1 // SPDX-License-Identifier: (GPL-2.0+ OR MIT)
2 /*
3 * Copyright (c) 2022 Rockchip Electronics Co., Ltd.
4 */
5
6 #include <linux/interrupt.h>
7 #include <linux/irq.h>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/mfd/syscon.h>
11 #include <linux/of_address.h>
12 #include <linux/of_device.h>
13 #include <linux/of_irq.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/regmap.h>
17
18 struct rknpor_powergood_info {
19 int irq;
20 irq_handler_t isr;
21 struct regmap *grf;
22 u32 grf_offset;
23 u8 status_bits_shift;
24 };
25
rv1106_npor_powergood_isr(int irq,void * data)26 static irqreturn_t rv1106_npor_powergood_isr(int irq, void *data)
27 {
28 struct rknpor_powergood_info *powergood = data;
29 u32 voltage = 0;
30
31 while (!voltage) {
32 regmap_read(powergood->grf, powergood->grf_offset, &voltage);
33 voltage = (voltage >> powergood->status_bits_shift) & 0x1;
34 }
35
36 pr_err("%s voltage jitter detected\n", __func__);
37
38 return IRQ_HANDLED;
39 }
40
41 static struct rknpor_powergood_info rv1106_soc_data = {
42 .grf_offset = 0x20020,
43 .status_bits_shift = 4,
44 .isr = rv1106_npor_powergood_isr,
45 };
46
47 static const struct of_device_id rockchip_npor_powergood_dt_match[] = {
48 {
49 .compatible = "rockchip,rv1106-npor-powergood",
50 .data = &rv1106_soc_data
51 },
52 {},
53 };
54
rockchip_npor_powergood_probe(struct platform_device * pdev)55 static int rockchip_npor_powergood_probe(struct platform_device *pdev)
56 {
57 struct rknpor_powergood_info *powergood;
58 const struct of_device_id *match;
59 struct device *dev = &pdev->dev;
60 int ret;
61
62 match = of_match_node(rockchip_npor_powergood_dt_match, pdev->dev.of_node);
63 powergood = (struct rknpor_powergood_info *)match->data;
64
65 if (!powergood)
66 return -EINVAL;
67
68 if (dev->parent && dev->parent->of_node) {
69 powergood->grf = syscon_node_to_regmap(dev->parent->of_node);
70 if (IS_ERR(powergood->grf))
71 return dev_err_probe(&pdev->dev, PTR_ERR(powergood->grf), "fail to find grf\n");
72 }
73
74 powergood->irq = platform_get_irq(pdev, 0);
75 if (powergood->irq < 0)
76 return powergood->irq;
77
78 ret = devm_request_irq(&pdev->dev, powergood->irq, powergood->isr, 0, "rknpor_powergood", powergood);
79 if (ret)
80 return dev_err_probe(&pdev->dev, ret, "request irq fail\n");
81
82 dev_info(&pdev->dev, "probe success!\n");
83
84 return 0;
85 }
86
87 static struct platform_driver rockchip_npor_powergood_driver = {
88 .probe = rockchip_npor_powergood_probe,
89 .driver = {
90 .name = "rockchip,rknpor-powergood",
91 .of_match_table = rockchip_npor_powergood_dt_match,
92 },
93 };
94
rockchip_npor_powergood_init(void)95 static int __init rockchip_npor_powergood_init(void)
96 {
97 return platform_driver_register(&rockchip_npor_powergood_driver);
98 }
99 subsys_initcall_sync(rockchip_npor_powergood_init);
100 MODULE_DESCRIPTION("Rockchip NPOR Powergood");
101 MODULE_LICENSE("GPL");
102