diff options
Diffstat (limited to 'drivers/staging/iio/accel/adis16240_ring.c')
| -rw-r--r-- | drivers/staging/iio/accel/adis16240_ring.c | 254 |
1 files changed, 254 insertions, 0 deletions
diff --git a/drivers/staging/iio/accel/adis16240_ring.c b/drivers/staging/iio/accel/adis16240_ring.c new file mode 100644 index 000000000000..26b677bd84c0 --- /dev/null +++ b/drivers/staging/iio/accel/adis16240_ring.c @@ -0,0 +1,254 @@ +#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/sysfs.h> +#include <linux/list.h> + +#include "../iio.h" +#include "../sysfs.h" +#include "../ring_sw.h" +#include "accel.h" +#include "../trigger.h" +#include "adis16240.h" + +/** + * combine_8_to_16() utility function to munge to u8s into u16 + **/ +static inline u16 combine_8_to_16(u8 lower, u8 upper) +{ + u16 _lower = lower; + u16 _upper = upper; + return _lower | (_upper << 8); +} + +static IIO_SCAN_EL_C(supply, ADIS16240_SCAN_SUPPLY, IIO_UNSIGNED(10), + ADIS16240_SUPPLY_OUT, NULL); +static IIO_SCAN_EL_C(accel_x, ADIS16240_SCAN_ACC_X, IIO_SIGNED(10), + ADIS16240_XACCL_OUT, NULL); +static IIO_SCAN_EL_C(accel_y, ADIS16240_SCAN_ACC_Y, IIO_SIGNED(10), + ADIS16240_YACCL_OUT, NULL); +static IIO_SCAN_EL_C(accel_z, ADIS16240_SCAN_ACC_Z, IIO_SIGNED(10), + ADIS16240_ZACCL_OUT, NULL); +static IIO_SCAN_EL_C(aux_adc, ADIS16240_SCAN_AUX_ADC, IIO_UNSIGNED(10), + ADIS16240_AUX_ADC, NULL); +static IIO_SCAN_EL_C(temp, ADIS16240_SCAN_TEMP, IIO_UNSIGNED(10), + ADIS16240_TEMP_OUT, NULL); + +static IIO_SCAN_EL_TIMESTAMP(6); + +static struct attribute *adis16240_scan_el_attrs[] = { + &iio_scan_el_supply.dev_attr.attr, + &iio_scan_el_accel_x.dev_attr.attr, + &iio_scan_el_accel_y.dev_attr.attr, + &iio_scan_el_accel_z.dev_attr.attr, + &iio_scan_el_aux_adc.dev_attr.attr, + &iio_scan_el_temp.dev_attr.attr, + &iio_scan_el_timestamp.dev_attr.attr, + NULL, +}; + +static struct attribute_group adis16240_scan_el_group = { + .attrs = adis16240_scan_el_attrs, + .name = "scan_elements", +}; + +/** + * adis16240_poll_func_th() top half interrupt handler called by trigger + * @private_data: iio_dev + **/ +static void adis16240_poll_func_th(struct iio_dev *indio_dev) +{ + struct adis16240_state *st = iio_dev_get_devdata(indio_dev); + st->last_timestamp = indio_dev->trig->timestamp; + schedule_work(&st->work_trigger_to_ring); +} + +/** + * adis16240_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 adis16240_read_ring_data(struct device *dev, u8 *rx) +{ + struct spi_message msg; + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct adis16240_state *st = iio_dev_get_devdata(indio_dev); + struct spi_transfer xfers[ADIS16240_OUTPUTS + 1]; + int ret; + int i; + + mutex_lock(&st->buf_lock); + + spi_message_init(&msg); + + memset(xfers, 0, sizeof(xfers)); + for (i = 0; i <= ADIS16240_OUTPUTS; i++) { + xfers[i].bits_per_word = 8; + xfers[i].cs_change = 1; + xfers[i].len = 2; + xfers[i].delay_usecs = 30; + xfers[i].tx_buf = st->tx + 2 * i; + st->tx[2 * i] + = ADIS16240_READ_REG(ADIS16240_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; +} + + +static void adis16240_trigger_bh_to_ring(struct work_struct *work_s) +{ + struct adis16240_state *st + = container_of(work_s, struct adis16240_state, + work_trigger_to_ring); + + int i = 0; + s16 *data; + size_t datasize = st->indio_dev + ->ring->access.get_bpd(st->indio_dev->ring); + + data = kmalloc(datasize , GFP_KERNEL); + if (data == NULL) { + dev_err(&st->us->dev, "memory