1// SPDX-License-Identifier: GPL-2.0
2/*
3 *  pcap rtc code for Motorola EZX phones
4 *
5 *  Copyright (c) 2008 guiming zhuo <gmzhuo@gmail.com>
6 *  Copyright (c) 2009 Daniel Ribeiro <drwyrm@gmail.com>
7 *
8 *  Based on Motorola's rtc.c Copyright (c) 2003-2005 Motorola
9 */
10
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/init.h>
14#include <linux/mfd/ezx-pcap.h>
15#include <linux/rtc.h>
16#include <linux/slab.h>
17#include <linux/platform_device.h>
18
19struct pcap_rtc {
20	struct pcap_chip *pcap;
21	struct rtc_device *rtc;
22};
23
24static irqreturn_t pcap_rtc_irq(int irq, void *_pcap_rtc)
25{
26	struct pcap_rtc *pcap_rtc = _pcap_rtc;
27	unsigned long rtc_events;
28
29	if (irq == pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ))
30		rtc_events = RTC_IRQF | RTC_UF;
31	else if (irq == pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA))
32		rtc_events = RTC_IRQF | RTC_AF;
33	else
34		rtc_events = 0;
35
36	rtc_update_irq(pcap_rtc->rtc, 1, rtc_events);
37	return IRQ_HANDLED;
38}
39
40static int pcap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
41{
42	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
43	struct rtc_time *tm = &alrm->time;
44	unsigned long secs;
45	u32 tod;	/* time of day, seconds since midnight */
46	u32 days;	/* days since 1/1/1970 */
47
48	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TODA, &tod);
49	secs = tod & PCAP_RTC_TOD_MASK;
50
51	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, &days);
52	secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
53
54	rtc_time64_to_tm(secs, tm);
55
56	return 0;
57}
58
59static int pcap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
60{
61	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
62	unsigned long secs = rtc_tm_to_time64(&alrm->time);
63	u32 tod, days;
64
65	tod = secs % SEC_PER_DAY;
66	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TODA, tod);
67
68	days = secs / SEC_PER_DAY;
69	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, days);
70
71	return 0;
72}
73
74static int pcap_rtc_read_time(struct device *dev, struct rtc_time *tm)
75{
76	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
77	unsigned long secs;
78	u32 tod, days;
79
80	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TOD, &tod);
81	secs = tod & PCAP_RTC_TOD_MASK;
82
83	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAY, &days);
84	secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
85
86	rtc_time64_to_tm(secs, tm);
87
88	return 0;
89}
90
91static int pcap_rtc_set_time(struct device *dev, struct rtc_time *tm)
92{
93	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
94	unsigned long secs = rtc_tm_to_time64(tm);
95	u32 tod, days;
96
97	tod = secs % SEC_PER_DAY;
98	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TOD, tod);
99
100	days = secs / SEC_PER_DAY;
101	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAY, days);
102
103	return 0;
104}
105
106static int pcap_rtc_irq_enable(struct device *dev, int pirq, unsigned int en)
107{
108	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
109
110	if (en)
111		enable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
112	else
113		disable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
114
115	return 0;
116}
117
118static int pcap_rtc_alarm_irq_enable(struct device *dev, unsigned int en)
119{
120	return pcap_rtc_irq_enable(dev, PCAP_IRQ_TODA, en);
121}
122
123static const struct rtc_class_ops pcap_rtc_ops = {
124	.read_time = pcap_rtc_read_time,
125	.set_time = pcap_rtc_set_time,
126	.read_alarm = pcap_rtc_read_alarm,
127	.set_alarm = pcap_rtc_set_alarm,
128	.alarm_irq_enable = pcap_rtc_alarm_irq_enable,
129};
130
131static int __init pcap_rtc_probe(struct platform_device *pdev)
132{
133	struct pcap_rtc *pcap_rtc;
134	int timer_irq, alarm_irq;
135	int err = -ENOMEM;
136
137	pcap_rtc = devm_kzalloc(&pdev->dev, sizeof(struct pcap_rtc),
138				GFP_KERNEL);
139	if (!pcap_rtc)
140		return err;
141
142	pcap_rtc->pcap = dev_get_drvdata(pdev->dev.parent);
143
144	platform_set_drvdata(pdev, pcap_rtc);
145
146	pcap_rtc->rtc = devm_rtc_allocate_device(&pdev->dev);
147	if (IS_ERR(pcap_rtc->rtc))
148		return PTR_ERR(pcap_rtc->rtc);
149
150	pcap_rtc->rtc->ops = &pcap_rtc_ops;
151	pcap_rtc->rtc->range_max = (1 << 14) * 86400ULL - 1;
152
153	timer_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ);
154	alarm_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA);
155
156	err = devm_request_irq(&pdev->dev, timer_irq, pcap_rtc_irq, 0,
157				"RTC Timer", pcap_rtc);
158	if (err)
159		return err;
160
161	err = devm_request_irq(&pdev->dev, alarm_irq, pcap_rtc_irq, 0,
162				"RTC Alarm", pcap_rtc);
163	if (err)
164		return err;
165
166	return devm_rtc_register_device(pcap_rtc->rtc);
167}
168
169static struct platform_driver pcap_rtc_driver = {
170	.driver = {
171		.name  = "pcap-rtc",
172	},
173};
174
175module_platform_driver_probe(pcap_rtc_driver, pcap_rtc_probe);
176
177MODULE_DESCRIPTION("Motorola pcap rtc driver");
178MODULE_AUTHOR("guiming zhuo <gmzhuo@gmail.com>");
179MODULE_LICENSE("GPL");
180