staging: drop kpc2000 driver

It seems that the old developer is no longer with the company producing
this device, and the company has no plans on getting this out of the
staging directory at all, so let's drop the driver for now as it's
pretty much abandonded.

If someone want to support this and get it out of staging, we can easily
revert this change and bring it back.

Cc: Matt Sickler <matt.sickler@msk4.com>
Link: https://lore.kernel.org/r/20210610183153.2397760-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 0 insertions, 363 deletions

diff --git a/drivers/staging/kpc2000/kpc_dma/fileops.c b/drivers/staging/kpc2000/kpc_dma/fileops.c
deleted file mode 100644
index 10dcd6646b01..000000000000
--- a/drivers/staging/kpc2000/kpc_dma/fileops.c
+++ /dev/null
@@ -1,363 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/mm.h>
-#include <linux/kernel.h>   /* printk() */
-#include <linux/slab.h>     /* kmalloc() */
-#include <linux/fs.h>       /* everything... */
-#include <linux/errno.h>    /* error codes */
-#include <linux/types.h>    /* size_t */
-#include <linux/cdev.h>
-#include <linux/uaccess.h>  /* copy_*_user */
-#include <linux/highmem.h>
-#include <linux/pagemap.h>
-#include "kpc_dma_driver.h"
-#include "uapi.h"
-
-/**********  Helper Functions  **********/
-static inline
-unsigned int  count_pages(unsigned long iov_base, size_t iov_len)
-{
-	unsigned long first = (iov_base                 & PAGE_MASK) >> PAGE_SHIFT;
-	unsigned long last  = ((iov_base + iov_len - 1) & PAGE_MASK) >> PAGE_SHIFT;
-
-	return last - first + 1;
-}
-
-static inline
-unsigned int  count_parts_for_sge(struct scatterlist *sg)
-{
-	return DIV_ROUND_UP(sg_dma_len(sg), 0x80000);
-}
-
-/**********  Transfer Helpers  **********/
-static int kpc_dma_transfer(struct dev_private_data *priv,
-			    unsigned long iov_base, size_t iov_len)
-{
-	unsigned int i = 0;
-	int rv = 0, nr_pages = 0;
-	struct kpc_dma_device *ldev;
-	struct aio_cb_data *acd;
-	DECLARE_COMPLETION_ONSTACK(done);
-	u32 desc_needed = 0;
-	struct scatterlist *sg;
-	u32 num_descrs_avail;
-	struct kpc_dma_descriptor *desc;
-	unsigned int pcnt;
-	unsigned int p;
-	u64 card_addr;
-	u64 dma_addr;
-	u64 user_ctl;
-
-	ldev = priv->ldev;
-
-	acd = kzalloc(sizeof(*acd), GFP_KERNEL);
-	if (!acd) {
-		dev_err(&priv->ldev->pldev->dev, "Couldn't kmalloc space for the aio data\n");
-		return -ENOMEM;
-	}
-	memset(acd, 0x66, sizeof(struct aio_cb_data));
-
-	acd->priv = priv;
-	acd->ldev = priv->ldev;
-	acd->cpl = &done;
-	acd->flags = 0;
-	acd->len = iov_len;
-	acd->page_count = count_pages(iov_base, iov_len);
-
-	// Allocate an array of page pointers
-	acd->user_pages = kcalloc(acd->page_count, sizeof(struct page *),
-				  GFP_KERNEL);
-	if (!acd->user_pages) {
-		dev_err(&priv->ldev->pldev->dev, "Couldn't kmalloc space for the page pointers\n");
-		rv = -ENOMEM;
-		goto err_alloc_userpages;
-	}
-
-	// Lock the user buffer pages in memory, and hold on to the page pointers (for the sglist)
-	mmap_read_lock(current->mm);      /*  get memory map semaphore */
-	rv = pin_user_pages(iov_base, acd->page_count, FOLL_TOUCH | FOLL_WRITE,
-			    acd->user_pages, NULL);
-	mmap_read_unlock(current->mm);        /*  release the semaphore */
-	if (rv != acd->page_count) {
-		nr_pages = rv;
-		if (rv > 0)
-			rv = -EFAULT;
-
-		dev_err(&priv->ldev->pldev->dev, "Couldn't pin_user_pages (%d)\n", rv);
-		goto unpin_pages;
-	}
-	nr_pages = acd->page_count;
-
-	// Allocate and setup the sg_table (scatterlist entries)
-	rv = sg_alloc_table_from_pages(&acd->sgt, acd->user_pages, acd->page_count,
-				       iov_base & (PAGE_SIZE - 1), iov_len, GFP_KERNEL);
-	if (rv) {
-		dev_err(&priv->ldev->pldev->dev, "Couldn't alloc sg_table (%d)\n", rv);
-		goto unpin_pages;
-	}
-
-	// Setup the DMA mapping for all the sg entries
-	acd->mapped_entry_count = dma_map_sg(&ldev->pldev->dev, acd->sgt.sgl, acd->sgt.nents,
-					     ldev->dir);
-	if (acd->mapped_entry_count <= 0) {
-		dev_err(&priv->ldev->pldev->dev, "Couldn't dma_map_sg (%d)\n",
-			acd->mapped_entry_count);
-		goto free_table;
-	}
-
-	// Calculate how many descriptors are actually needed for this transfer.