alloc failed in ring bh"); + return; + } + + if (st->indio_dev->scan_count) + if (adis16240_read_ring_data(&st->indio_dev->dev, st->rx) >= 0) + for (; i < st->indio_dev->scan_count; i++) { + data[i] = combine_8_to_16(st->rx[i*2+1], + st->rx[i*2]); + } + + /* Guaranteed to be aligned with 8 byte boundary */ + if (st->indio_dev->scan_timestamp) + *((s64 *)(data + ((i + 3)/4)*4)) = st->last_timestamp; + + st->indio_dev->ring->access.store_to(st->indio_dev->ring, + (u8 *)data, + st->last_timestamp); + + iio_trigger_notify_done(st->indio_dev->trig); + kfree(data); + + return; +} + +static int adis16240_data_rdy_ring_preenable(struct iio_dev *indio_dev) +{ + size_t size; + dev_dbg(&indio_dev->dev, "%s\n", __func__); + /* Check if there are any scan elements enabled, if not fail*/ + if (!(indio_dev->scan_count || indio_dev->scan_timestamp)) + return -EINVAL; + + if (indio_dev->ring->access.set_bpd) { + if (indio_dev->scan_timestamp) + if (indio_dev->scan_count) + /* Timestamp (aligned sizeof(s64) and data */ + size = (((indio_dev->scan_count * sizeof(s16)) + + sizeof(s64) - 1) + & ~(sizeof(s64) - 1)) + + sizeof(s64); + else /* Timestamp only */ + size = sizeof(s64); + else /* Data only */ + size = indio_dev->scan_count*sizeof(s16); + indio_dev->ring->access.set_bpd(indio_dev->ring, size); + } + + return 0; +} + +static int adis16240_data_rdy_ring_postenable(struct iio_dev *indio_dev) +{ + return indio_dev->trig + ? iio_trigger_attach_poll_func(indio_dev->trig, + indio_dev->pollfunc) + : 0; +} + +static int adis16240_data_rdy_ring_predisable(struct iio_dev *indio_dev) +{ + return indio_dev->trig + ? iio_trigger_dettach_poll_func(indio_dev->trig, + indio_dev->pollfunc) + : 0; +} + +void adis16240_unconfigure_ring(struct iio_dev *indio_dev) +{ + kfree(indio_dev->pollfunc); + iio_sw_rb_free(indio_dev->ring); +} + +int adis16240_configure_ring(struct iio_dev *indio_dev) +{ + int ret = 0; + struct adis16240_state *st = indio_dev->dev_data; + struct iio_ring_buffer *ring; + INIT_WORK(&st->work_trigger_to_ring, adis16240_trigger_bh_to_ring); + /* Set default scan mode */ + + iio_scan_mask_set(indio_dev, iio_scan_el_supply.number); + iio_scan_mask_set(indio_dev, iio_scan_el_accel_x.number); + iio_scan_mask_set(indio_dev, iio_scan_el_accel_y.number); + iio_scan_mask_set(indio_dev, iio_scan_el_accel_z.number); + iio_scan_mask_set(indio_dev, iio_scan_el_temp.number); + iio_scan_mask_set(indio_dev, iio_scan_el_aux_adc.number); + indio_dev->scan_timestamp = true; + + indio_dev->scan_el_attrs = &adis16240_scan_el_group; + + 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->preenable = &adis16240_data_rdy_ring_preenable; + ring->postenable = &adis16240_data_rdy_ring_postenable; + ring->predisable = &adis16240_data_rdy_ring_predisable; + ring->owner = THIS_MODULE; + + indio_dev->pollfunc = kzalloc(sizeof(*indio_dev->pollfunc), GFP_KERNEL); + if (indio_dev->pollfunc == NULL) { + ret = -ENOMEM; + goto error_iio_sw_rb_free;; + } + indio_dev->pollfunc->poll_func_main = &adis16240_poll_func_th; + indio_dev->pollfunc->private_data = indio_dev; + indio_dev->modes |= INDIO_RING_TRIGGERED; + return 0; + +error_iio_sw_rb_free: + iio_sw_rb_free(indio_dev->ring); + return ret; +} + +int adis16240_initialize_ring(struct iio_ring_buffer *ring) +{ + return iio_ring_buffer_register(ring, 0); +} + +void adis16240_uninitialize_ring(struct iio_ring_buffer *ring) +{ + iio_ring_buffer_unregister(ring); +} |