Commit 2027b1a2 authored by Petre Rodan's avatar Petre Rodan Committed by Jonathan Cameron
Browse files

iio: accel: bma220: reset registers during init stage 



Bring all configuration registers to default values during
device probe().
Remove trivial code duplication regarding bma220_power() in
_init()

Signed-off-by: default avatarPetre Rodan <petre.rodan@subdimension.ro>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent dfea5f18

drivers/iio/accel/bma220_core.c

+36 −8
Original line number Diff line number Diff line
@@ -29,12 +29,15 @@ 
#define BMA220_REG_ACCEL_Z			0x04

#define BMA220_REG_RANGE			0x11

#define BMA220_REG_SUSPEND			0x18

#define BMA220_REG_SOFTRESET			0x19



#define BMA220_CHIP_ID				0xDD

#define BMA220_READ_MASK			BIT(7)

#define BMA220_RANGE_MASK			GENMASK(1, 0)

#define BMA220_SUSPEND_SLEEP			0xFF

#define BMA220_SUSPEND_WAKE			0x00

#define BMA220_RESET_MODE			0xFF

#define BMA220_NONRESET_MODE			0x00



#define BMA220_DEVICE_NAME			"bma220"
@@ -203,6 +206,31 @@ static const struct iio_info bma220_info = { 
	.read_avail		= bma220_read_avail,

};



static int bma220_reset(struct spi_device *spi, bool up)

{

	int ret;

	unsigned int i;



	/*

	 * The chip can be reset by a simple register read.

	 * We need up to 2 register reads of the softreset register

	 * to make sure that the device is in the desired state.

	 */

	for (i = 0; i < 2; i++) {

		ret = bma220_read_reg(spi, BMA220_REG_SOFTRESET);

		if (ret < 0)

			return ret;



		if (up && ret == BMA220_RESET_MODE)

			return 0;



		if (!up && ret == BMA220_NONRESET_MODE)

			return 0;

	}



	return -EBUSY;

}



static int bma220_power(struct spi_device *spi, bool up)

{

	int ret;
@@ -247,14 +275,14 @@ static int bma220_init(struct spi_device *spi) 
	if (ret != BMA220_CHIP_ID)

		dev_info(dev, "Unknown chip found: 0x%02x\n", ret);



	/* Make sure the chip is powered on */

	ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);

	if (ret == BMA220_SUSPEND_WAKE)

		ret = bma220_read_reg(spi, BMA220_REG_SUSPEND);

	if (ret < 0)

		return ret;

	if (ret == BMA220_SUSPEND_WAKE)

		return -EBUSY;

	/* Make sure the chip is powered on and config registers are reset */

	ret = bma220_power(spi, true);

	if (ret)

		return dev_err_probe(dev, ret, "Failed to power-on chip\n");



	ret = bma220_reset(spi, true);

	if (ret)

		return dev_err_probe(dev, ret, "Failed to soft reset chip\n");



	return 0;

}