aboutsummaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-sa1100/dma.c
diff options
context:
space:
mode:
authorRussell King <rmk@dyn-67.arm.linux.org.uk>2008-11-29 06:40:28 -0500
committerRussell King <rmk+kernel@arm.linux.org.uk>2008-11-29 13:42:40 -0500
commitdcea83adc666061864b82c96e059dffe7268b512 (patch)
tree4882086842f53bee3f6c655e6a3283effd3fbdff /arch/arm/mach-sa1100/dma.c
parentc72e005b099302b3c6bee8381396199b77b6dd4f (diff)
[ARM] Hide ISA DMA API when ISA_DMA_API is unset
When ISA_DMA_API is unset, we're not implementing the ISA DMA API, so there's no point in publishing the prototypes via asm/dma.h, nor including the machine dependent parts of that API. This allows us to remove a lot of mach/dma.h files which don't contain any useful code. Unfortunately though, some platforms put their own private non-ISA definitions into mach/dma.h, so we leave these behind and fix the appropriate #include statments. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-sa1100/dma.c')
-rw-r--r--arch/arm/mach-sa1100/dma.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/arm/mach-sa1100/dma.c b/arch/arm/mach-sa1100/dma.c
index f990a3e85846..3f445ffd99f8 100644
--- a/arch/arm/mach-sa1100/dma.c
+++ b/arch/arm/mach-sa1100/dma.c
@@ -19,7 +19,7 @@
19#include <asm/system.h> 19#include <asm/system.h>
20#include <asm/irq.h> 20#include <asm/irq.h>
21#include <mach/hardware.h> 21#include <mach/hardware.h>
22#include <asm/dma.h> 22#include <mach/dma.h>
23 23
24 24
25#undef DEBUG 25#undef DEBUG
404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831
/*
 * rtc-ds1305.c -- driver for DS1305 and DS1306 SPI RTC chips
 *
 * Copyright (C) 2008 David Brownell
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/bcd.h>
#include <linux/slab.h>
#include <linux/rtc.h>
#include <linux/workqueue.h>

#include <linux/spi/spi.h>
#include <linux/spi/ds1305.h>
#include <linux/module.h>


/*
 * Registers ... mask DS1305_WRITE into register address to write,
 * otherwise you're reading it.  All non-bitmask values are BCD.
 */
#define DS1305_WRITE		0x80


/* RTC date/time ... the main special cases are that we:
 *  - Need fancy "hours" encoding in 12hour mode
 *  - Don't rely on the "day-of-week" field (or tm_wday)
 *  - Are a 21st-century clock (2000 <= year < 2100)
 */
#define DS1305_RTC_LEN		7		/* bytes for RTC regs */

#define DS1305_SEC		0x00		/* register addresses */
#define DS1305_MIN		0x01
#define DS1305_HOUR		0x02
#	define DS1305_HR_12		0x40	/* set == 12 hr mode */
#	define DS1305_HR_PM		0x20	/* set == PM (12hr mode) */
#define DS1305_WDAY		0x03
#define DS1305_MDAY		0x04
#define DS1305_MON		0x05
#define DS1305_YEAR		0x06


/* The two alarms have only sec/min/hour/wday fields (ALM_LEN).
 * DS1305_ALM_DISABLE disables a match field (some combos are bad).
 *
 * NOTE that since we don't use WDAY, we limit ourselves to alarms
 * only one day into the future (vs potentially up to a week).
 *
 * NOTE ALSO that while we could generate once-a-second IRQs (UIE), we
 * don't currently support them.  We'd either need to do it only when
 * no alarm is pending (not the standard model), or to use the second
 * alarm (implying that this is a DS1305 not DS1306, *and* that either
 * it's wired up a second IRQ we know, or that INTCN is set)
 */
#define DS1305_ALM_LEN		4		/* bytes for ALM regs */
#define DS1305_ALM_DISABLE	0x80

#define DS1305_ALM0(r)		(0x07 + (r))	/* register addresses */
#define DS1305_ALM1(r)		(0x0b + (r))


/* three control registers */
#define DS1305_CONTROL_LEN	3		/* bytes of control regs */

#define DS1305_CONTROL		0x0f		/* register addresses */
#	define DS1305_nEOSC		0x80	/* low enables oscillator */
#	define DS1305_WP		0x40	/* write protect */
#	define DS1305_INTCN		0x04	/* clear == only int0 used */
#	define DS1306_1HZ		0x04	/* enable 1Hz output */
#	define DS1305_AEI1		0x02	/* enable ALM1 IRQ */
#	define DS1305_AEI0		0x01	/* enable ALM0 IRQ */
#define DS1305_STATUS		0x10
/* status has just AEIx bits, mirrored as IRQFx */
#define DS1305_TRICKLE		0x11
/* trickle bits are defined in <linux/spi/ds1305.h> */

