/* 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 #include #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 * @available_scan_masks: [DRIVER] optional array of allowed bitmasks * @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; u32 scan_mask; u32 *available_scan_masks; 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 31 /* note 0 used as error indicator as it doesn't make sense. */ static inline u32 iio_scan_mask_match(u32 *av_masks, u32 mask) { while (*av_masks) { if (!(~*av_masks & mask)) return *av_masks; av_masks++; } return 0; } static inline int iio_scan_mask_query(struct iio_dev *dev_info, int bit) { u32 mask; if (bit > IIO_MAX_SCAN_LENGTH) return -EINVAL; if (!dev_info->scan_mask) return 0; if (dev_info->available_scan_masks) mask = iio_scan_mask_match(dev_info->available_scan_masks, dev_info->scan_mask); else mask = dev_info->scan_mask; if (!mask) return -EINVAL; return !!(mask & (1 << bit)); }; static inline int iio_scan_mask_set(struct iio_dev *dev_info, int bit) { u32 mask; u32 trialmask = dev_info->scan_mask | (1 << bit); if (bit > IIO_MAX_SCAN_LENGTH) return -EINVAL; if (dev_info->available_scan_masks) { mask = iio_scan_mask_match(dev_info->available_scan_masks, trialmask); if (!mask) return -EINVAL; } dev_info->scan_mask = trialmask; 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 occurred **/ 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 dependent, typically a register address * @_mask: driver dependent, typically a bit mask for a register * @_st: driver dependent, 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 escalation * @ev: the event 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 bus_type iio_bus_type; /** * iio_put_device() - reference counted deallocation 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 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 * @dev: the iio_dev associated with the device **/ 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 is enabled * @dev_info: IIO device info structure for device **/ 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_ */