cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

rtc-pcf50633.c (7343B)


      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/* NXP PCF50633 RTC Driver
      3 *
      4 * (C) 2006-2008 by Openmoko, Inc.
      5 * Author: Balaji Rao <balajirrao@openmoko.org>
      6 * All rights reserved.
      7 *
      8 * Broken down from monstrous PCF50633 driver mainly by
      9 * Harald Welte, Andy Green and Werner Almesberger
     10 */
     11
     12#include <linux/kernel.h>
     13#include <linux/module.h>
     14#include <linux/init.h>
     15#include <linux/device.h>
     16#include <linux/slab.h>
     17#include <linux/platform_device.h>
     18#include <linux/rtc.h>
     19#include <linux/bcd.h>
     20#include <linux/err.h>
     21
     22#include <linux/mfd/pcf50633/core.h>
     23
     24#define PCF50633_REG_RTCSC	0x59 /* Second */
     25#define PCF50633_REG_RTCMN	0x5a /* Minute */
     26#define PCF50633_REG_RTCHR	0x5b /* Hour */
     27#define PCF50633_REG_RTCWD	0x5c /* Weekday */
     28#define PCF50633_REG_RTCDT	0x5d /* Day */
     29#define PCF50633_REG_RTCMT	0x5e /* Month */
     30#define PCF50633_REG_RTCYR	0x5f /* Year */
     31#define PCF50633_REG_RTCSCA	0x60 /* Alarm Second */
     32#define PCF50633_REG_RTCMNA	0x61 /* Alarm Minute */
     33#define PCF50633_REG_RTCHRA	0x62 /* Alarm Hour */
     34#define PCF50633_REG_RTCWDA	0x63 /* Alarm Weekday */
     35#define PCF50633_REG_RTCDTA	0x64 /* Alarm Day */
     36#define PCF50633_REG_RTCMTA	0x65 /* Alarm Month */
     37#define PCF50633_REG_RTCYRA	0x66 /* Alarm Year */
     38
     39enum pcf50633_time_indexes {
     40	PCF50633_TI_SEC,
     41	PCF50633_TI_MIN,
     42	PCF50633_TI_HOUR,
     43	PCF50633_TI_WKDAY,
     44	PCF50633_TI_DAY,
     45	PCF50633_TI_MONTH,
     46	PCF50633_TI_YEAR,
     47	PCF50633_TI_EXTENT /* always last */
     48};
     49
     50struct pcf50633_time {
     51	u_int8_t time[PCF50633_TI_EXTENT];
     52};
     53
     54struct pcf50633_rtc {
     55	int alarm_enabled;
     56	int alarm_pending;
     57
     58	struct pcf50633 *pcf;
     59	struct rtc_device *rtc_dev;
     60};
     61
     62static void pcf2rtc_time(struct rtc_time *rtc, struct pcf50633_time *pcf)
     63{
     64	rtc->tm_sec = bcd2bin(pcf->time[PCF50633_TI_SEC]);
     65	rtc->tm_min = bcd2bin(pcf->time[PCF50633_TI_MIN]);
     66	rtc->tm_hour = bcd2bin(pcf->time[PCF50633_TI_HOUR]);
     67	rtc->tm_wday = bcd2bin(pcf->time[PCF50633_TI_WKDAY]);
     68	rtc->tm_mday = bcd2bin(pcf->time[PCF50633_TI_DAY]);
     69	rtc->tm_mon = bcd2bin(pcf->time[PCF50633_TI_MONTH]) - 1;
     70	rtc->tm_year = bcd2bin(pcf->time[PCF50633_TI_YEAR]) + 100;
     71}
     72
     73static void rtc2pcf_time(struct pcf50633_time *pcf, struct rtc_time *rtc)
     74{
     75	pcf->time[PCF50633_TI_SEC] = bin2bcd(rtc->tm_sec);
     76	pcf->time[PCF50633_TI_MIN] = bin2bcd(rtc->tm_min);
     77	pcf->time[PCF50633_TI_HOUR] = bin2bcd(rtc->tm_hour);
     78	pcf->time[PCF50633_TI_WKDAY] = bin2bcd(rtc->tm_wday);
     79	pcf->time[PCF50633_TI_DAY] = bin2bcd(rtc->tm_mday);
     80	pcf->time[PCF50633_TI_MONTH] = bin2bcd(rtc->tm_mon + 1);
