summaryrefslogtreecommitdiff
path: root/drivers/pci/pwrctl/pci-pwrctl-pwrseq.c
blob: 0e6bd47671c2e6e37863ccc59fbfbb97a5d1be39 (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2024 Linaro Ltd.
 */

#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/pci-pwrctl.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/pwrseq/consumer.h>
#include <linux/slab.h>
#include <linux/types.h>

struct pci_pwrctl_pwrseq_data {
	struct pci_pwrctl ctx;
	struct pwrseq_desc *pwrseq;
};

struct pci_pwrctl_pwrseq_pdata {
	const char *target;
	/*
	 * Called before doing anything else to perform device-specific
	 * verification between requesting the power sequencing handle.
	 */
	int (*validate_device)(struct device *dev);
};

static int pci_pwrctl_pwrseq_qcm_wcn_validate_device(struct device *dev)
{
	/*
	 * Old device trees for some platforms already define wifi nodes for
	 * the WCN family of chips since before power sequencing was added
	 * upstream.
	 *
	 * These nodes don't consume the regulator outputs from the PMU, and
	 * if we allow this driver to bind to one of such "incomplete" nodes,
	 * we'll see a kernel log error about the indefinite probe deferral.
	 *
	 * Check the existence of the regulator supply that exists on all
	 * WCN models before moving forward.
	 */
	if (!device_property_present(dev, "vddaon-supply"))
		return -ENODEV;

	return 0;
}

static const struct pci_pwrctl_pwrseq_pdata pci_pwrctl_pwrseq_qcom_wcn_pdata = {
	.target = "wlan",
	.validate_device = pci_pwrctl_pwrseq_qcm_wcn_validate_device,
};

static void devm_pci_pwrctl_pwrseq_power_off(void *data)
{
	struct pwrseq_desc *pwrseq = data;

	pwrseq_power_off(pwrseq);
}

static int pci_pwrctl_pwrseq_probe(struct platform_device *pdev)
{
	const struct pci_pwrctl_pwrseq_pdata *pdata;
	struct pci_pwrctl_pwrseq_data *data;
	struct device *dev = &pdev->dev;
	int ret;

	pdata = device_get_match_data(dev);
	if (!pdata || !pdata->target)
		return -EINVAL;

	if (pdata->validate_device) {
		ret = pdata->validate_device(dev);
		if (ret)
			return ret;
	}

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->pwrseq = devm_pwrseq_get(dev, pdata->target);
	if (IS_ERR(data->pwrseq))
		return dev_err_probe(dev, PTR_ERR(data->pwrseq),
				     "Failed to get the power sequencer\n");

	ret = pwrseq_power_on(data->pwrseq);
	if (ret)
		return dev_err_probe(dev, ret,
				     "Failed to power-on the device\n");

	ret = devm_add_action_or_reset(dev, devm_pci_pwrctl_pwrseq_power_off,
				       data->pwrseq);
	if (ret)
		return ret;

	pci_pwrctl_init(&data->ctx, dev);

	ret = devm_pci_pwrctl_device_set_ready(dev, &data->ctx);
	if (ret)
		return dev_err_probe(dev, ret,
				     "Failed to register the pwrctl wrapper\n");

	return 0;
}

static const struct of_device_id pci_pwrctl_pwrseq_of_match[] = {
	{
		/* ATH11K in QCA6390 package. */
		.compatible = "pci17cb,1101",
		.data = &pci_pwrctl_pwrseq_qcom_wcn_pdata,
	},
	{
		/* ATH11K in WCN6855 package. */
		.compatible = "pci17cb,1103",
		.data = &pci_pwrctl_pwrseq_qcom_wcn_pdata,
	},
	{
		/* ATH12K in WCN7850 package. */
		.compatible = "pci17cb,1107",
		.data = &pci_pwrctl_pwrseq_qcom_wcn_pdata,
	},
	{ }
};
MODULE_DEVICE_TABLE(of, pci_pwrctl_pwrseq_of_match);

static struct platform_driver pci_pwrctl_pwrseq_driver = {
	.driver = {
		.name = "pci-pwrctl-pwrseq",
		.of_match_table = pci_pwrctl_pwrseq_of_match,
	},
	.probe = pci_pwrctl_pwrseq_probe,
};
module_platform_driver(pci_pwrctl_pwrseq_driver);

MODULE_AUTHOR("Bartosz Golaszewski <bartosz.golaszewski@linaro.org>");
MODULE_DESCRIPTION("Generic PCI Power Control module for power sequenced devices");
MODULE_LICENSE("GPL");