Date:	Mon, 10 Aug 2009 14:13:40 +0100
From:	Martyn Welch <martyn.welch@...anuc.com>
To:	"Emilio G. Cota" <cota@...ap.org>
CC:	Greg K-H <gregkh@...e.de>, linux-kernel@...r.kernel.org,
	devel@...uxdriverproject.org,
	Sebastien Dugue <sebastien.dugue@...l.net>
Subject: Re: [patch 2/5] Staging: vme: add VME userspace driver

Emilio G. Cota wrote:
> (oops, just correcting Sebastien's e-mail address)
>
> Emilio G. Cota wrote:
>   
>> I remember we had a look at the vmelinux interface, but it really
>> was so limited that we decided to get rid of it altogether. Do you
>> really think it's worth bringing it back to life? Since it's never
>> been merged into the kernel, why don't we just get it right this time
>> and forget about it?
>>     

I'm happy to forget about it. I've come to the conclusion that the 
IOCTLs are unmaintainable anyway. This patch at the moment is acting as 
a useful tool for exercising the underlying layers and provides a bit of 
example code (or will as the patches I have recently sent to the Linux 
Driver Project propagate through).

>> Instead of using that we implemented a heretic IOCTL-based
>> interface for user-space; at least with it you could create a
>> driver (with no interrupt support) for a device in user-space.
>> We actually don't use it, but well, just to get inspiration, here it
>> goes:
>>
>> /**
>>  * \name Window management ioctl numbers
>>  */
>> /** Get a physical window attributes */
>> #define VME_IOCTL_GET_WINDOW_ATTR       _IOWR('V', 0, struct
>> vme_mapping)
>> /** Create a physical window */
>> #define VME_IOCTL_CREATE_WINDOW         _IOW( 'V', 1, struct
>> vme_mapping)
>> /** Destroy a physical window */
>> #define VME_IOCTL_DESTROY_WINDOW        _IOW( 'V', 2, int)
>> /** Create a mapping over a physical window */
>> #define VME_IOCTL_FIND_MAPPING          _IOWR('V', 3, struct
>> vme_mapping)
>> /** Remove a mapping */
>> #define VME_IOCTL_RELEASE_MAPPING       _IOW( 'V', 4, struct
>> vme_mapping)
>> /** Get the create on find failed flag */
>> #define VME_IOCTL_GET_CREATE_ON_FIND_FAIL       _IOR( 'V', 5, unsigned
>> int)
>> /** Set the create on find failed flag */
>> #define VME_IOCTL_SET_CREATE_ON_FIND_FAIL       _IOW( 'V', 6, unsigned
>> int)
>> /** Get the destroy on remove flag */
>> #define VME_IOCTL_GET_DESTROY_ON_REMOVE _IOR( 'V', 7, unsigned int)
>> /** Set the destroy on remove flag */
>> #define VME_IOCTL_SET_DESTROY_ON_REMOVE _IOW( 'V', 8, unsigned int)
>> /** Get bus error status */
>> #define VME_IOCTL_GET_BUS_ERROR         _IOR( 'V', 9, unsigned int)
>> /** Start a DMA transfer */
>> #define VME_IOCTL_START_DMA             _IOWR('V', 10, struct vme_dma)
>>
>> [ grab the code from here: http://repo.or.cz/w/tsi148vmebridge.git .
>>   Please note there's some backwards-compatible crap for old user-space
>>   LynxOS code, called CES. Ignore it. ]
>>
>>     
I am moving the interface in that direction, I remain unconvinced about 
the contents of your vme_mapping structure, it's too tsi-148 specific.

>> By the way, please try to be consistent with naming, e.g. I see window,
>> then see "image", and I have to think hard to see whether they mean
>> the same or not.. err, do they?
>>     
Yes - I don't know where image came from, probably one of the old VME 
drivers I looked at. I will look at getting rid of that term.

Martyn
>> E.
>>
>> (I'll leave this here because of added Cc)
>> Greg K-H wrote:
>>     
>>> From: Martyn Welch <martyn.welch@...anuc.com>
>>>
>>> Adds a VME userspace access driver
>>>
>>> Signed-off-by: Martyn Welch <martyn.welch@...anuc.com>
>>> Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>
>>>
>>> ---
>>>  drivers/staging/vme/Kconfig            |    4 
>>>  drivers/staging/vme/Makefile           |    2 
>>>  drivers/staging/vme/devices/Kconfig    |    8 
>>>  drivers/staging/vme/devices/Makefile   |    5 
>>>  drivers/staging/vme/devices/vme_user.c |  771 +++++++++++++++++++++++++++++++++
>>>  drivers/staging/vme/devices/vme_user.h |   43 +
>>>  6 files changed, 830 insertions(+), 3 deletions(-)
>>>
>>> --- /dev/null
>>> +++ b/drivers/staging/vme/devices/Kconfig
>>> @@ -0,0 +1,8 @@
>>> +comment "VME Device Drivers"
>>> +
>>> +config VME_USER
>>> +	tristate "VME user space access driver"
>>> +	help
>>> +	  If you say Y here you want to be able to access a limited number of
>>> +	  VME windows in a manner at least semi-compatible with the interface
>>> +	  provided with the original driver at http://vmelinux.org/.
