1 files changed, 411 insertions, 0 deletions
diff --git a/drivers/staging/iio/iio.h b/drivers/staging/iio/iio.h
new file mode 100644
index 000000000000..25ccb809221e
--- /dev/null
+++ b/drivers/staging/iio/iio.h
@@ -0,0 +1,411 @@
+/* The industrial I/O core
+ *
+ * Copyright (c) 2008 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.
+ */
+
+#ifndef _INDUSTRIAL_IO_H_
+#define _INDUSTRIAL_IO_H_
+
+#include <linux/device.h>
+#include <linux/cdev.h>
+#include "sysfs.h"
+#include "chrdev.h"
+
+/* IIO TODO LIST */
+/* Static device specific elements (conversion factors etc)
+ * should be exported via sysfs
+ *
+ * Provide means of adjusting timer accuracy.
+ * Currently assumes nano seconds.
+ */
+
+/* Event interface flags */
+#define IIO_BUSY_BIT_POS 1
+
+struct iio_dev;
+
+/**
+ * iio_get_time_ns() - utility function to get a time stamp for events etc
+ **/
+static inline s64 iio_get_time_ns(void)
+{
+	struct timespec ts;
+	/*
+	 * calls getnstimeofday.
+	 * If hrtimers then up to ns accurate, if not microsecond.
+	 */
+	ktime_get_real_ts(&ts);
+
+	return timespec_to_ns(&ts);
+}
+
+/**
+ * iio_add_event_to_list() - Wraps adding to event lists
+ * @el:		the list element of the event to be handled.
+ * @head:	the list associated with the event handler being used.
+ *
+ * Does reference counting to allow shared handlers.
+ **/
+void iio_add_event_to_list(struct iio_event_handler_list *el,
+			   struct list_head *head);
+
+/**
+ * iio_remove_event_from_list() - Wraps removing from event list
+ * @el:		element to be removed
+ * @head:	associate list head for the interrupt handler.
+ *
+ * Does reference counting to allow shared handlers.
+ **/
+void iio_remove_event_from_list(struct iio_event_handler_list *el,
+				struct list_head *head);
+
+/* Device operating modes */
+#define INDIO_DIRECT_MODE		0x01
+#define INDIO_RING_TRIGGERED		0x02
+#define INDIO_RING_HARDWARE_BUFFER	0x08
+
+#define INDIO_ALL_RING_MODES (INDIO_RING_TRIGGERED | INDIO_RING_HARDWARE_BUFFER)
+
+/* Vast majority of this is set by the industrialio subsystem on a
+ * call to iio_device_register. */
+
+/**
+ * struct iio_dev - industrial I/O device
+ * @id:			[INTERN] used to identify device internally
+ * @dev_data:		[DRIVER] device specific data
+ * @modes:		[DRIVER] operating modes supported by device
+ * @currentmode:	[DRIVER] current operating mode
+ * @dev:		[DRIVER] device structure, should be assigned a parent
+ *			and owner
+ * @attrs:		[DRIVER] general purpose device attributes
+ * @driver_module:	[DRIVER] module structure used to ensure correct
+ *			ownership of chrdevs etc
+ * @num_interrupt_lines:[DRIVER] number of physical interrupt lines from device
+ * @interrupts:		[INTERN] interrupt line specific event lists etc
+ * @event_attrs:	[DRIVER] event control attributes
+ * @event_conf_attrs:	[DRIVER] event configuration attributes
+ * @event_interfaces:	[INTERN] event chrdevs associated with interrupt lines
+ * @ring:		[DRIVER] any ring buffer present
+ * @mlock:		[INTERN] lock used to prevent simultaneous device state
+ *			changes
+ * @scan_el_attrs:	[DRIVER] control of scan elements if that scan mode
+ *			control method is used
+ * @scan_count:	[INTERN] the number of elements in the current scan mode
+ * @scan_mask:		[INTERN] bitmask used in masking scan mode elements
+ * @scan_timestamp:	[INTERN] does the scan mode include a timestamp
+ * @trig:		[INTERN] current device trigger (ring buffer modes)
+ * @pollfunc:		[DRIVER] function run on trigger being recieved
+ **/
+struct iio_dev {
+	int				id;
+	void				*dev_data;
+	int				modes;
+	int				currentmode;
+	struct device			dev;
+	const struct attribute_group	*attrs;
+	struct module			*driver_module;
+
+	int				num_interrupt_lines;
+	struct iio_interrupt		**interrupts;
+	struct attribute_group		*event_attrs;
+	struct attribute_group		*event_conf_attrs;
+
+	struct iio_event_interface	*event_interfaces;
+
+	struct iio_ring_buffer		*ring;
+	struct mutex			mlock;
+
+	struct attribute_group		*scan_el_attrs;
+	int				scan_count;
+
+	u16				scan_mask;
+	bool				scan_timestamp;
+	struct iio_trigger		*trig;
