]> Git Repo - u-boot.git/blame - drivers/tpm/tpm_atmel_twi.c
Restore patch series "arm: dts: am62-beagleplay: Fix Beagleplay Ethernet"
[u-boot.git] / drivers / tpm / tpm_atmel_twi.c
CommitLineData
83d290c5 1// SPDX-License-Identifier: GPL-2.0+
c01939c7 2/*
07470d6f 3 * Copyright (C) 2013 Guntermann & Drunck, GmbH
c01939c7 4 *
d38826a3 5 * Written by Dirk Eibach <[email protected]>
c01939c7
DE
6 */
7
4e4bf944 8#include <display_options.h>
302c5dba 9#include <dm.h>
d677bfe2 10#include <tpm-v1.h>
c01939c7 11#include <i2c.h>
03de305e 12#include <time.h>
c01939c7 13#include <asm/unaligned.h>
c05ed00a 14#include <linux/delay.h>
c01939c7 15
302c5dba
CR
16#include "tpm_internal.h"
17
c01939c7
DE
18#define ATMEL_TPM_TIMEOUT_MS 5000 /* sufficient for anything but
19 generating/exporting keys */
20
21/*
302c5dba 22 * tpm_atmel_twi_open()
c01939c7
DE
23 *
24 * Requests access to locality 0 for the caller. After all commands have been
25 * completed the caller is supposed to call tis_close().
26 *
27 * Returns 0 on success, -1 on failure.
28 */
302c5dba 29static int tpm_atmel_twi_open(struct udevice *dev)
c01939c7
DE
30{
31 return 0;
32}
33
34/*
302c5dba 35 * tpm_atmel_twi_close()
c01939c7
DE
36 *
37 * terminate the currect session with the TPM by releasing the locked
38 * locality. Returns 0 on success of -1 on failure (in case lock
39 * removal did not succeed).
40 */
302c5dba
CR
41static int tpm_atmel_twi_close(struct udevice *dev)
42{
43 return 0;
44}
45
46/*
47 * tpm_atmel_twi_get_desc()
48 *
49 * @dev: Device to check
50 * @buf: Buffer to put the string
51 * @size: Maximum size of buffer
185f812c 52 * Return: length of string, or -ENOSPC it no space
302c5dba
CR
53 */
54static int tpm_atmel_twi_get_desc(struct udevice *dev, char *buf, int size)
c01939c7 55{
fb30d99d
MM
56 if (size < 50)
57 return -ENOSPC;
58
59 return snprintf(buf, size, "Atmel AT97SC3204T I2C 1.2 TPM (%s)", dev->name);
c01939c7
DE
60}
61
62/*
302c5dba 63 * tpm_atmel_twi_xfer()
c01939c7
DE
64 *
65 * Send the requested data to the TPM and then try to get its response
66 *
67 * @sendbuf - buffer of the data to send
68 * @send_size size of the data to send
69 * @recvbuf - memory to save the response to
70 * @recv_len - pointer to the size of the response buffer
71 *
72 * Returns 0 on success (and places the number of response bytes at recv_len)
73 * or -1 on failure.
74 */
302c5dba
CR
75static int tpm_atmel_twi_xfer(struct udevice *dev,
76 const uint8_t *sendbuf, size_t send_size,
77 uint8_t *recvbuf, size_t *recv_len)
c01939c7
DE
78{
79 int res;
80 unsigned long start;
81
82#ifdef DEBUG
83 memset(recvbuf, 0xcc, *recv_len);
84 printf("send to TPM (%d bytes, recv_len=%d):\n", send_size, *recv_len);
85 print_buffer(0, (void *)sendbuf, 1, send_size, 0);
86#endif
87
03dcd410 88 res = dm_i2c_write(dev, 0, sendbuf, send_size);
c01939c7
DE
89 if (res) {
90 printf("i2c_write returned %d\n", res);
91 return -1;
92 }
93
94 start = get_timer(0);
02f50d8e 95
03dcd410 96 while ((res = dm_i2c_read(dev, 0, recvbuf, 10)))
03dcd410 97 {
302c5dba 98 /* TODO Use TIS_TIMEOUT from tpm_tis_infineon.h */
c01939c7
DE
99 if (get_timer(start) > ATMEL_TPM_TIMEOUT_MS) {
100 puts("tpm timed out\n");
101 return -1;
102 }
103 udelay(100);
104 }
105 if (!res) {
b3f40703
JB
106 unsigned int hdr_recv_len;
107 hdr_recv_len = get_unaligned_be32(recvbuf + 2);
108 if (hdr_recv_len < 10) {
109 puts("tpm response header too small\n");
110 return -1;
111 } else if (hdr_recv_len > *recv_len) {
112 puts("tpm response length is bigger than receive buffer\n");
113 return -1;
114 } else {
115 *recv_len = hdr_recv_len;
03dcd410 116 res = dm_i2c_read(dev, 0, recvbuf, *recv_len);
b3f40703 117 }
c01939c7
DE
118 }
119 if (res) {
4a08dba0 120 printf("i2c_read returned %d (rlen=%zu)\n", res, *recv_len);
c01939c7
DE
121#ifdef DEBUG
122 print_buffer(0, recvbuf, 1, *recv_len, 0);
123#endif
124 }
125
126#ifdef DEBUG
127 if (!res) {
128 printf("read from TPM (%d bytes):\n", *recv_len);
129 print_buffer(0, recvbuf, 1, *recv_len, 0);
130 }
131#endif
132
133 return res;
134}
302c5dba
CR
135
136static int tpm_atmel_twi_probe(struct udevice *dev)
137{
fdb4a5fc 138 i2c_set_chip_offset_len(dev, 0);
302c5dba
CR
139 return 0;
140}
141
142static const struct udevice_id tpm_atmel_twi_ids[] = {
143 { .compatible = "atmel,at97sc3204t"},
144 { }
145};
146
147static const struct tpm_ops tpm_atmel_twi_ops = {
148 .open = tpm_atmel_twi_open,
149 .close = tpm_atmel_twi_close,
150 .xfer = tpm_atmel_twi_xfer,
151 .get_desc = tpm_atmel_twi_get_desc,
152};
153
154U_BOOT_DRIVER(tpm_atmel_twi) = {
155 .name = "tpm_atmel_twi",
156 .id = UCLASS_TPM,
157 .of_match = tpm_atmel_twi_ids,
158 .ops = &tpm_atmel_twi_ops,
159 .probe = tpm_atmel_twi_probe,
160};
This page took 0.29143 seconds and 4 git commands to generate.