path: root/recipes/linux/linux-gumstix-2.6.15/rmk-2022-2-rtctime-sa110-pxa255-driver.patch

Index: linux-2.6.15gum/drivers/char/sa1100-rtc.c
===================================================================
--- /dev/null
+++ linux-2.6.15gum/drivers/char/sa1100-rtc.c
@@ -0,0 +1,297 @@
+/*
+ *	Real Time Clock interface for Linux on StrongARM SA1100
+ *
+ *	Copyright (c) 2000 Nils Faerber
+ *
+ *	Based on rtc.c by Paul Gortmaker
+ *	Date/time conversion routines taken from arch/arm/kernel/time.c
+ *			by Linus Torvalds and Russel King
+ *		and the GNU C Library
+ *	( ... I love the GPL ... just take what you need! ;)
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ *
+ *	1.00	2001-06-08	Nicolas Pitre <nico@cam.org>
+ *	- added periodic timer capability using OSMR1
+ *	- flag compatibility with other RTC chips
+ *	- permission checks for ioctls
+ *	- major cleanup, partial rewrite
+ *
+ *	0.03	2001-03-07	CIH <cih@coventive.com>
+ *	- Modify the bug setups RTC clock.
+ *
+ *	0.02	2001-02-27	Nils Faerber <nils@@kernelconcepts.de>
+ *	- removed mktime(), added alarm irq clear
+ *
+ *	0.01	2000-10-01	Nils Faerber <nils@@kernelconcepts.de>
+ *	- initial release
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/miscdevice.h>
+#include <linux/string.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <linux/proc_fs.h>
+#include <linux/interrupt.h>
+#include <linux/rtc.h>
+
+#ifdef CONFIG_ARCH_PXA
+#include <asm/arch/pxa-regs.h>
+#endif
+
+#include <asm/bitops.h>
+#include <asm/hardware.h>
+#include <asm/irq.h>
+#include <asm/rtc.h>
+
+#define TIMER_FREQ		3686400
+
+#define RTC_DEF_DIVIDER		32768 - 1
+#define RTC_DEF_TRIM		0
+
+/* Those are the bits from a classic RTC we want to mimic */
+#define RTC_IRQF		0x80	/* any of the following 3 is active */
+#define RTC_PF			0x40
+#define RTC_AF			0x20
+#define RTC_UF			0x10
+
+static unsigned long rtc_freq = 1024;
+static struct rtc_time rtc_alarm = {
+	.tm_year	= 0,
+	.tm_mon		= 0,
+	.tm_mday	= 0,
+	.tm_hour	= 0,
+	.tm_mon		= 0,
+	.tm_sec		= 0,
+};
+
+extern spinlock_t rtc_lock;
+
+static int rtc_update_alarm(struct rtc_time *alrm)
+{
+	struct rtc_time alarm_tm, now_tm;
+	unsigned long now, time;
+	int ret;
+
+	printk("Updating alarm\n");
+	do {
+		now = RCNR;
+		rtc_time_to_tm(now, &now_tm);
+		rtc_next_alarm_time(&alarm_tm, &now_tm, alrm);
+		ret = rtc_tm_to_time(&alarm_tm, &time);
+		if (ret != 0)
+			break;
+
+		RTSR = RTSR & (RTSR_HZE|RTSR_ALE|RTSR_AL);
+		RTAR = time;
+	} while (now != RCNR);
+	printk("set RTAR to %lx, now is %lx\n", time, now);
+
+	return ret;
+}
+
+static irqreturn_t rtc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	unsigned int rtsr;
+	unsigned long events = 0;
+
+	spin_lock(&rtc_lock);
+
+	rtsr = RTSR;
+	/* clear interrupt sources */