/* a bunch of NVRAM */
#define DS1305_NVRAM_LEN	96		/* bytes of NVRAM */

#define DS1305_NVRAM		0x20		/* register addresses */


struct ds1305 {
	struct spi_device	*spi;
	struct rtc_device	*rtc;

	struct work_struct	work;

	unsigned long		flags;
#define FLAG_EXITING	0

	bool			hr12;
	u8			ctrl[DS1305_CONTROL_LEN];
};


/*----------------------------------------------------------------------*/

/*
 * Utilities ...  tolerate 12-hour AM/PM notation in case of non-Linux
 * software (like a bootloader) which may require it.
 */

static unsigned bcd2hour(u8 bcd)
{
	if (bcd & DS1305_HR_12) {
		unsigned	hour = 0;

		bcd &= ~DS1305_HR_12;
		if (bcd & DS1305_HR_PM) {
			hour = 12;
			bcd &= ~DS1305_HR_PM;
		}
		hour += bcd2bin(bcd);
		return hour - 1;
	}
	return bcd2bin(bcd);
}

static u8 hour2bcd(bool hr12, int hour)
{
	if (hr12) {
		hour++;
		if (hour <= 12)
			return DS1305_HR_12 | bin2bcd(hour);
		hour -= 12;
		return DS1305_HR_12 | DS1305_HR_PM | bin2bcd(hour);
	}
	return bin2bcd(hour);
}

/*----------------------------------------------------------------------*/

/*
 * Interface to RTC framework
 */

static int ds1305_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
	struct ds1305	*ds1305 = dev_get_drvdata(dev);
	u8		buf[2];
	long		err = -EINVAL;

	buf[0] = DS1305_WRITE | DS1305_CONTROL;
	buf[1] = ds1305->ctrl[0];

	if (enabled) {
		if (ds1305->ctrl[0] & DS1305_AEI0)
			goto done;
		buf[1] |= DS1305_AEI0;
	} else {
		if (!(buf[1] & DS1305_AEI0))
			goto done;
		buf[1] &= ~DS1305_AEI0;
	}
	err = spi_write_then_read(ds1305->spi, buf, sizeof buf, NULL, 0);
	if (err >= 0)
		ds1305->ctrl[0] = buf[1];
done:
	return err;

}


/*
 * Get/set of date and time is pretty normal.
 */

static int ds1305_get_time(struct device *dev, struct rtc_time *time)
{
	struct ds1305	*ds1305 = dev_get_drvdata(dev);
	u8		addr = DS1305_SEC;
	u8		buf[DS1305_RTC_LEN];
	int		status;

	/* Use write-then-read to get all the date/time registers
	 * since dma from stack is nonportable
	 */
	status = spi_write_then_read(ds1305->spi, &addr, sizeof addr,
			buf, sizeof buf);
	if (status < 0)
		return status;

	dev_vdbg(dev, "%s: %02x %02x %02x, %02x %02x %02x %02x\n",
		"read", buf[0], buf[1], buf[2], buf[3],
		buf[4], buf[5], buf[6]);

	/* Decode the registers */
	time->tm_sec = bcd2bin(buf[DS1305_SEC]);
	time->tm_min = bcd2bin(buf[DS1305_MIN]);
	time->tm_hour = bcd2hour(buf[DS1305_HOUR]);
	time->tm_wday = buf[DS1305_WDAY] - 1;
	time->tm_mday = bcd2bin(buf[DS1305_MDAY]);
	time->tm_mon = bcd2bin(buf[DS1305_MON]) - 1;
	time->tm_year = bcd2bin(buf[DS1305_YEAR]) + 100;

	dev_vdbg(dev, "%s secs=%d, mins=%d, "
		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
		"read", time->tm_sec, time->tm_min,
		time->tm_hour, time->tm_mday,
		time->tm_mon, time->tm_year, time->tm_wday);

	/* Time may not be set */
	return rtc_valid_tm(time);
}

static int ds1305_set_time(struct device *dev, struct rtc_time *time)
{
	struct ds1305	*ds1305 = dev_get_drvdata(dev);
	u8		buf[1 + DS1305_RTC_LEN];
	u8		*bp = buf;

	dev_vdbg(dev, "%s secs=%d, mins=%d, "
		"hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
		"write", time->tm_sec, time->tm_min,
		time->tm_hour, time->tm_mday,
		time->tm_mon, time->tm_year, time->tm_wday);

