tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0
2/* Copyright (c) 2025 Loongson Technology Corporation Limited. */
3
4#include <linux/device.h>
5#include <linux/mfd/loongson-se.h>
6#include <linux/platform_device.h>
7#include <linux/wait.h>
8
9#include "tpm.h"
10
11struct tpm_loongson_cmd {
12 u32 cmd_id;
13 u32 data_off;
14 u32 data_len;
15 u32 pad[5];
16};
17
18static int tpm_loongson_recv(struct tpm_chip *chip, u8 *buf, size_t count)
19{
20 struct loongson_se_engine *tpm_engine = dev_get_drvdata(&chip->dev);
21 struct tpm_loongson_cmd *cmd_ret = tpm_engine->command_ret;
22
23 if (cmd_ret->data_len > count)
24 return -EIO;
25
26 memcpy(buf, tpm_engine->data_buffer, cmd_ret->data_len);
27
28 return cmd_ret->data_len;
29}
30
31static int tpm_loongson_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz, size_t count)
32{
33 struct loongson_se_engine *tpm_engine = dev_get_drvdata(&chip->dev);
34 struct tpm_loongson_cmd *cmd = tpm_engine->command;
35
36 if (count > tpm_engine->buffer_size)
37 return -E2BIG;
38
39 cmd->data_len = count;
40 memcpy(tpm_engine->data_buffer, buf, count);
41
42 return loongson_se_send_engine_cmd(tpm_engine);
43}
44
45static const struct tpm_class_ops tpm_loongson_ops = {
46 .flags = TPM_OPS_AUTO_STARTUP,
47 .recv = tpm_loongson_recv,
48 .send = tpm_loongson_send,
49};
50
51static int tpm_loongson_probe(struct platform_device *pdev)
52{
53 struct loongson_se_engine *tpm_engine;
54 struct device *dev = &pdev->dev;
55 struct tpm_loongson_cmd *cmd;
56 struct tpm_chip *chip;
57
58 tpm_engine = loongson_se_init_engine(dev->parent, SE_ENGINE_TPM);
59 if (!tpm_engine)
60 return -ENODEV;
61 cmd = tpm_engine->command;
62 cmd->cmd_id = SE_CMD_TPM;
63 cmd->data_off = tpm_engine->buffer_off;
64
65 chip = tpmm_chip_alloc(dev, &tpm_loongson_ops);
66 if (IS_ERR(chip))
67 return PTR_ERR(chip);
68 chip->flags = TPM_CHIP_FLAG_TPM2 | TPM_CHIP_FLAG_IRQ;
69 dev_set_drvdata(&chip->dev, tpm_engine);
70
71 return tpm_chip_register(chip);
72}
73
74static struct platform_driver tpm_loongson = {
75 .probe = tpm_loongson_probe,
76 .driver = {
77 .name = "tpm_loongson",
78 },
79};
80module_platform_driver(tpm_loongson);
81
82MODULE_ALIAS("platform:tpm_loongson");
83MODULE_LICENSE("GPL");
84MODULE_DESCRIPTION("Loongson TPM driver");