+	RTSR = 0;
+	RTSR = (RTSR_AL|RTSR_HZ) & (rtsr >> 2);
+
+	printk(KERN_CRIT "rtc_interrupt: rtsr = %x\n", rtsr);
+
+	/* clear alarm interrupt if it has occurred */
+	if (rtsr & RTSR_AL) {
+		printk(KERN_CRIT "ALARM INTRRUPT\n");
+		rtsr &= ~RTSR_ALE;
+	}
+	RTSR = rtsr & (RTSR_ALE|RTSR_HZE);
+
+	/* update irq data & counter */
+	if (rtsr & RTSR_AL)
+		events |= (RTC_AF|RTC_IRQF);
+	if (rtsr & RTSR_HZ)
+		events |= (RTC_UF|RTC_IRQF);
+
+	rtc_update(1, events);
+
+	if (rtsr & RTSR_AL && rtc_periodic_alarm(&rtc_alarm))
+		rtc_update_alarm(&rtc_alarm);
+
+	spin_unlock(&rtc_lock);
+
+	return IRQ_HANDLED;
+}
+
+
+static int sa1100_rtc_open(void)
+{
+	int ret;
+
+	ret = request_irq(IRQ_RTC1Hz, rtc_interrupt, SA_INTERRUPT, "rtc 1Hz", NULL);
+	if (ret) {
+		printk(KERN_ERR "rtc: IRQ%d already in use.\n", IRQ_RTC1Hz);
+		goto fail_ui;
+	}
+	ret = request_irq(IRQ_RTCAlrm, rtc_interrupt, SA_INTERRUPT, "rtc Alrm", NULL);
+	if (ret) {
+		printk(KERN_ERR "rtc: IRQ%d already in use.\n", IRQ_RTCAlrm);
+		goto fail_ai;
+	}
+	return 0;
+
+ fail_ai:
+	free_irq(IRQ_RTC1Hz, NULL);
+ fail_ui:
+	return ret;
+}
+
+static void sa1100_rtc_release(void)
+{
+	spin_lock_irq (&rtc_lock);
+	RTSR = 0;
+	OIER &= ~OIER_E1;
+	OSSR = OSSR_M1;
+	spin_unlock_irq (&rtc_lock);
+
+	free_irq(IRQ_RTCAlrm, NULL);
+	free_irq(IRQ_RTC1Hz, NULL);
+}
+
+static int sa1100_rtc_ioctl(unsigned int cmd, unsigned long arg)
+{
+	switch (cmd) {
+	case RTC_AIE_OFF:
+		spin_lock_irq(&rtc_lock);
+		RTSR &= ~RTSR_ALE;
+		spin_unlock_irq(&rtc_lock);
+		return 0;
+	case RTC_AIE_ON:
+		spin_lock_irq(&rtc_lock);
+		RTSR |= RTSR_ALE;
+		spin_unlock_irq(&rtc_lock);
+		return 0;
+	case RTC_UIE_OFF:
+		spin_lock_irq(&rtc_lock);
+		RTSR &= ~RTSR_HZE;
+		spin_unlock_irq(&rtc_lock);
+		return 0;
+	case RTC_UIE_ON:
+		spin_lock_irq(&rtc_lock);
+		RTSR |= RTSR_HZE;
+		spin_unlock_irq(&rtc_lock);
+		return 0;
+	}
+	return -EINVAL;
+}
+
+static void sa1100_rtc_read_time(struct rtc_time *tm)
+{
+	rtc_time_to_tm(RCNR, tm);
+}
+
+static int sa1100_rtc_set_time(struct rtc_time *tm)
+{
+	unsigned long time;
+	int ret;
+
+	ret = rtc_tm_to_time(tm, &time);
+	if (ret == 0)
+		RCNR = time;
+	return ret;
+}
+
+static void sa1100_rtc_read_alarm(struct rtc_wkalrm *alrm)
+{
+	memcpy(&alrm->time, &rtc_alarm, sizeof(struct rtc_time));
+	alrm->pending = RTSR & RTSR_AL ? 1 : 0;
+}
+
+static int sa1100_rtc_set_alarm(struct rtc_wkalrm *alrm)
+{
+	int ret;
+
+	printk("sa1100_rtc_set_alarm\n");
+
+	spin_lock_irq(&rtc_lock);
+	ret = rtc_update_alarm(&alrm->time);
+	if (ret == 0) {
+		memcpy(&rtc_alarm, &alrm->time, sizeof(struct rtc_time));
+
+		if (alrm->enabled)
+			enable_irq_wake(IRQ_RTCAlrm);
+		else
+			disable_irq_wake(IRQ_RTCAlrm);
+	}
+	spin_unlock_irq(&rtc_lock);
+
+	return ret;
