Commit c77a6794 authored by Jeremy Sowden's avatar Jeremy Sowden Committed by Greg Kroah-Hartman
Browse files

staging: kpc2000: removed DMA AIO implementation. 



The existing implementation for doing DMA via asynchronous IO didn't
work and there was no longer a use-case for it.  Removed it.

Fixed a few checkpatch warnings about too-long lines and extraneous
braces in the process.

Reported-by: default avatarMatt Sickler <matt.sickler@daktronics.com>
Signed-off-by: default avatarJeremy Sowden <jeremy@azazel.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent eafae15f

drivers/staging/kpc2000/TODO

+0 −3
Original line number Diff line number Diff line 
- the kpc_spi driver doesn't seem to let multiple transactions (to different instances of the core) happen in parallel...

- The kpc_i2c driver is a hot mess, it should probably be cleaned up a ton.  It functions against current hardware though.
 
- would be nice if the AIO fileops in kpc_dma could be made to work

    - probably want to add a CONFIG_ option to control compilation of the AIO functions

- if the AIO fileops in kpc_dma start working, next would be making iov_count > 1 work too

drivers/staging/kpc2000/kpc_dma/fileops.c

+21 −81
Original line number Diff line number Diff line
@@ -9,7 +9,6 @@ 
#include <linux/types.h>    /* size_t */

#include <linux/cdev.h>

#include <linux/uaccess.h>  /* copy_*_user */

#include <linux/aio.h>      /* aio stuff */

#include <linux/highmem.h>

#include <linux/pagemap.h>

#include "kpc_dma_driver.h"
@@ -32,8 +31,8 @@ unsigned int count_parts_for_sge(struct scatterlist *sg) 
}



/**********  Transfer Helpers  **********/

static

int  kpc_dma_transfer(struct dev_private_data *priv, struct kiocb *kcb, unsigned long iov_base, size_t iov_len)

static int kpc_dma_transfer(struct dev_private_data *priv,

			    unsigned long iov_base, size_t iov_len)

{

	unsigned int i = 0;

	long rv = 0;
@@ -65,7 +64,6 @@ int kpc_dma_transfer(struct dev_private_data *priv, struct kiocb *kcb, unsigned 
	acd->ldev = priv->ldev;

	acd->cpl = &done;

	acd->flags = 0;

	acd->kcb = kcb;

	acd->len = iov_len;

	acd->page_count = count_pages(iov_base, iov_len);
@@ -173,21 +171,18 @@ int kpc_dma_transfer(struct dev_private_data *priv, struct kiocb *kcb, unsigned 


	unlock_engine(ldev);



	// If this is a synchronous kiocb, we need to put the calling process to sleep until the transfer is complete

	if (kcb == NULL || is_sync_kiocb(kcb)) {

	rv = wait_for_completion_interruptible(&done);

		// If the user aborted (rv == -ERESTARTSYS), we're no longer responsible for cleaning up the acd

		if (rv == -ERESTARTSYS) {

	/*

	 * If the user aborted (rv == -ERESTARTSYS), we're no longer responsible

	 * for cleaning up the acd

	 */

	if (rv == -ERESTARTSYS)

		acd->cpl = NULL;

		}

	if (rv == 0) {

		rv = acd->len;

		kfree(acd);

	}

	return rv;

	}



	return -EIOCBQUEUED;



 err_descr_too_many:

	unlock_engine(ldev);
@@ -234,17 +229,13 @@ void transfer_complete_cb(struct aio_cb_data *acd, size_t xfr_count, u32 flags) 


	acd->flags = flags;



	if (acd->kcb == NULL || is_sync_kiocb(acd->kcb)) {

	if (acd->cpl) {

		complete(acd->cpl);

	} else {

			// There's no completion, so we're responsible for cleaning up the acd

			kfree(acd);

		}

	} else {

#ifdef CONFIG_KPC_DMA_AIO

		aio_complete(acd->kcb, acd->len, acd->flags);

#endif

		/*

		 * There's no completion, so we're responsible for cleaning up

		 * the acd

		 */

		kfree(acd);

	}

}
@@ -308,53 +299,6 @@ int kpc_dma_close(struct inode *inode, struct file *filp) 
	return 0;

