diff options
Diffstat (limited to 'drivers/staging/iio/accel/adis16204_ring.c')
-rw-r--r-- | drivers/staging/iio/accel/adis16204_ring.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/drivers/staging/iio/accel/adis16204_ring.c b/drivers/staging/iio/accel/adis16204_ring.c new file mode 100644 index 00000000000..420b160fe3a --- /dev/null +++ b/drivers/staging/iio/accel/adis16204_ring.c @@ -0,0 +1,206 @@ +#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.h" +#include "../trigger.h" +#include "adis16204.h" + +static IIO_SCAN_EL_C(in_supply, ADIS16204_SCAN_SUPPLY, ADIS16204_SUPPLY_OUT, NULL); +static IIO_CONST_ATTR_SCAN_EL_TYPE(in_supply, u, 12, 16); +static IIO_SCAN_EL_C(accel_x, ADIS16204_SCAN_ACC_X, ADIS16204_XACCL_OUT, NULL); +static IIO_SCAN_EL_C(accel_y, ADIS16204_SCAN_ACC_Y, ADIS16204_YACCL_OUT, NULL); +static IIO_CONST_ATTR_SCAN_EL_TYPE(accel, s, 14, 16); +static IIO_SCAN_EL_C(in0, ADIS16204_SCAN_AUX_ADC, ADIS16204_AUX_ADC, NULL); +static IIO_CONST_ATTR_SCAN_EL_TYPE(in0, u, 12, 16); +static IIO_SCAN_EL_C(temp, ADIS16204_SCAN_TEMP, ADIS16204_TEMP_OUT, NULL); +static IIO_CONST_ATTR_SCAN_EL_TYPE(temp, u, 12, 16); +static IIO_SCAN_EL_TIMESTAMP(5); +static IIO_CONST_ATTR_SCAN_EL_TYPE(timestamp, s, 64, 64); + +static struct attribute *adis16204_scan_el_attrs[] = { + &iio_scan_el_in_supply.dev_attr.attr, + &iio_const_attr_in_supply_index.dev_attr.attr, + &iio_const_attr_in_supply_type.dev_attr.attr, + &iio_scan_el_accel_x.dev_attr.attr, + &iio_const_attr_accel_x_index.dev_attr.attr, + &iio_scan_el_accel_y.dev_attr.attr, + &iio_const_attr_accel_y_index.dev_attr.attr, + &iio_const_attr_accel_type.dev_attr.attr, + &iio_scan_el_in0.dev_attr.attr, + &iio_const_attr_in0_index.dev_attr.attr, + &iio_const_attr_in0_type.dev_attr.attr, + &iio_scan_el_temp.dev_attr.attr, + &iio_const_attr_temp_index.dev_attr.attr, + &iio_const_attr_temp_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 adis16204_scan_el_group = { + .attrs = adis16204_scan_el_attrs, + .name = "scan_elements", +}; + +/** + * adis16204_poll_func_th() top half interrupt handler called by trigger + * @private_data: iio_dev + **/ +static void adis16204_poll_func_th(struct iio_dev *indio_dev, s64 timestamp) +{ + struct adis16204_state *st = iio_dev_get_devdata(indio_dev); + st->last_timestamp = timestamp; + schedule_work(&st->work_trigger_to_ring); +} + +/** + * adis16204_read_ring_data() read data registers which will be placed into ring + * @dev: device associated with child of actual device (iio_dev or iio_trig) + * @rx: somewhere to pass back the value read + **/ +static int adis16204_read_ring_data(struct device *dev, u8 *rx) +{ + struct spi_message msg; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct adis16204_state *st = iio_dev_get_devdata(indio_dev); + struct spi_transfer xfers[ADIS16204_OUTPUTS + 1]; + int ret; + int i; + + mutex_lock(&st->buf_lock); + + spi_message_init(&msg); + + memset(xfers, 0, sizeof(xfers)); + for (i = 0; i <= ADIS16204_OUTPUTS; i++) { + xfers[i].bits_per_word = 8; + xfers[i].cs_change = 1; + xfers[i].len = 2; + xfers[i].delay_usecs = 20; + xfers[i].tx_buf = st->tx + 2 * i; + st->tx[2 * i] = ADIS16204_READ_REG(ADIS16204_SUPPLY_OUT + 2 * i); + st->tx[2 * i + 1] = 0; + if (i >= 1) + xfers[i].rx_buf = rx + 2 * (i - 1); + spi_message_add_tail(&xfers[i], &msg); + } + + ret = spi_sync(st->us, &msg); + if (ret) + dev_err(&st->us->dev, "problem when burst reading"); + + 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 adis16204_trigger_bh_to_ring(struct work_struct *work_s) +{ + struct adis16204_state *st + = container_of(work_s, struct adis16204_state, + work_trigger_to_ring); + struct iio_ring_buffer *ring = st->indio_dev->ring; + + int i = 0; + s16 *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 (adis16204_read_ring_data(&st->indio_dev->dev, st->rx) >= 0) + for (; i < ring->scan_count; i++) + data[i] = be16_to_cpup( + (__be16 *)&(st->rx[i*2])); + + /* Guaranteed to be aligned with 8 byte boundary */ + if (ring->scan_timestamp) + *((s64 *)(data + ((i + 3)/4)*4)) = 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 adis16204_unconfigure_ring(struct iio_dev *indio_dev) +{ + kfree(indio_dev->pollfunc); + iio_sw_rb_free(indio_dev->ring); +} + +int adis16204_configure_ring(struct iio_dev *indio_dev) +{ + int ret = 0; + struct adis16204_state *st = indio_dev->dev_data; + struct iio_ring_buffer *ring; + INIT_WORK(&st->work_trigger_to_ring, adis16204_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 = 2; + ring->scan_el_attrs = &adis16204_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_in_supply.number); + iio_scan_mask_set(ring, iio_scan_el_accel_x.number); + iio_scan_mask_set(ring, iio_scan_el_accel_y.number); + iio_scan_mask_set(ring, iio_scan_el_temp.number); + iio_scan_mask_set(ring, iio_scan_el_in0.number); + + ret = iio_alloc_pollfunc(indio_dev, NULL, &adis16204_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 adis16204_initialize_ring(struct iio_ring_buffer *ring) +{ + return iio_ring_buffer_register(ring, 0); +} + +void adis16204_uninitialize_ring(struct iio_ring_buffer *ring) +{ + iio_ring_buffer_unregister(ring); +} |