>>> --- /dev/null
>>> +++ b/drivers/staging/vme/devices/Makefile
>>> @@ -0,0 +1,5 @@
>>> +#
>>> +# Makefile for the VME device drivers.
>>> +#
>>> +
>>> +obj-$(CONFIG_VME_USER)		+= vme_user.o
>>> --- /dev/null
>>> +++ b/drivers/staging/vme/devices/vme_user.c
>>> @@ -0,0 +1,771 @@
>>> +/*
>>> + * VMEbus User access driver
>>> + *
>>> + * Author: Martyn Welch <martyn.welch@...anuc.com>
>>> + * Copyright 2008 GE Fanuc Intelligent Platforms Embedded Systems, Inc.
>>> + *
>>> + * Based on work by:
>>> + *   Tom Armistead and Ajit Prem
>>> + *     Copyright 2004 Motorola Inc.
>>> + *
>>> + *
>>> + * This program is free software; you can redistribute  it and/or modify it
>>> + * under  the terms of  the GNU General  Public License as published by the
>>> + * Free Software Foundation;  either version 2 of the  License, or (at your
>>> + * option) any later version.
>>> + */
>>> +
>>> +#include <linux/cdev.h>
>>> +#include <linux/delay.h>
>>> +#include <linux/device.h>
>>> +#include <linux/dma-mapping.h>
>>> +#include <linux/errno.h>
>>> +#include <linux/init.h>
>>> +#include <linux/ioctl.h>
>>> +#include <linux/kernel.h>
>>> +#include <linux/mm.h>
>>> +#include <linux/module.h>
>>> +#include <linux/pagemap.h>
>>> +#include <linux/pci.h>
>>> +#include <linux/semaphore.h>
>>> +#include <linux/spinlock.h>
>>> +#include <linux/syscalls.h>
>>> +#include <linux/types.h>
>>> +#include <linux/version.h>
>>> +
>>> +#include <asm/io.h>
>>> +#include <asm/uaccess.h>
>>> +
>>> +#include "../vme.h"
>>> +#include "vme_user.h"
>>> +
>>> +/* Currently Documentation/devices.txt defines the following for VME:
>>> + *
>>> + * 221 char	VME bus
>>> + * 		  0 = /dev/bus/vme/m0		First master image
>>> + * 		  1 = /dev/bus/vme/m1		Second master image
>>> + * 		  2 = /dev/bus/vme/m2		Third master image
>>> + * 		  3 = /dev/bus/vme/m3		Fourth master image
>>> + * 		  4 = /dev/bus/vme/s0		First slave image
>>> + * 		  5 = /dev/bus/vme/s1		Second slave image
>>> + * 		  6 = /dev/bus/vme/s2		Third slave image
>>> + * 		  7 = /dev/bus/vme/s3		Fourth slave image
>>> + * 		  8 = /dev/bus/vme/ctl		Control
>>> + *
>>> + * 		It is expected that all VME bus drivers will use the
>>> + * 		same interface.  For interface documentation see
>>> + * 		http://www.vmelinux.org/.
>>> + *
>>> + * However the VME driver at http://www.vmelinux.org/ is rather old and doesn't
>>> + * even support the tsi148 chipset (which has 8 master and 8 slave windows).
>>> + * We'll run with this or now as far as possible, however it probably makes
>>> + * sense to get rid of the old mappings and just do everything dynamically.
>>> + *
>>> + * So for now, we'll restrict the driver to providing 4 masters and 4 slaves as
>>> + * defined above and try to support at least some of the interface from
>>> + * http://www.vmelinux.org/ as an alternative drive can be written providing a
>>> + * saner interface later.
>>> + */
>>> +#define VME_MAJOR	221	/* VME Major Device Number */
>>> +#define VME_DEVS	9	/* Number of dev entries */
>>> +
>>> +#define MASTER_MINOR	0
>>> +#define MASTER_MAX	3
>>> +#define SLAVE_MINOR	4
>>> +#define SLAVE_MAX	7
>>> +#define CONTROL_MINOR	8
>>> +
>>> +#define PCI_BUF_SIZE  0x20000	/* Size of one slave image buffer */
>>> +
>>> +/*
>>> + * Structure to handle image related parameters.
