1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2024 Linaro Ltd.
4 */
5
6 #include <linux/device.h>
7 #include <linux/mod_devicetable.h>
8 #include <linux/module.h>
9 #include <linux/pci-pwrctrl.h>
10 #include <linux/platform_device.h>
11 #include <linux/property.h>
12 #include <linux/pwrseq/consumer.h>
13 #include <linux/slab.h>
14 #include <linux/types.h>
15
16 struct pwrseq_pwrctrl {
17 struct pci_pwrctrl pwrctrl;
18 struct pwrseq_desc *pwrseq;
19 };
20
21 struct pwrseq_pwrctrl_pdata {
22 const char *target;
23 /*
24 * Called before doing anything else to perform device-specific
25 * verification between requesting the power sequencing handle.
26 */
27 int (*validate_device)(struct device *dev);
28 };
29
pwrseq_pwrctrl_qcm_wcn_validate_device(struct device * dev)30 static int pwrseq_pwrctrl_qcm_wcn_validate_device(struct device *dev)
31 {
32 /*
33 * Old device trees for some platforms already define wifi nodes for
34 * the WCN family of chips since before power sequencing was added
35 * upstream.
36 *
37 * These nodes don't consume the regulator outputs from the PMU, and
38 * if we allow this driver to bind to one of such "incomplete" nodes,
39 * we'll see a kernel log error about the indefinite probe deferral.
40 *
41 * Check the existence of the regulator supply that exists on all
42 * WCN models before moving forward.
43 */
44 if (!device_property_present(dev, "vddaon-supply"))
45 return -ENODEV;
46
47 return 0;
48 }
49
50 static const struct pwrseq_pwrctrl_pdata pwrseq_pwrctrl_qcom_wcn_pdata = {
51 .target = "wlan",
52 .validate_device = pwrseq_pwrctrl_qcm_wcn_validate_device,
53 };
54
pwrseq_pwrctrl_power_on(struct pci_pwrctrl * pwrctrl)55 static int pwrseq_pwrctrl_power_on(struct pci_pwrctrl *pwrctrl)
56 {
57 struct pwrseq_pwrctrl *pwrseq = container_of(pwrctrl,
58 struct pwrseq_pwrctrl, pwrctrl);
59
60 return pwrseq_power_on(pwrseq->pwrseq);
61 }
62
pwrseq_pwrctrl_power_off(struct pci_pwrctrl * pwrctrl)63 static int pwrseq_pwrctrl_power_off(struct pci_pwrctrl *pwrctrl)
64 {
65 struct pwrseq_pwrctrl *pwrseq = container_of(pwrctrl,
66 struct pwrseq_pwrctrl, pwrctrl);
67
68 return pwrseq_power_off(pwrseq->pwrseq);
69 }
70
pwrseq_pwrctrl_probe(struct platform_device * pdev)71 static int pwrseq_pwrctrl_probe(struct platform_device *pdev)
72 {
73 const struct pwrseq_pwrctrl_pdata *pdata;
74 struct pwrseq_pwrctrl *pwrseq;
75 struct device *dev = &pdev->dev;
76 int ret;
77
78 pdata = device_get_match_data(dev);
79 if (!pdata || !pdata->target)
80 return -EINVAL;
81
82 if (pdata->validate_device) {
83 ret = pdata->validate_device(dev);
84 if (ret)
85 return ret;
86 }
87
88 pwrseq = devm_kzalloc(dev, sizeof(*pwrseq), GFP_KERNEL);
89 if (!pwrseq)
90 return -ENOMEM;
91
92 pwrseq->pwrseq = devm_pwrseq_get(dev, pdata->target);
93 if (IS_ERR(pwrseq->pwrseq))
94 return dev_err_probe(dev, PTR_ERR(pwrseq->pwrseq),
95 "Failed to get the power sequencer\n");
96
97 pwrseq->pwrctrl.power_on = pwrseq_pwrctrl_power_on;
98 pwrseq->pwrctrl.power_off = pwrseq_pwrctrl_power_off;
99
100 pci_pwrctrl_init(&pwrseq->pwrctrl, dev);
101
102 ret = devm_pci_pwrctrl_device_set_ready(dev, &pwrseq->pwrctrl);
103 if (ret)
104 return dev_err_probe(dev, ret,
105 "Failed to register the pwrctrl wrapper\n");
106
107 return 0;
108 }
109
110 static const struct of_device_id pwrseq_pwrctrl_of_match[] = {
111 {
112 /* ATH11K in QCA6390 package. */
113 .compatible = "pci17cb,1101",
114 .data = &pwrseq_pwrctrl_qcom_wcn_pdata,
115 },
116 {
117 /* ATH11K in WCN6855 package. */
118 .compatible = "pci17cb,1103",
119 .data = &pwrseq_pwrctrl_qcom_wcn_pdata,
120 },
121 {
122 /* ATH12K in WCN7850 package. */
123 .compatible = "pci17cb,1107",
124 .data = &pwrseq_pwrctrl_qcom_wcn_pdata,
125 },
126 { }
127 };
128 MODULE_DEVICE_TABLE(of, pwrseq_pwrctrl_of_match);
129
130 static struct platform_driver pwrseq_pwrctrl_driver = {
131 .driver = {
132 .name = "pci-pwrctrl-pwrseq",
133 .of_match_table = pwrseq_pwrctrl_of_match,
134 },
135 .probe = pwrseq_pwrctrl_probe,
136 };
137 module_platform_driver(pwrseq_pwrctrl_driver);
138
139 MODULE_AUTHOR("Bartosz Golaszewski <bartosz.golaszewski@linaro.org>");
140 MODULE_DESCRIPTION("Generic PCI Power Control module for power sequenced devices");
141 MODULE_LICENSE("GPL");
142