	/* Write registers starting at the first time/date address. */
	*bp++ = DS1305_WRITE | DS1305_SEC;

	*bp++ = bin2bcd(time->tm_sec);
	*bp++ = bin2bcd(time->tm_min);
	*bp++ = hour2bcd(ds1305->hr12, time->tm_hour);
	*bp++ = (time->tm_wday < 7) ? (time->tm_wday + 1) : 1;
	*bp++ = bin2bcd(time->tm_mday);
	*bp++ = bin2bcd(time->tm_mon + 1);
	*bp++ = bin2bcd(time->tm_year - 100);

	dev_dbg(dev, "%s: %02x %02x %02x, %02x %02x %02x %02x\n",
		"write", buf[1], buf[2], buf[3],
		buf[4], buf[5], buf[6], buf[7]);

	/* use write-then-read since dma from stack is nonportable */
	return spi_write_then_read(ds1305->spi, buf, sizeof buf,
			NULL, 0);
}

/*
 * Get/set of alarm is a bit funky:
 *
 * - First there's the inherent raciness of getting the (partitioned)
 *   status of an alarm that could trigger while we're reading parts
 *   of that status.
 *
 * - Second there's its limited range (we could increase it a bit by
 *   relying on WDAY), which means it will easily roll over.
 *
 * - Third there's the choice of two alarms and alarm signals.
 *   Here we use ALM0 and expect that nINT0 (open drain) is used;
 *   that's the only real option for DS1306 runtime alarms, and is
 *   natural on DS1305.
 *
 * - Fourth, there's also ALM1, and a second interrupt signal:
 *     + On DS1305 ALM1 uses nINT1 (when INTCN=1) else nINT0;
 *     + On DS1306 ALM1 only uses INT1 (an active high pulse)
 *       and it won't work when VCC1 is active.
 *
 *   So to be most general, we should probably set both alarms to the
 *   same value, letting ALM1 be the wakeup event source on DS1306
 *   and handling several wiring options on DS1305.
 *
 * - Fifth, we support the polled mode (as well as possible; why not?)
 *   even when no interrupt line is wired to an IRQ.
 */

/*
 * Context: caller holds rtc->ops_lock (to protect ds1305->ctrl)
 */
static int ds1305_get_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
	struct ds1305	*ds1305 = dev_get_drvdata(dev);
	struct spi_device *spi = ds1305->spi;
	u8		addr;
	int		status;
	u8		buf[DS1305_ALM_LEN];

	/* Refresh control register cache BEFORE reading ALM0 registers,
	 * since reading alarm registers acks any pending IRQ.  That
	 * makes returning "pending" status a bit of a lie, but that bit
	 * of EFI status is at best fragile anyway (given IRQ handlers).
	 */
	addr = DS1305_CONTROL;
	status = spi_write_then_read(spi, &addr, sizeof addr,
			ds1305->ctrl, sizeof ds1305->ctrl);
	if (status < 0)
		return status;

	alm->enabled = !!(ds1305->ctrl[0] & DS1305_AEI0);
	alm->pending = !!(ds1305->ctrl[1] & DS1305_AEI0);

	/* get and check ALM0 registers */
	addr = DS1305_ALM0(DS1305_SEC);
	status = spi_write_then_read(spi, &addr, sizeof addr,
			buf, sizeof buf);
	if (status < 0)
		return status;

	dev_vdbg(dev, "%s: %02x %02x %02x %02x\n",
		"alm0 read", buf[DS1305_SEC], buf[DS1305_MIN],
		buf[DS1305_HOUR], buf[DS1305_WDAY]);

	if ((DS1305_ALM_DISABLE & buf[DS1305_SEC])
			|| (DS1305_ALM_DISABLE & buf[DS1305_MIN])
			|| (DS1305_ALM_DISABLE & buf[DS1305_HOUR]))
		return -EIO;

	/* Stuff these values into alm->time and let RTC framework code
	 * fill in the rest ... and also handle rollover to tomorrow when
	 * that's needed.
	 */
	alm->time.tm_sec = bcd2bin(buf[DS1305_SEC]);
	alm->time.tm_min = bcd2bin(buf[DS1305_MIN]);
	alm->time.tm_hour = bcd2hour(buf[DS1305_HOUR]);
	alm->time.tm_mday = -1;
	alm->time.tm_mon = -1;
	alm->time.tm_year = -1;
	/* next three fields are unused by Linux */
	alm->time.tm_wday = -1;
	alm->time.tm_mday = -1;
	alm->time.tm_isdst = -1;

	return 0;
}

/*
 * Context: caller holds rtc->ops_lock (to protect ds1305->ctrl)
 */
static int ds1305_set_alarm(struct device *dev, struct rtc_wkalrm *alm)
{
	struct ds1305	*ds1305 = dev_get_drvdata(dev);
	struct spi_device *spi = ds1305->spi;
	unsigned long	now, later;
	struct rtc_time	tm;
	int		status;
	u8		buf[1 + DS1305_ALM_LEN];

