diff options
Diffstat (limited to 'drivers/staging/iio/meter/ade7758_ring.c')
| -rw-r--r-- | drivers/staging/iio/meter/ade7758_ring.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/staging/iio/meter/ade7758_ring.c b/drivers/staging/iio/meter/ade7758_ring.c new file mode 100644 index 000000000..9a24e0226 --- /dev/null +++ b/drivers/staging/iio/meter/ade7758_ring.c @@ -0,0 +1,180 @@ +/* + * ADE7758 Poly Phase Multifunction Energy Metering IC driver + * + * Copyright 2010-2011 Analog Devices Inc. + * + * Licensed under the GPL-2. + */ +#include <linux/export.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/spi/spi.h> +#include <linux/slab.h> +#include <asm/unaligned.h> + +#include <linux/iio/iio.h> +#include <linux/iio/kfifo_buf.h> +#include <linux/iio/trigger_consumer.h> +#include "ade7758.h" + +/** + * ade7758_spi_read_burst() - read data registers + * @indio_dev: the IIO device + **/ +static int ade7758_spi_read_burst(struct iio_dev *indio_dev) +{ + struct ade7758_state *st = iio_priv(indio_dev); + int ret; + + ret = spi_sync(st->us, &st->ring_msg); + if (ret) + dev_err(&st->us->dev, "problem when reading WFORM value\n"); + + return ret; +} + +static int ade7758_write_waveform_type(struct device *dev, unsigned type) +{ + int ret; + u8 reg; + + ret = ade7758_spi_read_reg_8(dev, + ADE7758_WAVMODE, + ®); + if (ret) + goto out; + + reg &= ~0x1F; + reg |= type & 0x1F; + + ret = ade7758_spi_write_reg_8(dev, + ADE7758_WAVMODE, + reg); +out: + return ret; +} + +/* Whilst this makes a lot of calls to iio_sw_ring functions - it is too device + * specific to be rolled into the core. + */ +static irqreturn_t ade7758_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct ade7758_state *st = iio_priv(indio_dev); + s64 dat64[2]; + u32 *dat32 = (u32 *)dat64; + + if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength)) + if (ade7758_spi_read_burst(indio_dev) >= 0) + *dat32 = get_unaligned_be32(&st->rx_buf[5]) & 0xFFFFFF; + + iio_push_to_buffers_with_timestamp(indio_dev, dat64, pf->timestamp); + + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +/** + * ade7758_ring_preenable() setup the parameters of the ring before enabling + * + * The complex nature of the setting of the number of bytes per datum is due + * to this driver currently ensuring that the timestamp is stored at an 8 + * byte boundary. + **/ +static int ade7758_ring_preenable(struct iio_dev *indio_dev) +{ + unsigned channel; + + if (bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength)) + return -EINVAL; + + channel = find_first_bit(indio_dev->active_scan_mask, + indio_dev->masklength); + + ade7758_write_waveform_type(&indio_dev->dev, + indio_dev->channels[channel].address); + + return 0; +} + +static const struct iio_buffer_setup_ops ade7758_ring_setup_ops = { + .preenable = &ade7758_ring_preenable, + .postenable = &iio_triggered_buffer_postenable, + .predisable = &iio_triggered_buffer_predisable, + .validate_scan_mask = &iio_validate_scan_mask_onehot, +}; + +void ade7758_unconfigure_ring(struct iio_dev *indio_dev) +{ + iio_dealloc_pollfunc(indio_dev->pollfunc); + iio_kfifo_free(indio_dev->buffer); +} + +int ade7758_configure_ring(struct iio_dev *indio_dev) +{ + struct ade7758_state *st = iio_priv(indio_dev); + struct iio_buffer *buffer; + int ret = 0; + + buffer = iio_kfifo_allocate(); + if (!buffer) + return -ENOMEM; + + iio_device_attach_buffer(indio_dev, buffer); + + indio_dev->setup_ops = &ade7758_ring_setup_ops; + + indio_dev->pollfunc = iio_alloc_pollfunc(&iio_pollfunc_store_time, + &ade7758_trigger_handler, + 0, + indio_dev, + "ade7759_consumer%d", + indio_dev->id); + if (!indio_dev->pollfunc) { + ret = -ENOMEM; + goto error_iio_kfifo_free; + } + + indio_dev->modes |= INDIO_BUFFER_TRIGGERED; + + st->tx_buf[0] = ADE7758_READ_REG(ADE7758_RSTATUS); + st->tx_buf[1] = 0; + st->tx_buf[2] = 0; + st->tx_buf[3] = 0; + st->tx_buf[4] = ADE7758_READ_REG(ADE7758_WFORM); + st->tx_buf[5] = 0; + st->tx_buf[6] = 0; + st->tx_buf[7] = 0; + + /* build spi ring message */ + st->ring_xfer[0].tx_buf = &st->tx_buf[0]; + st->ring_xfer[0].len = 1; + st->ring_xfer[0].bits_per_word = 8; + st->ring_xfer[0].delay_usecs = 4; + st->ring_xfer[1].rx_buf = &st->rx_buf[1]; + st->ring_xfer[1].len = 3; + st->ring_xfer[1].bits_per_word = 8; + st->ring_xfer[1].cs_change = 1; + + st->ring_xfer[2].tx_buf = &st->tx_buf[4]; + st->ring_xfer[2].len = 1; + st->ring_xfer[2].bits_per_word = 8; + st->ring_xfer[2].delay_usecs = 1; + st->ring_xfer[3].rx_buf = &st->rx_buf[5]; + st->ring_xfer[3].len = 3; + st->ring_xfer[3].bits_per_word = 8; + + spi_message_init(&st->ring_msg); + spi_message_add_tail(&st->ring_xfer[0], &st->ring_msg); + spi_message_add_tail(&st->ring_xfer[1], &st->ring_msg); + spi_message_add_tail(&st->ring_xfer[2], &st->ring_msg); + spi_message_add_tail(&st->ring_xfer[3], &st->ring_msg); + + return 0; + +error_iio_kfifo_free: + iio_kfifo_free(indio_dev->buffer); + return ret; +} |