--- /dev/null
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+#include <linux/workqueue.h>
+#include <linux/mutex.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/list.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+#include "../ring_sw.h"
+#include "../accel/accel.h"
+#include "../trigger.h"
+#include "ade7758.h"
+
+/**
+ * combine_8_to_32() utility function to munge to u8s into u32
+ **/
+static inline u32 combine_8_to_32(u8 lower, u8 mid, u8 upper)
+{
+ u32 _lower = lower;
+ u32 _mid = mid;
+ u32 _upper = upper;
+
+ return _lower | (_mid << 8) | (_upper << 16);
+}
+
+static IIO_SCAN_EL_C(wform, ADE7758_SCAN_WFORM, ADE7758_WFORM, NULL);
+static IIO_CONST_ATTR_SCAN_EL_TYPE(wform, s, 24, 32);
+static IIO_SCAN_EL_TIMESTAMP(1);
+static IIO_CONST_ATTR_SCAN_EL_TYPE(timestamp, s, 64, 64);
+
+static struct attribute *ade7758_scan_el_attrs[] = {
+ &iio_scan_el_wform.dev_attr.attr,
+ &iio_const_attr_wform_index.dev_attr.attr,
+ &iio_const_attr_wform_type.dev_attr.attr,
+ &iio_scan_el_timestamp.dev_attr.attr,
+ &iio_const_attr_timestamp_index.dev_attr.attr,
+ &iio_const_attr_timestamp_type.dev_attr.attr,
+ NULL,
+};
+
+static struct attribute_group ade7758_scan_el_group = {
+ .attrs = ade7758_scan_el_attrs,
+ .name = "scan_elements",
+};
+
+/**
+ * ade7758_poll_func_th() top half interrupt handler called by trigger
+ * @private_data: iio_dev
+ **/
+static void ade7758_poll_func_th(struct iio_dev *indio_dev, s64 time)
+{
+ struct ade7758_state *st = iio_dev_get_devdata(indio_dev);
+ st->last_timestamp = time;
+ schedule_work(&st->work_trigger_to_ring);
+ /* Indicate that this interrupt is being handled */
+
+ /* Technically this is trigger related, but without this
+ * handler running there is currently no way for the interrupt
+ * to clear.
+ */
+}
+
+/**
+ * ade7758_spi_read_burst() - read all data registers
+ * @dev: device associated with child of actual device (iio_dev or iio_trig)
+ * @rx: somewhere to pass back the value read (min size is 24 bytes)
+ **/
+static int ade7758_spi_read_burst(struct device *dev, u8 *rx)
+{
+ struct spi_message msg;
+ struct iio_dev *indio_dev = dev_get_drvdata(dev);
+ struct ade7758_state *st = iio_dev_get_devdata(indio_dev);
+ int ret;
+
+ struct spi_transfer xfers[] = {
+ {
+ .tx_buf = st->tx,
+ .rx_buf = rx,
+ .bits_per_word = 8,
+ .len = 4,
+ }, {
+ .tx_buf = st->tx + 4,
+ .rx_buf = rx,
+ .bits_per_word = 8,
+ .len = 4,
+ },
+ };
+
+ mutex_lock(&st->buf_lock);
+ st->tx[0] = ADE7758_READ_REG(ADE7758_RSTATUS);
+ st->tx[1] = 0;
+ st->tx[2] = 0;
+ st->tx[3] = 0;
+ st->tx[4] = ADE7758_READ_REG(ADE7758_WFORM);
+ st->tx[5] = 0;
+ st->tx[6] = 0;
+ st->tx[7] = 0;
+
+ spi_message_init(&msg);
+ spi_message_add_tail(&xfers[0], &msg);
+ spi_message_add_tail(&xfers[1], &msg);
+ ret = spi_sync(st->us, &msg);
+ if (ret)
+ dev_err(&st->us->dev, "problem when reading WFORM value\n");
+
+ mutex_unlock(&st->buf_lock);
+
+ return ret;
+}
+
+/* Whilst this makes a lot of calls to iio_sw_ring functions - it is to device
+ * specific to be rolled into the core.
+ */
+static void ade7758_trigger_bh_to_ring(struct work_struct *work_s)
+{
+ struct ade7758_state *st
+ = container_of(work_s, struct ade7758_state,
+ work_trigger_to_ring);
+ struct iio_ring_buffer *ring = st->indio_dev->ring;
+
+ int i = 0;
+ s32 *data;
+ size_t datasize = ring->access.get_bytes_per_datum(ring);
+
+ data = kmalloc(datasize, GFP_KERNEL);
+ if (data == NULL) {
+ dev_err(&st->us->dev, "memory alloc failed in ring bh");
+ return;
+ }
+
+ if (ring->scan_count)
+ if (ade7758_spi_read_burst(&st->indio_dev->dev, st->rx) >= 0)
+ for (; i < ring->scan_count; i++)
+ data[i] = combine_8_to_32(st->rx[i*2+2],
+ st->rx[i*2+1],
+ st->rx[i*2]);
+
+ /* Guaranteed to be aligned with 8 byte boundary */
+ if (ring->scan_timestamp)
+ *((s64 *)
+ (((u32)data + 4 * ring->scan_count + 4) & ~0x7)) =
+ st->last_timestamp;
+
+ ring->access.store_to(ring,
+ (u8 *)data,
+ st->last_timestamp);
+
+ iio_trigger_notify_done(st->indio_dev->trig);
+ kfree(data);
+
+ return;
+}
+
+void ade7758_unconfigure_ring(struct iio_dev *indio_dev)
+{
+ kfree(indio_dev->pollfunc);
+ iio_sw_rb_free(indio_dev->ring);
+}
+
+int ade7758_configure_ring(struct iio_dev *indio_dev)
+{
+ int ret = 0;
+ struct ade7758_state *st = indio_dev->dev_data;
+ struct iio_ring_buffer *ring;
+ INIT_WORK(&st->work_trigger_to_ring, ade7758_trigger_bh_to_ring);
+
+ ring = iio_sw_rb_allocate(indio_dev);
+ if (!ring) {
+ ret = -ENOMEM;
+ return ret;
+ }
+ indio_dev->ring = ring;
+ /* Effectively select the ring buffer implementation */
+ iio_ring_sw_register_funcs(&ring->access);
+ ring->bpe = 4;
+ ring->scan_el_attrs = &ade7758_scan_el_group;
+ ring->scan_timestamp = true;
+ ring->preenable = &iio_sw_ring_preenable;
+ ring->postenable = &iio_triggered_ring_postenable;
+ ring->predisable = &iio_triggered_ring_predisable;
+ ring->owner = THIS_MODULE;
+
+ /* Set default scan mode */
+ iio_scan_mask_set(ring, iio_scan_el_wform.number);
+
+ ret = iio_alloc_pollfunc(indio_dev, NULL, &ade7758_poll_func_th);
+ if (ret)
+ goto error_iio_sw_rb_free;
+
+ indio_dev->modes |= INDIO_RING_TRIGGERED;
+ return 0;
+
+error_iio_sw_rb_free:
+ iio_sw_rb_free(indio_dev->ring);
+ return ret;
+}
+
+int ade7758_initialize_ring(struct iio_ring_buffer *ring)
+{
+ return iio_ring_buffer_register(ring, 0);
+}
+
+void ade7758_uninitialize_ring(struct iio_ring_buffer *ring)
+{
+ iio_ring_buffer_unregister(ring);
+}
projects / mv-sheeva.git / blobdiff