Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755029AbYGWTms (ORCPT ); Wed, 23 Jul 2008 15:42:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754676AbYGWTmh (ORCPT ); Wed, 23 Jul 2008 15:42:37 -0400 Received: from trinity.fluff.org ([89.145.97.151]:41886 "EHLO trinity.fluff.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754591AbYGWTmd (ORCPT ); Wed, 23 Jul 2008 15:42:33 -0400 Date: Wed, 23 Jul 2008 20:42:30 +0100 From: Ben Dooks To: Jonathan Cameron Cc: LKML , spi-devel-general@lists.sourceforge.net, LM Sensors , mgross@linux.intel.com, Dmitry Torokhov , David Brownell , hmh@hmh.eng.br, Jean Delvare , Ben Nizette Subject: Re: [spi-devel-general] [Patch 1/4] Industrialio Core Message-ID: <20080723194230.GE26938@trinity.fluff.org> References: <488763AD.4050400@gmail.com> <488765A5.3040703@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <488765A5.3040703@gmail.com> X-Disclaimer: These are my views alone. X-URL: http://www.fluff.org/ User-Agent: Mutt/1.5.9i X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: ben@trinity.fluff.org X-SA-Exim-Scanned: No (on trinity.fluff.org); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 79270 Lines: 2568 On Wed, Jul 23, 2008 at 06:08:53PM +0100, Jonathan Cameron wrote: > > From: Jonathan Cameron > > Industrialio subsystem core patch. This subsystem is intended to support the use > of (initially) sensors within linux for the purposes of data capture and its use > within control applications. The intention is to provide consistent interfaces > (where it makes sense) with device control occuring through sysfs interfaces and > provision of events to userspace via chrdevs. Currently software ring buffers > are available if the sensor provides a data ready signal or a periodic rtc is > available (and registered with the subsystem in board init code). > > Signed-off-by: Jonathan Cameron > --- > The periodic timer code is a temporary stop gap until a more generic subsystem > becomes available. > > The intention of publishing these patches is to generate feedback both at the > high level of suggestions / comments on the general approach taken by the > subsystem as a whole and at the low level of implementation details. > > Areas that in my view need attention are the software ring buffer (particularly > careful analysis of corner cases and efficiency of it as a storage method). > Although none of the current drivers is capable of filling it in interrupt > context, I can envision some hardware may need to and this will clearly require > some changes. The overall layout of the interfaces (and indeed the code) needs > some work, particularly with a view to cutting down the dependancies if a > given driver doesn't need all of the systems functionality. > > Additional test drivers will obviously assist in working out many of these > issues and I hope to add several more over the comming weeks. > > My sincerest thanks goes to anyone who takes the time to read through or test > this patch set. > > drivers/Kconfig | 3 > drivers/Makefile | 1 > drivers/industrialio/Kconfig | 19 > drivers/industrialio/Makefile | 7 > drivers/industrialio/industrialio-core.c | 787 ++++++++++++++++++ > drivers/industrialio/industrialio-ring.c | 770 +++++++++++++++++ > drivers/industrialio/industrialio-rtc.c | 134 +++ > drivers/industrialio/industrialio_ptimer_board_info.c | 44 + > include/linux/industrialio.h | 374 ++++++++ > include/linux/industrialio_ptimer.h | 18 > include/linux/industrialio_sysfs.h | 274 ++++++ > 11 files changed, 2431 insertions(+) > > ------ a/drivers/Kconfig 2008-07-13 22:51:29.000000000 +0100 > +++ b/drivers/Kconfig 2008-07-14 17:26:34.000000000 +0100 > @@ -101,4 +101,7 @@ source "drivers/auxdisplay/Kconfig" > source "drivers/uio/Kconfig" > > source "drivers/xen/Kconfig" > + > +source "drivers/industrialio/Kconfig" > endmenu > + > --- a/drivers/Makefile 2008-07-13 22:51:29.000000000 +0100 > +++ b/drivers/Makefile 2008-07-14 17:26:34.000000000 +0100 > @@ -62,6 +62,7 @@ obj-$(CONFIG_INPUT) += input/ > obj-$(CONFIG_I2O) += message/ > obj-$(CONFIG_RTC_LIB) += rtc/ > obj-y += i2c/ > +obj-y += industrialio/ > obj-$(CONFIG_W1) += w1/ > obj-$(CONFIG_POWER_SUPPLY) += power/ > obj-$(CONFIG_HWMON) += hwmon/ > --- a/drivers/industrialio/Kconfig 1970-01-01 01:00:00.000000000 +0100 > +++ b/drivers/industrialio/Kconfig 2008-07-23 15:44:45.000000000 +0100 > @@ -0,0 +1,19 @@ > +# > +# Industrial I/O subsytem configuration > +# > + > +menuconfig INDUSTRIALIO > + tristate "Industrial I/O support" > + ---help--- > + The industrial IO subsystem provides a unified framework for drivers > + for many different types of embedded sensors using a number of > + different phyiscal interfaces (i2c, spi etc). See > + Documentation/industrialio for more information. > + > +if INDUSTRIALIO > + > +config INDUSTRIALIO_PTIMER_BOARDINFO > + boolean > + default y > + > +endif > --- a/drivers/industrialio/Makefile 1970-01-01 01:00:00.000000000 +0100 > +++ b/drivers/industrialio/Makefile 2008-07-23 12:05:27.000000000 +0100 > @@ -0,0 +1,7 @@ > +# > +# Makefile for the industrial I/O core. > +# > +industrialio-objs := industrialio-core.o industrialio-ring.o industrialio-rtc.o > + > +obj-$(CONFIG_INDUSTRIALIO) += industrialio.o > +obj-$(CONFIG_INDUSTRIALIO_PTIMER_BOARDINFO) += industrialio_ptimer_board_info.o > --- a/include/linux/industrialio.h 1970-01-01 01:00:00.000000000 +0100 > +++ b/include/linux/industrialio.h 2008-07-23 15:20:19.000000000 +0100 > @@ -0,0 +1,374 @@ > +/* 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 > + > +/* TODO LIST */ > +/* Static device specific elements (conversion factors etc) > + should be exported via sysfs > + Break up this header - some drivers only want a fraction of this. > +*/ > + > + > +/* Event interface flags */ > +#define IIO_BUSY_BIT_POS 1 > + > + > +struct iio_handler { > + const struct file_operations *fops; > + int id; > + unsigned long flags; > + void *private; > +}; > + > +/* The actual event being pushed ot userspace */ > +struct iio_event_data { > + int id; > + s64 timestamp; > +}; So is this an header for an event? Where is the data in this, this is confusing... Also, should we have a framework to produce an key/pair data, so that an single event can export multiple values from one event... ie: struct event_header { unsigned int id; unsigned int nr_data; /* number of event_data after */ s64 timestamp; struct event { struct event_header header; struct event_data data[0]; }; > + > +struct iio_detected_event_list { > + struct list_head list; > + struct iio_event_data ev; > + /* Part of shared event handling - (typicaly ring buffers) */ > + struct iio_shared_ev_pointer *shared_pointer; > +}; the naming of these structures is rather long. > +/* Requires high resolution timers */ > +/* TODO - provide alternative if not available? */ > +static inline s64 iio_get_time_ns(void) > +{ > + struct timespec ts; > + ktime_get_ts(&ts); > + return timespec_to_ns(&ts); > +} do we really need something that accurate? we should at-least have the option to remove the timestamp or choose something of lower accuracy? > +struct iio_dev; > + > +/* Each device has one of these per interrupt */ > +struct iio_event_handler_list { > + struct list_head list; > + int (*handler)(struct iio_dev *dev_io, int index, s64 timestamp, > + int no_test); > + /* This element may be shared */ > + int refcount; > +}; > + > +/* Wraps adding to lists and does reference counting to allowed shared > + * handlers. > + */ > +int iio_add_event_to_list(struct iio_event_handler_list *list, > + struct iio_event_handler_list *el); > + > +int iio_remove_event_from_list(struct iio_event_handler_list *el); > + > +struct iio_sw_ring_buffer; > +struct iio_hw_ring_buffer; > + > +#define INIT_IIO_RING_BUFFER(ring_buf, _bytes_per_datum, _length) { \ > + (ring_buf)->size = _bytes_per_datum; \ > + (ring_buf)->length = _length; \ > + (ring_buf)->loopcount = 0; \ > + (ring_buf)->shared_ev_pointer.ev_p = 0; \ > + (ring_buf)->shared_ev_pointer.lock = \ > + __SPIN_LOCK_UNLOCKED((ring_buf) \ > + ->shared_ev_pointer->loc); \ > + } > + > +#define INIT_IIO_SW_RING_BUFFER(ring, _bytes_per_datum, _length) { \ > + INIT_IIO_RING_BUFFER(&(ring)->buf, \ > + _bytes_per_datum, \ > + _length); \ > + (ring)->read_p = 0; \ > + (ring)->write_p = 0; \ > + (ring)->last_written_p = 0; \ > + (ring)->data = kmalloc(_length*(ring)->buf.size, \ > + GFP_KERNEL); \ > + (ring)->use_count = 0; \ > + (ring)->use_lock = __SPIN_LOCK_UNLOCKED((ring)->use_lock); \ > + } these should be inlined functions. > +#define FREE_IIO_SW_RING_BUFFER(ring) kfree((ring)->data) > + > + > + > +int iio_store_to_sw_ring(struct iio_sw_ring_buffer *ring, > + unsigned char *data, > + s64 timestamp); > + > +/* Edge cases : > + 1) data at last_p is no longer valid - requires complete wrap around. > + To detect, loop count has changed - if only by 1 then problem only > + if current_lastp is equal to or greater than copy made at start. > + If we have wrapped an entire int in this time (loopcount) then > + something very very weird has occured! > +*/ > +int iio_read_last_from_sw_ring(struct iio_sw_ring_buffer *ring, > + unsigned char *data); > + > +/* Up to the drivers to mark the ring whenever it must not change size > + * and unmark when it may without problems */ > +void iio_mark_sw_ring_buffer_in_use(struct iio_sw_ring_buffer *ring); > + > +void