Dave Safford <safford@watson.ibm.com>8 * Reiner Sailer <sailer@watson.ibm.com>9 * Kylene Hall <kjhall@us.ibm.com>10 *11 * Maintained by: <tpmdd-devel@lists.sourceforge.net>12 *13 * Device driver for TCG/TCPA TPM (trusted platform module).14 * Specifications at www.trustedcomputinggroup.org 15 */16 17#include "tpm.h"18#include "tpm_atmel.h"19 20/* write status bits */21enum tpm_atmel_write_status {22 ATML_STATUS_ABORT = 0x01,23 ATML_STATUS_LASTBYTE = 0x0424};25/* read status bits */26enum tpm_atmel_read_status {27 ATML_STATUS_BUSY = 0x01,28 ATML_STATUS_DATA_AVAIL = 0x02,29 ATML_STATUS_REWRITE = 0x04,30 ATML_STATUS_READY = 0x0831};32 33static int tpm_atml_recv(struct tpm_chip *chip, u8 *buf, size_t count)34{35 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);36 u8 status, *hdr = buf;37 u32 size;38 int i;39 __be32 *native_size;40 41 /* start reading header */42 if (count < 6)43 return -EIO;44 45 for (i = 0; i < 6; i++) {46 status = ioread8(priv->iobase + 1);47 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {48 dev_err(&chip->dev, "error reading header\n");49 return -EIO;50 }51 *buf++ = ioread8(priv->iobase);52 }53 54 /* size of the data received */55 native_size = (__force __be32 *) (hdr + 2);56 size = be32_to_cpu(*native_size);57 58 if (count < size) {59 dev_err(&chip->dev,60 "Recv size(%d) less than available space\n", size);61 for (; i < size; i++) { /* clear the waiting data anyway */62 status = ioread8(priv->iobase + 1);63 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {64 dev_err(&chip->dev, "error reading data\n");65 return -EIO;66 }67 }68 return -EIO;69 }70 71 /* read all the data available */72 for (; i < size; i++) {73 status = ioread8(priv->iobase + 1);74 if ((status & ATML_STATUS_DATA_AVAIL) == 0) {75 dev_err(&chip->dev, "error reading data\n");76 return -EIO;77 }78 *buf++ = ioread8(priv->iobase);79 }80 81 /* make sure data available is gone */82 status = ioread8(priv->iobase + 1);83 84 if (status & ATML_STATUS_DATA_AVAIL) {85 dev_err(&chip->dev, "data available is stuck\n");86 return -EIO;87 }88 89 return size;90}91 92static int tpm_atml_send(struct tpm_chip *chip, u8 *buf, size_t count)93{94 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);95 int i;96 97 dev_dbg(&chip->dev, "tpm_atml_send:\n");98 for (i = 0; i < count; i++) {99 dev_dbg(&chip->dev, "%d 0x%x(%d)\n", i, buf[i], buf[i]);100 iowrite8(buf[i], priv->iobase);101 }102 103 return 0;104}105 106static void tpm_atml_cancel(struct tpm_chip *chip)107{108 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);109 110 iowrite8(ATML_STATUS_ABORT, priv->iobase + 1);111}112 113static u8 tpm_atml_status(struct tpm_chip *chip)114{115 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);116 117 return ioread8(priv->iobase + 1);118}119 120static bool tpm_atml_req_canceled(struct tpm_chip *chip, u8 status)121{122 return (status == ATML_STATUS_READY);123}124 125static const struct tpm_class_ops tpm_atmel = {126 .recv = tpm_atml_recv,127 .send = tpm_atml_send,128 .cancel = tpm_atml_cancel,129 .status = tpm_atml_status,130 .req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL,131 .req_complete_val = ATML_STATUS_DATA_AVAIL,132 .req_canceled = tpm_atml_req_canceled,133};134 135static struct platform_device *pdev;136 137static void atml_plat_remove(void)138{139 struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);140 struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);141 142 tpm_chip_unregister(chip);143 if (priv->have_region)144 atmel_release_region(priv->base, priv->region_size);145 atmel_put_base_addr(priv->iobase);146 platform_device_unregister(pdev);147}148 149static SIMPLE_DEV_PM_OPS(tpm_atml_pm, tpm_pm_suspend, tpm_pm_resume);150 151static struct platform_driver atml_drv = {152 .driver = {153 .name = "tpm_atmel",154 .pm = &tpm_atml_pm,155 },156};157 158static int __init init_atmel(void)159{160 int rc = 0;161 void __iomem *iobase = NULL;162 int have_region, region_size;163 unsigned long base;164 struct tpm_chip *chip;165 struct tpm_atmel_priv *priv;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_region178 (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 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);187 if (!priv) {188 rc = -ENOMEM;189 goto err_unreg_dev;190 }191 192 priv->iobase = iobase;193 priv->base = base;194 priv->have_region = have_region;195 priv->region_size = region_size;196 197 chip = tpmm_chip_alloc(&pdev->dev, &tpm_atmel);198 if (IS_ERR(chip)) {199 rc = PTR_ERR(chip);200 goto err_unreg_dev;201 }202 203 dev_set_drvdata(&chip->dev, priv);204 205 rc = tpm_chip_register(chip);206 if (rc)207 goto err_unreg_dev;208 209 return 0;210 211err_unreg_dev:212 platform_device_unregister(pdev);213err_rel_reg:214 atmel_put_base_addr(iobase);215 if (have_region)216 atmel_release_region(base,217 region_size);218err_unreg_drv:219 platform_driver_unregister(&atml_drv);220 return rc;221}222 223static void __exit cleanup_atmel(void)224{225 platform_driver_unregister(&atml_drv);226 atml_plat_remove();227}228 229module_init(init_atmel);230module_exit(cleanup_atmel);231 232MODULE_AUTHOR("Leendert van Doorn <leendert@watson.ibm.com>");233MODULE_DESCRIPTION("TPM Driver");234MODULE_VERSION("2.0");235MODULE_LICENSE("GPL");236