1// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2/* Copyright(c) 2021-2023 Realtek Corporation
3 */
4
5#include <linux/acpi.h>
6#include <linux/uuid.h>
7
8#include "acpi.h"
9#include "debug.h"
10
11static const guid_t rtw89_guid = GUID_INIT(0xD2A8C3E8, 0x4B69, 0x4F00,
12 0x82, 0xBD, 0xFE, 0x86,
13 0x07, 0x80, 0x3A, 0xA7);
14
15static
16int rtw89_acpi_dsm_get_value(struct rtw89_dev *rtwdev, union acpi_object *obj,
17 u8 *value)
18{
19 if (obj->type != ACPI_TYPE_INTEGER) {
20 rtw89_debug(rtwdev, mask: RTW89_DBG_ACPI,
21 fmt: "acpi: expect integer but type: %d\n", obj->type);
22 return -EINVAL;
23 }
24
25 *value = (u8)obj->integer.value;
26 return 0;
27}
28
29static bool chk_acpi_policy_6ghz_sig(const struct rtw89_acpi_policy_6ghz *p)
30{
31 return p->signature[0] == 0x00 &&
32 p->signature[1] == 0xE0 &&
33 p->signature[2] == 0x4C;
34}
35
36static
37int rtw89_acpi_dsm_get_policy_6ghz(struct rtw89_dev *rtwdev,
38 union acpi_object *obj,
39 struct rtw89_acpi_policy_6ghz **policy_6ghz)
40{
41 const struct rtw89_acpi_policy_6ghz *ptr;
42 u32 expect_len;
43 u32 len;
44
45 if (obj->type != ACPI_TYPE_BUFFER) {
46 rtw89_debug(rtwdev, mask: RTW89_DBG_ACPI,
47 fmt: "acpi: expect buffer but type: %d\n", obj->type);
48 return -EINVAL;
49 }
50
51 len = obj->buffer.length;
52 if (len < sizeof(*ptr)) {
53 rtw89_debug(rtwdev, mask: RTW89_DBG_ACPI, fmt: "%s: invalid buffer length: %u\n",
54 __func__, len);
55 return -EINVAL;
56 }
57
58 ptr = (typeof(ptr))obj->buffer.pointer;
59 if (!chk_acpi_policy_6ghz_sig(p: ptr)) {
60 rtw89_debug(rtwdev, mask: RTW89_DBG_ACPI, fmt: "%s: bad signature\n", __func__);
61 return -EINVAL;
62 }
63
64 expect_len = struct_size(ptr, country_list, ptr->country_count);
65 if (len < expect_len) {
66 rtw89_debug(rtwdev, mask: RTW89_DBG_ACPI, fmt: "%s: expect %u but length: %u\n",
67 __func__, expect_len, len);
68 return -EINVAL;
69 }
70
71 *policy_6ghz = kmemdup(p: ptr, size: expect_len, GFP_KERNEL);
72 if (!*policy_6ghz)
73 return -ENOMEM;
74
75 rtw89_hex_dump(rtwdev, mask: RTW89_DBG_ACPI, prefix_str: "policy_6ghz: ", buf: *policy_6ghz,
76 len: expect_len);
77 return 0;
78}
79
80int rtw89_acpi_evaluate_dsm(struct rtw89_dev *rtwdev,
81 enum rtw89_acpi_dsm_func func,
82 struct rtw89_acpi_dsm_result *res)
83{
84 union acpi_object *obj;
85 int ret;
86
87 obj = acpi_evaluate_dsm(ACPI_HANDLE(rtwdev->dev), guid: &rtw89_guid,
88 rev: 0, func, NULL);
89 if (!obj) {
90 rtw89_debug(rtwdev, mask: RTW89_DBG_ACPI,
91 fmt: "acpi dsm fail to evaluate func: %d\n", func);
92 return -ENOENT;
93 }
94
95 if (func == RTW89_ACPI_DSM_FUNC_6G_BP)
96 ret = rtw89_acpi_dsm_get_policy_6ghz(rtwdev, obj,
97 policy_6ghz: &res->u.policy_6ghz);
98 else
99 ret = rtw89_acpi_dsm_get_value(rtwdev, obj, value: &res->u.value);
100
101 ACPI_FREE(obj);
102 return ret;
103}
104

source code of linux/drivers/net/wireless/realtek/rtw89/acpi.c