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authorWolfram Sang <w.sang@pengutronix.de>2012-05-30 00:07:38 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-30 01:22:33 +0200
commiteb86c3064b3c53837fdfea17df1483d825919894 (patch)
tree0d408fe43f43248477bb521fdd5b6856878199b0
parentrtc: ds1307: remove superfluous initialization (diff)
downloadlinux-eb86c3064b3c53837fdfea17df1483d825919894.tar.xz
linux-eb86c3064b3c53837fdfea17df1483d825919894.zip
rtc: ds1307: add trickle charger support
Some DS13XX devices have "trickle chargers". Its configuration register is at different locations, the setup is the same, though. Since the configuration is board specific, introduce a platform_data to this driver. Tested with a DS1339 on a custom board. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Cc: Alessandro Zummo <alessandro.zummo@towertech.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--drivers/rtc/rtc-ds1307.c19
-rw-r--r--include/linux/rtc/ds1307.h22
2 files changed, 38 insertions, 3 deletions
diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index 5dc1c7941199..836710ce750e 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -17,8 +17,7 @@
#include <linux/string.h>
#include <linux/rtc.h>
#include <linux/bcd.h>
-
-
+#include <linux/rtc/ds1307.h>
/*
* We can't determine type by probing, but if we expect pre-Linux code
@@ -92,7 +91,8 @@ enum ds_type {
# define DS1337_BIT_A2I 0x02
# define DS1337_BIT_A1I 0x01
#define DS1339_REG_ALARM1_SECS 0x07
-#define DS1339_REG_TRICKLE 0x10
+
+#define DS13XX_TRICKLE_CHARGER_MAGIC 0xa0
#define RX8025_REG_CTRL1 0x0e
# define RX8025_BIT_2412 0x20
@@ -124,6 +124,7 @@ struct chip_desc {
unsigned alarm:1;
u16 nvram_offset;
u16 nvram_size;
+ u16 trickle_charger_reg;
};
static const struct chip_desc chips[last_ds_type] = {
@@ -140,6 +141,13 @@ static const struct chip_desc chips[last_ds_type] = {
},
[ds_1339] = {
.alarm = 1,
+ .trickle_charger_reg = 0x10,
+ },
+ [ds_1340] = {
+ .trickle_charger_reg = 0x08,
+ },
+ [ds_1388] = {
+ .trickle_charger_reg = 0x0a,
},
[ds_3231] = {
.alarm = 1,
@@ -619,6 +627,7 @@ static int __devinit ds1307_probe(struct i2c_client *client,
struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
int want_irq = false;
unsigned char *buf;
+ struct ds1307_platform_data *pdata = client->dev.platform_data;
static const int bbsqi_bitpos[] = {
[ds_1337] = 0,
[ds_1339] = DS1339_BIT_BBSQI,
@@ -638,6 +647,10 @@ static int __devinit ds1307_probe(struct i2c_client *client,
ds1307->client = client;
ds1307->type = id->driver_data;
+ if (pdata && pdata->trickle_charger_setup && chip->trickle_charger_reg)
+ i2c_smbus_write_byte_data(client, chip->trickle_charger_reg,
+ DS13XX_TRICKLE_CHARGER_MAGIC | pdata->trickle_charger_setup);
+
buf = ds1307->regs;
if (i2c_check_functionality(adapter, I2C_FUNC_SMBUS_I2C_BLOCK)) {
ds1307->read_block_data = i2c_smbus_read_i2c_block_data;
diff --git a/include/linux/rtc/ds1307.h b/include/linux/rtc/ds1307.h
new file mode 100644
index 000000000000..291b1c490367
--- /dev/null
+++ b/include/linux/rtc/ds1307.h
@@ -0,0 +1,22 @@
+/*
+ * ds1307.h - platform_data for the ds1307 (and variants) rtc driver
+ * (C) Copyright 2012 by Wolfram Sang, Pengutronix e.K.
+ * same license as the driver
+ */
+
+#ifndef _LINUX_DS1307_H
+#define _LINUX_DS1307_H
+
+#include <linux/types.h>
+
+#define DS1307_TRICKLE_CHARGER_250_OHM 0x01
+#define DS1307_TRICKLE_CHARGER_2K_OHM 0x02
+#define DS1307_TRICKLE_CHARGER_4K_OHM 0x03
+#define DS1307_TRICKLE_CHARGER_NO_DIODE 0x04
+#define DS1307_TRICKLE_CHARGER_DIODE 0x08
+
+struct ds1307_platform_data {
+ u8 trickle_charger_setup;
+};
+
+#endif /* _LINUX_DS1307_H */