1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2024 Linaro Ltd.
4 * Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
5 */
6
7 #include <linux/clk.h>
8 #include <linux/device.h>
9 #include <linux/mod_devicetable.h>
10 #include <linux/module.h>
11 #include <linux/pci-pwrctrl.h>
12 #include <linux/platform_device.h>
13 #include <linux/regulator/consumer.h>
14 #include <linux/slab.h>
15
16 struct pci_pwrctrl_slot_data {
17 struct pci_pwrctrl ctx;
18 struct regulator_bulk_data *supplies;
19 int num_supplies;
20 };
21
devm_pci_pwrctrl_slot_power_off(void * data)22 static void devm_pci_pwrctrl_slot_power_off(void *data)
23 {
24 struct pci_pwrctrl_slot_data *slot = data;
25
26 regulator_bulk_disable(slot->num_supplies, slot->supplies);
27 regulator_bulk_free(slot->num_supplies, slot->supplies);
28 }
29
pci_pwrctrl_slot_probe(struct platform_device * pdev)30 static int pci_pwrctrl_slot_probe(struct platform_device *pdev)
31 {
32 struct pci_pwrctrl_slot_data *slot;
33 struct device *dev = &pdev->dev;
34 struct clk *clk;
35 int ret;
36
37 slot = devm_kzalloc(dev, sizeof(*slot), GFP_KERNEL);
38 if (!slot)
39 return -ENOMEM;
40
41 ret = of_regulator_bulk_get_all(dev, dev_of_node(dev),
42 &slot->supplies);
43 if (ret < 0) {
44 dev_err_probe(dev, ret, "Failed to get slot regulators\n");
45 return ret;
46 }
47
48 slot->num_supplies = ret;
49 ret = regulator_bulk_enable(slot->num_supplies, slot->supplies);
50 if (ret < 0) {
51 dev_err_probe(dev, ret, "Failed to enable slot regulators\n");
52 goto err_regulator_free;
53 }
54
55 ret = devm_add_action_or_reset(dev, devm_pci_pwrctrl_slot_power_off,
56 slot);
57 if (ret)
58 goto err_regulator_disable;
59
60 clk = devm_clk_get_optional_enabled(dev, NULL);
61 if (IS_ERR(clk)) {
62 return dev_err_probe(dev, PTR_ERR(clk),
63 "Failed to enable slot clock\n");
64 }
65
66 pci_pwrctrl_init(&slot->ctx, dev);
67
68 ret = devm_pci_pwrctrl_device_set_ready(dev, &slot->ctx);
69 if (ret)
70 return dev_err_probe(dev, ret, "Failed to register pwrctrl driver\n");
71
72 return 0;
73
74 err_regulator_disable:
75 regulator_bulk_disable(slot->num_supplies, slot->supplies);
76 err_regulator_free:
77 regulator_bulk_free(slot->num_supplies, slot->supplies);
78
79 return ret;
80 }
81
82 static const struct of_device_id pci_pwrctrl_slot_of_match[] = {
83 {
84 .compatible = "pciclass,0604",
85 },
86 { }
87 };
88 MODULE_DEVICE_TABLE(of, pci_pwrctrl_slot_of_match);
89
90 static struct platform_driver pci_pwrctrl_slot_driver = {
91 .driver = {
92 .name = "pci-pwrctrl-slot",
93 .of_match_table = pci_pwrctrl_slot_of_match,
94 },
95 .probe = pci_pwrctrl_slot_probe,
96 };
97 module_platform_driver(pci_pwrctrl_slot_driver);
98
99 MODULE_AUTHOR("Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>");
100 MODULE_DESCRIPTION("Generic PCI Power Control driver for PCI Slots");
101 MODULE_LICENSE("GPL");
102