     81	pcf->time[PCF50633_TI_YEAR] = bin2bcd(rtc->tm_year % 100);
     82}
     83
     84static int
     85pcf50633_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
     86{
     87	struct pcf50633_rtc *rtc = dev_get_drvdata(dev);
     88	int err;
     89
     90	if (enabled)
     91		err = pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
     92	else
     93		err = pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
     94
     95	if (err < 0)
     96		return err;
     97
     98	rtc->alarm_enabled = enabled;
     99
    100	return 0;
    101}
    102
    103static int pcf50633_rtc_read_time(struct device *dev, struct rtc_time *tm)
    104{
    105	struct pcf50633_rtc *rtc;
    106	struct pcf50633_time pcf_tm;
    107	int ret;
    108
    109	rtc = dev_get_drvdata(dev);
    110
    111	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSC,
    112					    PCF50633_TI_EXTENT,
    113					    &pcf_tm.time[0]);
    114	if (ret != PCF50633_TI_EXTENT) {
    115		dev_err(dev, "Failed to read time\n");
    116		return -EIO;
    117	}
    118
    119	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
    120		pcf_tm.time[PCF50633_TI_DAY],
    121		pcf_tm.time[PCF50633_TI_MONTH],
    122		pcf_tm.time[PCF50633_TI_YEAR],
    123		pcf_tm.time[PCF50633_TI_HOUR],
    124		pcf_tm.time[PCF50633_TI_MIN],
    125		pcf_tm.time[PCF50633_TI_SEC]);
    126
    127	pcf2rtc_time(tm, &pcf_tm);
    128
    129	dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);
    130
    131	return 0;
    132}
    133
    134static int pcf50633_rtc_set_time(struct device *dev, struct rtc_time *tm)
    135{
    136	struct pcf50633_rtc *rtc;
    137	struct pcf50633_time pcf_tm;
    138	int alarm_masked, ret = 0;
    139
    140	rtc = dev_get_drvdata(dev);
    141
    142	dev_dbg(dev, "RTC_TIME: %ptRr\n", tm);
    143
    144	rtc2pcf_time(&pcf_tm, tm);
    145
    146	dev_dbg(dev, "PCF_TIME: %02x.%02x.%02x %02x:%02x:%02x\n",
    147		pcf_tm.time[PCF50633_TI_DAY],
    148		pcf_tm.time[PCF50633_TI_MONTH],
    149		pcf_tm.time[PCF50633_TI_YEAR],
    150		pcf_tm.time[PCF50633_TI_HOUR],
    151		pcf_tm.time[PCF50633_TI_MIN],
    152		pcf_tm.time[PCF50633_TI_SEC]);
    153
    154
    155	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
    156
    157	if (!alarm_masked)
    158		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
    159
    160	/* Returns 0 on success */
    161	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSC,
    162					     PCF50633_TI_EXTENT,
    163					     &pcf_tm.time[0]);
    164
    165	if (!alarm_masked)
    166		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
    167
    168	return ret;
    169}
    170
    171static int pcf50633_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
    172{
    173	struct pcf50633_rtc *rtc;
    174	struct pcf50633_time pcf_tm;
    175	int ret = 0;
    176
    177	rtc = dev_get_drvdata(dev);
    178
    179	alrm->enabled = rtc->alarm_enabled;
    180	alrm->pending = rtc->alarm_pending;
    181
    182	ret = pcf50633_read_block(rtc->pcf, PCF50633_REG_RTCSCA,
    183				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
    184	if (ret != PCF50633_TI_EXTENT) {