iio_unmark_sw_ring_buffer_in_use(struct iio_sw_ring_buffer *ring); > + > +int iio_request_sw_ring_buffer(int bytes_per_datum, > + int length, > + struct iio_sw_ring_buffer **ring, > + int id, > + struct module *owner, > + struct device *dev); > + how about tying this to a driver, where you already know the owner and the dev? > +int iio_request_update_sw_ring_buffer(struct iio_dev *dev_info, int id); > + > +void iio_free_sw_ring_buffer(struct iio_sw_ring_buffer *ring, > + struct device *dev); > + > +int iio_request_hw_ring_buffer(int bytes_per_datum, > + int length, > + struct iio_hw_ring_buffer **ring, > + int id, > + struct module *owner, > + struct device *dev, > + const struct file_operations *fops, > + void *private); > + > +void iio_free_hw_ring_buffer(struct iio_hw_ring_buffer *ring, > + struct device *dev); > + > +/* Device operating modes */ > +#define INDIO_DIRECT_MODE 0x01 > +#define INDIO_RING_POLLED 0x02 > +#define INDIO_RING_DATA_RDY 0x04 > +#define INDIO_RING_HARDWARE_BUFFER 0x08 > + > +struct iio_event_interface { > + struct iio_handler handler; > + wait_queue_head_t wait; > + struct mutex event_list_lock; > + struct iio_detected_event_list det_events; > + int max_events; > + int current_events; > + /* Integer id, used to differentiate this one form any others */ > + int id; > + struct iio_chrdev_minor_attr attr; > + struct module *owner; > + void *private; > + /* used to store name for associated sysfs file */ > + char _name[20]; > +}; > + > +struct iio_shared_ev_pointer { > + struct iio_detected_event_list *ev_p; > + spinlock_t lock; > +}; > + > +/* A general ring buffer structure > + * Intended to be completely lock free as we always want fills from > + * the interrupt handler to not have to wait. This obviously increases > + * the possible time required to read from the buffer. */ > +struct iio_ring_buffer { > + /* Number of datums */ > + int length; > + /* length of single datum - including timestamp if there */ > + int size; > + int loopcount; > + /* accessing the ring buffer */ > + char *access_minor_name; > + struct iio_chrdev_minor_attr access_minor_attr; > + struct iio_handler access_handler; > + /* events triggered by the ring buffer */ > + char *event_minor_name; > + struct iio_event_interface ev_int; > + /* a fully shared output event ? wtf?*/ > + struct iio_shared_ev_pointer shared_ev_pointer; > +}; > + > +int iio_put_ring_event(struct iio_ring_buffer *ring_buf, > + int event_code, > + s64 timestamp); > + > +int iio_put_or_escallate_ring_event(struct iio_ring_buffer *ring_buf, > + int event_code, > + s64 timestamp); > + > +struct iio_sw_ring_buffer { > + struct iio_ring_buffer buf; > + unsigned char *data; > + unsigned char *read_p; > + unsigned char *write_p; > + unsigned char *last_written_p; > + /* used to act as a point at which to signal an event */ > + unsigned char *half_p; > + int use_count; > + int update_needed; > + spinlock_t use_lock; > +}; > + > +struct iio_hw_ring_buffer { > + struct iio_ring_buffer buf; > + void *private; > +}; > + > +/* Vast majority of this is set by the industrialio subsystem on a > + * call to iio_device_register. */ > +/* TODO Macros to simplify setting the relevant stuff in the driver. */ > +struct iio_dev { > +/* generic handling data used by ind io */ > + int id; > +/* device specific data */ > + void *dev_data; > + > +/* Modes the drivers supports */ > + int modes; /* Driver Set */ > + int currentmode; > +/* Direct sysfs related functionality */ > + struct device *sysfs_dev; > + struct device *dev; /* Driver Set */ > + /* General attributes */ > + const struct attribute_group *attrs; > + > +/* Interrupt handling related */ > + struct module *driver_module; > + int num_interrupt_lines; /* Driver Set */ > + > + struct iio_interrupt **interrupts; > + > + > + /* Event control attributes */ > + struct attribute_group *event_attrs; > + /* The character device related elements */ > + struct iio_event_interface *event_interfaces; > + > +/* Software Ring Buffer > + - for now assuming only makes sense to have a single ring */ > + int ring_dimension; > + int ring_bytes_per_datum; > + int ring_length; > + struct iio_sw_ring_buffer *ring; > + struct attribute_group *ring_attrs_group; > + struct iio_ring_attr *ring_attrs; > + /* enabling / disabling related functions. > + * post / pre refer to relative to the change of current_mode. */ > + int (*ring_preenable)(struct iio_dev *); > + int (*ring_postenable)(struct iio_dev *); > + int (*ring_predisable)(struct iio_dev *); > + int (*ring_postdisable)(struct iio_dev *); > + void (*ring_poll_func)(void *private_data); > + struct iio_periodic *ptimer; > + > + /* Device state lock. > + * Used to prevent simultaneous changes to device state. > + * In here rather than modules as some ring buffer changes must occur > + * with this locked.*/ > + struct mutex mlock; > + > + /* Name used to allow releasing of the relevant ptimer on exit. > + * Ideally the ptimers will only be held when the driver is actually > + * using them, but for now they have one the whole time they are loaded. > + */ > + const char *ptimer_name; > +}; > + > +int iio_device_register(struct iio_dev *dev_info); > +void iio_device_unregister(struct iio_dev *dev_info); > + > +/* Wrapper class used to allow easy specification of different line numbers */ > +struct iio_interrupt { > + struct iio_dev *dev_info; > + int line_number; > + int irq; > + struct iio_event_handler_list ev_list; > +}; > + > +irqreturn_t iio_interrupt_handler(int irq, void *_int_info); > + > +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); > + > + > +/* Used to try inserting an event into the list for userspace reading via > + * chrdev */ > +int iio_put_event(struct iio_dev *dev_info, > + int ev_line, > + int ev_code, > + s64 timestamp); > + > +struct iio_work_cont { > + struct work_struct ws; > + struct work_struct ws_nocheck; > + int address; > + int mask; > + void *st; > +}; > +#define INIT_IIO_WORK_CONT(cont, _checkfunc, _nocheckfunc, _add, _mask, _st)\ > + do { \ > + INIT_WORK(&(cont)->ws, _checkfunc); \ > + INIT_WORK(&(cont)->ws_nocheck, _nocheckfunc); \ > + (cont)->address = _add; \ > + (cont)->mask = _mask; \ > + (cont)->st = _st; \ > + } while (0) more nasty macros. > +/* Ring buffer related */ > +int iio_device_register_sw_ring(struct iio_dev *dev_info, int id); > +void iio_device_unregister_sw_ring(struct iio_dev *dev_info); > + > +int __iio_put_event(struct iio_event_interface *ev_int, > + int ev_code, > + s64 timestamp, > + struct iio_shared_ev_pointer* > + shared_pointer_p); > +void __iio_change_event(struct iio_detected_event_list *ev, > + int ev_code, > + s64 timestamp); > + > +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, struct device *dev); > + > +int iio_allocate_chrdev(struct iio_handler *handler); > +void iio_deallocate_chrdev(struct iio_handler *handler); > + > +ssize_t iio_show_attr_minor(struct device *dev, > + struct device_attribute *attr, > + char *buf); > + > +/* For now this is on the type of periodic timer used*/ > +struct iio_periodic { > + struct rtc_device *rtc; > + int frequency; > + struct rtc_task task; > +}; > + > +int iio_ptimer_request_periodic_timer(char *name, struct iio_dev *indio_dev); > +void iio_ptimer_unrequest_periodic_timer(struct iio_dev *indio_dev); > +int iio_ptimer_set_freq(struct iio_periodic *ptimer, unsigned frequency); > +int iio_ptimer_irq_set_state(struct iio_dev *indio_dev, bool state); > + > +/* Board registration is handled by contents of > + * industrialio_ptimer_board_info.c > + */ > +extern struct mutex industrialio_ptimer_board_lock; > +extern struct list_head industrialio_ptimer_board_info_list; > +#endif /* _INDUSTRIAL_IO_H_ */ > --- a/include/linux/industrialio_ptimer.h 1970-01-01 01:00:00.000000000 +0100 > +++ b/include/linux/industrialio_ptimer.h 2008-07-23 15:41:29.000000000 +0100 > @@ -0,0 +1,18 @@ > +#ifndef _INDUSTRIALIO_PTIMER_H_ > +#define _INDUSTRIALIO_PTIMER_H_ > + > +#define IIO_PTIMER_NAME_SIZE 10 > + > + > +struct ptimer_info { > + char name[IIO_PTIMER_NAME_SIZE]; > +}; > +struct ptimer_info_listel { > + struct list_head list; > + bool inuse; > + struct ptimer_info info; > +}; > + > +extern int > +industrialio_register_ptimer(struct ptimer_info const *info, unsigned n); > +#endif > --- a/include/linux/industrialio_sysfs.h 1970-01-01 01:00:00.000000000 +0100 > +++ b/include/linux/industrialio_sysfs.h 2008-07-23 16:04:18.000000000 +0100 > @@ -0,0 +1,274 @@ > +/* 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. > + * > + * General attributes > + */ > + > +#ifndef _INDUSTRIAL_IO_SYSFS_H_ > +#define _INDUSTRIAL_IO_SYSFS_H_ > + > +#include > + > + > +struct iio_event_attr { > + struct device_attribute dev_attr; > + int mask; > + struct iio_event_handler_list *listel; > +}; > + > + > +#define to_iio_event_attr(_dev_attr) \ > + container_of(_dev_attr, struct iio_event_attr, dev_attr) > + > + > +struct iio_chrdev_minor_attr { > + struct device_attribute dev_attr; > + int minor; > +}; > + > +void > +__init_iio_chrdev_minor_attr(struct iio_chrdev_minor_attr *minor_attr, > + const char *name, > + struct module *owner, > + int id); > + > + > +#define to_iio_chrdev_minor_attr(_dev_attr) \ > + container_of(_dev_attr, struct iio_chrdev_minor_attr, dev_attr); > + > +struct iio_dev_attr { > + struct device_attribute dev_attr; > + int address; > +}; > + > + > +#define