diff options
Diffstat (limited to 'drivers/staging/iio/iio_simple_dummy_buffer.c')
| -rw-r--r-- | drivers/staging/iio/iio_simple_dummy_buffer.c | 192 |
1 files changed, 0 insertions, 192 deletions
diff --git a/drivers/staging/iio/iio_simple_dummy_buffer.c b/drivers/staging/iio/iio_simple_dummy_buffer.c deleted file mode 100644 index cf44a6f79..000000000 --- a/drivers/staging/iio/iio_simple_dummy_buffer.c +++ /dev/null @@ -1,192 +0,0 @@ -/** - * Copyright (c) 2011 Jonathan Cameron - * - * 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. - * - * Buffer handling elements of industrial I/O reference driver. - * Uses the kfifo buffer. - * - * To test without hardware use the sysfs trigger. - */ - -#include <linux/kernel.h> -#include <linux/export.h> -#include <linux/slab.h> -#include <linux/interrupt.h> -#include <linux/irq.h> -#include <linux/bitmap.h> - -#include <linux/iio/iio.h> -#include <linux/iio/trigger_consumer.h> -#include <linux/iio/kfifo_buf.h> - -#include "iio_simple_dummy.h" - -/* Some fake data */ - -static const s16 fakedata[] = { - [DUMMY_INDEX_VOLTAGE_0] = 7, - [DUMMY_INDEX_DIFFVOLTAGE_1M2] = -33, - [DUMMY_INDEX_DIFFVOLTAGE_3M4] = -2, - [DUMMY_INDEX_ACCELX] = 344, -}; - -/** - * iio_simple_dummy_trigger_h() - the trigger handler function - * @irq: the interrupt number - * @p: private data - always a pointer to the poll func. - * - * This is the guts of buffered capture. On a trigger event occurring, - * if the pollfunc is attached then this handler is called as a threaded - * interrupt (and hence may sleep). It is responsible for grabbing data - * from the device and pushing it into the associated buffer. - */ -static irqreturn_t iio_simple_dummy_trigger_h(int irq, void *p) -{ - struct iio_poll_func *pf = p; - struct iio_dev *indio_dev = pf->indio_dev; - int len = 0; - u16 *data; - - data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL); - if (!data) - goto done; - - if (!bitmap_empty(indio_dev->active_scan_mask, indio_dev->masklength)) { - /* - * Three common options here: - * hardware scans: certain combinations of channels make - * up a fast read. The capture will consist of all of them. - * Hence we just call the grab data function and fill the - * buffer without processing. - * software scans: can be considered to be random access - * so efficient reading is just a case of minimal bus - * transactions. - * software culled hardware scans: - * occasionally a driver may process the nearest hardware - * scan to avoid storing elements that are not desired. This - * is the fiddliest option by far. - * Here let's pretend we have random access. And the values are - * in the constant table fakedata. - */ - int i, j; - - for (i = 0, j = 0; - i < bitmap_weight(indio_dev->active_scan_mask, - indio_dev->masklength); - i++, j++) { - j = find_next_bit(indio_dev->active_scan_mask, - indio_dev->masklength, j); - /* random access read from the 'device' */ - data[i] = fakedata[j]; - len += 2; - } - } - - iio_push_to_buffers_with_timestamp(indio_dev, data, iio_get_time_ns()); - - kfree(data); - -done: - /* - * Tell the core we are done with this trigger and ready for the - * next one. - */ - iio_trigger_notify_done(indio_dev->trig); - - return IRQ_HANDLED; -} - -static const struct iio_buffer_setup_ops iio_simple_dummy_buffer_setup_ops = { - /* - * iio_triggered_buffer_postenable: - * Generic function that simply attaches the pollfunc to the trigger. - * Replace this to mess with hardware state before we attach the - * trigger. - */ - .postenable = &iio_triggered_buffer_postenable, - /* - * iio_triggered_buffer_predisable: - * Generic function that simple detaches the pollfunc from the trigger. - * Replace this to put hardware state back again after the trigger is - * detached but before userspace knows we have disabled the ring. - */ - .predisable = &iio_triggered_buffer_predisable, -}; - -int iio_simple_dummy_configure_buffer(struct iio_dev *indio_dev) -{ - int ret; - struct iio_buffer *buffer; - - /* Allocate a buffer to use - here a kfifo */ - buffer = iio_kfifo_allocate(); - if (!buffer) { - ret = -ENOMEM; - goto error_ret; - } - - iio_device_attach_buffer(indio_dev, buffer); - - /* Enable timestamps by default */ - buffer->scan_timestamp = true; - - /* - * Tell the core what device type specific functions should - * be run on either side of buffer capture enable / disable. - */ - indio_dev->setup_ops = &iio_simple_dummy_buffer_setup_ops; - - /* - * Configure a polling function. - * When a trigger event with this polling function connected - * occurs, this function is run. Typically this grabs data - * from the device. - * - * NULL for the bottom half. This is normally implemented only if we - * either want to ping a capture now pin (no sleeping) or grab - * a timestamp as close as possible to a data ready trigger firing. - * - * IRQF_ONESHOT ensures irqs are masked such that only one instance - * of the handler can run at a time. - * - * "iio_simple_dummy_consumer%d" formatting string for the irq 'name' - * as seen under /proc/interrupts. Remaining parameters as per printk. - */ - indio_dev->pollfunc = iio_alloc_pollfunc(NULL, - &iio_simple_dummy_trigger_h, - IRQF_ONESHOT, - indio_dev, - "iio_simple_dummy_consumer%d", - indio_dev->id); - - if (!indio_dev->pollfunc) { - ret = -ENOMEM; - goto error_free_buffer; - } - - /* - * Notify the core that this device is capable of buffered capture - * driven by a trigger. - */ - indio_dev->modes |= INDIO_BUFFER_TRIGGERED; - - return 0; - -error_free_buffer: - iio_kfifo_free(indio_dev->buffer); -error_ret: - return ret; -} - -/** - * iio_simple_dummy_unconfigure_buffer() - release buffer resources - * @indo_dev: device instance state - */ -void iio_simple_dummy_unconfigure_buffer(struct iio_dev *indio_dev) -{ - iio_dealloc_pollfunc(indio_dev->pollfunc); - iio_kfifo_free(indio_dev->buffer); -} |