aboutsummaryrefslogtreecommitdiff
path: root/drivers/tpm/tpm-uclass.c
blob: b6e1fc5e6280bafaefe9f98d0539d72fca46871d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/*
 * Copyright (c) 2015 Google, Inc
 * Written by Simon Glass <sjg@chromium.org>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <dm.h>
#include <tpm.h>
#include <linux/unaligned/be_byteshift.h>
#include "tpm_internal.h"

int tpm_open(struct udevice *dev)
{
	struct tpm_ops *ops = tpm_get_ops(dev);

	if (!ops->open)
		return -ENOSYS;

	return ops->open(dev);
}

int tpm_close(struct udevice *dev)
{
	struct tpm_ops *ops = tpm_get_ops(dev);

	if (!ops->close)
		return -ENOSYS;

	return ops->close(dev);
}

int tpm_get_desc(struct udevice *dev, char *buf, int size)
{
	struct tpm_ops *ops = tpm_get_ops(dev);

	if (!ops->get_desc)
		return -ENOSYS;

	return ops->get_desc(dev, buf, size);
}

/* Returns max number of milliseconds to wait */
static ulong tpm_tis_i2c_calc_ordinal_duration(struct tpm_chip_priv *priv,
					       u32 ordinal)
{
	int duration_idx = TPM_UNDEFINED;
	int duration = 0;

	if (ordinal < TPM_MAX_ORDINAL) {
		duration_idx = tpm_ordinal_duration[ordinal];
	} else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
			TPM_MAX_PROTECTED_ORDINAL) {
		duration_idx = tpm_protected_ordinal_duration[
				ordinal & TPM_PROTECTED_ORDINAL_MASK];
	}

	if (duration_idx != TPM_UNDEFINED)
		duration = priv->duration_ms[duration_idx];

	if (duration <= 0)
		return 2 * 60 * 1000; /* Two minutes timeout */
	else
		return duration;
}

int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size,
	uint8_t *recvbuf, size_t *recv_size)
{
	struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
	struct tpm_ops *ops = tpm_get_ops(dev);
	ulong start, stop;
	uint count, ordinal;
	int ret, ret2;

	if (ops->xfer)
		return ops->xfer(dev, sendbuf, send_size, recvbuf, recv_size);

	if (!ops->send || !ops->recv)
		return -ENOSYS;

	/* switch endianess: big->little */
	count = get_unaligned_be32(sendbuf + TPM_CMD_COUNT_BYTE);
	ordinal = get_unaligned_be32(sendbuf + TPM_CMD_ORDINAL_BYTE);

	if (count == 0) {
		debug("no data\n");
		return -ENODATA;
	}
	if (count > send_size) {
		debug("invalid count value %x %zx\n", count, send_size);
		return -E2BIG;
	}

	debug("%s: Calling send\n", __func__);
	ret = ops->send(dev, sendbuf, send_size);
	if (ret < 0)
		return ret;

	start = get_timer(0);
	stop = tpm_tis_i2c_calc_ordinal_duration(priv, ordinal);
	do {
		ret = ops->recv(dev, priv->buf, sizeof(priv->buf));
		if (ret >= 0) {
			if (ret > *recv_size)
				return -ENOSPC;
			memcpy(recvbuf, priv->buf, ret);
			*recv_size = ret;
			ret = 0;
			break;
		} else if (ret != -EAGAIN) {
			return ret;
		}

		mdelay(priv->retry_time_ms);
		if (get_timer(start) > stop) {
			ret = -ETIMEDOUT;
			break;
		}
	} while (ret);

	ret2 = ops->cleanup ? ops->cleanup(dev) : 0;

	return ret2 ? ret2 : ret;
}

UCLASS_DRIVER(tpm) = {
	.id             = UCLASS_TPM,
	.name           = "tpm",
	.flags          = DM_UC_FLAG_SEQ_ALIAS,
	.per_device_auto_alloc_size	= sizeof(struct tpm_chip_priv),
};