xref: /openbmc/linux/drivers/rtc/rtc-pcap.c (revision 83268fa6)
1 /*
2  *  pcap rtc code for Motorola EZX phones
3  *
4  *  Copyright (c) 2008 guiming zhuo <gmzhuo@gmail.com>
5  *  Copyright (c) 2009 Daniel Ribeiro <drwyrm@gmail.com>
6  *
7  *  Based on Motorola's rtc.c Copyright (c) 2003-2005 Motorola
8  *
9  *  This program is free software; you can redistribute it and/or modify
10  *  it under the terms of the GNU General Public License version 2 as
11  *  published by the Free Software Foundation.
12  *
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/mfd/ezx-pcap.h>
19 #include <linux/rtc.h>
20 #include <linux/slab.h>
21 #include <linux/platform_device.h>
22 
23 struct pcap_rtc {
24 	struct pcap_chip *pcap;
25 	struct rtc_device *rtc;
26 };
27 
28 static irqreturn_t pcap_rtc_irq(int irq, void *_pcap_rtc)
29 {
30 	struct pcap_rtc *pcap_rtc = _pcap_rtc;
31 	unsigned long rtc_events;
32 
33 	if (irq == pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ))
34 		rtc_events = RTC_IRQF | RTC_UF;
35 	else if (irq == pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA))
36 		rtc_events = RTC_IRQF | RTC_AF;
37 	else
38 		rtc_events = 0;
39 
40 	rtc_update_irq(pcap_rtc->rtc, 1, rtc_events);
41 	return IRQ_HANDLED;
42 }
43 
44 static int pcap_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
45 {
46 	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
47 	struct rtc_time *tm = &alrm->time;
48 	unsigned long secs;
49 	u32 tod;	/* time of day, seconds since midnight */
50 	u32 days;	/* days since 1/1/1970 */
51 
52 	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TODA, &tod);
53 	secs = tod & PCAP_RTC_TOD_MASK;
54 
55 	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, &days);
56 	secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
57 
58 	rtc_time_to_tm(secs, tm);
59 
60 	return 0;
61 }
62 
63 static int pcap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
64 {
65 	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
66 	struct rtc_time *tm = &alrm->time;
67 	unsigned long secs;
68 	u32 tod, days;
69 
70 	rtc_tm_to_time(tm, &secs);
71 
72 	tod = secs % SEC_PER_DAY;
73 	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TODA, tod);
74 
75 	days = secs / SEC_PER_DAY;
76 	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, days);
77 
78 	return 0;
79 }
80 
81 static int pcap_rtc_read_time(struct device *dev, struct rtc_time *tm)
82 {
83 	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
84 	unsigned long secs;
85 	u32 tod, days;
86 
87 	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TOD, &tod);
88 	secs = tod & PCAP_RTC_TOD_MASK;
89 
90 	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAY, &days);
91 	secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
92 
93 	rtc_time_to_tm(secs, tm);
94 
95 	return 0;
96 }
97 
98 static int pcap_rtc_set_mmss(struct device *dev, unsigned long secs)
99 {
100 	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
101 	u32 tod, days;
102 
103 	tod = secs % SEC_PER_DAY;
104 	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TOD, tod);
105 
106 	days = secs / SEC_PER_DAY;
107 	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAY, days);
108 
109 	return 0;
110 }
111 
112 static int pcap_rtc_irq_enable(struct device *dev, int pirq, unsigned int en)
113 {
114 	struct pcap_rtc *pcap_rtc = dev_get_drvdata(dev);
115 
116 	if (en)
117 		enable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
118 	else
119 		disable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
120 
121 	return 0;
122 }
123 
124 static int pcap_rtc_alarm_irq_enable(struct device *dev, unsigned int en)
125 {
126 	return pcap_rtc_irq_enable(dev, PCAP_IRQ_TODA, en);
127 }
128 
129 static const struct rtc_class_ops pcap_rtc_ops = {
130 	.read_time = pcap_rtc_read_time,
131 	.read_alarm = pcap_rtc_read_alarm,
132 	.set_alarm = pcap_rtc_set_alarm,
133 	.set_mmss = pcap_rtc_set_mmss,
134 	.alarm_irq_enable = pcap_rtc_alarm_irq_enable,
135 };
136 
137 static int __init pcap_rtc_probe(struct platform_device *pdev)
138 {
139 	struct pcap_rtc *pcap_rtc;
140 	int timer_irq, alarm_irq;
141 	int err = -ENOMEM;
142 
143 	pcap_rtc = devm_kzalloc(&pdev->dev, sizeof(struct pcap_rtc),
144 				GFP_KERNEL);
145 	if (!pcap_rtc)
146 		return err;
147 
148 	pcap_rtc->pcap = dev_get_drvdata(pdev->dev.parent);
149 
150 	platform_set_drvdata(pdev, pcap_rtc);
151 
152 	pcap_rtc->rtc = devm_rtc_device_register(&pdev->dev, "pcap",
153 					&pcap_rtc_ops, THIS_MODULE);
154 	if (IS_ERR(pcap_rtc->rtc))
155 		return PTR_ERR(pcap_rtc->rtc);
156 
157 	timer_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ);
158 	alarm_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA);
159 
160 	err = devm_request_irq(&pdev->dev, timer_irq, pcap_rtc_irq, 0,
161 				"RTC Timer", pcap_rtc);
162 	if (err)
163 		return err;
164 
165 	err = devm_request_irq(&pdev->dev, alarm_irq, pcap_rtc_irq, 0,
166 				"RTC Alarm", pcap_rtc);
167 	if (err)
168 		return err;
169 
170 	return 0;
171 }
172 
173 static int __exit pcap_rtc_remove(struct platform_device *pdev)
174 {
175 	return 0;
176 }
177 
178 static struct platform_driver pcap_rtc_driver = {
179 	.remove = __exit_p(pcap_rtc_remove),
180 	.driver = {
181 		.name  = "pcap-rtc",
182 	},
183 };
184 
185 module_platform_driver_probe(pcap_rtc_driver, pcap_rtc_probe);
186 
187 MODULE_DESCRIPTION("Motorola pcap rtc driver");
188 MODULE_AUTHOR("guiming zhuo <gmzhuo@gmail.com>");
189 MODULE_LICENSE("GPL");
190