to_iio_dev_attr(_dev_attr) \ > + container_of(_dev_attr, struct iio_dev_attr, dev_attr) > + > +/* Some attributes will be hard coded (device dependant) and not require an > + address, in these cases pass a negative */ > +#define IIO_ATTR(_name, _mode, _show, _store, _addr) \ > + { .dev_attr = __ATTR(_name, _mode, _show, _store), \ > + .address = _addr } > + > +#define IIO_DEVICE_ATTR(_name, _mode, _show, _store, _addr) \ > + struct iio_dev_attr iio_dev_attr_##_name \ > + = IIO_ATTR(_name, _mode, _show, _store, _addr) > + > +/* This may get broken down into separate files later */ > + > +/* Generic attributes of onetype or another */ > + > +/* Revision number for the device. As the form of this varies greatly from > + * device to device, no particular form is specified. In most cases this will > + * only be for information to the user, not to effect functionality etc. > + */ > +#define IIO_DEV_ATTR_REV(_show) \ > + IIO_DEVICE_ATTR(revision, S_IRUGO, _show, NULL, 0) > + > +/* For devices with internal clocks - and possibly poling later */ > + > +#define IIO_DEV_ATTR_SAMP_FREQ(_mode, _show, _store) \ > + IIO_DEVICE_ATTR(sampling_frequency, _mode, _show, _store, 0) > + > +#define IIO_DEV_ATTR_AVAIL_SAMP_FREQ(_show) \ > + IIO_DEVICE_ATTR(available_sampling_frequency, S_IRUGO, _show, NULL, 0) > + > +/* ADC types of attibute */ > + > +#define IIO_DEV_ATTR_AVAIL_SCAN_MODES(_show) \ > + IIO_DEVICE_ATTR(available_scan_modes, S_IRUGO, _show, NULL, 0) > + > +#define IIO_DEV_ATTR_SCAN_MODE(_mode, _show, _store) \ > + IIO_DEVICE_ATTR(scan_mode, _mode, _show, _store, 0) > + > +#define IIO_DEV_ATTR_INPUT(_number, _show) \ > + IIO_DEVICE_ATTR(in##_number, S_IRUGO, _show, NULL, _number) > + > +#define IIO_DEV_ATTR_SCAN(_show) \ > + IIO_DEVICE_ATTR(scan, S_IRUGO, _show, NULL, 0); > +/* Accelerometer types of attribute */ > + > +#define IIO_DEV_ATTR_ACCEL_X_OFFSET(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(x_offset, _mode, _show, _store, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_Y_OFFSET(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(y_offset, _mode, _show, _store, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_Z_OFFSET(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(z_offset, _mode, _show, _store, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_X_GAIN(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(x_gain, _mode, _show, _store, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_Y_GAIN(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(y_gain, _mode, _show, _store, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_Z_GAIN(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(z_gain, _mode, _show, _store, _addr) > + > + > +/* The actual device readings are always going to be read only */ > +#define IIO_DEV_ATTR_ACCEL_X(_show, _addr) \ > + IIO_DEVICE_ATTR(x, S_IRUGO, _show, NULL, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_Y(_show, _addr) \ > + IIO_DEVICE_ATTR(y, S_IRUGO, _show, NULL, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_Z(_show, _addr) \ > + IIO_DEVICE_ATTR(z, S_IRUGO, _show, NULL, _addr) > + > +#define IIO_DEV_ATTR_TEMP(_show) \ > + IIO_DEVICE_ATTR(temp, S_IRUGO, _show, NULL, 0) > +/* Thresholds are somewhat chip dependent - may need quite a few defs here */ > +/* For unified thesholds (shared across all directions */ > +#define IIO_DEV_ATTR_ACCEL_THRESH(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(thresh, _mode, _show, _store, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_THRESH_X(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(thresh_x, _mode, _show, _store, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_THRESH_Y(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(thresh_y, _mode, _show, _store, _addr) > + > +#define IIO_DEV_ATTR_ACCEL_THRESH_Z(_mode, _show, _store, _addr) \ > + IIO_DEVICE_ATTR(thresh_z, _mode, _show, _store, _addr) > + > +/* This is an event attr in some case and a dev in others - FIX*/ > +#define IIO_DEV_ATTR_SW_RING_ENABLE(_show, _store) \ > + IIO_DEVICE_ATTR(sw_ring_enable, S_IRUGO | S_IWUSR, _show, _store, 0) > + > +/* Hardware ring buffer related attributes */ > +#define IIO_DEV_ATTR_HW_RING_ENABLE(_show, _store) \ > + IIO_DEVICE_ATTR(hw_ring_enable, S_IRUGO | S_IWUSR, _show, _store, 0) > + > +#define IIO_DEV_ATTR_RING_BPS(_mode, _show, _store) \ > + IIO_DEVICE_ATTR(ring_bps, _mode, _show, _store, 0) > + > +/* Bits per sample */ > +#define IIO_DEV_ATTR_RING_BPS_AVAILABLE(_show) \ > + IIO_DEVICE_ATTR(ring_bps_available, S_IRUGO, _show, NULL, 0) > + > +/* Events that the device may generate */ > + > +#define IIO_EVENT_SH(_name, _handler) \ > + static struct iio_event_handler_list \ > + iio_event_##_name = { \ > + .handler = _handler, \ > + .refcount = 0, \ > + }; > +#define IIO_EVENT_ATTR_SH(_name, _ev_list, _show, _store, _mask) \ > + static struct iio_event_attr \ > + iio_event_attr_##_name \ > + = { .dev_attr = __ATTR(_name, S_IRUGO | S_IWUSR, _show, _store),\ > + .mask = _mask,\ > + .listel = &_ev_list }; > + > +/*FIXME use the above to define this */ > +#define IIO_EVENT_ATTR(_name, _show, _store, _mask, _handler) \ > + static struct iio_event_handler_list \ > + iio_event_##_name = { \ > + .handler = _handler, \ > + }; \ > + static struct \ > + iio_event_attr \ > + iio_event_attr_##_name \ > + = { .dev_attr = __ATTR(_name, S_IRUGO | S_IWUSR, _show, _store), \ > + .mask = _mask, \ > + .listel = &iio_event_##_name }; \ > +/*FIXME, add line number to the above?*/ > + > +/* In most of these cases, this actually corresponds to something with a > + value attached */ > + > +/* For some devices you can select whether all conditions or any condition > + must be met for interrupt generation */ > +#define IIO_EVENT_ATTR_DATA_RDY(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(data_rdy, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_CODE_DATA_RDY 100 > + > +/* Threshold pass events */ > +#define IIO_EVENT_ATTR_ACCEL_X_HIGH(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(x_high, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_CODE_ACCEL_X_HIGH 1 > + > +/* Shared handler version */ > +#define IIO_EVENT_ATTR_ACCEL_X_HIGH_SH(_evlist, _show, _store, _mask)\ > + IIO_EVENT_ATTR_SH(x_high, _evlist, _show, _store, _mask) > + > + > +#define IIO_EVENT_ATTR_ACCEL_Y_HIGH(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(y_high, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_ATTR_ACCEL_Y_HIGH_SH(_evlist, _show, _store, _mask)\ > + IIO_EVENT_ATTR_SH(y_high, _evlist, _show, _store, _mask) > + > +#define IIO_EVENT_CODE_ACCEL_Y_HIGH 2 > + > +#define IIO_EVENT_ATTR_ACCEL_Z_HIGH(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(z_high, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_ATTR_ACCEL_Z_HIGH_SH(_evlist, _show, _store, _mask)\ > + IIO_EVENT_ATTR_SH(z_high, _evlist, _show, _store, _mask) > + > +#define IIO_EVENT_CODE_ACCEL_Z_HIGH 3 > + > +#define IIO_EVENT_ATTR_ACCEL_X_LOW(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(x_low, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_ATTR_ACCEL_X_LOW_SH(_evlist, _show, _store, _mask)\ > + IIO_EVENT_ATTR_SH(x_low, _evlist, _show, _store, _mask) > + > +#define IIO_EVENT_CODE_ACCEL_X_LOW 4 > + > +#define IIO_EVENT_ATTR_ACCEL_Y_LOW(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(y_low, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_ATTR_ACCEL_Y_LOW_SH(_evlist, _show, _store, _mask)\ > + IIO_EVENT_ATTR_SH(y_low, _evlist, _show, _store, _mask) > + > +#define IIO_EVENT_CODE_ACCEL_Y_LOW 5 > + > +#define IIO_EVENT_ATTR_ACCEL_Z_LOW(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(z_low, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_ATTR_ACCEL_Z_LOW_SH(_evlist, _show, _store, _mask) \ > + IIO_EVENT_ATTR_SH(z_low, _evlist, _show, _store, _mask) > + > +#define IIO_EVENT_CODE_ACCEL_Z_LOW 6 > + > +#define IIO_EVENT_ATTR_FREE_FALL_DETECT(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(free_fall, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_ATTR_FREE_FALL_DETECT_SH(_evlist, _show, _store, _mask) \ > + IIO_EVENT_ATTR_SH(free_fall, _evlist, _show, _store, _mask) > + > +#define IIO_EVENT_CODE_FREE_FALL 7 > + > +/* These may be software or hardware events depending on type of ring buffer */ > + > +#define IIO_EVENT_ATTR_RING_50_FULL(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(ring_50_full, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_ATTR_RING_50_FULL_SH(_evlist, _show, _store, _mask) \ > + IIO_EVENT_ATTR_SH(ring_50_full, _evlist, _show, _store, _mask) > + > +#define IIO_EVENT_ATTR_RING_75_FULL_SH(_evlist, _show, _store, _mask) \ > + IIO_EVENT_ATTR_SH(ring_75_full, _evlist, _show, _store, _mask) > + > +#define IIO_EVENT_ATTR_SW_RING_ENABLE(_show, _store, _mask, _handler) \ > + IIO_EVENT_ATTR(sw_ring_enable, _show, _store, _mask, _handler) > + > +#define IIO_EVENT_CODE_RING_50_FULL 100 > +#define IIO_EVENT_CODE_RING_75_FULL 101 > +#define IIO_EVENT_CODE_RING_100_FULL 102 > +/* HOW TO HANDLE COMPOSITE EVENTS? */ > + > +#endif /* _INDUSTRIAL_IO_SYSFS_H_ */ > --- a/drivers/industrialio/industrialio_ptimer_board_info.c 1970-01-01 01:00:00.000000000 +0100 > +++ b/drivers/industrialio/industrialio_ptimer_board_info.c 2008-07-23 14:16:28.000000000 +0100 > @@ -0,0 +1,44 @@ > +/* The industrial I/O periodic timer registration code > + * > + * 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. > + * > + */ > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +LIST_HEAD(industrialio_ptimer_board_info_list); > +EXPORT_SYMBOL_GPL(industrialio_ptimer_board_info_list); > + > +DEFINE_MUTEX(industrialio_ptimer_board_lock); > +EXPORT_SYMBOL_GPL(industrialio_ptimer_board_lock); > + > + > +int __init > +industrialio_register_ptimer(struct ptimer_info const *info, unsigned n) > +{ > + int i; > + struct ptimer_info_listel *pi; > + > + mutex_lock(&industrialio_ptimer_board_lock); > + for (i = 0; i < n; i++) { > + pi = kzalloc(sizeof(*pi), GFP_KERNEL); > + if (!pi) { > + mutex_unlock(&industrialio_ptimer_board_lock); > + return -ENOMEM; > + } > + strncpy(pi->info.name, info[i].name, IIO_PTIMER_NAME_SIZE); > + list_add_tail(&pi->list, &industrialio_ptimer_board_info_list); > + } > + mutex_unlock(&industrialio_ptimer_board_lock); > + > + return 0; > +} > --- a/drivers/industrialio/industrialio-core.c 1970-01-01 01:00:00.000000000 +0100 > +++ b/drivers/industrialio/industrialio-core.c 2008-07-23 15:07:21.000000000 +0100 > @@ -0,0 +1,787 @@ > +/* 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. > + * > + * Based on elements of hwmon and input subsystems. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > + > +MODULE_AUTHOR("Jonathan Cameron "); > +MODULE_DESCRIPTION("Industrial I/O core"); > +MODULE_LICENSE("GPL"); > + > +#define IIO_ID_PREFIX "industrialio" > +#define IIO_ID_FORMAT IIO_ID_PREFIX "%d" > +#define IIO_MAJOR 244 > + > +/* Integer id - used to assign each registered device a unique id*/ > +static DEFINE_IDR(iio_idr); > +static DEFINE_SPINLOCK(iio_idr_lock); > + > +struct class iio_class = { > + .name = "industrialio", > +}; > + > +/* Struct used to maintain internal state about industrialio. > + * This will be used to handle the character device accesses > + * and redirect them to the relevant driver. > + * Will reduce this to the included table if nothing else comes > + * up that should go in here! > + */ > +struct __iio_state { > + /* All initially set to NULL in init */ > + struct iio_handler *fhs[256]; > +}; > + > +static struct __iio_state iio_state; > +static DEFINE_SPINLOCK(iio_state_lock); > + > +/* Used to escalate shared event. > + * Currently this is only used with ring buffer events. > + */ > +void __iio_change_event(struct iio_detected_event_list *ev, > + int ev_code, > + s64 timestamp) > +{ > + ev->ev.id = ev_code; > + ev->ev.timestamp = timestamp; > +} > + > +/* Used both in the interrupt line put events and the ring buffer ones */ > + int > +__iio_put_event(struct iio_event_interface *ev_int, > + int ev_code, > + s64 timestamp, > + struct iio_shared_ev_pointer* > + shared_pointer_p) > +{ > + struct iio_detected_event_list *ev; > + int ret; > + > + /* Does anyone care? */ > + if (test_bit(IIO_BUSY_BIT_POS, &ev_int->handler.flags)) { > + if (ev_int->current_events == ev_int->max_events) > + return 0; > + ev = kmalloc(sizeof(struct iio_detected_event_list), > + GFP_KERNEL); > + if (ev == NULL) { > + ret = -ENOMEM; > + goto error_ret; > + } > + ev->ev.id = ev_code; > + ev->ev.timestamp = timestamp; > + if (shared_pointer_p != NULL) { > + ev->shared_pointer = shared_pointer_p; > + shared_pointer_p->ev_p = ev; > + } else > + ev->shared_pointer = NULL; > + > + mutex_lock(&ev_int->event_list_lock); > + list_add_tail(&ev->list, &ev_int->det_events.list); > + mutex_unlock(&ev_int->event_list_lock); > + > + ev_int->current_events++; > + wake_up_interruptible(&ev_int->wait); > + } > + > + return 0; > +error_ret: > + return ret; > + > +} > + > +int iio_put_event(struct iio_dev *dev_info, > + int ev_line, > + int ev_code, > + s64 timestamp) > +{ > + return __iio_put_event(&dev_info->event_interfaces[ev_line], > + ev_code, timestamp, NULL); > +} > +EXPORT_SYMBOL(iio_put_event); > + > +/* Confirming the validity of supplied irq is left to drivers.*/ > +int iio_register_interrupt_line(unsigned int irq, > + struct iio_dev *dev_info, > + int line_number, > + unsigned long type, > + const char *name) > +{ > + int ret; > + > + dev_info->interrupts[line_number] = > + kmalloc(sizeof(struct iio_interrupt), GFP_KERNEL); > + if (dev_info->interrupts[line_number] == NULL) { > + ret = -ENOMEM; > + goto error_ret; > + } > + > + INIT_LIST_HEAD(&dev_info->interrupts[line_number]->ev_list.list); > + dev_info->interrupts[line_number]->line_number = line_number; > + dev_info->interrupts[line_number]->irq = irq; > + dev_info->interrupts[line_number]->dev_info = dev_info; > + > + /* Possibly only request on demand? > + * Can see this may complicate the handling of interrupts. > + * However, with this approach we end up handling lots of > + * events no-one cares about.*/ > + ret = request_irq(irq, > + &iio_interrupt_handler, > + type, > + name, > + dev_info->interrupts[line_number]); > + if (ret < 0) > + goto error_ret; > + > + return 0; > + > +error_ret: > + return ret; > +} > +EXPORT_SYMBOL(iio_register_interrupt_line); > + > +/* Before this runs the interrupt generator must have been disabled */ > +void iio_unregister_interrupt_line(struct iio_dev *dev_info, > + int line_number) > +{ > + /* make sure the interrupt handlers are all done */ > + flush_scheduled_work(); > + free_irq(dev_info->interrupts[line_number]->irq, > + dev_info->interrupts[line_number]); > + kfree(dev_info->interrupts[line_number]); > +} > +EXPORT_SYMBOL(iio_unregister_interrupt_line); > + > +/* Generic interrupt line interrupt handler */ > +irqreturn_t iio_interrupt_handler(int irq, void *_int_info) > +{ > + struct iio_interrupt *int_info = _int_info; > + struct iio_dev *dev_info = int_info->dev_info; > + struct iio_event_handler_list *p; > + s64 time_ns; > + > + if (list_empty(&int_info->ev_list.list)) > + return IRQ_NONE; > + > + time_ns = iio_get_time_ns(); > + /* detect single element list*/ > + if (int_info->ev_list.list.next->next == &int_info->ev_list.list) { > + disable_irq_nosync(irq); > + p = list_first_entry(&int_info->ev_list.list, > + struct iio_event_handler_list, > + list); > + p->handler(dev_info, 1, time_ns, 1); > + } else > + list_for_each_entry(p, &int_info->ev_list.list, list) { > + disable_irq_nosync(irq); > + p->handler(dev_info, 1, time_ns, 0); > + } > + return IRQ_HANDLED; > +} > +EXPORT_SYMBOL(iio_interrupt_handler); > + > +int iio_add_event_to_list(struct iio_event_handler_list *list, > + struct iio_event_handler_list *el) > +{ > + if (el->refcount == 0) > + list_add(&list->list, &el->list); > + el->refcount++; > + return 0; > +} > +EXPORT_SYMBOL_GPL(iio_add_event_to_list); > + > +int iio_remove_event_from_list(struct iio_event_handler_list > + *el) > +{ > + el->refcount--; > + if (el->refcount == 0) > + list_del_init(&el->list); > + return 0; > +} > +EXPORT_SYMBOL_GPL(iio_remove_event_from_list); > + > + > +int iio_allocate_chrdev(struct iio_handler *handler) > +{ > + int id; > + > + spin_lock(iio_state_lock); > + for (id = 0; id <= 256; id++) > + if (iio_state.fhs[id] == NULL) > + break; > + if (id == 256) { > + spin_unlock(iio_state_lock); > + return -ENOMEM; > + } > + iio_state.fhs[id] = handler; > + spin_unlock(iio_state_lock); > + handler->id = id; > + > + return 0; > +} > + > +void iio_deallocate_chrdev(struct iio_handler *handler) > +{ > + spin_lock(iio_state_lock); > + iio_state.fhs[handler->id] = NULL; > + spin_unlock(iio_state_lock); > +} > + > +/* Upon open, switch in the correct file ops > + * lifted directly from input subsystem */ > +static int iio_open_file(struct inode *inode, struct file *file) > +{ > + struct iio_handler *handler; > + const struct file_operations *old_fops, *new_fops = NULL; > + int err; > + > + /* This lock needed as unlike input we are dynamically allocating > + * chrdevs */ > + spin_lock(iio_state_lock); > + handler = iio_state.fhs[iminor(inode)]; > + spin_unlock(iio_state_lock); > + > + if (!handler) { > + fops_put(file->f_op); > + return -ENODEV; > + } > + new_fops = fops_get(handler->fops); > + if (new_fops == NULL) { > + fops_put(file->f_op); > + return -ENODEV; > + } > + > + /* cribbed from lp.c */ > + if (test_and_set_bit(IIO_BUSY_BIT_POS, &handler->flags)) { > + fops_put(file->f_op); > + return -EBUSY; > + } > + > + if (!new_fops->open) { > + fops_put(new_fops); > + return -ENODEV; > + } > + old_fops = file->f_op; > + file->f_op = new_fops; > + /* use the private data pointer in file to give access to device > + * specific stuff */ > + file->private_data = handler->private; > + err = new_fops->open(inode, file); > + > + if (err) { > + fops_put(file->f_op); > + file->f_op = fops_get(old_fops); > + } > + fops_put(old_fops); > + > + return err; > +} > + > + > +/* The main file ops structure. All open calls on the major number will > + * be handled by this with fops for the actual minor number assigned by > + * switching function above */ > +static const struct file_operations iio_fops = { > + .owner = THIS_MODULE, > + .open = iio_open_file, > +}; > + > +ssize_t iio_interrupt_read(struct file *filep, > + char *buf, > + size_t count, > + loff_t *f_ps) > +{ > + struct iio_event_interface *ev_int = filep->private_data; > + struct iio_detected_event_list *el; > + int ret; > + > + mutex_lock(&ev_int->event_list_lock); > + if (list_empty(&ev_int->det_events.list)) { > + if (filep->f_flags & O_NONBLOCK) { > + ret = -EAGAIN; > + goto error_mutex_unlock; > + } > + mutex_unlock(&ev_int->event_list_lock); > + /* Blocking on device; waiting for something to