    185		dev_err(dev, "Failed to read time\n");
    186		return -EIO;
    187	}
    188
    189	pcf2rtc_time(&alrm->time, &pcf_tm);
    190
    191	return rtc_valid_tm(&alrm->time);
    192}
    193
    194static int pcf50633_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
    195{
    196	struct pcf50633_rtc *rtc;
    197	struct pcf50633_time pcf_tm;
    198	int alarm_masked, ret = 0;
    199
    200	rtc = dev_get_drvdata(dev);
    201
    202	rtc2pcf_time(&pcf_tm, &alrm->time);
    203
    204	/* do like mktime does and ignore tm_wday */
    205	pcf_tm.time[PCF50633_TI_WKDAY] = 7;
    206
    207	alarm_masked = pcf50633_irq_mask_get(rtc->pcf, PCF50633_IRQ_ALARM);
    208
    209	/* disable alarm interrupt */
    210	if (!alarm_masked)
    211		pcf50633_irq_mask(rtc->pcf, PCF50633_IRQ_ALARM);
    212
    213	/* Returns 0 on success */
    214	ret = pcf50633_write_block(rtc->pcf, PCF50633_REG_RTCSCA,
    215				PCF50633_TI_EXTENT, &pcf_tm.time[0]);
    216	if (!alrm->enabled)
    217		rtc->alarm_pending = 0;
    218
    219	if (!alarm_masked || alrm->enabled)
    220		pcf50633_irq_unmask(rtc->pcf, PCF50633_IRQ_ALARM);
    221	rtc->alarm_enabled = alrm->enabled;
    222
    223	return ret;
    224}
    225
    226static const struct rtc_class_ops pcf50633_rtc_ops = {
    227	.read_time		= pcf50633_rtc_read_time,
    228	.set_time		= pcf50633_rtc_set_time,
    229	.read_alarm		= pcf50633_rtc_read_alarm,
    230	.set_alarm		= pcf50633_rtc_set_alarm,
    231	.alarm_irq_enable	= pcf50633_rtc_alarm_irq_enable,
    232};
    233
    234static void pcf50633_rtc_irq(int irq, void *data)
    235{
    236	struct pcf50633_rtc *rtc = data;
    237
    238	rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
    239	rtc->alarm_pending = 1;
    240}
    241
    242static int pcf50633_rtc_probe(struct platform_device *pdev)
    243{
    244	struct pcf50633_rtc *rtc;
    245
    246	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
    247	if (!rtc)
    248		return -ENOMEM;
    249
    250	rtc->pcf = dev_to_pcf50633(pdev->dev.parent);
    251	platform_set_drvdata(pdev, rtc);
    252	rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, "pcf50633-rtc",
    253				&pcf50633_rtc_ops, THIS_MODULE);
    254
    255	if (IS_ERR(rtc->rtc_dev))
    256		return PTR_ERR(rtc->rtc_dev);
    257
    258	pcf50633_register_irq(rtc->pcf, PCF50633_IRQ_ALARM,
    259					pcf50633_rtc_irq, rtc);
    260	return 0;
    261}
    262
    263static int pcf50633_rtc_remove(struct platform_device *pdev)
    264{
    265	struct pcf50633_rtc *rtc;
    266
    267	rtc = platform_get_drvdata(pdev);
    268	pcf50633_free_irq(rtc->pcf, PCF50633_IRQ_ALARM);
    269
    270	return 0;
    271}
    272
    273static struct platform_driver pcf50633_rtc_driver = {
    274	.driver = {
    275		.name = "pcf50633-rtc",
    276	},
    277	.probe = pcf50633_rtc_probe,
    278	.remove = pcf50633_rtc_remove,
    279};
    280
    281module_platform_driver(pcf50633_rtc_driver);
    282
    283MODULE_DESCRIPTION("PCF50633 RTC driver");
    284MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
    285MODULE_LICENSE("GPL");
    286