>>> + */
>>> +typedef struct {
>>> +	void __iomem *kern_buf;	/* Buffer address in kernel space */
>>> +	dma_addr_t pci_buf;	/* Buffer address in PCI address space */
>>> +	unsigned long long size_buf;	/* Buffer size */
>>> +	struct semaphore sem;	/* Semaphore for locking image */
>>> +	struct device *device;	/* Sysfs device */
>>> +	struct vme_resource *resource;	/* VME resource */
>>> +	int users;		/* Number of current users */
>>> +} image_desc_t;
>>> +static image_desc_t image[VME_DEVS];
>>> +
>>> +typedef struct {
>>> +	unsigned long reads;
>>> +	unsigned long writes;
>>> +	unsigned long ioctls;
>>> +	unsigned long irqs;
>>> +	unsigned long berrs;
>>> +	unsigned long dmaErrors;
>>> +	unsigned long timeouts;
>>> +	unsigned long external;
>>> +} driver_stats_t;
>>> +static driver_stats_t statistics;
>>> +
>>> +struct cdev *vme_user_cdev;		/* Character device */
>>> +struct class *vme_user_sysfs_class;	/* Sysfs class */
>>> +struct device *vme_user_bridge;		/* Pointer to the bridge device */
>>> +
>>> +static char driver_name[] = "vme_user";
>>> +
>>> +static const int type[VME_DEVS] = {	MASTER_MINOR,	MASTER_MINOR,
>>> +					MASTER_MINOR,	MASTER_MINOR,
>>> +					SLAVE_MINOR,	SLAVE_MINOR,
>>> +					SLAVE_MINOR,	SLAVE_MINOR,
>>> +					CONTROL_MINOR
>>> +				};
>>> +
>>> +
>>> +static int vme_user_open(struct inode *, struct file *);
>>> +static int vme_user_release(struct inode *, struct file *);
>>> +static ssize_t vme_user_read(struct file *, char *, size_t, loff_t *);
>>> +static ssize_t vme_user_write(struct file *, const char *, size_t, loff_t *);
>>> +static loff_t vme_user_llseek(struct file *, loff_t, int);
>>> +static int vme_user_ioctl(struct inode *, struct file *, unsigned int,
>>> +	unsigned long);
>>> +
>>> +static int __init vme_user_probe(struct device *dev);
>>> +
>>> +static struct file_operations vme_user_fops = {
>>> +        .open = vme_user_open,
>>> +        .release = vme_user_release,
>>> +        .read = vme_user_read,
>>> +        .write = vme_user_write,
>>> +        .llseek = vme_user_llseek,
>>> +        .ioctl = vme_user_ioctl,
>>> +};
>>> +
>>> +
>>> +/*
>>> + * Reset all the statistic counters
>>> + */
>>> +static void reset_counters(void)
>>> +{
>>> +        statistics.reads = 0;
>>> +        statistics.writes = 0;
>>> +        statistics.ioctls = 0;
>>> +        statistics.irqs = 0;
>>> +        statistics.berrs = 0;
>>> +        statistics.dmaErrors = 0;
>>> +        statistics.timeouts = 0;
>>> +}
>>> +
>>> +void lmcall(int monitor)
>>> +{
>>> +	printk("Caught Location Monitor %d access\n", monitor);
>>> +}
>>> +
>>> +static void tests(void)
>>> +{
>>> +	struct vme_resource *dma_res;
>>> +	struct vme_dma_list *dma_list;
>>> +	struct vme_dma_attr *pattern_attr, *vme_attr;
>>> +
>>> +	int retval;
>>> +	unsigned int data;
>>> +
>>> +	printk("Running VME DMA test\n");
>>> +	dma_res = vme_request_dma(vme_user_bridge);
>>> +	dma_list = vme_new_dma_list(dma_res);
>>> +	pattern_attr = vme_dma_pattern_attribute(0x0,
>>> +		VME_DMA_PATTERN_WORD |
>>> +			VME_DMA_PATTERN_INCREMENT);
>>> +	vme_attr = vme_dma_vme_attribute(0x10000, VME_A32,
>>> +		VME_SCT, VME_D32);
>>> +	retval = vme_dma_list_add(dma_list, pattern_attr,
>>> +		vme_attr, 0x10000);
>>> +#if 0
>>> +	vme_dma_free_attribute(vme_attr);
>>> +	vme_attr = vme_dma_vme_attribute(0x20000, VME_A32,
>>> +		VME_SCT, VME_D32);
>>> +	retval = vme_dma_list_add(dma_list, pattern_attr,
>>> +		vme_attr, 0x10000);
>>> +#endif
>>> +	retval = vme_dma_list_exec(dma_list);
>>> +	vme_dma_free_attribute(pattern_attr);
>>> +	vme_dma_free_attribute(vme_attr);
>>> +	vme_dma_list_free(dma_list);
>>> +#if 0
>>> +	printk("Generating a VME interrupt\n");
>>> +	vme_generate_irq(dma_res, 0x3, 0xaa);
>>> +	printk("Interrupt returned\n");
>>> +#endif
>>> +	vme_dma_free(dma_res);
>>> +
>>> +	/* Attempt RMW */
>>> +	data = vme_master_rmw(image[0].resource, 0x80000000, 0x00000000,
>>> +		0x80000000, 0);
>>> +	printk("RMW returned 0x%8.8x\n", data);
>>> +
>>> +
>>> +	/* Location Monitor */
>>> +	printk("vme_lm_set:%d\n", vme_lm_set(vme_user_bridge, 0x60000, VME_A32, VME_SCT | VME_USER | VME_DATA));
>>> +	printk("vme_lm_attach:%d\n", vme_lm_attach(vme_user_bridge, 0, lmcall));
>>> +
>>> +	printk("Board in VME slot:%d\n", vme_slot_get(vme_user_bridge));
>>> +}
>>> +
>>> +static int vme_user_open(struct inode *inode, struct file *file)
>>> +{
>>> +	int err;
>>> +	unsigned int minor = MINOR(inode->i_rdev);
>>> +
>>> +	down(&image[minor].sem);
>>> +	/* Only allow device to be opened if a resource is allocated */
>>> +	if (image[minor].resource == NULL) {
>>> +		printk(KERN_ERR "No resources allocated for device\n");
>>> +		err = -EINVAL;
>>> +		goto err_res;
>>> +	}
>>> +
>>> +	/* Increment user count */
>>> +	image[minor].users++;
>>> +
>>> +	up(&image[minor].sem);
>>> +
>>> +	return 0;
>>> +
>>> +err_res:
>>> +	up(&image[minor].sem);
>>> +
>>> +	return err;
>>> +}
>>> +
>>> +static int vme_user_release(struct inode *inode, struct file *file)
>>> +{
>>> +	unsigned int minor = MINOR(inode->i_rdev);
>>> +
>>> +	down(&image[minor].sem);
>>> +
>>> +	/* Decrement user count */
>>> +	image[minor].users--;
>>> +
>>> +	up(&image[minor].sem);
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +/*
>>> + * We are going ot alloc a page during init per window for small transfers.
