From eb86c3064b3c53837fdfea17df1483d825919894 Mon Sep 17 00:00:00 2001 From: Wolfram Sang Date: Tue, 29 May 2012 15:07:38 -0700 Subject: [PATCH] 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 Cc: Alessandro Zummo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rtc/rtc-ds1307.c | 19 ++++++++++++++++--- include/linux/rtc/ds1307.h | 22 ++++++++++++++++++++++ 2 files changed, 38 insertions(+), 3 deletions(-) create mode 100644 include/linux/rtc/ds1307.h 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 #include #include - - +#include /* * 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 + +#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 */