tpm_atmel.c
/*
* Copyright (C) 2004 IBM Corporation
*
* Authors:
* Leendert van Doorn <leendert@watson.ibm.com>
* Dave Safford <safford@watson.ibm.com>
* Reiner Sailer <sailer@watson.ibm.com>
* Kylene Hall <kjhall@us.ibm.com>
*
* Maintained by: <tpmdd-devel@lists.sourceforge.net>
*
* Device driver for TCG/TCPA TPM (trusted platform module).
* Specifications at www.trustedcomputinggroup.org
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2 of the
* License.
*
*/
#include "tpm.h"
#include "tpm_atmel.h"
/* write status bits */
enum tpm_atmel_write_status {
ATML_STATUS_ABORT = 0x01,
ATML_STATUS_LASTBYTE = 0x04
};
/* read status bits */
enum tpm_atmel_read_status {
ATML_STATUS_BUSY = 0x01,
ATML_STATUS_DATA_AVAIL = 0x02,
ATML_STATUS_REWRITE = 0x04,
ATML_STATUS_READY = 0x08
};
static int tpm_atml_recv(struct tpm_chip *chip, u8 *buf, size_t count)
{
u8 status, *hdr = buf;
u32 size;
int i;
__be32 *native_size;
/* start reading header */
if (count < 6)
return -EIO;
for (i = 0; i < 6; i++) {
status = ioread8(chip->vendor.iobase + 1);
if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
dev_err(chip->dev, "error reading header\n");
return -EIO;
}
*buf++ = ioread8(chip->vendor.iobase);
}
/* size of the data received */
native_size = (__force __be32 *) (hdr + 2);
size = be32_to_cpu(*native_size);
if (count < size) {
dev_err(chip->dev,
"Recv size(%d) less than available space\n", size);
for (; i < size; i++) { /* clear the waiting data anyway */
status = ioread8(chip->vendor.iobase + 1);
if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
dev_err(chip->dev, "error reading data\n");
return -EIO;
}
}
return -EIO;
}
/* read all the data available */
for (; i < size; i++) {
status = ioread8(chip->vendor.iobase + 1);
if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
dev_err(chip->dev, "error reading data\n");
return -EIO;
}
*buf++ = ioread8(chip->vendor.iobase);
}
/* make sure data available is gone */
status = ioread8(chip->vendor.iobase + 1);
if (status & ATML_STATUS_DATA_AVAIL) {
dev_err(chip->dev, "data available is stuck\n");
return -EIO;
}
return size;
}
static int tpm_atml_send(struct tpm_chip *chip, u8 *buf, size_t count)
{
int i;
dev_dbg(chip->dev, "tpm_atml_send:\n");
for (i = 0; i < count; i++) {
dev_dbg(chip->dev, "%d 0x%x(%d)\n", i, buf[i], buf[i]);
iowrite8(buf[i], chip->vendor.iobase);
}
return count;
}
static void tpm_atml_cancel(struct tpm_chip *chip)
{
iowrite8(ATML_STATUS_ABORT, chip->vendor.iobase + 1);
}
static u8 tpm_atml_status(struct tpm_chip *chip)
{
return ioread8(chip->vendor.iobase + 1);
}
static const struct file_operations atmel_ops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.open = tpm_open,
.read = tpm_read,
.write = tpm_write,
.release = tpm_release,
};
static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
static DEVICE_ATTR(cancel, S_IWUSR |S_IWGRP, NULL, tpm_store_cancel);
static struct attribute* atmel_attrs[] = {
&dev_attr_pubek.attr,
&dev_attr_pcrs.attr,
&dev_attr_caps.attr,
&dev_attr_cancel.attr,
NULL,
};
static struct attribute_group atmel_attr_grp = { .attrs = atmel_attrs };
static const struct tpm_vendor_specific tpm_atmel = {
.recv = tpm_atml_recv,
.send = tpm_atml_send,
.cancel = tpm_atml_cancel,
.status = tpm_atml_status,
.req_complete_mask = ATML_STATUS_BUSY | ATML_STATUS_DATA_AVAIL,
.req_complete_val = ATML_STATUS_DATA_AVAIL,
.req_canceled = ATML_STATUS_READY,
.attr_group = &atmel_attr_grp,
.miscdev = { .fops = &atmel_ops, },
};
static struct platform_device *pdev;
static void atml_plat_remove(void)
{
struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
if (chip) {
if (chip->vendor.have_region)
atmel_release_region(chip->vendor.base,
chip->vendor.region_size);
atmel_put_base_addr(chip->vendor.iobase);
tpm_remove_hardware(chip->dev);
platform_device_unregister(pdev);
}
}
static int tpm_atml_suspend(struct platform_device *dev, pm_message_t msg)
{
return tpm_pm_suspend(&dev->dev, msg);
}
static int tpm_atml_resume(struct platform_device *dev)
{
return tpm_pm_resume(&dev->dev);
}
static struct platform_driver atml_drv = {
.driver = {
.name = "tpm_atmel",
.owner = THIS_MODULE,
},
.suspend = tpm_atml_suspend,
.resume = tpm_atml_resume,
};
static int __init init_atmel(void)
{
int rc = 0;
void __iomem *iobase = NULL;
int have_region, region_size;
unsigned long base;
struct tpm_chip *chip;
rc = platform_driver_register(&atml_drv);
if (rc)
return rc;
if ((iobase = atmel_get_base_addr(&base, ®ion_size)) == NULL) {
rc = -ENODEV;
goto err_unreg_drv;
}
have_region =
(atmel_request_region
(tpm_atmel.base, region_size, "tpm_atmel0") == NULL) ? 0 : 1;
pdev = platform_device_register_simple("tpm_atmel", -1, NULL, 0);
if (IS_ERR(pdev)) {
rc = PTR_ERR(pdev);
goto err_rel_reg;
}
if (!(chip = tpm_register_hardware(&pdev->dev, &tpm_atmel))) {
rc = -ENODEV;
goto err_unreg_dev;
}
chip->vendor.iobase = iobase;
chip->vendor.base = base;
chip->vendor.have_region = have_region;
chip->vendor.region_size = region_size;
return 0;
err_unreg_dev:
platform_device_unregister(pdev);
err_rel_reg:
atmel_put_base_addr(iobase);
if (have_region)
atmel_release_region(base,
region_size);
err_unreg_drv:
platform_driver_unregister(&atml_drv);
return rc;
}
static void __exit cleanup_atmel(void)
{
platform_driver_unregister(&atml_drv);
atml_plat_remove();
}
module_init(init_atmel);
module_exit(cleanup_atmel);
MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
MODULE_DESCRIPTION("TPM Driver");
MODULE_VERSION("2.0");
MODULE_LICENSE("GPL");