>>> + * Small transfers will go VME -> buffer -> user space. Larger (more than a
>>> + * page) transfers will lock the user space buffer into memory and then
>>> + * transfer the data directly into the user space buffers.
>>> + */
>>> +static ssize_t resource_to_user(int minor, char __user *buf, size_t count,
>>> +	loff_t *ppos)
>>> +{
>>> +	ssize_t retval;
>>> +	ssize_t copied = 0;
>>> +
>>> +	if (count <= image[minor].size_buf) {
>>> +		/* We copy to kernel buffer */
>>> +		copied = vme_master_read(image[minor].resource,
>>> +			image[minor].kern_buf, count, *ppos);
>>> +		if (copied < 0) {
>>> +			return (int)copied;
>>> +		}
>>> +
>>> +		retval = __copy_to_user(buf, image[minor].kern_buf,
>>> +			(unsigned long)copied);
>>> +		if (retval != 0) {
>>> +			copied = (copied - retval);
>>> +			printk("User copy failed\n");
>>> +			return -EINVAL;
>>> +		}
>>> +
>>> +	} else {
>>> +		/* XXX Need to write this */
>>> +		printk("Currently don't support large transfers\n");
>>> +		/* Map in pages from userspace */
>>> +
>>> +		/* Call vme_master_read to do the transfer */
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	return copied;
>>> +}
>>> +
>>> +/*
>>> + * We are going ot alloc a page during init per window for small transfers.
>>> + * Small transfers will go user space -> buffer -> VME. Larger (more than a
>>> + * page) transfers will lock the user space buffer into memory and then
>>> + * transfer the data directly from the user space buffers out to VME.
>>> + */
>>> +static ssize_t resource_from_user(unsigned int minor, const char *buf,
>>> +	size_t count, loff_t *ppos)
>>> +{
>>> +	ssize_t retval;
>>> +	ssize_t copied = 0;
>>> +
>>> +	if (count <= image[minor].size_buf) {
>>> +		retval = __copy_from_user(image[minor].kern_buf, buf,
>>> +			(unsigned long)count);
>>> +		if (retval != 0)
>>> +			copied = (copied - retval);
>>> +		else
>>> +			copied = count;
>>> +
>>> +		copied = vme_master_write(image[minor].resource,
>>> +			image[minor].kern_buf, copied, *ppos);
>>> +	} else {
>>> +		/* XXX Need to write this */
>>> +		printk("Currently don't support large transfers\n");
>>> +		/* Map in pages from userspace */
>>> +
>>> +		/* Call vme_master_write to do the transfer */
>>> +		return -EINVAL;
>>> +	}
>>> +
>>> +	return copied;
>>> +}
>>> +
>>> +static ssize_t buffer_to_user(unsigned int minor, char __user *buf,
>>> +	size_t count, loff_t *ppos)
>>> +{
>>> +	void __iomem *image_ptr;
>>> +	ssize_t retval;
>>> +
>>> +	image_ptr = image[minor].kern_buf + *ppos;
>>> +
>>> +	retval = __copy_to_user(buf, image_ptr, (unsigned long)count);
>>> +	if (retval != 0) {
>>> +		retval = (count - retval);
>>> +		printk(KERN_WARNING "Partial copy to userspace\n");
>>> +	} else
>>> +		retval = count;
>>> +
>>> +	/* Return number of bytes successfully read */
>>> +	return retval;
>>> +}
>>> +
>>> +static ssize_t buffer_from_user(unsigned int minor, const char *buf,
>>> +	size_t count, loff_t *ppos)
>>> +{
>>> +	void __iomem *image_ptr;
>>> +	size_t retval;
>>> +
>>> +	image_ptr = image[minor].kern_buf + *ppos;
>>> +
>>> +	retval = __copy_from_user(image_ptr, buf, (unsigned long)count);
>>> +	if (retval != 0) {
>>> +		retval = (count - retval);
>>> +		printk(KERN_WARNING "Partial copy to userspace\n");
>>> +	} else
>>> +		retval = count;
>>> +
>>> +	/* Return number of bytes successfully read */
>>> +	return retval;
>>> +}
>>> +
>>> +static ssize_t vme_user_read(struct file *file, char *buf, size_t count,
>>> +			loff_t * ppos)
>>> +{
