Add the rt linux 4.1.3-rt3 as base

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

diff --git a/kernel/drivers/iio/common/st_sensors/st_sensors_buffer.c b/kernel/drivers/iio/common/st_sensors/st_sensors_buffer.c
new file mode 100644 (file)
index 0000000..e18bc67
--- /dev/null
+++ b/kernel/drivers/iio/common/st_sensors/st_sensors_buffer.c
@@ -0,0 +1,128 @@
+/*
+ * STMicroelectronics sensors buffer 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/trigger.h>
+#include <linux/interrupt.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/irqreturn.h>
+
+#include <linux/iio/common/st_sensors.h>
+
+
+int st_sensors_get_buffer_element(struct iio_dev *indio_dev, u8 *buf)
+{
+       u8 *addr;
+       int i, n = 0, len;
+       struct st_sensor_data *sdata = iio_priv(indio_dev);
+       unsigned int num_data_channels = sdata->num_data_channels;
+       unsigned int byte_for_channel =
+                       indio_dev->channels[0].scan_type.storagebits >> 3;
+
+       addr = kmalloc(num_data_channels, GFP_KERNEL);
+       if (!addr) {
+               len = -ENOMEM;
+               goto st_sensors_get_buffer_element_error;
+       }
+
+       for (i = 0; i < num_data_channels; i++) {
+               if (test_bit(i, indio_dev->active_scan_mask)) {
+                       addr[n] = indio_dev->channels[i].address;
+                       n++;
+               }
+       }
+       switch (n) {
+       case 1:
+               len = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
+                       addr[0], byte_for_channel, buf, sdata->multiread_bit);
+               break;
+       case 2:
+               if ((addr[1] - addr[0]) == byte_for_channel) {
+                       len = sdata->tf->read_multiple_byte(&sdata->tb,
+                               sdata->dev, addr[0], byte_for_channel * n,
+                               buf, sdata->multiread_bit);
+               } else {
+                       u8 *rx_array;
+                       rx_array = kmalloc(byte_for_channel * num_data_channels,
+                                          GFP_KERNEL);
+                       if (!rx_array) {
+                               len = -ENOMEM;
+                               goto st_sensors_free_memory;
+                       }
+
+                       len = sdata->tf->read_multiple_byte(&sdata->tb,
+                               sdata->dev, addr[0],
+                               byte_for_channel * num_data_channels,
+                               rx_array, sdata->multiread_bit);
+                       if (len < 0) {
+                               kfree(rx_array);
+                               goto st_sensors_free_memory;
+                       }
+
+                       for (i = 0; i < n * byte_for_channel; i++) {
+                               if (i < n)
+                                       buf[i] = rx_array[i];
+                               else
+                                       buf[i] = rx_array[n + i];
+                       }
+                       kfree(rx_array);
+                       len = byte_for_channel * n;
+               }
+               break;
+       case 3:
+               len = sdata->tf->read_multiple_byte(&sdata->tb, sdata->dev,
+                       addr[0], byte_for_channel * num_data_channels,
+                       buf, sdata->multiread_bit);
+               break;
+       default:
+               len = -EINVAL;
+               goto st_sensors_free_memory;
+       }
+       if (len != byte_for_channel * n) {
+               len = -EIO;
+               goto st_sensors_free_memory;
+       }
+
+st_sensors_free_memory:
+       kfree(addr);
+st_sensors_get_buffer_element_error:
+       return len;
+}
+EXPORT_SYMBOL(st_sensors_get_buffer_element);
+
+irqreturn_t st_sensors_trigger_handler(int irq, void *p)
+{
+       int len;
+       struct iio_poll_func *pf = p;
+       struct iio_dev *indio_dev = pf->indio_dev;
+       struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+       len = st_sensors_get_buffer_element(indio_dev, sdata->buffer_data);
+       if (len < 0)
+               goto st_sensors_get_buffer_element_error;
+
+       iio_push_to_buffers_with_timestamp(indio_dev, sdata->buffer_data,
+               pf->timestamp);
+
+st_sensors_get_buffer_element_error:
+       iio_trigger_notify_done(indio_dev->trig);
+
+       return IRQ_HANDLED;
+}
+EXPORT_SYMBOL(st_sensors_trigger_handler);
+
+MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics ST-sensors buffer");
+MODULE_LICENSE("GPL v2");