}



#ifdef CONFIG_KPC_DMA_AIO

static

int  kpc_dma_aio_cancel(struct kiocb *kcb)

{

	struct dev_private_data *priv = (struct dev_private_data *)kcb->ki_filp->private_data;



	dev_dbg(&priv->ldev->pldev->dev, "%s(kcb = [%p]) priv = [%p], ldev = [%p]\n", __func__, kcb, priv, priv->ldev);

	return 0;

}



static

ssize_t   kpc_dma_aio_read(struct kiocb *kcb, const struct iovec *iov, unsigned long iov_count, loff_t pos)

{

	struct dev_private_data *priv = (struct dev_private_data *)kcb->ki_filp->private_data;



	if (priv->ldev->dir != DMA_FROM_DEVICE)

		return -EMEDIUMTYPE;



	if (iov_count != 1) {

		dev_err(&priv->ldev->pldev->dev, "%s() called with iov_count > 1!\n", __func__);

		return -EFAULT;

	}



	if (!is_sync_kiocb(kcb))

		kiocb_set_cancel_fn(kcb, kpc_dma_aio_cancel);

	return kpc_dma_transfer(priv, kcb, (unsigned long)iov->iov_base, iov->iov_len);

}



static

ssize_t  kpc_dma_aio_write(struct kiocb *kcb, const struct iovec *iov, unsigned long iov_count, loff_t pos)

{

	struct dev_private_data *priv = (struct dev_private_data *)kcb->ki_filp->private_data;



	if (priv->ldev->dir != DMA_TO_DEVICE)

		return -EMEDIUMTYPE;



	if (iov_count != 1) {

		dev_err(&priv->ldev->pldev->dev, "%s() called with iov_count > 1!\n", __func__);

		return -EFAULT;

	}



	if (!is_sync_kiocb(kcb))

		kiocb_set_cancel_fn(kcb, kpc_dma_aio_cancel);

	return kpc_dma_transfer(priv, kcb, (unsigned long)iov->iov_base, iov->iov_len);

}

#endif



static

ssize_t  kpc_dma_read(struct file *filp,       char __user *user_buf, size_t count, loff_t *ppos)

{
@@ -363,7 +307,7 @@ ssize_t kpc_dma_read(struct file *filp, char __user *user_buf, size_t cou 
	if (priv->ldev->dir != DMA_FROM_DEVICE)

		return -EMEDIUMTYPE;



	return kpc_dma_transfer(priv, (struct kiocb *)NULL, (unsigned long)user_buf, count);

	return kpc_dma_transfer(priv, (unsigned long)user_buf, count);

}



static
@@ -374,7 +318,7 @@ ssize_t kpc_dma_write(struct file *filp, const char __user *user_buf, size_t co 
	if (priv->ldev->dir != DMA_TO_DEVICE)

		return -EMEDIUMTYPE;



	return kpc_dma_transfer(priv, (struct kiocb *)NULL, (unsigned long)user_buf, count);

	return kpc_dma_transfer(priv, (unsigned long)user_buf, count);

}



static
@@ -402,10 +346,6 @@ const struct file_operations kpc_dma_fops = { 
	.release        = kpc_dma_close,

	.read           = kpc_dma_read,

	.write          = kpc_dma_write,

#ifdef CONFIG_KPC_DMA_AIO

	.aio_read       = kpc_dma_aio_read,

	.aio_write      = kpc_dma_aio_write,

#endif

	.unlocked_ioctl = kpc_dma_ioctl,

};

drivers/staging/kpc2000/kpc_dma/kpc_dma_driver.h

+0 −2
Original line number Diff line number Diff line
@@ -14,7 +14,6 @@ 
#include <linux/pci.h>

#include <linux/interrupt.h>

#include <linux/workqueue.h>

#include <linux/aio.h>

#include <linux/bitops.h>

#include "../kpc.h"
@@ -87,7 +86,6 @@ struct aio_cb_data { 
	struct kpc_dma_device      *ldev;

	struct completion  *cpl;

	unsigned char       flags;

	struct kiocb       *kcb;

	size_t              len;



	unsigned int        page_count;