>>> +	unsigned int minor = MINOR(file->f_dentry->d_inode->i_rdev);
>>> +	ssize_t retval;
>>> +	size_t image_size;
>>> +	size_t okcount;
>>> +
>>> +	down(&image[minor].sem);
>>> +
>>> +	/* XXX Do we *really* want this helper - we can use vme_*_get ? */
>>> +	image_size = vme_get_size(image[minor].resource);
>>> +
>>> +	/* Ensure we are starting at a valid location */
>>> +	if ((*ppos < 0) || (*ppos > (image_size - 1))) {
>>> +		up(&image[minor].sem);
>>> +		return 0;
>>> +	}
>>> +
>>> +	/* Ensure not reading past end of the image */
>>> +	if (*ppos + count > image_size)
>>> +		okcount = image_size - *ppos;
>>> +	else
>>> +		okcount = count;
>>> +
>>> +	switch (type[minor]){
>>> +	case MASTER_MINOR:
>>> +		retval = resource_to_user(minor, buf, okcount, ppos);
>>> +		break;
>>> +	case SLAVE_MINOR:
>>> +		retval = buffer_to_user(minor, buf, okcount, ppos);
>>> +		break;
>>> +	default:
>>> +		retval = -EINVAL;
>>> +	}
>>> +
>>> +	up(&image[minor].sem);
>>> +
>>> +	if (retval > 0)
>>> +		*ppos += retval;
>>> +
>>> +	return retval;
>>> +}
>>> +
>>> +static ssize_t vme_user_write(struct file *file, const char *buf, size_t count,
>>> +			 loff_t *ppos)
>>> +{
>>> +	unsigned int minor = MINOR(file->f_dentry->d_inode->i_rdev);
>>> +	ssize_t retval;
>>> +	size_t image_size;
>>> +	size_t okcount;
>>> +
>>> +	down(&image[minor].sem);
>>> +
>>> +	image_size = vme_get_size(image[minor].resource);
>>> +
>>> +	/* Ensure we are starting at a valid location */
>>> +	if ((*ppos < 0) || (*ppos > (image_size - 1))) {
>>> +		up(&image[minor].sem);
>>> +		return 0;
>>> +	}
>>> +
>>> +	/* Ensure not reading past end of the image */
>>> +	if (*ppos + count > image_size)
>>> +		okcount = image_size - *ppos;
>>> +	else
>>> +		okcount = count;
>>> +
>>> +	switch (type[minor]){
>>> +	case MASTER_MINOR:
>>> +		retval = resource_from_user(minor, buf, okcount, ppos);
>>> +		break;
>>> +	case SLAVE_MINOR:
>>> +		retval = buffer_from_user(minor, buf, okcount, ppos);
>>> +		break;
>>> +	default:
>>> +		retval = -EINVAL;
>>> +	}
>>> +
>>> +	up(&image[minor].sem);
>>> +
>>> +	if (retval > 0)
>>> +		*ppos += retval;
>>> +
>>> +	return retval;
>>> +}
>>> +
>>> +static loff_t vme_user_llseek(struct file *file, loff_t off, int whence)
>>> +{
>>> +	printk(KERN_ERR "Llseek currently incomplete\n");
>>> +	return -EINVAL;
>>> +}
>>> +
>>> +static int vme_user_ioctl(struct inode *inode, struct file *file,
>>> +	unsigned int cmd, unsigned long arg)
>>> +{
>>> +	unsigned int minor = MINOR(inode->i_rdev);
>>> +#if 0
>>> +	int ret_val;
>>> +#endif
>>> +	unsigned long copyRet;
>>> +	vme_slave_t slave;
>>> +
>>> +	statistics.ioctls++;
>>> +	switch (type[minor]) {
>>> +	case CONTROL_MINOR:
>>> +		break;
>>> +	case MASTER_MINOR:
>>> +		break;
>>> +	case SLAVE_MINOR:
>>> +		switch (cmd) {
>>> +		case VME_SET_SLAVE:
>>> +
>>> +			copyRet = copy_from_user(&slave, (char *)arg,
>>> +				sizeof(slave));
>>> +			if (copyRet != 0) {
>>> +				printk(KERN_WARNING "Partial copy from "
>>> +					"userspace\n");
>>> +				return -EFAULT;
>>> +			}
>>> +
>>> +			return vme_slave_set(image[minor].resource,
>>> +				slave.enable, slave.vme_addr, slave.size,
>>> +				image[minor].pci_buf, slave.aspace,
>>> +				slave.cycle);
>>> +
>>> +			break;
>>> +#if 0
>>> +		case VME_GET_SLAVE:
>>> +			vme_slave_t slave;
>>> +
>>> +			ret_val = vme_slave_get(minor, &iRegs);
>>> +
>>> +			copyRet = copy_to_user((char *)arg, &slave,
>>> +				sizeof(slave));
>>> +			if (copyRet != 0) {
>>> +				printk(KERN_WARNING "Partial copy to "
>>> +					"userspace\n");
