Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / iio / common / st_sensors / st_sensors_spi.c

diff --git a/kernel/drivers/iio/common/st_sensors/st_sensors_spi.c b/kernel/drivers/iio/common/st_sensors/st_sensors_spi.c
new file mode 100644 (file)
index 0000000..5b37737
--- /dev/null
+++ b/kernel/drivers/iio/common/st_sensors/st_sensors_spi.c
@@ -0,0 +1,122 @@
+/*
+ * 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);
+       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->dev = &spi->dev;
+       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");