summaryrefslogtreecommitdiff
path: root/drivers/acpi/dptf/dptf_pch_fivr.c
blob: 4919e7abe93f47280157dcc91f10f09434951255 (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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
// SPDX-License-Identifier: GPL-2.0-only
/*
 * dptf_pch_fivr:  DPTF PCH FIVR Participant driver
 * Copyright (c) 2020, Intel Corporation.
 */

#include <linux/acpi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>

struct pch_fivr_resp {
	u64 status;
	u64 result;
};

static int pch_fivr_read(acpi_handle handle, char *method, struct pch_fivr_resp *fivr_resp)
{
	struct acpi_buffer resp = { sizeof(struct pch_fivr_resp), fivr_resp};
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_buffer format = { sizeof("NN"), "NN" };
	union acpi_object *obj;
	acpi_status status;
	int ret = -EFAULT;

	status = acpi_evaluate_object(handle, method, NULL, &buffer);
	if (ACPI_FAILURE(status))
		return ret;

	obj = buffer.pointer;
	if (!obj || obj->type != ACPI_TYPE_PACKAGE)
		goto release_buffer;

	status = acpi_extract_package(obj, &format, &resp);
	if (ACPI_FAILURE(status))
		goto release_buffer;

	if (fivr_resp->status)
		goto release_buffer;

	ret = 0;

release_buffer:
	kfree(buffer.pointer);
	return ret;
}

/*
 * Presentation of attributes which are defined for INTC10xx
 * They are:
 * freq_mhz_low_clock : Set PCH FIVR switching freq for
 *			FIVR clock 19.2MHz and 24MHz
 * freq_mhz_high_clock : Set PCH FIVR switching freq for
 *			FIVR clock 38.4MHz
 */
#define PCH_FIVR_SHOW(name, method) \
static ssize_t name##_show(struct device *dev,\
			   struct device_attribute *attr,\
			   char *buf)\
{\
	struct acpi_device *acpi_dev = dev_get_drvdata(dev);\
	struct pch_fivr_resp fivr_resp;\
	int status;\
\
	status = pch_fivr_read(acpi_dev->handle, #method, &fivr_resp);\
	if (status)\
		return status;\
\
	return sprintf(buf, "%llu\n", fivr_resp.result);\
}

#define PCH_FIVR_STORE(name, method) \
static ssize_t name##_store(struct device *dev,\
			    struct device_attribute *attr,\
			    const char *buf, size_t count)\
{\
	struct acpi_device *acpi_dev = dev_get_drvdata(dev);\
	acpi_status status;\
	u32 val;\
\
	if (kstrtouint(buf, 0, &val) < 0)\
		return -EINVAL;\
\
	status = acpi_execute_simple_method(acpi_dev->handle, #method, val);\
	if (ACPI_SUCCESS(status))\
		return count;\
\
	return -EINVAL;\
}

PCH_FIVR_SHOW(freq_mhz_low_clock, GFC0)
PCH_FIVR_SHOW(freq_mhz_high_clock, GFC1)
PCH_FIVR_SHOW(ssc_clock_info, GEMI)
PCH_FIVR_SHOW(fivr_switching_freq_mhz, GFCS)
PCH_FIVR_SHOW(fivr_switching_fault_status, GFFS)
PCH_FIVR_STORE(freq_mhz_low_clock, RFC0)
PCH_FIVR_STORE(freq_mhz_high_clock, RFC1)

static DEVICE_ATTR_RW(freq_mhz_low_clock);
static DEVICE_ATTR_RW(freq_mhz_high_clock);
static DEVICE_ATTR_RO(ssc_clock_info);
static DEVICE_ATTR_RO(fivr_switching_freq_mhz);
static DEVICE_ATTR_RO(fivr_switching_fault_status);

static struct attribute *fivr_attrs[] = {
	&dev_attr_freq_mhz_low_clock.attr,
	&dev_attr_freq_mhz_high_clock.attr,
	&dev_attr_ssc_clock_info.attr,
	&dev_attr_fivr_switching_freq_mhz.attr,
	&dev_attr_fivr_switching_fault_status.attr,
	NULL
};

static const struct attribute_group pch_fivr_attribute_group = {
	.attrs = fivr_attrs,
	.name = "pch_fivr_switch_frequency"
};

static int pch_fivr_add(struct platform_device *pdev)
{
	struct acpi_device *acpi_dev;
	unsigned long long ptype;
	acpi_status status;
	int result;

	acpi_dev = ACPI_COMPANION(&(pdev->dev));
	if (!acpi_dev)
		return -ENODEV;

	status = acpi_evaluate_integer(acpi_dev->handle, "PTYP", NULL, &ptype);
	if (ACPI_FAILURE(status) || ptype != 0x05)
		return -ENODEV;

	result = sysfs_create_group(&pdev->dev.kobj,
				    &pch_fivr_attribute_group);
	if (result)
		return result;

	platform_set_drvdata(pdev, acpi_dev);

	return 0;
}

static int pch_fivr_remove(struct platform_device *pdev)
{
	sysfs_remove_group(&pdev->dev.kobj, &pch_fivr_attribute_group);

	return 0;
}

static const struct acpi_device_id pch_fivr_device_ids[] = {
	{"INTC1045", 0},
	{"INTC1049", 0},
	{"INTC1064", 0},
	{"INTC10A3", 0},
	{"", 0},
};
MODULE_DEVICE_TABLE(acpi, pch_fivr_device_ids);

static struct platform_driver pch_fivr_driver = {
	.probe = pch_fivr_add,
	.remove = pch_fivr_remove,
	.driver = {
		.name = "dptf_pch_fivr",
		.acpi_match_table = pch_fivr_device_ids,
	},
};

module_platform_driver(pch_fivr_driver);

MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>");
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("ACPI DPTF PCH FIVR driver");