xref: /linux/drivers/soc/sophgo/cv1800-rtcsys.c (revision 297d9111e9fcf47dd1dcc6f79bba915f35378d01)
1*c8754c7dSAlexander Sverdlin // SPDX-License-Identifier: GPL-2.0
2*c8754c7dSAlexander Sverdlin /*
3*c8754c7dSAlexander Sverdlin  * Driver for Sophgo CV1800 series SoC RTC subsystem
4*c8754c7dSAlexander Sverdlin  *
5*c8754c7dSAlexander Sverdlin  * The RTC module comprises a 32kHz oscillator, Power-on-Reset (PoR) sub-module,
6*c8754c7dSAlexander Sverdlin  * HW state machine to control chip power-on, power-off and reset. Furthermore,
7*c8754c7dSAlexander Sverdlin  * the 8051 subsystem is located within RTCSYS including associated SRAM block.
8*c8754c7dSAlexander Sverdlin  *
9*c8754c7dSAlexander Sverdlin  * Copyright (C) 2025 Alexander Sverdlin <alexander.sverdlin@gmail.com>
10*c8754c7dSAlexander Sverdlin  *
11*c8754c7dSAlexander Sverdlin  */
12*c8754c7dSAlexander Sverdlin 
13*c8754c7dSAlexander Sverdlin #include <linux/mfd/core.h>
14*c8754c7dSAlexander Sverdlin #include <linux/module.h>
15*c8754c7dSAlexander Sverdlin #include <linux/of.h>
16*c8754c7dSAlexander Sverdlin #include <linux/property.h>
17*c8754c7dSAlexander Sverdlin 
18*c8754c7dSAlexander Sverdlin static struct resource cv1800_rtcsys_irq_resources[] = {
19*c8754c7dSAlexander Sverdlin 	DEFINE_RES_IRQ_NAMED(0, "alarm"),
20*c8754c7dSAlexander Sverdlin };
21*c8754c7dSAlexander Sverdlin 
22*c8754c7dSAlexander Sverdlin static const struct mfd_cell cv1800_rtcsys_subdev[] = {
23*c8754c7dSAlexander Sverdlin 	{
24*c8754c7dSAlexander Sverdlin 		.name = "cv1800b-rtc",
25*c8754c7dSAlexander Sverdlin 		.num_resources = 1,
26*c8754c7dSAlexander Sverdlin 		.resources = &cv1800_rtcsys_irq_resources[0],
27*c8754c7dSAlexander Sverdlin 	},
28*c8754c7dSAlexander Sverdlin };
29*c8754c7dSAlexander Sverdlin 
cv1800_rtcsys_probe(struct platform_device * pdev)30*c8754c7dSAlexander Sverdlin static int cv1800_rtcsys_probe(struct platform_device *pdev)
31*c8754c7dSAlexander Sverdlin {
32*c8754c7dSAlexander Sverdlin 	int irq;
33*c8754c7dSAlexander Sverdlin 
34*c8754c7dSAlexander Sverdlin 	irq = platform_get_irq_byname(pdev, "alarm");
35*c8754c7dSAlexander Sverdlin 	if (irq < 0)
36*c8754c7dSAlexander Sverdlin 		return irq;
37*c8754c7dSAlexander Sverdlin 	cv1800_rtcsys_irq_resources[0].start = irq;
38*c8754c7dSAlexander Sverdlin 	cv1800_rtcsys_irq_resources[0].end = irq;
39*c8754c7dSAlexander Sverdlin 
40*c8754c7dSAlexander Sverdlin 	return devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
41*c8754c7dSAlexander Sverdlin 				    cv1800_rtcsys_subdev,
42*c8754c7dSAlexander Sverdlin 				    ARRAY_SIZE(cv1800_rtcsys_subdev),
43*c8754c7dSAlexander Sverdlin 				    NULL, 0, NULL);
44*c8754c7dSAlexander Sverdlin }
45*c8754c7dSAlexander Sverdlin 
46*c8754c7dSAlexander Sverdlin static const struct of_device_id cv1800_rtcsys_of_match[] = {
47*c8754c7dSAlexander Sverdlin 	{ .compatible = "sophgo,cv1800b-rtc" },
48*c8754c7dSAlexander Sverdlin 	{ /* sentinel */ }
49*c8754c7dSAlexander Sverdlin };
50*c8754c7dSAlexander Sverdlin MODULE_DEVICE_TABLE(of, cv1800_rtcsys_of_match);
51*c8754c7dSAlexander Sverdlin 
52*c8754c7dSAlexander Sverdlin static struct platform_driver cv1800_rtcsys_mfd = {
53*c8754c7dSAlexander Sverdlin 	.probe	= cv1800_rtcsys_probe,
54*c8754c7dSAlexander Sverdlin 	.driver	= {
55*c8754c7dSAlexander Sverdlin 		.name		= "cv1800_rtcsys",
56*c8754c7dSAlexander Sverdlin 		.of_match_table	= cv1800_rtcsys_of_match,
57*c8754c7dSAlexander Sverdlin 	},
58*c8754c7dSAlexander Sverdlin };
59*c8754c7dSAlexander Sverdlin module_platform_driver(cv1800_rtcsys_mfd);
60*c8754c7dSAlexander Sverdlin 
61*c8754c7dSAlexander Sverdlin MODULE_AUTHOR("Alexander Sverdlin <alexander.sverdlin@gmail.com>");
62*c8754c7dSAlexander Sverdlin MODULE_DESCRIPTION("Sophgo CV1800 series SoC RTC subsystem driver");
63*c8754c7dSAlexander Sverdlin MODULE_LICENSE("GPL");
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