-	for_each_sg(acd->sgt.sgl, sg, acd->mapped_entry_count, i) {
-		desc_needed += count_parts_for_sge(sg);
-	}
-
-	lock_engine(ldev);
-
-	// Figoure out how many descriptors are available and return an error if there aren't enough
-	num_descrs_avail = count_descriptors_available(ldev);
-	dev_dbg(&priv->ldev->pldev->dev,
-		"    mapped_entry_count = %d    num_descrs_needed = %d    num_descrs_avail = %d\n",
-		acd->mapped_entry_count, desc_needed, num_descrs_avail);
-
-	if (desc_needed >= ldev->desc_pool_cnt) {
-		dev_warn(&priv->ldev->pldev->dev,
-			 "    mapped_entry_count = %d    num_descrs_needed = %d    num_descrs_avail = %d    TOO MANY to ever complete!\n",
-			 acd->mapped_entry_count, desc_needed, num_descrs_avail);
-		rv = -EAGAIN;
-		goto err_descr_too_many;
-	}
-	if (desc_needed > num_descrs_avail) {
-		dev_warn(&priv->ldev->pldev->dev,
-			 "    mapped_entry_count = %d    num_descrs_needed = %d    num_descrs_avail = %d    Too many to complete right now.\n",
-			 acd->mapped_entry_count, desc_needed, num_descrs_avail);
-		rv = -EMSGSIZE;
-		goto err_descr_too_many;
-	}
-
-	// Loop through all the sg table entries and fill out a descriptor for each one.
-	desc = ldev->desc_next;
-	card_addr = acd->priv->card_addr;
-	for_each_sg(acd->sgt.sgl, sg, acd->mapped_entry_count, i) {
-		pcnt = count_parts_for_sge(sg);
-		for (p = 0 ; p < pcnt ; p++) {
-			// Fill out the descriptor
-			BUG_ON(!desc);
-			clear_desc(desc);
-			if (p != pcnt - 1)
-				desc->DescByteCount = 0x80000;
-			else
-				desc->DescByteCount = sg_dma_len(sg) - (p * 0x80000);
-
-			desc->DescBufferByteCount = desc->DescByteCount;
-
-			desc->DescControlFlags |= DMA_DESC_CTL_IRQONERR;
-			if (i == 0 && p == 0)
-				desc->DescControlFlags |= DMA_DESC_CTL_SOP;
-			if (i == acd->mapped_entry_count - 1 && p == pcnt - 1)
-				desc->DescControlFlags |= DMA_DESC_CTL_EOP | DMA_DESC_CTL_IRQONDONE;
-
-			desc->DescCardAddrLS = (card_addr & 0xFFFFFFFF);
-			desc->DescCardAddrMS = (card_addr >> 32) & 0xF;
-			card_addr += desc->DescByteCount;
-
-			dma_addr  = sg_dma_address(sg) + (p * 0x80000);
-			desc->DescSystemAddrLS = (dma_addr & 0x00000000FFFFFFFFUL) >>  0;
-			desc->DescSystemAddrMS = (dma_addr & 0xFFFFFFFF00000000UL) >> 32;
-
-			user_ctl = acd->priv->user_ctl;
-			if (i == acd->mapped_entry_count - 1 && p == pcnt - 1)
-				user_ctl = acd->priv->user_ctl_last;
-
-			desc->DescUserControlLS = (user_ctl & 0x00000000FFFFFFFFUL) >>  0;
-			desc->DescUserControlMS = (user_ctl & 0xFFFFFFFF00000000UL) >> 32;
-
-			if (i == acd->mapped_entry_count - 1 && p == pcnt - 1)
-				desc->acd = acd;
-
-			dev_dbg(&priv->ldev->pldev->dev, "  Filled descriptor %p (acd = %p)\n",
-				desc, desc->acd);
-
-			ldev->desc_next = desc->Next;
-			desc = desc->Next;
-		}
-	}
-
-	// Send the filled descriptors off to the hardware to process!
