From 53e84b672c1a8190af2b376c35c7a39cf1214f59 Mon Sep 17 00:00:00 2001
From: David Brownell <david-b@pacbell.net>
Date: Wed, 23 Jul 2008 21:30:36 -0700
Subject: rtc: ds1305/ds1306 driver
Support the Dallas/Maxim DS1305 and DS1306 RTC chips. These use SPI, and
support alarms, NVRAM, and a trickle charger for use when their backup
power supply is a supercap or rechargeable cell.
This basic driver doesn't yet support suspend/resume or wakealarms.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
include/linux/spi/ds1305.h | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)
create mode 100644 include/linux/spi/ds1305.h
(limited to 'include/linux/spi/ds1305.h')
diff --git a/include/linux/spi/ds1305.h b/include/linux/spi/ds1305.h
new file mode 100644
index 000000000000..287ec830eab7
--- /dev/null
+++ b/include/linux/spi/ds1305.h
@@ -0,0 +1,35 @@
+#ifndef __LINUX_SPI_DS1305_H
+#define __LINUX_SPI_DS1305_H
+
+/*
+ * One-time configuration for ds1305 and ds1306 RTC chips.
+ *
+ * Put a pointer to this in spi_board_info.platform_data if you want to
+ * be sure that Linux (re)initializes this as needed ... after losing
+ * backup power, and potentially on the first boot.
+ */
+struct ds1305_platform_data {
+
+ /* Trickle charge configuration: it's OK to leave out the MAGIC
+ * bitmask; mask in either DS1 or DS2, and then one of 2K/4k/8K.
+ */
+#define DS1305_TRICKLE_MAGIC 0xa0
+#define DS1305_TRICKLE_DS2 0x08 /* two diodes */
+#define DS1305_TRICKLE_DS1 0x04 /* one diode */
+#define DS1305_TRICKLE_2K 0x01 /* 2 KOhm resistance */
+#define DS1305_TRICKLE_4K 0x02 /* 4 KOhm resistance */
+#define DS1305_TRICKLE_8K 0x03 /* 8 KOhm resistance */
+ u8 trickle;
+
+ /* set only on ds1306 parts */
+ bool is_ds1306;
+
+ /* ds1306 only: enable 1 Hz output */
+ bool en_1hz;
+
+ /* REVISIT: the driver currently expects nINT0 to be wired
+ * as the alarm IRQ. ALM1 may also need to be set up ...
+ */
+};
+
+#endif /* __LINUX_SPI_DS1305_H */
--
cgit v1.2.1