>>> +				return -EFAULT;
>>> +			}
>>> +
>>> +			return ret_val;
>>> +			break;
>>> +#endif
>>> +		}
>>> +		break;
>>> +	}
>>> +
>>> +	return -EINVAL;
>>> +}
>>> +
>>> +
>>> +/*
>>> + * Unallocate a previously allocated buffer
>>> + */
>>> +static void buf_unalloc (int num)
>>> +{
>>> +	if (image[num].kern_buf) {
>>> +#ifdef VME_DEBUG
>>> +		printk(KERN_DEBUG "UniverseII:Releasing buffer at %p\n",
>>> +			image[num].pci_buf);
>>> +#endif
>>> +
>>> +		vme_free_consistent(image[num].resource, image[num].size_buf,
>>> +			image[num].kern_buf, image[num].pci_buf);
>>> +
>>> +		image[num].kern_buf = NULL;
>>> +		image[num].pci_buf = 0;
>>> +		image[num].size_buf = 0;
>>> +
>>> +#ifdef VME_DEBUG
>>> +	} else {
>>> +		printk(KERN_DEBUG "UniverseII: Buffer not allocated\n");
>>> +#endif
>>> +	}
>>> +}
>>> +
>>> +static struct vme_driver vme_user_driver = {
>>> +        .name = driver_name,
>>> +        .probe = vme_user_probe,
>>> +};
>>> +
>>> +
>>> +/*
>>> + * In this simple access driver, the old behaviour is being preserved as much
>>> + * as practical. We will therefore reserve the buffers and request the images
>>> + * here so that we don't have to do it later.
>>> + */
>>> +static int __init vme_bridge_init(void)
>>> +{
>>> +	int retval;
>>> +	printk(KERN_INFO "VME User Space Access Driver\n");
>>> +	printk("vme_user_driver:%p\n", &vme_user_driver);
>>> +	retval = vme_register_driver(&vme_user_driver);
>>> +	printk("vme_register_driver returned %d\n", retval);
>>> +	return retval;
>>> +}
>>> +
>>> +/*
>>> + * This structure gets passed a device, this should be the device created at
>>> + * registration.
>>> + */
>>> +static int __init vme_user_probe(struct device *dev)
>>> +{
>>> +	int i, err;
>>> +	char name[8];
>>> +
>>> +	printk("Running vme_user_probe()\n");
>>> +
>>> +	/* Pointer to the bridge device */
>>> +	vme_user_bridge = dev;
>>> +
>>> +	/* Initialise descriptors */
>>> +	for (i = 0; i < VME_DEVS; i++) {
>>> +		image[i].kern_buf = NULL;
>>> +		image[i].pci_buf = 0;
>>> +		init_MUTEX(&(image[i].sem));
>>> +		image[i].device = NULL;
>>> +		image[i].resource = NULL;
>>> +		image[i].users = 0;
>>> +	}
>>> +
>>> +	/* Initialise statistics counters */
>>> +	reset_counters();
>>> +
>>> +	/* Assign major and minor numbers for the driver */
>>> +	err = register_chrdev_region(MKDEV(VME_MAJOR, 0), VME_DEVS,
>>> +		driver_name);
>>> +	if (err) {
>>> +		printk(KERN_WARNING "%s: Error getting Major Number %d for "
>>> +		"driver.\n", driver_name, VME_MAJOR);
>>> +		goto err_region;
>>> +	}
>>> +
>>> +	/* Register the driver as a char device */
>>> +	vme_user_cdev = cdev_alloc();
>>> +	vme_user_cdev->ops = &vme_user_fops;
>>> +	vme_user_cdev->owner = THIS_MODULE;
>>> +	err = cdev_add(vme_user_cdev, MKDEV(VME_MAJOR, 0), VME_DEVS);
>>> +	if (err) {
>>> +		printk(KERN_WARNING "%s: cdev_all failed\n", driver_name);
>>> +		goto err_char;
>>> +	}
>>> +
>>> +	/* Request slave resources and allocate buffers (128kB wide) */
>>> +	for (i = SLAVE_MINOR; i < (SLAVE_MAX + 1); i++) {
>>> +		/* XXX Need to properly request attributes */
>>> +		image[i].resource = vme_slave_request(vme_user_bridge,
>>> +			VME_A16, VME_SCT);
>>> +		if (image[i].resource == NULL) {
>>> +			printk(KERN_WARNING "Unable to allocate slave "
>>> +				"resource\n");
>>> +			goto err_buf;
>>> +		}
>>> +		image[i].size_buf = PCI_BUF_SIZE;
>>> +		image[i].kern_buf = vme_alloc_consistent(image[i].resource,
>>> +			image[i].size_buf, &(image[i].pci_buf));
>>> +		if (image[i].kern_buf == NULL) {