+	struct iio_poll_func		*pollfunc;
+};
+
+/*
+ * These are mainly provided to allow for a change of implementation if a device
+ * has a large number of scan elements
+ */
+#define IIO_MAX_SCAN_LENGTH 15
+
+static inline int iio_scan_mask_query(struct iio_dev *dev_info, int bit)
+{
+	if (bit > IIO_MAX_SCAN_LENGTH)
+		return -EINVAL;
+	else
+		return !!(dev_info->scan_mask & (1 << bit));
+};
+
+static inline int iio_scan_mask_set(struct iio_dev *dev_info, int bit)
+{
+	if (bit > IIO_MAX_SCAN_LENGTH)
+		return -EINVAL;
+	dev_info->scan_mask |= (1 << bit);
+	dev_info->scan_count++;
+	return 0;
+};
+
+static inline int iio_scan_mask_clear(struct iio_dev *dev_info, int bit)
+{
+	if (bit > IIO_MAX_SCAN_LENGTH)
+		return -EINVAL;
+	dev_info->scan_mask &= ~(1 << bit);
+	dev_info->scan_count--;
+	return 0;
+};
+
+/**
+ * iio_scan_mask_count_to_right() - how many scan elements occur before here
+ * @dev_info: the iio_device whose scan mode we are querying
+ * @bit: which number scan element is this
+ **/
+static inline int iio_scan_mask_count_to_right(struct iio_dev *dev_info,
+int bit)
+{
+	int count = 0;
+	int mask = (1 << bit);
+	if (bit > IIO_MAX_SCAN_LENGTH)
+		return -EINVAL;
+	while (mask) {
+		mask >>= 1;
+		if (mask & dev_info->scan_mask)
+			count++;
+	}
+
+	return count;
+}
+
+/**
+ * iio_device_register() - register a device with the IIO subsystem
+ * @dev_info:		Device structure filled by the device driver
+ **/
+int iio_device_register(struct iio_dev *dev_info);
+
+/**
+ * iio_device_unregister() - unregister a device from the IIO subsystem
+ * @dev_info:		Device structure representing the device.
+ **/
+void iio_device_unregister(struct iio_dev *dev_info);
+
+/**
+ * struct iio_interrupt - wrapper used to allow easy handling of multiple
+ *			physical interrupt lines
+ * @dev_info:		the iio device for which the is an interrupt line
+ * @line_number:	associated line number
+ * @id:			idr allocated unique id number
+ * @irq:		associate interrupt number
+ * @ev_list:		event handler list for associated events
+ * @ev_list_lock:	ensure only one access to list at a time
+ **/
+struct iio_interrupt {
+	struct iio_dev			*dev_info;
+	int				line_number;
+	int				id;
+	int				irq;
+	struct list_head		ev_list;
+	spinlock_t			ev_list_lock;
+};
+
+#define to_iio_interrupt(i) container_of(i, struct iio_interrupt, ev_list)
+
+/**
+ * iio_register_interrupt_line() - Tell IIO about interrupt lines
+ *
+ * @irq:		Typically provided via platform data
+ * @dev_info:		IIO device info structure for device
+ * @line_number:	Which interrupt line of the device is this?
+ * @type:		Interrupt type (e.g. edge triggered etc)
+ * @name:		Identifying name.
+ **/
+int iio_register_interrupt_line(unsigned int			irq,
+				struct iio_dev			*dev_info,
+				int				line_number,
+				unsigned long			type,
+				const char			*name);
+
+void iio_unregister_interrupt_line(struct iio_dev *dev_info,
+				   int line_number);
+
+
+
+/**
+ * iio_push_event() - try to add event to the list for userspace reading
+ * @dev_info:		IIO device structure
+ * @ev_line:		Which event line (hardware interrupt)
+ * @ev_code:		What event
+ * @timestamp:		When the event occured
+ **/
+int iio_push_event(struct iio_dev *dev_info,
+		  int ev_line,
+		  int ev_code,
+		  s64 timestamp);
+
+/**
+ * struct iio_work_cont - container for when singleton handler case matters
+ * @ws:			[DEVICE]work_struct when not only possible event
+ * @ws_nocheck:		[DEVICE]work_struct when only possible event
+ * @address:		[DEVICE]associated register address
+ * @mask:		[DEVICE]associated mask for identifying event source
+ * @st:			[DEVICE]device specific state information
+ **/
+struct iio_work_cont {
+	struct work_struct	ws;
+	struct work_struct	ws_nocheck;
+	int			address;
+	int			mask;
+	void			*st;
+};
+
+#define to_iio_work_cont_check(_ws)			\
+	container_of(_ws, struct iio_work_cont, ws)
+
+#define to_iio_work_cont_no_check(_ws)				\
+	container_of(_ws, struct iio_work_cont, ws_nocheck)
+
+/**
+ * iio_init_work_cont() - intiialize the elements of a work container
+ * @cont: the work container
