1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2020 Linaro Ltd.
4 *
5 * This device driver implements MMIO TPM on SynQuacer Platform.
6 */
7#include <linux/acpi.h>
8#include <linux/init.h>
9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/of.h>
12#include <linux/kernel.h>
13#include "tpm.h"
14#include "tpm_tis_core.h"
15
16/*
17 * irq > 0 means: use irq $irq;
18 * irq = 0 means: autoprobe for an irq;
19 * irq = -1 means: no irq support
20 */
21struct tpm_tis_synquacer_info {
22 struct resource res;
23 int irq;
24};
25
26struct tpm_tis_synquacer_phy {
27 struct tpm_tis_data priv;
28 void __iomem *iobase;
29};
30
31static inline struct tpm_tis_synquacer_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data)
32{
33 return container_of(data, struct tpm_tis_synquacer_phy, priv);
34}
35
36static int tpm_tis_synquacer_read_bytes(struct tpm_tis_data *data, u32 addr,
37 u16 len, u8 *result,
38 enum tpm_tis_io_mode io_mode)
39{
40 struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
41 switch (io_mode) {
42 case TPM_TIS_PHYS_8:
43 while (len--)
44 *result++ = ioread8(phy->iobase + addr);
45 break;
46 case TPM_TIS_PHYS_16:
47 result[1] = ioread8(phy->iobase + addr + 1);
48 result[0] = ioread8(phy->iobase + addr);
49 break;
50 case TPM_TIS_PHYS_32:
51 result[3] = ioread8(phy->iobase + addr + 3);
52 result[2] = ioread8(phy->iobase + addr + 2);
53 result[1] = ioread8(phy->iobase + addr + 1);
54 result[0] = ioread8(phy->iobase + addr);
55 break;
56 }
57
58 return 0;
59}
60
61static int tpm_tis_synquacer_write_bytes(struct tpm_tis_data *data, u32 addr,
62 u16 len, const u8 *value,
63 enum tpm_tis_io_mode io_mode)
64{
65 struct tpm_tis_synquacer_phy *phy = to_tpm_tis_tcg_phy(data);
66 switch (io_mode) {
67 case TPM_TIS_PHYS_8:
68 while (len--)
69 iowrite8(*value++, phy->iobase + addr);
70 break;
71 case TPM_TIS_PHYS_16:
72 return -EINVAL;
73 case TPM_TIS_PHYS_32:
74 /*
75 * Due to the limitation of SPI controller on SynQuacer,
76 * 16/32 bits access must be done in byte-wise and descending order.
77 */
78 iowrite8(value[3], phy->iobase + addr + 3);
79 iowrite8(value[2], phy->iobase + addr + 2);
80 iowrite8(value[1], phy->iobase + addr + 1);
81 iowrite8(value[0], phy->iobase + addr);
82 break;
83 }
84
85 return 0;
86}
87
88static const struct tpm_tis_phy_ops tpm_tcg_bw = {
89 .read_bytes = tpm_tis_synquacer_read_bytes,
90 .write_bytes = tpm_tis_synquacer_write_bytes,
91};
92
93static int tpm_tis_synquacer_init(struct device *dev,
94 struct tpm_tis_synquacer_info *tpm_info)
95{
96 struct tpm_tis_synquacer_phy *phy;
97
98 phy = devm_kzalloc(dev, size: sizeof(struct tpm_tis_synquacer_phy), GFP_KERNEL);
99 if (phy == NULL)
100 return -ENOMEM;
101
102 phy->iobase = devm_ioremap_resource(dev, res: &tpm_info->res);
103 if (IS_ERR(ptr: phy->iobase))
104 return PTR_ERR(ptr: phy->iobase);
105
106 return tpm_tis_core_init(dev, priv: &phy->priv, irq: tpm_info->irq, phy_ops: &tpm_tcg_bw,
107 ACPI_HANDLE(dev));
108}
109
110static SIMPLE_DEV_PM_OPS(tpm_tis_synquacer_pm, tpm_pm_suspend, tpm_tis_resume);
111
112static int tpm_tis_synquacer_probe(struct platform_device *pdev)
113{
114 struct tpm_tis_synquacer_info tpm_info = {};
115 struct resource *res;
116
117 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
118 if (res == NULL) {
119 dev_err(&pdev->dev, "no memory resource defined\n");
120 return -ENODEV;
121 }
122 tpm_info.res = *res;
123
124 tpm_info.irq = -1;
125
126 return tpm_tis_synquacer_init(dev: &pdev->dev, tpm_info: &tpm_info);
127}
128
129static void tpm_tis_synquacer_remove(struct platform_device *pdev)
130{
131 struct tpm_chip *chip = dev_get_drvdata(dev: &pdev->dev);
132
133 tpm_chip_unregister(chip);
134 tpm_tis_remove(chip);
135}
136
137#ifdef CONFIG_OF
138static const struct of_device_id tis_synquacer_of_platform_match[] = {
139 {.compatible = "socionext,synquacer-tpm-mmio"},
140 {},
141};
142MODULE_DEVICE_TABLE(of, tis_synquacer_of_platform_match);
143#endif
144
145#ifdef CONFIG_ACPI
146static const struct acpi_device_id tpm_synquacer_acpi_tbl[] = {
147 { "SCX0009" },
148 {},
149};
150MODULE_DEVICE_TABLE(acpi, tpm_synquacer_acpi_tbl);
151#endif
152
153static struct platform_driver tis_synquacer_drv = {
154 .probe = tpm_tis_synquacer_probe,
155 .remove_new = tpm_tis_synquacer_remove,
156 .driver = {
157 .name = "tpm_tis_synquacer",
158 .pm = &tpm_tis_synquacer_pm,
159 .of_match_table = of_match_ptr(tis_synquacer_of_platform_match),
160 .acpi_match_table = ACPI_PTR(tpm_synquacer_acpi_tbl),
161 },
162};
163
164module_platform_driver(tis_synquacer_drv);
165
166MODULE_DESCRIPTION("TPM MMIO Driver for Socionext SynQuacer platform");
167MODULE_LICENSE("GPL");
168

source code of linux/drivers/char/tpm/tpm_tis_synquacer.c