>>> +			printk(KERN_WARNING "Unable to allocate memory for "
>>> +				"buffer\n");
>>> +			image[i].pci_buf = 0;
>>> +			vme_slave_free(image[i].resource);
>>> +			err = -ENOMEM;
>>> +			goto err_buf;
>>> +		}
>>> +	}
>>> +
>>> +	/*
>>> +	 * Request master resources allocate page sized buffers for small
>>> +	 * reads and writes
>>> +	 */
>>> +	for (i = MASTER_MINOR; i < (MASTER_MAX + 1); i++) {
>>> +		/* XXX Need to properly request attributes */
>>> +		image[i].resource = vme_master_request(vme_user_bridge,
>>> +			VME_A32, VME_SCT, VME_D32);
>>> +		if (image[i].resource == NULL) {
>>> +			printk(KERN_WARNING "Unable to allocate master "
>>> +				"resource\n");
>>> +			goto err_buf;
>>> +		}
>>> +		image[i].size_buf = PAGE_SIZE;
>>> +		image[i].kern_buf = vme_alloc_consistent(image[i].resource,
>>> +			image[i].size_buf, &(image[i].pci_buf));
>>> +		if (image[i].kern_buf == NULL) {
>>> +			printk(KERN_WARNING "Unable to allocate memory for "
>>> +				"buffer\n");
>>> +			image[i].pci_buf = 0;
>>> +			vme_master_free(image[i].resource);
>>> +			err = -ENOMEM;
>>> +			goto err_buf;
>>> +		}
>>> +	}
>>> +
>>> +	/* Setup some debug windows */
>>> +	for (i = SLAVE_MINOR; i < (SLAVE_MAX + 1); i++) {
>>> +		err = vme_slave_set(image[i].resource, 1, 0x4000*(i-4),
>>> +			0x4000, image[i].pci_buf, VME_A16,
>>> +			VME_SCT | VME_SUPER | VME_USER | VME_PROG | VME_DATA);
>>> +		if (err != 0) {
>>> +			printk(KERN_WARNING "Failed to configure window\n");
>>> +			goto err_buf;
>>> +		}
>>> +	}
>>> +	for (i = MASTER_MINOR; i < (MASTER_MAX + 1); i++) {
>>> +		err = vme_master_set(image[i].resource, 1,
>>> +			(0x10000 + (0x10000*i)), 0x10000,
>>> +			VME_A32, VME_SCT | VME_USER | VME_DATA, VME_D32);
>>> +		if (err != 0) {
>>> +			printk(KERN_WARNING "Failed to configure window\n");
>>> +			goto err_buf;
>>> +		}
>>> +	}
>>> +
>>> +	/* Create sysfs entries - on udev systems this creates the dev files */
>>> +	vme_user_sysfs_class = class_create(THIS_MODULE, driver_name);
>>> +	if (IS_ERR(vme_user_sysfs_class)) {
>>> +		printk(KERN_ERR "Error creating vme_user class.\n");
>>> +		err = PTR_ERR(vme_user_sysfs_class);
>>> +		goto err_class;
>>> +	}
>>> +
>>> +	/* Add sysfs Entries */
>>> +	for (i=0; i<VME_DEVS; i++) {
>>> +		switch (type[i]) {
>>> +		case MASTER_MINOR:
>>> +			sprintf(name,"bus/vme/m%%d");
>>> +			break;
>>> +		case CONTROL_MINOR:
>>> +			sprintf(name,"bus/vme/ctl");
>>> +			break;
>>> +		case SLAVE_MINOR:
>>> +			sprintf(name,"bus/vme/s%%d");
>>> +			break;
>>> +		default:
>>> +			err = -EINVAL;
>>> +			goto err_sysfs;
>>> +			break;
>>> +		}
>>> +
>>> +		image[i].device =
>>> +			device_create(vme_user_sysfs_class, NULL,
>>> +				MKDEV(VME_MAJOR, i), NULL, name,
>>> +				(type[i] == SLAVE_MINOR)? i - (MASTER_MAX + 1) : i);
>>> +		if (IS_ERR(image[i].device)) {
>>> +			printk("%s: Error creating sysfs device\n",
>>> +				driver_name);
>>> +			err = PTR_ERR(image[i].device);
>>> +			goto err_sysfs;
>>> +		}
>>> +	}
>>> +
>>> +	/* XXX Run tests */
>>> +	/*
>>> +	tests();
>>> +	*/
>>> +
>>> +	return 0;
>>> +
>>> +	/* Ensure counter set correcty to destroy all sysfs devices */
>>> +	i = VME_DEVS;
>>> +err_sysfs:
>>> +	while (i > 0){
>>> +		i--;
>>> +		device_destroy(vme_user_sysfs_class, MKDEV(VME_MAJOR, i));
>>> +	}
>>> +	class_destroy(vme_user_sysfs_class);
>>> +
>>> +	/* Ensure counter set correcty to unalloc all slave buffers */
>>> +	i = SLAVE_MAX + 1;
>>> +err_buf:
>>> +	while (i > SLAVE_MINOR){
>>> +		i--;