be there */ > + ret = wait_event_interruptible(ev_int->wait, > + !list_empty(&ev_int > + ->det_events.list)); > + if (ret) > + goto error_ret; > + /* Single access device so noone else can get the data */ > + mutex_lock(&ev_int->event_list_lock); > + } > + > + el = list_first_entry(&ev_int->det_events.list, > + struct iio_detected_event_list, > + list); > + > + if (copy_to_user(buf, &(el->ev), > + sizeof(struct iio_event_data))) { > + ret = -EFAULT; > + goto error_mutex_unlock; > + } > + > + list_del(&el->list); > + ev_int->current_events--; > + mutex_unlock(&ev_int->event_list_lock); > + > + spin_lock(el->shared_pointer->lock); > + if (el->shared_pointer) > + (el->shared_pointer->ev_p) = NULL; > + spin_unlock(el->shared_pointer->lock); > + > + kfree(el); > + > + return sizeof(struct iio_event_data); > + > +error_mutex_unlock: > + mutex_unlock(&ev_int->event_list_lock); > +error_ret: > + > + return ret; > +} > + > +int iio_interrupt_release(struct inode *inode, struct file *filep) > +{ > + struct iio_event_interface *ev_int = filep->private_data; > + > + module_put(ev_int->owner); > + clear_bit(IIO_BUSY_BIT_POS, &ev_int->handler.flags); > + > + return 0; > +} > + > +int iio_interrupt_open(struct inode *inode, struct file *filep) > +{ > + struct iio_event_interface *ev_int = filep->private_data; > + > + try_module_get(ev_int->owner); > + > + return 0; > +} > +static const struct file_operations iio_interrupt_fileops = { > + .read = iio_interrupt_read, > + .release = iio_interrupt_release, > + .open = iio_interrupt_open, > + .owner = THIS_MODULE, > +}; > + > + > +ssize_t iio_show_attr_minor(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + int len; > + > + struct iio_chrdev_minor_attr *_attr > + = to_iio_chrdev_minor_attr(attr); > + len = sprintf(buf, "%d\n", _attr->minor); > + > + return len; > +} > + > +void __init_iio_chrdev_minor_attr(struct iio_chrdev_minor_attr *minor_attr, > + const char *name, > + struct module *owner, > + int id) > +{ > + minor_attr->dev_attr.attr.name = name; > + minor_attr->dev_attr.attr.owner = owner; > + minor_attr->dev_attr.attr.mode = S_IRUGO; > + minor_attr->minor = id; > + minor_attr->dev_attr.show = &iio_show_attr_minor; > +} > + > +int iio_setup_ev_int(struct iio_event_interface *ev_int, > + const char *name, > + struct module *owner, > + struct device *dev) > +{ > + int ret; > + > + mutex_init(&ev_int->event_list_lock); > + /* discussion point - make this variable? */ > + ev_int->max_events = 10; > + ev_int->current_events = 0; > + INIT_LIST_HEAD(&ev_int->det_events.list); > + init_waitqueue_head(&ev_int->wait); > + ev_int->handler.fops = &iio_interrupt_fileops; > + ev_int->handler.private = ev_int; > + ev_int->handler.flags = 0; > + ret = iio_allocate_chrdev(&ev_int->handler); > + if (ret) > + goto error_ret; > + __init_iio_chrdev_minor_attr(&ev_int->attr, > + (const char *)(name), > + owner, > + ev_int->handler.id); > + ret = sysfs_create_file(&dev->kobj, &ev_int->attr.dev_attr.attr); > + if (ret) > + goto error_deallocate_chrdev; > + > + return 0; > +error_deallocate_chrdev: > + iio_deallocate_chrdev(&ev_int->handler); > +error_ret: > + return ret; > +} > + > +void iio_free_ev_int(struct iio_event_interface *ev_int, struct device *dev) > +{ > + sysfs_remove_file(&dev->kobj, &ev_int->attr.dev_attr.attr); > + iio_deallocate_chrdev(&ev_int->handler); > +} > + > +static int __init iio_init(void) > +{ > + int ret; > + > + memset(iio_state.fhs, > + sizeof(struct iio_handler *)*256, > + 0); > + > + /* Create sysfs class */ > + ret = class_register(&iio_class); > + if (ret < 0) { > + printk(KERN_ERR > + "industrialio.c: could not create sysfs class\n"); > + goto error_nothing; > + } > + > + ret = register_chrdev(IIO_MAJOR, "industrialio", &iio_fops); > + if (ret) { > + printk(KERN_ERR > + "industrialio: unable to register a char major %d", > + IIO_MAJOR); > + goto error_unregister_class; > + } > + > + return 0; > +error_unregister_class: > + class_unregister(&iio_class); > +error_nothing: > + return ret; > +} > + > +static void __exit iio_exit(void) > +{ > + unregister_chrdev(IIO_MAJOR, "bob"); > + class_unregister(&iio_class); > +} > + > +int iio_device_register_sysfs(struct iio_dev *dev_info) > +{ > + int ret; > + > + dev_info->sysfs_dev = device_create(&iio_class, > + dev_info->dev, > + MKDEV(0, 0), > + IIO_ID_FORMAT, > + dev_info->id); > + > + if (IS_ERR(dev_info->sysfs_dev)) { > + /* what would correct error here be?*/ > + ret = -EINVAL; > + goto error_ret; > + } > + /* register attributes */ > + ret = sysfs_create_group(&dev_info->dev->kobj, dev_info->attrs); > + if (ret) { > + dev_err(dev_info->dev, "Failed to register sysfs hooks\n"); > + goto error_free_sysfs_device; > + } > + > + return 0; > + > +error_free_sysfs_device: > + device_unregister(dev_info->dev); > +error_ret: > + return ret; > +} > + > +void iio_device_unregister_sysfs(struct iio_dev *dev_info) > +{ > + sysfs_remove_group(&dev_info->dev->kobj, dev_info->attrs); > + device_unregister(dev_info->sysfs_dev); > +} > + > +int iio_device_register_id(struct iio_dev *dev_info) > +{ > + int ret; > + > +idr_again: > + if (unlikely(idr_pre_get(&iio_idr, GFP_KERNEL) == 0)) > + return -ENOMEM; > + > + spin_lock(&iio_idr_lock); > + ret = idr_get_new(&iio_idr, NULL, &dev_info->id); > + spin_unlock(&iio_idr_lock); > + if (unlikely(ret == -EAGAIN)) > + goto idr_again; > + else if (unlikely(ret)) > + return ret; > + dev_info->id = dev_info->id & MAX_ID_MASK; > + > + return 0; > +} > +void iio_device_unregister_id(struct iio_dev *dev_info) > +{ > + /* Can I use the save id? */ > + int id; > + > + if (likely(sscanf(dev_info->sysfs_dev->bus_id, > + IIO_ID_FORMAT, &id) == 1)) { > + spin_lock(&iio_idr_lock); > + idr_remove(&iio_idr, id); > + spin_unlock(&iio_idr_lock); > + } else > + dev_dbg(dev_info->dev->parent, > + "indio_device_unregister() failed: bad class ID!\n"); > +} > + > +int iio_device_register_eventset(struct iio_dev *dev_info) > +{ > + int ret, i, j; > + > + struct device_attribute *devattr; > + struct iio_event_attr *indio_devattr; > + > + if (dev_info->num_interrupt_lines == 0) > + return 0; > + dev_info->event_interfaces = (struct iio_event_interface *) > + (kzalloc(sizeof(struct iio_event_interface) > + *dev_info->num_interrupt_lines, > + GFP_KERNEL)); > + if (dev_info->event_interfaces == NULL) { > + ret = -ENOMEM; > + goto error_ret; > + } > + /* assign id's to the event_interface elements */ > + for (i = 0; i < dev_info->num_interrupt_lines; i++) { > + dev_info->event_interfaces[i].id = i; > + dev_info->event_interfaces[i].owner = dev_info->driver_module; > + } > + dev_info->interrupts > + = kzalloc(sizeof(struct iio_interrupt *) > + *dev_info->num_interrupt_lines, > + GFP_KERNEL); > + if (dev_info->interrupts == NULL) { > + dev_err(dev_info->dev, > + "Failed to register sysfs hooks for events attributes"); > + ret = -ENOMEM; > + goto error_free_event_interfaces; > + } > + > + for (i = 0; i < dev_info->num_interrupt_lines; i++) { > + > + snprintf(dev_info->event_interfaces[i]._name, 20, > + "event_line%d_minor", i); > + ret = iio_setup_ev_int(&dev_info->event_interfaces[i], > + (const char *)(dev_info > + ->event_interfaces[i] > + ._name), > + dev_info->driver_module, > + dev_info->dev); > + if (ret) { > + dev_err(dev_info->dev, > + "Could not get chrdev interface\n"); > + goto error_free_setup_ev_ints; > + } > + } > + dev_info->event_attrs->name = "event_sources"; > + ret = sysfs_create_group(&dev_info->dev->kobj, dev_info->event_attrs); > + if (ret) { > + dev_err(dev_info->dev, > + "Failed to register sysfs hooks for events attributes"); > + goto error_free_setup_ev_ints; > + } > + /* May double initialize lists in case of shared handlers, > + but other than a slight overhead that isn't a problem */ > + j = 0; > + while (1) { > + if (dev_info->event_attrs->attrs[j] == NULL) > + break; > + devattr = container_of(dev_info->event_attrs->attrs[j], > + struct device_attribute, attr); > + indio_devattr = to_iio_event_attr(devattr); > + INIT_LIST_HEAD(&indio_devattr->listel->list); > + j++; > + } > + return 0; > + > +error_free_setup_ev_ints: > + for (j = 0; j < i; j++) > + iio_free_ev_int(&dev_info->event_interfaces[j], > + dev_info->dev); > + kfree(dev_info->interrupts); > +error_free_event_interfaces: > + kfree(dev_info->event_interfaces); > +error_ret: > + return ret; > +} > + > +void iio_device_unregister_eventset(struct iio_dev *dev_info) > +{ > + int i; > + if (dev_info->num_interrupt_lines == 0) > + return; > + for (i = 0; i < dev_info->num_interrupt_lines; i++) > + iio_free_ev_int(&dev_info->event_interfaces[i], > + dev_info->dev); > + if (dev_info->event_attrs) > + sysfs_remove_group(&dev_info->dev->kobj, dev_info->event_attrs); > + kfree(dev_info->event_interfaces); > +} > + > +int iio_get_ptimer(const char **name) > +{ > + struct ptimer_info_listel *ptimer_i; > + > + *name = NULL; > + mutex_lock(&industrialio_ptimer_board_lock); > + > + list_for_each_entry(ptimer_i, &industrialio_ptimer_board_info_list, > + list) > + if (ptimer_i->inuse == false) { > + ptimer_i->inuse = true; > + *name = ptimer_i->info.name; > + break; > + } > + mutex_unlock(&industrialio_ptimer_board_lock); > + if (*name == NULL) > + return -EINVAL; > + > + return 0; > +} > +int iio_free_ptimer(const char *name) > +{ > + struct ptimer_info_listel *ptimer_i; > + > + mutex_lock(&industrialio_ptimer_board_lock); > + list_for_each_entry(ptimer_i, &industrialio_ptimer_board_info_list, > + list) > + if (ptimer_i->info.name == name) { > + ptimer_i->inuse = false; > + break; > + } > + mutex_unlock(&industrialio_ptimer_board_lock); > + > + return 0; > +} > + > +int iio_device_register_ptimer(struct iio_dev *dev_info) > +{ > + int ret = 0; > + > + if (dev_info->modes & INDIO_RING_POLLED) { > + ret = iio_get_ptimer(&dev_info->ptimer_name); > + if (ret) > + goto error_ret; > + ret = iio_ptimer_request_periodic_timer((char *) > + (dev_info->ptimer_name), > + dev_info); > + if (ret) > + goto error_release_ptimer; > + } > + > + return ret; > + > +error_release_ptimer: > + iio_free_ptimer(dev_info->ptimer_name); > +error_ret: > + return ret; > + > +} > + > +void iio_device_unregister_ptimer(struct iio_dev *dev_info) > +{ > + if (dev_info->ptimer) { > + iio_ptimer_unrequest_periodic_timer(dev_info); > + iio_free_ptimer(dev_info->ptimer_name); > + } > +} > + > +int iio_device_register(struct iio_dev *dev_info) > +{ > + int ret; > + mutex_init(&dev_info->mlock); > + dev_set_drvdata(dev_info->dev, (void *)(dev_info)); > + > +/*Get a unique id */ > + ret = iio_device_register_id(dev_info); > + if (ret) > + goto error_nothing; > + > +/* Create sysfs device */ > + ret = iio_device_register_sysfs(dev_info); > + if (ret) > + goto error_free_idr; > + > +/* Interrupt triggered events setup */ > + ret = iio_device_register_eventset(dev_info); > + if (ret) > + goto error_free_sysfs; > + > +/* Ring buffer init if relevant */ > + if (dev_info->modes & (INDIO_RING_POLLED | INDIO_RING_DATA_RDY)) { > + > + ret = iio_device_register_sw_ring(dev_info, 0); > + if (ret) > + goto error_free_eventset; > + } > +/* Register ptimer if relevant */ > + if (dev_info->modes & INDIO_RING_POLLED) { > + ret = iio_device_register_ptimer(dev_info); > + if (ret) > + goto error_unregister_sw_ring; > + } > + > + return 0; > + > +error_unregister_sw_ring: > + iio_device_unregister_sw_ring(dev_info); > +error_free_eventset: > + iio_device_unregister_eventset(dev_info); > +error_free_sysfs: > + iio_device_unregister_sysfs(dev_info); > +error_free_idr: > + iio_device_unregister_id(dev_info); > +error_nothing: > + > + return ret; > +} > +EXPORT_SYMBOL_GPL(iio_device_register); > + > +void iio_device_unregister(struct iio_dev *dev_info) > +{ > + if (dev_info->modes & INDIO_RING_POLLED) > + iio_device_unregister_ptimer(dev_info); > + if (dev_info->modes & (INDIO_RING_POLLED | INDIO_RING_DATA_RDY)) > + iio_device_unregister_sw_ring(dev_info); > + iio_device_unregister_eventset(dev_info); > + iio_device_unregister_sysfs(dev_info); > + iio_device_unregister_id(dev_info); > + > +} > +EXPORT_SYMBOL_GPL(iio_device_unregister); > + > +subsys_initcall(iio_init); > +module_exit(iio_exit); > --- a/drivers/industrialio/industrialio-rtc.c 1970-01-01 01:00:00.000000000 +0100 > +++ b/drivers/industrialio/industrialio-rtc.c 2008-07-23 15:08:43.000000000 +0100 > @@ -0,0 +1,134 @@ > +/* 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. > + */ > +#include > +#include > +#include > +#include > +#include > +/* This is a temporary stop gap until a more generic timer subsystem is in place > + * within the kernel. > + * See discussion (initial thoughts so far) on the rtc mailing list. > + * Comments still welcomed though I may not do much about them!. > + */ > +int iio_ptimer_irq_set_state(struct iio_dev *indio_dev, bool state) > +{ > + return rtc_irq_set_state(indio_dev->ptimer->rtc, > + &indio_dev->ptimer->task, > + state); > +} > +EXPORT_SYMBOL(iio_ptimer_irq_set_state); > + > +int iio_ptimer_set_freq(struct iio_periodic *ptimer, > + unsigned frequency) > +{ > + int ret; > + > + ret = rtc_irq_set_freq(ptimer->rtc, &ptimer->task, frequency); > + if (ret == 0) > + ptimer->frequency = frequency; > + > + return ret; > +} > +EXPORT_SYMBOL(iio_ptimer_set_freq); > + > +static ssize_t iio_ptimer_show_samp_freq(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + struct iio_dev *dev_info = dev_get_drvdata(dev); > + struct iio_periodic *ptimer = dev_info->ptimer; > + return sprintf(buf, "%u\n", ptimer->frequency); > +} > + > +static ssize_t iio_ptimer_store_samp_freq(struct device *dev, > + struct device_attribute *attr, > + const char *buf, > + size_t len) > +{ > + struct iio_dev *dev_info = dev_get_drvdata(dev); > + struct iio_periodic *ptimer = dev_info->ptimer; > + int ret; > + unsigned long val; > + > + ret = strict_strtoul(buf, 10, &val); > + if (ret) > + goto error_ret; > + ret = iio_ptimer_set_freq(ptimer, val); > + if (ret) > + goto error_ret; > + return len; > + > +error_ret: > + return ret; > +} > + > + > +IIO_DEV_ATTR_SAMP_FREQ(S_IRUGO | S_IWUSR, > + iio_ptimer_show_samp_freq, > + iio_ptimer_store_samp_freq); > + > +int iio_ptimer_request_periodic_timer(char *name, > + struct iio_dev *indio_dev) > +{ > + int ret; > + > + indio_dev->ptimer = kmalloc(sizeof(struct iio_periodic), GFP_KERNEL); > + indio_dev->ptimer->rtc = rtc_class_open(name); > + if (indio_dev->ptimer == NULL) { > + ret = -EINVAL; > + goto error_free_ptimer; > + } > + indio_dev->ptimer->task.func = indio_dev->ring_poll_func; > + indio_dev->ptimer->task.private_data = indio_dev; > + ret = rtc_irq_register(indio_dev->ptimer->rtc, > + &indio_dev->ptimer->task); > + if (ret) > + goto error_close_class; > + > + ret = sysfs_add_file_to_group(&indio_dev->dev->kobj, > + &iio_dev_attr_sampling_frequency > + .dev_attr.attr, > + "ring_buffer"); > + if (ret) > + goto error_unregister_irq; > + > + return 0; > + > +error_unregister_irq: > + rtc_irq_unregister(indio_dev->ptimer->rtc, &indio_dev->ptimer->task); > + > +error_close_class: > + rtc_class_close(indio_dev->ptimer->rtc); > +error_free_ptimer: > + kfree(indio_dev->ptimer); > + indio_dev->ptimer = NULL; > + return ret; > +} > +EXPORT_SYMBOL(iio_ptimer_request_periodic_timer); > + > +void iio_ptimer_unrequest_periodic_timer(struct iio_dev *indio_dev) > +{ > + > + sysfs_remove_file_from_group(&indio_dev->dev->kobj, > + &iio_dev_attr_sampling_frequency > + .dev_attr.attr, > + "ring_buffer"); > + > + if (indio_dev->ptimer->rtc) { > + rtc_irq_set_state(indio_dev->ptimer->rtc, > + &indio_dev->ptimer->task, 0); > + rtc_irq_unregister(indio_dev->ptimer->rtc, > + &indio_dev->ptimer->task); > + flush_scheduled_work(); > + rtc_class_close(indio_dev->ptimer->rtc); > + flush_scheduled_work(); > + } > + kfree(indio_dev->ptimer); > +} > +EXPORT_SYMBOL(iio_ptimer_unrequest_periodic_timer); > --- a/drivers/industrialio/industrialio-ring.c 1970-01-01 01:00:00.000000000 +0100 > +++ b/drivers/industrialio/industrialio-ring.c 2008-07-23 15:10:39.000000000 +0100 > @@ -0,0 +1,770 @@ > +/* 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. > + * > + * Handling of ring allocation / resizing. > + * > + * > + * Things to look at here. > + * - Better memory allocation techniques? > + * - Alternative access techniques? > + */ > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* Prevent resizing of the ring if it might break anything */ > +void iio_mark_sw_ring_buffer_in_use(struct iio_sw_ring_buffer *ring) > +{ > + spin_lock(ring->use_lock); > + ring->use_count++; > + spin_unlock(ring->use_lock); > +} > +EXPORT_SYMBOL_GPL(iio_mark_sw_ring_buffer_in_use); > + > +void iio_unmark_sw_ring_buffer_in_use(struct iio_sw_ring_buffer *ring) > +{ > + spin_lock(ring->use_lock); > + ring->use_count--; > + spin_unlock(ring->use_lock); > +} > +EXPORT_SYMBOL_GPL(iio_unmark_sw_ring_buffer_in_use); > + > +/* Mark that a resize is needed */ > +static void iio_mark_sw_ring_buffer_need_update(struct iio_sw_ring_buffer *ring) > +{ > + spin_lock(ring->use_lock); > + ring->update_needed = 1; > + spin_unlock(ring->use_lock); > +} > + > +/* Event handling for the ring - allows escallation of events */ > +int iio_put_ring_event(struct iio_ring_buffer *ring_buf, > + int event_code, > + s64 timestamp) > +{ > + return __iio_put_event(&ring_buf->ev_int, > + event_code, > + timestamp, > + &ring_buf->shared_ev_pointer); > +} > +EXPORT_SYMBOL(iio_put_ring_event); > + > +int iio_put_or_escallate_ring_event(struct iio_ring_buffer *ring_buf, > + int event_code, > + s64 timestamp) > +{ > + if (ring_buf->shared_ev_pointer.ev_p) > + __iio_change_event(ring_buf->shared_ev_pointer.ev_p, > + event_code, > + timestamp); > + else > + return iio_put_ring_event(ring_buf, > + event_code, > + timestamp); > + return 0; > +} > +EXPORT_SYMBOL(iio_put_or_escallate_ring_event); > + > + > +/* Ring buffer related functionality */ > +/* Store to ring is typically called in the bh of a data ready interrupt handler > + * in the device driver */ > +/* Lock always held if their is a chance this may be called */ > +int iio_store_to_sw_ring(struct iio_sw_ring_buffer *ring, > + unsigned char *data, > + s64 timestamp) > +{ > + bool init_read = true; > + int ret; > + int code; > + > + /* initial store */ > + if (unlikely(ring->write_p == 0)) { > + ring->write_p = ring->data; > + /* doesn't actually matter if this is out of the set */ > + ring->half_p = ring->data - ring->buf.length*ring->buf.size/2; > + init_read = false; > + } > + memcpy(ring->write_p, data, ring->buf.size); > + barrier(); > + ring->last_written_p = ring->write_p; > + barrier(); > + ring->write_p += ring->buf.size; > + /* End of ring, back to the beginning */ > + if (ring->write_p == ring->data + ring->buf.length*ring->buf.size) { > + ring->write_p = ring->data; > + ring->buf.loopcount++; > + } > + if (ring->read_p == 0) > + ring->read_p = ring->data; > + /* Buffer full - move the read pointer and create / escalate > + * ring event */ > + else if (ring->write_p == ring->read_p) { > + ring->read_p += ring->buf.size; > + if (ring->read_p > + == ring->data + ring->buf.length*ring->buf.size) > + ring->read_p = ring->data; > + > + spin_lock(ring->buf.shared_ev_pointer.lock); > + if (ring->buf.shared_ev_pointer.ev_p) { > + /* Event escalation - probably quicker to let this > + keep running than check if it is necessary */ > + code = IIO_EVENT_CODE_RING_100_FULL; > + __iio_change_event(ring > + ->buf.shared_ev_pointer.ev_p, > + code, > + timestamp); > + } else { > + code = IIO_EVENT_CODE_RING_100_FULL; > + ret = __iio_put_event(&ring->buf.ev_int, > + code, > + timestamp, > + &ring > + ->buf.shared_ev_pointer); > + if (ret) { > + spin_unlock(ring->buf.shared_ev_pointer.lock); > + goto error_ret; > + } > + } > + spin_unlock(ring->buf.shared_ev_pointer.lock); > + } > + /* investigate if our event barrier has been passed */ > + /* There are definite 'issues' with this and chances of > + * simultaneous read */ > + /* Also need to use loop count to ensure this only happens once */ > + ring->half_p += ring->buf.size; > + if (ring->half_p == ring->data + ring->buf.length*ring->buf.size) > + ring->half_p = ring->data; > + if (ring->half_p == ring->read_p) { > + spin_lock(ring->buf.shared_ev_pointer.lock); > + code = IIO_EVENT_CODE_RING_50_FULL; > + ret = __iio_put_event(&ring->buf.ev_int, > + code, > + timestamp, > + &ring->buf.shared_ev_pointer); > + spin_unlock(ring->buf.shared_ev_pointer.lock); > + > + if (ret) > + goto error_ret; > + } > + return 0; > +error_ret: > + return ret; > +} > +EXPORT_SYMBOL_GPL(iio_store_to_sw_ring); > + > + > +/*doesn't currently read the timestamp */ > +/* For software ring buffers this function is needed to get the latest > + * reading without preventing it from ending up in the ring buffer. > +*/ > +int iio_read_last_from_sw_ring(struct iio_sw_ring_buffer *ring, > + unsigned char *data) > +{ > + int loopcount_copy; > + unsigned char *last_written_p_copy; > + iio_mark_sw_ring_buffer_in_use(ring); > +again: > + loopcount_copy = ring->buf.loopcount; > + barrier(); > + last_written_p_copy = ring->last_written_p; > + barrier(); /*unnessecary? */ > + > + memcpy(data, last_written_p_copy, ring->buf.size); > + > + if (unlikely(loopcount_copy != ring->buf.loopcount)) { > + if (unlikely(ring->last_written_p >= last_written_p_copy)) > + goto again; > + } > + iio_unmark_sw_ring_buffer_in_use(ring); > + return 0; > +} > +EXPORT_SYMBOL_GPL(iio_read_last_from_sw_ring); > + > +/* Ring buffer access fileops */ > +int iio_ring_open(struct inode *inode, struct file *filp) > +{ > + struct iio_sw_ring_buffer *ring = filp->private_data; > + > + iio_mark_sw_ring_buffer_in_use(ring); > + try_module_get(ring->buf.access_minor_attr.dev_attr.attr.owner); > + > + return 0; > +} > + > +int iio_ring_release(struct inode *inode, struct file *filp) > +{ > + struct iio_sw_ring_buffer *ring = filp->private_data; > + > + module_put(ring->buf.access_minor_attr.dev_attr.attr.owner); > + clear_bit(IIO_BUSY_BIT_POS, &ring->buf.access_handler.flags); > + iio_unmark_sw_ring_buffer_in_use(ring); > + > + return 0; > +} > + > +/* no point in ripping more than nearest number of whole records below count */ > +/* Depending on movement of pointers in the meantime this may return a lot > + * less than count*/ > +/* Also, we aren't going to wait for enough data to be available */ > + > +/* Can only occur currently when the ring buffer is marked > + - from userspace call */ > +ssize_t iio_ring_rip(struct file *filp, > + char *buf, > + size_t count, > + loff_t *f_ps) > +{ > + unsigned char *initial_read_p, *initial_write_p, > + *current_read_p, *end_read_p; > + > + struct iio_sw_ring_buffer *ring = filp->private_data; > + unsigned char *data_cpy; > + int ret; > + int dead_offset; > + int bytes_to_rip = 0; > + int max_copied; > + /* Round down to nearest datum boundary */ > + bytes_to_rip = (count - count % ring->buf.size); > + /* Limit size to whole of ring buffer */ > + if (bytes_to_rip > ring->buf.size*ring->buf.length) > + bytes_to_rip = ring->buf.size*ring->buf.length; > + data_cpy = kmalloc(bytes_to_rip, GFP_KERNEL); > + if (data_cpy == NULL) { > + ret = -ENOMEM; > + goto error_ret; > + } > + > + /* build local copy */ > + initial_read_p = ring->read_p; > + if (unlikely(initial_read_p == 0)) { > + /* No data here as yet */ > + ret = 0; > + goto error_free_data_cpy; > + } > + initial_write_p = ring->write_p; > + > + /* Need a consistent pair */ > + while (initial_read_p != ring->read_p > + || initial_write_p != ring->write_p) { > + initial_read_p = ring->read_p; > + initial_write_p = ring->write_p; > + } > + if (initial_write_p == initial_read_p) { > + /* No new data available.*/ > + ret = 0; > + goto error_free_data_cpy; > + } > + > + if (initial_write_p > initial_read_p + bytes_to_rip) { > + /* write_p is greater than necessary, all is easy */ > + max_copied = bytes_to_rip; > + memcpy(data_cpy, initial_read_p, max_copied); > + end_read_p = initial_read_p + max_copied; > + } else if (initial_write_p > initial_read_p) { > + /*not enough data to cpy */ > + max_copied = initial_write_p - initial_read_p; > + memcpy(data_cpy, initial_read_p, max_copied); > + end_read_p = initial_write_p; > + } else { /* going through 'end' of ring buffer */ > + max_copied = ring->data > + + ring->buf.length*ring->buf.size - initial_read_p; > + memcpy(data_cpy, initial_read_p, max_copied); > + if (initial_write_p > ring->data + bytes_to_rip - max_copied) { > + /* enough data to finish */ > + memcpy(data_cpy + max_copied, ring->data, > + bytes_to_rip - max_copied); > + max_copied = bytes_to_rip; > + end_read_p = ring->data + (bytes_to_rip - max_copied); > + } else { /* not enough data */ > + memcpy(data_cpy + max_copied, ring->data, > + initial_write_p - ring->data); > + max_copied += initial_write_p - ring->data; > + end_read_p = initial_write_p; > + } > + } > + /* Now to verify which section was cleanly copied - i.e. how far > + * read pointer has been pushed */ > + current_read_p = ring->read_p; > + > + if (initial_read_p <= current_read_p) > + dead_offset = current_read_p - initial_read_p; > + else > + dead_offset = ring->buf.length*ring->buf.size > + - (initial_read_p - current_read_p); > + > + /* possible issue if the initial write has been lapped or indeed > + * the point we were reading to has been passed */ > + /* No valid data read. > + * In this case the read pointer is already correct having been > + * pushed further than we would look. */ > + if (max_copied - dead_offset < 0) { > + ret = 0; > + goto error_free_data_cpy; > + } > + > + /* setup the next read position */ > + ring->read_p = end_read_p; > + > + if (copy_to_user(buf, data_cpy + dead_offset, > + max_copied - dead_offset)) { > + ret = -EFAULT; > + goto error_free_data_cpy; > + } > + kfree(data_cpy); > + > + return max_copied - dead_offset; > + > +error_free_data_cpy: > + kfree(data_cpy); > +error_ret: > + return 0; > +} > + > +static const struct file_operations iio_ring_fileops = { > + .read = iio_ring_rip, > + .release = iio_ring_release, > + .open = iio_ring_open, > + .owner = THIS_MODULE, > +}; > + > +inline int __iio_request_ring_buffer_event_chrdev(struct iio_ring_buffer *buf, > + int id, > + struct module *owner, > + struct device *dev) > +{ > + int ret; > + > +/* Create and register the event character device */ > + buf->event_minor_name = kmalloc(20, GFP_KERNEL); > + if (buf->event_minor_name == NULL) { > + ret = -ENOMEM; > + goto error_ret; > + } > + sprintf(buf->event_minor_name, "ring_buffer%d_ev_minor", id); > + ret = iio_setup_ev_int(&(buf->ev_int), > + (const char *)(buf->event_minor_name), > + owner, > + dev); > + if (ret) > + goto error_free_event_minor_name; > + > + return 0; > + > +error_free_event_minor_name: > + kfree(buf->event_minor_name); > +error_ret: > + return ret; > +} > + > +inline void __iio_free_ring_buffer_event_chrdev(struct iio_ring_buffer *buf, > + struct device *dev) > +{ > + iio_free_ev_int(&(buf->ev_int), dev); > + kfree(buf->event_minor_name); > +} > + > +inline int > +__iio_request_ring_buffer_access_chrdev(struct iio_ring_buffer *buf, > + int id, > + struct module *owner, > + struct device *dev, > + const struct file_operations *fops) > +{ > + int ret; > +/* Create and register the access character device */ > + buf->access_minor_name = kmalloc(20, GFP_KERNEL); > + if (buf->access_minor_name == NULL) { > + ret = -ENOMEM; > + goto error_ret; > + } > + sprintf(buf->access_minor_name, "ring_buffer%d_access_minor", id); > + > + ret = iio_allocate_chrdev(&buf->access_handler); > + if (ret) > + goto error_free_access_minor_name; > + buf->access_handler.fops = fops; > + buf->access_handler.flags = 0; > + > + __init_iio_chrdev_minor_attr(&buf->access_minor_attr, > + (const char *)(buf->access_minor_name), > + owner, > + buf->access_handler.id); > + > + ret = sysfs_create_file(&dev->kobj, > + &(buf->access_minor_attr.dev_attr.attr)); > + if (ret) > + goto error_deallocate_chrdev; > + return 0; > + > +error_deallocate_chrdev: > + iio_deallocate_chrdev(&buf->access_handler); > +error_free_access_minor_name: > + kfree(buf->access_minor_name); > +error_ret: > + return ret; > +} > + > +inline void __iio_free_ring_buffer_access_chrdev(struct iio_ring_buffer *buf, > + struct device *dev) > +{ > + sysfs_remove_file(&dev->kobj, > + &buf->access_minor_attr.dev_attr.attr); > + iio_deallocate_chrdev(&buf->access_handler); > + kfree(buf->access_minor_name); > +} > + > +int iio_request_hw_ring_buffer(int bytes_per_datum, > + int length, > + struct iio_hw_ring_buffer **ring, > + int id, > + struct module *owner, > + struct device *dev, > + const struct file_operations *fops, > + void *private) > +{ > + int ret; > + > + *ring = kmalloc(sizeof(struct iio_hw_ring_buffer), > + GFP_KERNEL); > + > + if (*ring == NULL) { > + ret = -ENOMEM; > + goto error_ret; > + } > + (*ring)->private = private; > + INIT_IIO_RING_BUFFER(&((*ring)->buf), bytes_per_datum, length); > + ret = __iio_request_ring_buffer_event_chrdev(&(*ring)->buf, > + id, > + owner, > + dev); > + > + if (ret) > + goto error_free_ring_data; > + ret = __iio_request_ring_buffer_access_chrdev(&(*ring)->buf, > + id, > + owner, > + dev, > + fops); > + if (ret) > + goto error_free_ring_buffer_event_chrdev; > + (*ring)->buf.ev_int.private = (*ring); > + (*ring)->buf.access_handler.private = (*ring); > + > + return 0; > + > +error_free_ring_buffer_event_chrdev: > + __iio_free_ring_buffer_event_chrdev(&(*ring)->buf, dev); > +error_free_ring_data: > + /* there isn't any!