+}
+
+static int sa1100_rtc_proc(char *buf)
+{
+	char *p = buf;
+
+	p += sprintf(p, "trim/divider\t: 0x%08x\n", RTTR);
+	p += sprintf(p, "alarm_IRQ\t: %s\n", (RTSR & RTSR_ALE) ? "yes" : "no" );
+	p += sprintf(p, "update_IRQ\t: %s\n", (RTSR & RTSR_HZE) ? "yes" : "no");
+	p += sprintf(p, "periodic_IRQ\t: %s\n", (OIER & OIER_E1) ? "yes" : "no");
+	p += sprintf(p, "periodic_freq\t: %ld\n", rtc_freq);
+
+	return p - buf;
+}
+
+static struct rtc_ops sa1100_rtc_ops = {
+	.owner		= THIS_MODULE,
+	.open		= sa1100_rtc_open,
+	.release	= sa1100_rtc_release,
+	.ioctl		= sa1100_rtc_ioctl,
+
+	.read_time	= sa1100_rtc_read_time,
+	.set_time	= sa1100_rtc_set_time,
+	.read_alarm	= sa1100_rtc_read_alarm,
+	.set_alarm	= sa1100_rtc_set_alarm,
+	.proc		= sa1100_rtc_proc,
+};
+
+static int __init rtc_init(void)
+{
+	/*
+	 * According to the manual we should be able to let RTTR be zero
+	 * and then a default diviser for a 32.768KHz clock is used.
+	 * Apparently this doesn't work, at least for my SA1110 rev 5.
+	 * If the clock divider is uninitialized then reset it to the
+	 * default value to get the 1Hz clock.
+	 */
+	if (RTTR == 0) {
+		RTTR = RTC_DEF_DIVIDER + (RTC_DEF_TRIM << 16);
+		printk(KERN_WARNING "rtc: warning: initializing default clock divider/trim value\n");
+		/*  The current RTC value probably doesn't make sense either */
+		RCNR = 0;
+	}
+
+	register_rtc(&sa1100_rtc_ops);
+
+	return 0;
+}
+
+static void __exit rtc_exit(void)
+{
+	unregister_rtc(&sa1100_rtc_ops);
+}
+
+module_init(rtc_init);
+module_exit(rtc_exit);
+
+MODULE_AUTHOR("Nils Faerber <nils@@kernelconcepts.de>");
+MODULE_DESCRIPTION("SA1100 Realtime Clock Driver (RTC)");
+MODULE_LICENSE("GPL");		/* so says the header */
Index: linux-2.6.15gum/drivers/char/Makefile
===================================================================
--- linux-2.6.15gum.orig/drivers/char/Makefile
+++ linux-2.6.15gum/drivers/char/Makefile
@@ -60,6 +60,7 @@ obj-$(CONFIG_RTC) += rtc.o
 obj-$(CONFIG_HPET) += hpet.o
 obj-$(CONFIG_GEN_RTC) += genrtc.o
 obj-$(CONFIG_EFI_RTC) += efirtc.o
+obj-$(CONFIG_SA1100_RTC) += sa1100-rtc.o
 obj-$(CONFIG_SGI_DS1286) += ds1286.o
 obj-$(CONFIG_SGI_IP27_RTC) += ip27-rtc.o
 obj-$(CONFIG_DS1302) += ds1302.o
Index: linux-2.6.15gum/drivers/char/Kconfig
===================================================================
--- linux-2.6.15gum.orig/drivers/char/Kconfig
+++ linux-2.6.15gum/drivers/char/Kconfig
@@ -790,6 +790,10 @@ config COBALT_LCD
 	  This option enables support for the LCD display and buttons found
 	  on Cobalt systems through a misc device.
 
+config SA1100_RTC
+	tristate "SA1100/PXA2xx Real Time Clock"
+	depends on ARCH_SA1100 || ARCH_PXA
+
 config DTLK
 	tristate "Double Talk PC internal speech card support"
 	help