>>> +		vme_slave_set(image[i].resource, 0, 0, 0, 0, VME_A32, 0);
>>> +		vme_slave_free(image[i].resource);
>>> +		buf_unalloc(i);
>>> +	}
>>> +err_class:
>>> +	cdev_del(vme_user_cdev);
>>> +err_char:
>>> +	unregister_chrdev_region(MKDEV(VME_MAJOR, 0), VME_DEVS);
>>> +err_region:
>>> +	return err;
>>> +}
>>> +
>>> +static void __exit vme_bridge_exit(void)
>>> +{
>>> +	int i;
>>> +
>>> +	/* Remove sysfs Entries */
>>> +	for(i=0; i<VME_DEVS; i++) {
>>> +		device_destroy(vme_user_sysfs_class, MKDEV(VME_MAJOR, i));
>>> +	}
>>> +	class_destroy(vme_user_sysfs_class);
>>> +
>>> +	for (i = SLAVE_MINOR; i < (SLAVE_MAX + 1); i++) {
>>> +		buf_unalloc(i);
>>> +	}
>>> +
>>> +	/* Unregister device driver */
>>> +	cdev_del(vme_user_cdev);
>>> +
>>> +	/* Unregiser the major and minor device numbers */
>>> +	unregister_chrdev_region(MKDEV(VME_MAJOR, 0), VME_DEVS);
>>> +}
>>> +
>>> +MODULE_DESCRIPTION("VME User Space Access Driver");
>>> +MODULE_AUTHOR("Martyn Welch <martyn.welch@...anuc.com");
>>> +MODULE_LICENSE("GPL");
>>> +
>>> +module_init(vme_bridge_init);
>>> +module_exit(vme_bridge_exit);
>>> --- /dev/null
>>> +++ b/drivers/staging/vme/devices/vme_user.h
>>> @@ -0,0 +1,43 @@
>>> +
>>> +/*
>>> + * VMEbus Master Window Configuration Structure
>>> + */
>>> +typedef struct {
>>> +	char enable;			/* State of Window */
>>> +	unsigned long long vme_addr;	/* Starting Address on the VMEbus */
>>> +	unsigned long long size;	/* Window Size */
>>> +	vme_address_t aspace;		/* Address Space */
>>> +	vme_cycle_t cycle;		/* Cycle properties */
>>> +	vme_width_t dwidth;		/* Maximum Data Width */
>>> +#if 0
>>> +	char prefetchEnable;		/* Prefetch Read Enable State */
>>> +	int prefetchSize;		/* Prefetch Read Size (Cache Lines) */
>>> +	char wrPostEnable;		/* Write Post State */
>>> +#endif
>>> +} vme_master_t;
>>> +
>>> +
>>> +/*
>>> + * IOCTL Commands and structures
>>> + */
>>> +
>>> +/* Magic number for use in ioctls */
>>> +#define VME_IOC_MAGIC 0xAE
>>> +
>>> +
>>> +/* VMEbus Slave Window Configuration Structure */
>>> +typedef struct {
>>> +	char enable;			/* State of Window */
>>> +	unsigned long long vme_addr;	/* Starting Address on the VMEbus */
>>> +	unsigned long long size;	/* Window Size */
>>> +	vme_address_t aspace;		/* Address Space */
>>> +	vme_cycle_t cycle;		/* Cycle properties */
>>> +#if 0
>>> +	char wrPostEnable;		/* Write Post State */
>>> +	char rmwLock;			/* Lock PCI during RMW Cycles */
>>> +	char data64BitCapable;		/* non-VMEbus capable of 64-bit Data */
>>> +#endif
>>> +} vme_slave_t;
>>> +
>>> +#define VME_SET_SLAVE _IOW(VME_IOC_MAGIC, 10, vme_slave_t)
>>> +
>>> --- a/drivers/staging/vme/Kconfig
>>> +++ b/drivers/staging/vme/Kconfig
>>> @@ -11,7 +11,7 @@ menuconfig VME
>>>  if VME
>>>  
>>>  #source "drivers/staging/vme/bridges/Kconfig"
>>> -#
>>> -#source "drivers/staging/vme/devices/Kconfig"
>>> +
>>> +source "drivers/staging/vme/devices/Kconfig"
>>>  
>>>  endif # VME
>>> --- a/drivers/staging/vme/Makefile
>>> +++ b/drivers/staging/vme/Makefile
>>> @@ -4,4 +4,4 @@
>>>  obj-$(CONFIG_VME)		+= vme.o
>>>  
>>>  #obj-y				+= bridges/
>>> -#obj-y				+= devices/
>>> +obj-y				+= devices/
>>>
>>>
>>>       


-- 
Martyn Welch MEng MPhil MIET (Principal Software Engineer)   T:+44(0)1327322748
GE Fanuc Intelligent Platforms Ltd,        |Registered in England and Wales
Tove Valley Business Park, Towcester,      |(3828642) at 100 Barbirolli Square,
Northants, NN12 6PF, UK T:+44(0)1327359444 |Manchester,M2 3AB  VAT:GB 927559189
--
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