Commit f9e89579 authored by Michael Burian's avatar Michael Burian Committed by Greg Kroah-Hartman
Browse files

[PATCH] i2c: Extend ds1337 initialization 



Add code to handle case where board firmware does not start the
RTC.

Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
CC: James Chapman <jchapman@katalix.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 2e3e13f8

drivers/i2c/chips/ds1337.c

+31 −6
Original line number Diff line number Diff line
@@ -337,14 +337,39 @@ static int ds1337_detect(struct i2c_adapter *adapter, int address, int kind) 


static void ds1337_init_client(struct i2c_client *client)

{

	u8 status, control;



	/* On some boards, the RTC isn't configured by boot firmware.

	 * Handle that case by starting/configuring the RTC now.

	 */

	status = i2c_smbus_read_byte_data(client, DS1337_REG_STATUS);

	control = i2c_smbus_read_byte_data(client, DS1337_REG_CONTROL);



	if ((status & 0x80) || (control & 0x80)) {

		/* RTC not running */

		u8 buf[16];

		struct i2c_msg msg[1];



		dev_dbg(&client->dev, "%s: RTC not running!\n", __FUNCTION__);



		/* Initialize all, including STATUS and CONTROL to zero */

		memset(buf, 0, sizeof(buf));

		msg[0].addr = client->addr;

		msg[0].flags = 0;

		msg[0].len = sizeof(buf);

		msg[0].buf = &buf[0];



		i2c_transfer(client->adapter, msg, 1);

	} else {

		/* Running: ensure that device is set in 24-hour mode */

		s32 val;



	/* Ensure that device is set in 24-hour mode */

		val = i2c_smbus_read_byte_data(client, DS1337_REG_HOUR);

		if ((val >= 0) && (val & (1 << 6)))

			i2c_smbus_write_byte_data(client, DS1337_REG_HOUR,

						  val & 0x3f);

	}

}



static int ds1337_detach_client(struct i2c_client *client)

{