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path: root/drivers/staging/iio/accel/sca3000_ring.c
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Diffstat (limited to 'drivers/staging/iio/accel/sca3000_ring.c')
-rw-r--r--drivers/staging/iio/accel/sca3000_ring.c350
1 files changed, 0 insertions, 350 deletions
diff --git a/drivers/staging/iio/accel/sca3000_ring.c b/drivers/staging/iio/accel/sca3000_ring.c
deleted file mode 100644
index d1cb9b9cf22b..000000000000
--- a/drivers/staging/iio/accel/sca3000_ring.c
+++ /dev/null
@@ -1,350 +0,0 @@
-/*
- * sca3000_ring.c -- support VTI sca3000 series accelerometers via SPI
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- *
- * Copyright (c) 2009 Jonathan Cameron <jic23@kernel.org>
- *
- */
-
-#include <linux/interrupt.h>
-#include <linux/fs.h>
-#include <linux/slab.h>
-#include <linux/kernel.h>
-#include <linux/spi/spi.h>
-#include <linux/sysfs.h>
-#include <linux/sched.h>
-#include <linux/poll.h>
-
-#include <linux/iio/iio.h>
-#include <linux/iio/sysfs.h>
-#include <linux/iio/buffer.h>
-#include "../ring_hw.h"
-#include "sca3000.h"
-
-/* RFC / future work
- *
- * The internal ring buffer doesn't actually change what it holds depending
- * on which signals are enabled etc, merely whether you can read them.
- * As such the scan mode selection is somewhat different than for a software
- * ring buffer and changing it actually covers any data already in the buffer.
- * Currently scan elements aren't configured so it doesn't matter.
- */
-
-static int sca3000_read_data(struct sca3000_state *st,
- u8 reg_address_high,
- u8 **rx_p,
- int len)
-{
- int ret;
- struct spi_transfer xfer[2] = {
- {
- .len = 1,
- .tx_buf = st->tx,
- }, {
- .len = len,
- }
- };
- *rx_p = kmalloc(len, GFP_KERNEL);
- if (!*rx_p) {
- ret = -ENOMEM;
- goto error_ret;
- }
- xfer[1].rx_buf = *rx_p;
- st->tx[0] = SCA3000_READ_REG(reg_address_high);
- ret = spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer));
- if (ret) {
- dev_err(get_device(&st->us->dev), "problem reading register");
- goto error_free_rx;
- }
-
- return 0;
-error_free_rx:
- kfree(*rx_p);
-error_ret:
- return ret;
-}
-
-/**
- * sca3000_read_first_n_hw_rb() - main ring access, pulls data from ring
- * @r: the ring
- * @count: number of samples to try and pull
- * @data: output the actual samples pulled from the hw ring
- *
- * Currently does not provide timestamps. As the hardware doesn't add them they
- * can only be inferred approximately from ring buffer events such as 50% full
- * and knowledge of when buffer was last emptied. This is left to userspace.
- **/
-static int sca3000_read_first_n_hw_rb(struct iio_buffer *r,
- size_t count, char __user *buf)
-{
- struct iio_hw_buffer *hw_ring = iio_to_hw_buf(r);
- struct iio_dev *indio_dev = hw_ring->private;
- struct sca3000_state *st = iio_priv(indio_dev);
- u8 *rx;
- int ret, i, num_available, num_read = 0;
- int bytes_per_sample = 1;
-
- if (st->bpse == 11)
- bytes_per_sample = 2;
-
- mutex_lock(&st->lock);
- if (count % bytes_per_sample) {
- ret = -EINVAL;
- goto error_ret;
- }
-
- ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_BUF_COUNT, 1);
- if (ret)
- goto error_ret;
- num_available = st->rx[0];
- /*
- * num_available is the total number of samples available
- * i.e. number of time points * number of channels.