*/ > +error_ret: > + return ret; > +} > +EXPORT_SYMBOL_GPL(iio_request_hw_ring_buffer); > + > +void iio_free_hw_ring_buffer(struct iio_hw_ring_buffer *ring, > + struct device *dev) > +{ > + __iio_free_ring_buffer_access_chrdev(&(ring->buf), dev); > + __iio_free_ring_buffer_event_chrdev(&(ring->buf), dev); > + kfree(ring); > +} > +EXPORT_SYMBOL_GPL(iio_free_hw_ring_buffer); > + > + > +/* Resize the ring if requested - run whenever ring buffer mode entered */ > +int __iio_request_update_sw_ring_buffer(int bytes_per_datum, > + int length, > + struct iio_sw_ring_buffer *ring, > + int id, > + struct module *owner, > + struct device *dev) > +{ > +/* Reference count the ring - if anyone is using it this will fail!*/ > + int ret = 0; > +/* Need to sanity check if this is necessary? */ > + spin_lock(ring->use_lock); > + > + if (ring->use_count || !ring->update_needed) { > + ret = -EAGAIN; > + goto error_ret; > + } > + kfree(ring->data); > + /* keeps clear of chr devs etc - so fine to use here - I THINK!*/ > + INIT_IIO_SW_RING_BUFFER(ring, bytes_per_datum, length); > + if (ring->data == NULL) > + ret = -ENOMEM; > + > +error_ret: > + spin_unlock(ring->use_lock); > + return ret; > +} > + > +int iio_request_update_sw_ring_buffer(struct iio_dev *dev_info, int id) > +{ > + return __iio_request_update_sw_ring_buffer(dev_info > + ->ring_bytes_per_datum, > + dev_info->ring_length, > + dev_info->ring, > + id, > + dev_info->driver_module, > + dev_info->dev); > +} > +EXPORT_SYMBOL_GPL(iio_request_update_sw_ring_buffer); > + > +/* Should only occur on init so no locking needed */ > +int iio_request_sw_ring_buffer(int bytes_per_datum, > + int length, > + struct iio_sw_ring_buffer **ring, > + int id, > + struct module *owner, > + struct device *dev) > +{ > + int ret; > + > + /* Actually do the ring buffer initialization */ > + *ring = kzalloc(sizeof(struct iio_sw_ring_buffer), > + GFP_KERNEL); > + if (*ring == NULL) { > + ret = -ENOMEM; > + goto error_ret; > + } > + /* Moved to an allocation on demand model.*/ > + iio_mark_sw_ring_buffer_need_update(*ring); > + ret = __iio_request_ring_buffer_event_chrdev(&(*ring)->buf, > + id, > + owner, > + dev); > + if (ret) > + goto error_free_ring_data; > + > + ret = __iio_request_ring_buffer_access_chrdev(&(*ring)->buf, > + id, > + owner, > + dev, > + &iio_ring_fileops); > + if (ret) > + goto error_free_ring_buffer_event_chrdev; > + > + /* Setup the private pointer so the fileoperations will work */ > + (*ring)->buf.ev_int.private = (*ring); > + (*ring)->buf.access_handler.private = (*ring); > + > + return 0; > + > +error_free_ring_buffer_event_chrdev: > + __iio_free_ring_buffer_event_chrdev(&(*ring)->buf, dev); > +error_free_ring_data: > + FREE_IIO_SW_RING_BUFFER(*ring); > + kfree(*ring); > +error_ret: > + return ret; > +} > +EXPORT_SYMBOL_GPL(iio_request_sw_ring_buffer); > + > +void iio_free_sw_ring_buffer(struct iio_sw_ring_buffer *ring, > + struct device *dev) > +{ > + __iio_free_ring_buffer_access_chrdev(&(ring->buf), dev); > + __iio_free_ring_buffer_event_chrdev(&(ring->buf), dev); > + FREE_IIO_SW_RING_BUFFER(ring); > + kfree(ring); > +} > +EXPORT_SYMBOL_GPL(iio_free_sw_ring_buffer); > + > +static ssize_t iio_read_ring_length(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + int len; > + struct iio_dev *dev_info = dev_get_drvdata(dev); > + > + len = sprintf(buf, "%d\n", dev_info->ring_length); > + > + return len; > +} > + > +static ssize_t iio_write_ring_length(struct device *dev, > + struct device_attribute *attr, > + const char *buf, > + size_t len) > +{ > + int ret; > + long val; > + struct iio_dev *dev_info = dev_get_drvdata(dev); > + ret = strict_strtol(buf, 10, &val); > + if (ret) > + goto error_ret; > + /* Ring length stored here and in ring? */ > + if (val != dev_info->ring_length) { > + dev_info->ring_length = val; > + iio_mark_sw_ring_buffer_need_update(dev_info->ring); > + } > + > + return len; > +error_ret: > + return ret; > +} > + > +static ssize_t iio_read_ring_bps(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + int len; > + struct iio_dev *dev_info = dev_get_drvdata(dev); > + > + len = sprintf(buf, "%d\n", dev_info->ring_bytes_per_datum); > + > + return len; > +} > + > + > +DEVICE_ATTR(length, S_IRUGO | S_IWUSR, > + iio_read_ring_length, > + iio_write_ring_length); > +/* The software ring buffers aren't currently capable of changing the > + * storage accuracy so this is read only. > + */ > +DEVICE_ATTR(bps, S_IRUGO, > + iio_read_ring_bps, > + NULL); > + > +ssize_t iio_store_ring_enable(struct device *dev, > + struct device_attribute *attr, > + const char *buf, > + size_t len) > +{ > + int ret; > + bool requested_state, current_state; > + struct iio_dev *dev_info = dev_get_drvdata(dev); > + > + mutex_lock(&dev_info->mlock); > + requested_state = (buf[0] == '0') ? 0 : 1; > + current_state = (dev_info->currentmode > + & (INDIO_RING_DATA_RDY | INDIO_RING_POLLED)) > + ? 1: 0; > + if (current_state == requested_state) > + goto done; > + if (requested_state) { > + if (dev_info->ring_preenable) { > + ret = dev_info->ring_preenable(dev_info); > + if (ret) > + goto error_ret; > + } > + ret = iio_request_update_sw_ring_buffer(dev_info, 0); > + if (ret) > + goto error_ret; > + iio_mark_sw_ring_buffer_in_use(dev_info->ring); > + if (dev_info->modes & INDIO_RING_DATA_RDY) > + dev_info->currentmode = INDIO_RING_DATA_RDY; > + else if (dev_info->modes & INDIO_RING_POLLED) > + dev_info->currentmode = INDIO_RING_POLLED; > + else { /* should never be reached */ > + ret = -EINVAL; > + goto error_ret; > + } > + > + if (dev_info->ring_postenable) { > + ret = dev_info->ring_postenable(dev_info); > + if (ret) > + goto error_ret; > + } > + } else { > + if (dev_info->ring_predisable) { > + ret = dev_info->ring_predisable(dev_info); > + if (ret) > + goto error_ret; > + } > + iio_unmark_sw_ring_buffer_in_use(dev_info->ring); > + dev_info->currentmode = INDIO_DIRECT_MODE; > + if (dev_info->ring_postdisable) { > + ret = dev_info->ring_postdisable(dev_info); > + if (ret) > + goto error_ret; > + } > + } > +done: > + mutex_unlock(&dev_info->mlock); > + return len; > +error_ret: > + mutex_unlock(&dev_info->mlock); > + return ret; > +} > + > +static ssize_t iio_show_ring_enable(struct device *dev, > + struct device_attribute *attr, > + char *buf) > +{ > + > + int len; > + struct iio_dev *indio_dev = dev_get_drvdata(dev); > + > + if (indio_dev->currentmode & (INDIO_RING_DATA_RDY | INDIO_RING_POLLED)) > + len = sprintf(buf, "1\n"); > + else > + len = sprintf(buf, "0\n"); > + > + return len; > +} > + > +DEVICE_ATTR(sw_ring_enable, S_IRUGO | S_IWUSR, > + iio_show_ring_enable, > + iio_store_ring_enable); > + > +static struct attribute *iio_ring_attributes[] = { > + &dev_attr_length.attr, > + &dev_attr_bps.attr, > + &dev_attr_sw_ring_enable.attr, > + NULL, > +}; > + > +static const struct attribute_group iio_ring_attribute_group = { > + .name = "ring_buffer", > + .attrs = iio_ring_attributes, > +}; > + > +int iio_device_register_sw_ring(struct iio_dev *dev_info, int id) > +{ > + int ret; > + > + ret = iio_request_sw_ring_buffer(dev_info->ring_bytes_per_datum, > + dev_info->ring_length, > + &dev_info->ring, > + id, > + dev_info->driver_module, > + dev_info->dev); > + if (ret < 0) > + goto error_ret; > + > + ret = sysfs_create_group(&dev_info->dev->kobj, > + &iio_ring_attribute_group); > + if (ret) > + goto error_free_ring; > + > + return 0; > + > +error_free_ring: > + iio_free_sw_ring_buffer(dev_info->ring, dev_info->dev); > +error_ret: > + return ret; > +} > + > +void iio_device_unregister_sw_ring(struct iio_dev *dev_info) > +{ > + sysfs_remove_group(&dev_info->dev->kobj, > + &iio_ring_attribute_group); > + /* deallocate ring buffer related stuff */ > + if (dev_info->modes & (INDIO_RING_POLLED | INDIO_RING_DATA_RDY)) > + iio_free_sw_ring_buffer(dev_info->ring, dev_info->dev); > + > +} Nice idea, I just don't get what is actually going on in here. This needs more planning. -- Ben Q: What's a light-year? A: One-third less calories than a regular year. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/