	/* convert desired alarm to time_t */
	status = rtc_tm_to_time(&alm->time, &later);
	if (status < 0)
		return status;

	/* Read current time as time_t */
	status = ds1305_get_time(dev, &tm);
	if (status < 0)
		return status;
	status = rtc_tm_to_time(&tm, &now);
	if (status < 0)
		return status;

	/* make sure alarm fires within the next 24 hours */
	if (later <= now)
		return -EINVAL;
	if ((later - now) > 24 * 60 * 60)
		return -EDOM;

	/* disable alarm if needed */
	if (ds1305->ctrl[0] & DS1305_AEI0) {
		ds1305->ctrl[0] &= ~DS1305_AEI0;

		buf[0] = DS1305_WRITE | DS1305_CONTROL;
		buf[1] = ds1305->ctrl[0];
		status = spi_write_then_read(ds1305->spi, buf, 2, NULL, 0);
		if (status < 0)
			return status;
	}

	/* write alarm */
	buf[0] = DS1305_WRITE | DS1305_ALM0(DS1305_SEC);
	buf[1 + DS1305_SEC] = bin2bcd(alm->time.tm_sec);
	buf[1 + DS1305_MIN] = bin2bcd(alm->time.tm_min);
	buf[1 + DS1305_HOUR] = hour2bcd(ds1305->hr12, alm->time.tm_hour);
	buf[1 + DS1305_WDAY] = DS1305_ALM_DISABLE;

	dev_dbg(dev, "%s: %02x %02x %02x %02x\n",
		"alm0 write", buf[1 + DS1305_SEC], buf[1 + DS1305_MIN],
		buf[1 + DS1305_HOUR], buf[1 + DS1305_WDAY]);

	status = spi_write_then_read(spi, buf, sizeof buf, NULL, 0);
	if (status < 0)
		return status;

	/* enable alarm if requested */
	if (alm->enabled) {
		ds1305->ctrl[0] |= DS1305_AEI0;

		buf[0] = DS1305_WRITE | DS1305_CONTROL;
		buf[1] = ds1305->ctrl[0];
		status = spi_write_then_read(ds1305->spi, buf, 2, NULL, 0);
	}

	return status;
}

#ifdef CONFIG_PROC_FS

static int ds1305_proc(struct device *dev, struct seq_file *seq)
{
	struct ds1305	*ds1305 = dev_get_drvdata(dev);
	char		*diodes = "no";
	char		*resistors = "";

	/* ctrl[2] is treated as read-only; no locking needed */
	if ((ds1305->ctrl[2] & 0xf0) == DS1305_TRICKLE_MAGIC) {
		switch (ds1305->ctrl[2] & 0x0c) {
		case DS1305_TRICKLE_DS2:
			diodes = "2 diodes, ";
			break;
		case DS1305_TRICKLE_DS1:
			diodes = "1 diode, ";
			break;
		default:
			goto done;
		}
		switch (ds1305->ctrl[2] & 0x03) {
		case DS1305_TRICKLE_2K:
			resistors = "2k Ohm";
			break;
		case DS1305_TRICKLE_4K:
			resistors = "4k Ohm";
			break;
		case DS1305_TRICKLE_8K:
			resistors = "8k Ohm";
			break;
		default:
			diodes = "no";
			break;
		}
	}

done:
	return seq_printf(seq,
			"trickle_charge\t: %s%s\n",
			diodes, resistors);
}

#else
#define ds1305_proc	NULL
#endif

static const struct rtc_class_ops ds1305_ops = {
	.read_time	= ds1305_get_time,
	.set_time	= ds1305_set_time,
	.read_alarm	= ds1305_get_alarm,
	.set_alarm	= ds1305_set_alarm,
	.proc		= ds1305_proc,
	.alarm_irq_enable = ds1305_alarm_irq_enable,
};

static void ds1305_work(struct work_struct *work)
{
	struct ds1305	*ds1305 = container_of(work, struct ds1305, work);
	struct mutex	*lock = &ds1305->rtc->ops_lock;
	struct spi_device *spi = ds1305->spi;
	u8		buf[3];
	int		status;

	/* lock to protect ds1305->ctrl */
	mutex_lock(lock);