+ * @_checkfunc: function called when there are multiple possible int sources
+ * @_nocheckfunc: function for when there is only one int source
+ * @_add: driver dependant, typically a register address
+ * @_mask: driver dependant, typically a bit mask for a register
+ * @_st: driver dependant, typically pointer to a device state structure
+ **/
+static inline void
+iio_init_work_cont(struct iio_work_cont *cont,
+		   void (*_checkfunc)(struct work_struct *),
+		   void (*_nocheckfunc)(struct work_struct *),
+		   int _add, int _mask, void *_st)
+{
+	INIT_WORK(&(cont)->ws, _checkfunc);
+	INIT_WORK(&(cont)->ws_nocheck, _nocheckfunc);
+	cont->address = _add;
+	cont->mask = _mask;
+	cont->st = _st;
+}
+/**
+ * __iio_push_event() tries to add an event to the list associated with a chrdev
+ * @ev_int:		the event interface to which we are pushing the event
+ * @ev_code:		the outgoing event code
+ * @timestamp:		timestamp of the event
+ * @shared_pointer_p:	the shared event pointer
+ **/
+int __iio_push_event(struct iio_event_interface *ev_int,
+		    int ev_code,
+		    s64 timestamp,
+		    struct iio_shared_ev_pointer*
+		    shared_pointer_p);
+/**
+ * __iio_change_event() change an event code in case of event escallation
+ * @ev:			the evnet to be changed
+ * @ev_code:		new event code
+ * @timestamp:		new timestamp
+ **/
+void __iio_change_event(struct iio_detected_event_list *ev,
+			int ev_code,
+			s64 timestamp);
+
+/**
+ * iio_setup_ev_int() Configure an event interface (chrdev)
+ * @name:		name used for resulting sysfs directory etc.
+ * @ev_int:		interface we are configuring
+ * @owner:		module that is responsible for registering this ev_int
+ * @dev:		device whose ev_int this is
+ **/
+int iio_setup_ev_int(struct iio_event_interface *ev_int,
+		     const char *name,
+		     struct module *owner,
+		     struct device *dev);
+
+void iio_free_ev_int(struct iio_event_interface *ev_int);
+
+/**
+ * iio_allocate_chrdev() - Allocate a chrdev
+ * @handler:	struct that contains relevant file handling for chrdev
+ * @dev_info:	iio_dev for which chrdev is being created
+ **/
+int iio_allocate_chrdev(struct iio_handler *handler, struct iio_dev *dev_info);
+void iio_deallocate_chrdev(struct iio_handler *handler);
+
+/* Used to distinguish between bipolar and unipolar scan elemenents.
+ * Whilst this may seem obvious, we may well want to change the representation
+ * in the future!*/
+#define IIO_SIGNED(a) -(a)
+#define IIO_UNSIGNED(a) (a)
+
+extern dev_t iio_devt;
+extern struct class iio_class;
+
+/**
+ * iio_put_device() - reference counted deallocated of struct device
+ * @dev: the iio_device containing the device
+ **/
+static inline void iio_put_device(struct iio_dev *dev)
+{
+	if (dev)
+		put_device(&dev->dev);
+};
+
+/**
+ * to_iio_dev() - get iio_dev for which we have have the struct device
+ * @d: the struct device
+ **/
+static inline struct iio_dev *to_iio_dev(struct device *d)
+{
+	return container_of(d, struct iio_dev, dev);
+};
+
+/**
+ * iio_dev_get_devdata() - helper function gets device specific data
+ * @d: the iio_dev associated with the device
+ **/
+static inline void *iio_dev_get_devdata(struct iio_dev *d)
+{
+	return d->dev_data;
+}
+
+/**
+ * iio_allocate_device() - allocate an iio_dev from a driver
+ **/
+struct iio_dev *iio_allocate_device(void);
+
+/**
+ * iio_free_device() - free an iio_dev from a driver
+ **/
+void iio_free_device(struct iio_dev *dev);
+
+/**
+ * iio_put() - internal module reference count reduce
+ **/
+void iio_put(void);
+
+/**
+ * iio_get() - internal module reference count increase
+ **/
+void iio_get(void);
+
+/* Ring buffer related */
+int iio_device_get_chrdev_minor(void);
+void iio_device_free_chrdev_minor(int val);
+
+/**
+ * iio_ring_enabled() helper function to test if any form of ring enabled
+ **/
+static inline bool iio_ring_enabled(struct iio_dev *dev_info)
+{
+	return dev_info->currentmode
+		& (INDIO_RING_TRIGGERED
+		   | INDIO_RING_HARDWARE_BUFFER);
+};
+
+struct idr;
+
+int iio_get_new_idr_val(struct idr *this_idr);
+void iio_free_idr_val(struct idr *this_idr, int id);
+#endif /* _INDUSTRIAL_IO_H_ */