xref: /openbmc/linux/drivers/rtc/rtc-pcap.c (revision 275876e2)
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 platform_device *pdev = to_platform_device(dev);
47 	struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
48 	struct rtc_time *tm = &alrm->time;
49 	unsigned long secs;
50 	u32 tod;	/* time of day, seconds since midnight */
51 	u32 days;	/* days since 1/1/1970 */
52 
53 	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TODA, &tod);
54 	secs = tod & PCAP_RTC_TOD_MASK;
55 
56 	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, &days);
57 	secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
58 
59 	rtc_time_to_tm(secs, tm);
60 
61 	return 0;
62 }
63 
64 static int pcap_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
65 {
66 	struct platform_device *pdev = to_platform_device(dev);
67 	struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
68 	struct rtc_time *tm = &alrm->time;
69 	unsigned long secs;
70 	u32 tod, days;
71 
72 	rtc_tm_to_time(tm, &secs);
73 
74 	tod = secs % SEC_PER_DAY;
75 	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TODA, tod);
76 
77 	days = secs / SEC_PER_DAY;
78 	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAYA, days);
79 
80 	return 0;
81 }
82 
83 static int pcap_rtc_read_time(struct device *dev, struct rtc_time *tm)
84 {
85 	struct platform_device *pdev = to_platform_device(dev);
86 	struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
87 	unsigned long secs;
88 	u32 tod, days;
89 
90 	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_TOD, &tod);
91 	secs = tod & PCAP_RTC_TOD_MASK;
92 
93 	ezx_pcap_read(pcap_rtc->pcap, PCAP_REG_RTC_DAY, &days);
94 	secs += (days & PCAP_RTC_DAY_MASK) * SEC_PER_DAY;
95 
96 	rtc_time_to_tm(secs, tm);
97 
98 	return rtc_valid_tm(tm);
99 }
100 
101 static int pcap_rtc_set_mmss(struct device *dev, unsigned long secs)
102 {
103 	struct platform_device *pdev = to_platform_device(dev);
104 	struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
105 	u32 tod, days;
106 
107 	tod = secs % SEC_PER_DAY;
108 	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_TOD, tod);
109 
110 	days = secs / SEC_PER_DAY;
111 	ezx_pcap_write(pcap_rtc->pcap, PCAP_REG_RTC_DAY, days);
112 
113 	return 0;
114 }
115 
116 static int pcap_rtc_irq_enable(struct device *dev, int pirq, unsigned int en)
117 {
118 	struct platform_device *pdev = to_platform_device(dev);
119 	struct pcap_rtc *pcap_rtc = platform_get_drvdata(pdev);
120 
121 	if (en)
122 		enable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
123 	else
124 		disable_irq(pcap_to_irq(pcap_rtc->pcap, pirq));
125 
126 	return 0;
127 }
128 
129 static int pcap_rtc_alarm_irq_enable(struct device *dev, unsigned int en)
130 {
131 	return pcap_rtc_irq_enable(dev, PCAP_IRQ_TODA, en);
132 }
133 
134 static const struct rtc_class_ops pcap_rtc_ops = {
135 	.read_time = pcap_rtc_read_time,
136 	.read_alarm = pcap_rtc_read_alarm,
137 	.set_alarm = pcap_rtc_set_alarm,
138 	.set_mmss = pcap_rtc_set_mmss,
139 	.alarm_irq_enable = pcap_rtc_alarm_irq_enable,
140 };
141 
142 static int __init pcap_rtc_probe(struct platform_device *pdev)
143 {
144 	struct pcap_rtc *pcap_rtc;
145 	int timer_irq, alarm_irq;
146 	int err = -ENOMEM;
147 
148 	pcap_rtc = devm_kzalloc(&pdev->dev, sizeof(struct pcap_rtc),
149 				GFP_KERNEL);
150 	if (!pcap_rtc)
151 		return err;
152 
153 	pcap_rtc->pcap = dev_get_drvdata(pdev->dev.parent);
154 
155 	platform_set_drvdata(pdev, pcap_rtc);
156 
157 	pcap_rtc->rtc = devm_rtc_device_register(&pdev->dev, "pcap",
158 					&pcap_rtc_ops, THIS_MODULE);
159 	if (IS_ERR(pcap_rtc->rtc))
160 		return PTR_ERR(pcap_rtc->rtc);
161 
162 	timer_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_1HZ);
163 	alarm_irq = pcap_to_irq(pcap_rtc->pcap, PCAP_IRQ_TODA);
164 
165 	err = devm_request_irq(&pdev->dev, timer_irq, pcap_rtc_irq, 0,
166 				"RTC Timer", pcap_rtc);
167 	if (err)
168 		return err;
169 
170 	err = devm_request_irq(&pdev->dev, alarm_irq, pcap_rtc_irq, 0,
171 				"RTC Alarm", pcap_rtc);
172 	if (err)
173 		return err;
174 
175 	return 0;
176 }
177 
178 static int __exit pcap_rtc_remove(struct platform_device *pdev)
179 {
180 	return 0;
181 }
182 
183 static struct platform_driver pcap_rtc_driver = {
184 	.remove = __exit_p(pcap_rtc_remove),
185 	.driver = {
186 		.name  = "pcap-rtc",
187 		.owner = THIS_MODULE,
188 	},
189 };
190 
191 module_platform_driver_probe(pcap_rtc_driver, pcap_rtc_probe);
192 
193 MODULE_DESCRIPTION("Motorola pcap rtc driver");
194 MODULE_AUTHOR("guiming zhuo <gmzhuo@gmail.com>");
195 MODULE_LICENSE("GPL");
196