- */
- if (count > num_available * bytes_per_sample)
- num_read = num_available * bytes_per_sample;
- else
- num_read = count;
-
- ret = sca3000_read_data(st,
- SCA3000_REG_ADDR_RING_OUT,
- &rx, num_read);
- if (ret)
- goto error_ret;
-
- for (i = 0; i < num_read / sizeof(u16); i++)
- *(((u16 *)rx) + i) = be16_to_cpup((__be16 *)rx + i);
-
- if (copy_to_user(buf, rx, num_read))
- ret = -EFAULT;
- kfree(rx);
- r->stufftoread = 0;
-error_ret:
- mutex_unlock(&st->lock);
-
- return ret ? ret : num_read;
-}
-
-static size_t sca3000_ring_buf_data_available(struct iio_buffer *r)
-{
- return r->stufftoread ? r->watermark : 0;
-}
-
-/**
- * sca3000_query_ring_int() is the hardware ring status interrupt enabled
- **/
-static ssize_t sca3000_query_ring_int(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
- int ret, val;
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct sca3000_state *st = iio_priv(indio_dev);
-
- mutex_lock(&st->lock);
- ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);
- val = st->rx[0];
- mutex_unlock(&st->lock);
- if (ret)
- return ret;
-
- return sprintf(buf, "%d\n", !!(val & this_attr->address));
-}
-
-/**
- * sca3000_set_ring_int() set state of ring status interrupt
- **/
-static ssize_t sca3000_set_ring_int(struct device *dev,
- struct device_attribute *attr,
- const char *buf,
- size_t len)
-{
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct sca3000_state *st = iio_priv(indio_dev);
- struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
- u8 val;
- int ret;
-
- mutex_lock(&st->lock);
- ret = kstrtou8(buf, 10, &val);
- if (ret)
- goto error_ret;
- ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_INT_MASK, 1);
- if (ret)
- goto error_ret;
- if (val)
- ret = sca3000_write_reg(st,
- SCA3000_REG_ADDR_INT_MASK,
- st->rx[0] | this_attr->address);
- else
- ret = sca3000_write_reg(st,
- SCA3000_REG_ADDR_INT_MASK,
- st->rx[0] & ~this_attr->address);
-error_ret:
- mutex_unlock(&st->lock);
-
- return ret ? ret : len;
-}
-
-static IIO_DEVICE_ATTR(50_percent, S_IRUGO | S_IWUSR,
- sca3000_query_ring_int,
- sca3000_set_ring_int,
- SCA3000_INT_MASK_RING_HALF);
-
-static IIO_DEVICE_ATTR(75_percent, S_IRUGO | S_IWUSR,
- sca3000_query_ring_int,
- sca3000_set_ring_int,
- SCA3000_INT_MASK_RING_THREE_QUARTER);
-
-static ssize_t sca3000_show_buffer_scale(struct device *dev,
- struct device_attribute *attr,
- char *buf)
-{
- struct iio_dev *indio_dev = dev_to_iio_dev(dev);
- struct sca3000_state *st = iio_priv(indio_dev);
-
- return sprintf(buf, "0.%06d\n", 4 * st->info->scale);
-}
-
-static IIO_DEVICE_ATTR(in_accel_scale,
- S_IRUGO,
- sca3000_show_buffer_scale,
- NULL,
- 0);
-
-/*
- * Ring buffer attributes
- * This device is a bit unusual in that the sampling frequency and bpse
- * only apply to the ring buffer. At all times full rate and accuracy
- * is available via direct reading from registers.
