[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / iio / common / st_sensors / st_sensors_spi.c

/*
 * STMicroelectronics sensors spi library driver
 *
 * Copyright 2012-2013 STMicroelectronics Inc.
 *
 * Denis Ciocca <denis.ciocca@st.com>
 *
 * Licensed under the GPL-2.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/iio/iio.h>

#include <linux/iio/common/st_sensors_spi.h>


#define ST_SENSORS_SPI_MULTIREAD	0xc0
#define ST_SENSORS_SPI_READ		0x80

static unsigned int st_sensors_spi_get_irq(struct iio_dev *indio_dev)
{
	struct st_sensor_data *sdata = iio_priv(indio_dev);

	return to_spi_device(sdata->dev)->irq;
}

static int st_sensors_spi_read(struct st_sensor_transfer_buffer *tb,
	struct device *dev, u8 reg_addr, int len, u8 *data, bool multiread_bit)
{
	int err;

	struct spi_transfer xfers[] = {
		{
			.tx_buf = tb->tx_buf,
			.bits_per_word = 8,
			.len = 1,
		},
		{
			.rx_buf = tb->rx_buf,
			.bits_per_word = 8,
			.len = len,
		}
	};

	mutex_lock(&tb->buf_lock);
	if ((multiread_bit) && (len > 1))
		tb->tx_buf[0] = reg_addr | ST_SENSORS_SPI_MULTIREAD;
	else
		tb->tx_buf[0] = reg_addr | ST_SENSORS_SPI_READ;

	err = spi_sync_transfer(to_spi_device(dev), xfers, ARRAY_SIZE(xfers));
	if (err)
		goto acc_spi_read_error;

	memcpy(data, tb->rx_buf, len*sizeof(u8));
	mutex_unlock(&tb->buf_lock);
	return len;

acc_spi_read_error:
	mutex_unlock(&tb->buf_lock);
	return err;
}

static int st_sensors_spi_read_byte(struct st_sensor_transfer_buffer *tb,
				struct device *dev, u8 reg_addr, u8 *res_byte)
{
	return st_sensors_spi_read(tb, dev, reg_addr, 1, res_byte, false);
}

static int st_sensors_spi_read_multiple_byte(
	struct st_sensor_transfer_buffer *tb, struct device *dev,
			u8 reg_addr, int len, u8 *data, bool multiread_bit)
{
	return st_sensors_spi_read(tb, dev, reg_addr, len, data, multiread_bit);
}

static int st_sensors_spi_write_byte(struct st_sensor_transfer_buffer *tb,
				struct device *dev, u8 reg_addr, u8 data)
{
	int err;

	struct spi_transfer xfers = {
		.tx_buf = tb->tx_buf,
		.bits_per_word = 8,
		.len = 2,
	};

	mutex_lock(&tb->buf_lock);
	tb->tx_buf[0] = reg_addr;
	tb->tx_buf[1] = data;

	err = spi_sync_transfer(to_spi_device(dev), &xfers, 1);
	mutex_unlock(&tb->buf_lock);

	return err;
}

static const struct st_sensor_transfer_function st_sensors_tf_spi = {
	.read_byte = st_sensors_spi_read_byte,
	.write_byte = st_sensors_spi_write_byte,
	.read_multiple_byte = st_sensors_spi_read_multiple_byte,
};

void st_sensors_spi_configure(struct iio_dev *indio_dev,
			struct spi_device *spi, struct st_sensor_data *sdata)
{
	spi_set_drvdata(spi, indio_dev);

	indio_dev->dev.parent = &spi->dev;
	indio_dev->name = spi->modalias;

	sdata->tf = &st_sensors_tf_spi;
	sdata->get_irq_data_ready = st_sensors_spi_get_irq;
}
EXPORT_SYMBOL(st_sensors_spi_configure);

MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
MODULE_DESCRIPTION("STMicroelectronics ST-sensors spi driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
23491b51 DC	1	/*
	2	* STMicroelectronics sensors spi library driver
	3	*
	4	* Copyright 2012-2013 STMicroelectronics Inc.
	5	*
	6	* Denis Ciocca <denis.ciocca@st.com>
	7	*
	8	* Licensed under the GPL-2.
	9	*/
	10
	11	#include <linux/kernel.h>
	12	#include <linux/module.h>
	13	#include <linux/slab.h>
	14	#include <linux/iio/iio.h>
	15
	16	#include <linux/iio/common/st_sensors_spi.h>
	17
	18
	19	#define ST_SENSORS_SPI_MULTIREAD 0xc0
	20	#define ST_SENSORS_SPI_READ 0x80
	21
	22	static unsigned int st_sensors_spi_get_irq(struct iio_dev *indio_dev)
	23	{
	24	struct st_sensor_data *sdata = iio_priv(indio_dev);
	25
	26	return to_spi_device(sdata->dev)->irq;
	27	}
	28
	29	static int st_sensors_spi_read(struct st_sensor_transfer_buffer *tb,
	30	struct device dev, u8 reg_addr, int len, u8 data, bool multiread_bit)
	31	{
23491b51 DC	32	int err;
	33
	34	struct spi_transfer xfers[] = {
	35	{
	36	.tx_buf = tb->tx_buf,
	37	.bits_per_word = 8,
	38	.len = 1,
	39	},
	40	{
	41	.rx_buf = tb->rx_buf,
	42	.bits_per_word = 8,
	43	.len = len,
	44	}
	45	};
	46
	47	mutex_lock(&tb->buf_lock);
	48	if ((multiread_bit) && (len > 1))
	49	tb->tx_buf[0] = reg_addr \| ST_SENSORS_SPI_MULTIREAD;
	50	else
	51	tb->tx_buf[0] = reg_addr \| ST_SENSORS_SPI_READ;
	52
43bb786a	53	err = spi_sync_transfer(to_spi_device(dev), xfers, ARRAY_SIZE(xfers));
23491b51 DC	54	if (err)
	55	goto acc_spi_read_error;
	56
	57	memcpy(data, tb->rx_buf, len*sizeof(u8));
	58	mutex_unlock(&tb->buf_lock);
	59	return len;
	60
	61	acc_spi_read_error:
	62	mutex_unlock(&tb->buf_lock);
	63	return err;
	64	}
	65
	66	static int st_sensors_spi_read_byte(struct st_sensor_transfer_buffer *tb,
	67	struct device dev, u8 reg_addr, u8 res_byte)
	68	{
	69	return st_sensors_spi_read(tb, dev, reg_addr, 1, res_byte, false);
	70	}
	71
	72	static int st_sensors_spi_read_multiple_byte(
	73	struct st_sensor_transfer_buffer tb, struct device dev,
	74	u8 reg_addr, int len, u8 *data, bool multiread_bit)
	75	{
	76	return st_sensors_spi_read(tb, dev, reg_addr, len, data, multiread_bit);
	77	}
	78
	79	static int st_sensors_spi_write_byte(struct st_sensor_transfer_buffer *tb,
	80	struct device *dev, u8 reg_addr, u8 data)
	81	{
23491b51 DC	82	int err;
	83
	84	struct spi_transfer xfers = {
	85	.tx_buf = tb->tx_buf,
	86	.bits_per_word = 8,
	87	.len = 2,
	88	};
	89
	90	mutex_lock(&tb->buf_lock);
	91	tb->tx_buf[0] = reg_addr;
	92	tb->tx_buf[1] = data;
	93
43bb786a	94	err = spi_sync_transfer(to_spi_device(dev), &xfers, 1);
23491b51 DC	95	mutex_unlock(&tb->buf_lock);
	96
	97	return err;
	98	}
	99
	100	static const struct st_sensor_transfer_function st_sensors_tf_spi = {
	101	.read_byte = st_sensors_spi_read_byte,
	102	.write_byte = st_sensors_spi_write_byte,
	103	.read_multiple_byte = st_sensors_spi_read_multiple_byte,
	104	};
	105
	106	void st_sensors_spi_configure(struct iio_dev *indio_dev,
	107	struct spi_device spi, struct st_sensor_data sdata)
	108	{
	109	spi_set_drvdata(spi, indio_dev);
	110
	111	indio_dev->dev.parent = &spi->dev;
	112	indio_dev->name = spi->modalias;
	113
	114	sdata->tf = &st_sensors_tf_spi;
	115	sdata->get_irq_data_ready = st_sensors_spi_get_irq;
	116	}
	117	EXPORT_SYMBOL(st_sensors_spi_configure);
	118
	119	MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
	120	MODULE_DESCRIPTION("STMicroelectronics ST-sensors spi driver");
	121	MODULE_LICENSE("GPL v2");