1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver for Sophgo CV1800 series SoC RTC subsystem
4 *
5 * The RTC module comprises a 32kHz oscillator, Power-on-Reset (PoR) sub-module,
6 * HW state machine to control chip power-on, power-off and reset. Furthermore,
7 * the 8051 subsystem is located within RTCSYS including associated SRAM block.
8 *
9 * Copyright (C) 2025 Alexander Sverdlin <alexander.sverdlin@gmail.com>
10 *
11 */
12
13 #include <linux/mfd/core.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/property.h>
17
18 static struct resource cv1800_rtcsys_irq_resources[] = {
19 DEFINE_RES_IRQ_NAMED(0, "alarm"),
20 };
21
22 static const struct mfd_cell cv1800_rtcsys_subdev[] = {
23 {
24 .name = "cv1800b-rtc",
25 .num_resources = 1,
26 .resources = &cv1800_rtcsys_irq_resources[0],
27 },
28 };
29
cv1800_rtcsys_probe(struct platform_device * pdev)30 static int cv1800_rtcsys_probe(struct platform_device *pdev)
31 {
32 int irq;
33
34 irq = platform_get_irq_byname(pdev, "alarm");
35 if (irq < 0)
36 return irq;
37 cv1800_rtcsys_irq_resources[0].start = irq;
38 cv1800_rtcsys_irq_resources[0].end = irq;
39
40 return devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
41 cv1800_rtcsys_subdev,
42 ARRAY_SIZE(cv1800_rtcsys_subdev),
43 NULL, 0, NULL);
44 }
45
46 static const struct of_device_id cv1800_rtcsys_of_match[] = {
47 { .compatible = "sophgo,cv1800b-rtc" },
48 { /* sentinel */ }
49 };
50 MODULE_DEVICE_TABLE(of, cv1800_rtcsys_of_match);
51
52 static struct platform_driver cv1800_rtcsys_mfd = {
53 .probe = cv1800_rtcsys_probe,
54 .driver = {
55 .name = "cv1800_rtcsys",
56 .of_match_table = cv1800_rtcsys_of_match,
57 },
58 };
59 module_platform_driver(cv1800_rtcsys_mfd);
60
61 MODULE_AUTHOR("Alexander Sverdlin <alexander.sverdlin@gmail.com>");
62 MODULE_DESCRIPTION("Sophgo CV1800 series SoC RTC subsystem driver");
63 MODULE_LICENSE("GPL");
64