- */
-static const struct attribute *sca3000_ring_attributes[] = {
- &iio_dev_attr_50_percent.dev_attr.attr,
- &iio_dev_attr_75_percent.dev_attr.attr,
- &iio_dev_attr_in_accel_scale.dev_attr.attr,
- NULL,
-};
-
-static struct iio_buffer *sca3000_rb_allocate(struct iio_dev *indio_dev)
-{
- struct iio_buffer *buf;
- struct iio_hw_buffer *ring;
-
- ring = kzalloc(sizeof(*ring), GFP_KERNEL);
- if (!ring)
- return NULL;
-
- ring->private = indio_dev;
- buf = &ring->buf;
- buf->stufftoread = 0;
- buf->length = 64;
- buf->attrs = sca3000_ring_attributes;
- iio_buffer_init(buf);
-
- return buf;
-}
-
-static void sca3000_ring_release(struct iio_buffer *r)
-{
- kfree(iio_to_hw_buf(r));
-}
-
-static const struct iio_buffer_access_funcs sca3000_ring_access_funcs = {
- .read_first_n = &sca3000_read_first_n_hw_rb,
- .data_available = sca3000_ring_buf_data_available,
- .release = sca3000_ring_release,
-
- .modes = INDIO_BUFFER_HARDWARE,
-};
-
-int sca3000_configure_ring(struct iio_dev *indio_dev)
-{
- struct iio_buffer *buffer;
-
- buffer = sca3000_rb_allocate(indio_dev);
- if (!buffer)
- return -ENOMEM;
- indio_dev->modes |= INDIO_BUFFER_HARDWARE;
-
- indio_dev->buffer->access = &sca3000_ring_access_funcs;
-
- iio_device_attach_buffer(indio_dev, buffer);
-
- return 0;
-}
-
-void sca3000_unconfigure_ring(struct iio_dev *indio_dev)
-{
- iio_buffer_put(indio_dev->buffer);
-}
-
-static inline
-int __sca3000_hw_ring_state_set(struct iio_dev *indio_dev, bool state)
-{
- struct sca3000_state *st = iio_priv(indio_dev);
- int ret;
-
- mutex_lock(&st->lock);
- ret = sca3000_read_data_short(st, SCA3000_REG_ADDR_MODE, 1);
- if (ret)
- goto error_ret;
- if (state) {
- dev_info(&indio_dev->dev, "supposedly enabling ring buffer\n");
- ret = sca3000_write_reg(st,
- SCA3000_REG_ADDR_MODE,
- (st->rx[0] | SCA3000_RING_BUF_ENABLE));
- } else
- ret = sca3000_write_reg(st,
- SCA3000_REG_ADDR_MODE,
- (st->rx[0] & ~SCA3000_RING_BUF_ENABLE));
-error_ret:
- mutex_unlock(&st->lock);
-
- return ret;
-}
-
-/**
- * sca3000_hw_ring_preenable() hw ring buffer preenable function
- *
- * Very simple enable function as the chip will allows normal reads
- * during ring buffer operation so as long as it is indeed running
- * before we notify the core, the precise ordering does not matter.
- **/
-static int sca3000_hw_ring_preenable(struct iio_dev *indio_dev)
-{
- return __sca3000_hw_ring_state_set(indio_dev, 1);
-}
-
-static int sca3000_hw_ring_postdisable(struct iio_dev *indio_dev)
-{
- return __sca3000_hw_ring_state_set(indio_dev, 0);
-}
-
-static const struct iio_buffer_setup_ops sca3000_ring_setup_ops = {
- .preenable = &sca3000_hw_ring_preenable,
- .postdisable = &sca3000_hw_ring_postdisable,
-};
-
-void sca3000_register_ring_funcs(struct iio_dev *indio_dev)
-{
- indio_dev->setup_ops = &sca3000_ring_setup_ops;
-}
-
-/**
- * sca3000_ring_int_process() ring specific interrupt handling.
- *
- * This is only split from the main interrupt handler so as to
- * reduce the amount of code if the ring buffer is not enabled.
- **/
-void sca3000_ring_int_process(u8 val, struct iio_buffer *ring)
-{
- if (val & (SCA3000_INT_STATUS_THREE_QUARTERS |
- SCA3000_INT_STATUS_HALF)) {
- ring->stufftoread = true;
- wake_up_interruptible(&ring->pollq);
- }
-}
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