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Diffstat (limited to 'drivers/char/tpm/tpm_atmel.c')
-rw-r--r--drivers/char/tpm/tpm_atmel.c235
1 files changed, 235 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm_atmel.c b/drivers/char/tpm/tpm_atmel.c
new file mode 100644
index 000000000..54a6750a6
--- /dev/null
+++ b/drivers/char/tpm/tpm_atmel.c
@@ -0,0 +1,235 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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
+ */
+
+#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)
+{
+ struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
+ 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(priv->iobase + 1);
+ if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
+ dev_err(&chip->dev, "error reading header\n");
+ return -EIO;
+ }
+ *buf++ = ioread8(priv->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(priv->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(priv->iobase + 1);
+ if ((status & ATML_STATUS_DATA_AVAIL) == 0) {
+ dev_err(&chip->dev, "error reading data\n");
+ return -EIO;
+ }
+ *buf++ = ioread8(priv->iobase);
+ }
+
+ /* make sure data available is gone */
+ status = ioread8(priv->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)
+{
+ struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
+ 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], priv->iobase);
+ }
+
+ return 0;
+}
+
+static void tpm_atml_cancel(struct tpm_chip *chip)
+{
+ struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
+
+ iowrite8(ATML_STATUS_ABORT, priv->iobase + 1);
+}
+
+static u8 tpm_atml_status(struct tpm_chip *chip)
+{
+ struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
+
+ return ioread8(priv->iobase + 1);
+}
+
+static bool tpm_atml_req_canceled(struct tpm_chip *chip, u8 status)
+{
+ return (status == ATML_STATUS_READY);
+}
+
+static const struct tpm_class_ops 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 = tpm_atml_req_canceled,
+};
+
+static struct platform_device *pdev;
+
+static void atml_plat_remove(void)
+{
+ struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
+ struct tpm_atmel_priv *priv = dev_get_drvdata(&chip->dev);
+
+ tpm_chip_unregister(chip);
+ if (priv->have_region)
+ atmel_release_region(priv->base, priv->region_size);
+ atmel_put_base_addr(priv->iobase);
+ platform_device_unregister(pdev);
+}
+
+static SIMPLE_DEV_PM_OPS(tpm_atml_pm, tpm_pm_suspend, tpm_pm_resume);
+
+static struct platform_driver atml_drv = {
+ .driver = {
+ .name = "tpm_atmel",
+ .pm = &tpm_atml_pm,
+ },
+};
+
+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;
+ struct tpm_atmel_priv *priv;
+
+ rc = platform_driver_register(&atml_drv);
+ if (rc)
+ return rc;
+
+ if ((iobase = atmel_get_base_addr(&base, &region_size)) == NULL) {
+ rc = -ENODEV;
+ goto err_unreg_drv;
+ }
+
+ have_region =
+ (atmel_request_region
+ (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;
+ }
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ rc = -ENOMEM;
+ goto err_unreg_dev;
+ }
+
+ priv->iobase = iobase;
+ priv->base = base;
+ priv->have_region = have_region;
+ priv->region_size = region_size;
+
+ chip = tpmm_chip_alloc(&pdev->dev, &tpm_atmel);
+ if (IS_ERR(chip)) {
+ rc = PTR_ERR(chip);
+ goto err_unreg_dev;
+ }
+
+ dev_set_drvdata(&chip->dev, priv);
+
+ rc = tpm_chip_register(chip);
+ if (rc)
+ goto err_unreg_dev;
+
+ 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");