	/* Disable the IRQ, and clear its status ... for now, we "know"
	 * that if more than one alarm is active, they're in sync.
	 * Note that reading ALM data registers also clears IRQ status.
	 */
	ds1305->ctrl[0] &= ~(DS1305_AEI1 | DS1305_AEI0);
	ds1305->ctrl[1] = 0;

	buf[0] = DS1305_WRITE | DS1305_CONTROL;
	buf[1] = ds1305->ctrl[0];
	buf[2] = 0;

	status = spi_write_then_read(spi, buf, sizeof buf,
			NULL, 0);
	if (status < 0)
		dev_dbg(&spi->dev, "clear irq --> %d\n", status);

	mutex_unlock(lock);

	if (!test_bit(FLAG_EXITING, &ds1305->flags))
		enable_irq(spi->irq);

	rtc_update_irq(ds1305->rtc, 1, RTC_AF | RTC_IRQF);
}

/*
 * This "real" IRQ handler hands off to a workqueue mostly to allow
 * mutex locking for ds1305->ctrl ... unlike I2C, we could issue async
 * I/O requests in IRQ context (to clear the IRQ status).
 */
static irqreturn_t ds1305_irq(int irq, void *p)
{
	struct ds1305		*ds1305 = p;

	disable_irq(irq);
	schedule_work(&ds1305->work);
	return IRQ_HANDLED;
}

/*----------------------------------------------------------------------*/

/*
 * Interface for NVRAM
 */

static void msg_init(struct spi_message *m, struct spi_transfer *x,
		u8 *addr, size_t count, char *tx, char *rx)
{
	spi_message_init(m);
	memset(x, 0, 2 * sizeof(*x));

	x->tx_buf = addr;
	x->len = 1;
	spi_message_add_tail(x, m);

	x++;

	x->tx_buf = tx;
	x->rx_buf = rx;
	x->len = count;
	spi_message_add_tail(x, m);
}

static ssize_t
ds1305_nvram_read(struct file *filp, struct kobject *kobj,
		struct bin_attribute *attr,
		char *buf, loff_t off, size_t count)
{
	struct spi_device	*spi;
	u8			addr;
	struct spi_message	m;
	struct spi_transfer	x[2];
	int			status;

	spi = container_of(kobj, struct spi_device, dev.kobj);

	if (unlikely(off >= DS1305_NVRAM_LEN))
		return 0;
	if (count >= DS1305_NVRAM_LEN)
		count = DS1305_NVRAM_LEN;
	if ((off + count) > DS1305_NVRAM_LEN)
		count = DS1305_NVRAM_LEN - off;
	if (unlikely(!count))
		return count;

	addr = DS1305_NVRAM + off;
	msg_init(&m, x, &addr, count, NULL, buf);

	status = spi_sync(spi, &m);
	if (status < 0)
		dev_err(&spi->dev, "nvram %s error %d\n", "read", status);
	return (status < 0) ? status : count;
}

static ssize_t
ds1305_nvram_write(struct file *filp, struct kobject *kobj,
		struct bin_attribute *attr,
		char *buf, loff_t off, size_t count)
{
	struct spi_device	*spi;
	u8			addr;
	struct spi_message	m;
	struct spi_transfer	x[2];
	int			status;

	spi = container_of(kobj, struct spi_device, dev.kobj);

	if (unlikely(off >= DS1305_NVRAM_LEN))
		return -EFBIG;
	if (count >= DS1305_NVRAM_LEN)
		count = DS1305_NVRAM_LEN;
	if ((off + count) > DS1305_NVRAM_LEN)
		count = DS1305_NVRAM_LEN - off;
	if (unlikely(!count))
		return count;

	addr = (DS1305_WRITE | DS1305_NVRAM) + off;
	msg_init(&m, x, &addr, count, buf, NULL);

	status = spi_sync(spi, &m);
	if (status < 0)
		dev_err(&spi->dev, "nvram %s error %d\n", "write", status);
	return (status < 0) ? status : count;
}

static struct bin_attribute nvram = {
	.attr.name	= "nvram",
	.attr.mode	= S_IRUGO | S_IWUSR,
	.read		= ds1305_nvram_read,
	.write		= ds1305_nvram_write,
	.size		= DS1305_NVRAM_LEN,
};

/*----------------------------------------------------------------------*/

/*
 * Interface to SPI stack
 */

static int __devinit ds1305_probe(struct spi_device *spi)
{
	struct ds1305			*ds1305;
	int				status;
	u8				addr, value;
	struct ds1305_platform_data	*pdata = spi->dev.platform_data;
	bool				write_ctrl = false;

	/* Sanity check board setup data.  This may be hooked up