-	SetEngineSWPtr(ldev, ldev->desc_next);
-
-	unlock_engine(ldev);
-
-	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)
-		acd->cpl = NULL;
-	if (rv == 0) {
-		rv = acd->len;
-		kfree(acd);
-	}
-	return rv;
-
- err_descr_too_many:
-	unlock_engine(ldev);
-	dma_unmap_sg(&ldev->pldev->dev, acd->sgt.sgl, acd->sgt.nents, ldev->dir);
- free_table:
-	sg_free_table(&acd->sgt);
-
- unpin_pages:
-	if (nr_pages > 0)
-		unpin_user_pages(acd->user_pages, nr_pages);
-	kfree(acd->user_pages);
- err_alloc_userpages:
-	kfree(acd);
-	dev_dbg(&priv->ldev->pldev->dev, "%s returning with error %d\n", __func__, rv);
-	return rv;
-}
-
-void  transfer_complete_cb(struct aio_cb_data *acd, size_t xfr_count, u32 flags)
-{
-	unsigned int i;
-
-	BUG_ON(!acd);
-	BUG_ON(!acd->user_pages);
-	BUG_ON(!acd->sgt.sgl);
-	BUG_ON(!acd->ldev);
-	BUG_ON(!acd->ldev->pldev);
-
-	dma_unmap_sg(&acd->ldev->pldev->dev, acd->sgt.sgl, acd->sgt.nents, acd->ldev->dir);
-
-	for (i = 0 ; i < acd->page_count ; i++) {
-		if (!PageReserved(acd->user_pages[i]))
-			set_page_dirty_lock(acd->user_pages[i]);
-	}
-
-	unpin_user_pages(acd->user_pages, acd->page_count);
-
-	sg_free_table(&acd->sgt);
-
-	kfree(acd->user_pages);
-
-	acd->flags = flags;
-
-	if (acd->cpl) {
-		complete(acd->cpl);
-	} else {
-		/*
-		 * There's no completion, so we're responsible for cleaning up
-		 * the acd
-		 */
-		kfree(acd);
-	}
-}
-
-/**********  Fileops  **********/
-static
-int  kpc_dma_open(struct inode *inode, struct file *filp)
-{
-	struct dev_private_data *priv;
-	struct kpc_dma_device *ldev = kpc_dma_lookup_device(iminor(inode));
-
-	if (!ldev)
-		return -ENODEV;
-
-	if (!atomic_dec_and_test(&ldev->open_count)) {
-		atomic_inc(&ldev->open_count);
-		return -EBUSY; /* already open */
-	}
-
-	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
-	if (!priv)
-		return -ENOMEM;
-
-	priv->ldev = ldev;
-	filp->private_data = priv;
-
-	return 0;
-}
-
-static
-int  kpc_dma_close(struct inode *inode, struct file *filp)
-{
-	struct kpc_dma_descriptor *cur;
-	struct dev_private_data *priv = (struct dev_private_data *)filp->private_data;
-	struct kpc_dma_device *eng = priv->ldev;
-
-	lock_engine(eng);
-
-	stop_dma_engine(eng);
-
-	cur = eng->desc_completed->Next;
-	while (cur != eng->desc_next) {
-		dev_dbg(&eng->pldev->dev, "Aborting descriptor %p (acd = %p)\n", cur, cur->acd);
-		if (cur->DescControlFlags & DMA_DESC_CTL_EOP) {
-			if (cur->acd)
-				transfer_complete_cb(cur->acd, 0, ACD_FLAG_ABORT);
-		}
-
-		clear_desc(cur);
-		eng->desc_completed = cur;
-
-		cur = cur->Next;
-	}
-
-	start_dma_engine(eng);
-
-	unlock_engine(eng);
-
-	atomic_inc(&priv->ldev->open_count); /* release the device */
-	kfree(priv);
-	return 0;
-}
-
-static
-ssize_t  kpc_dma_read(struct file *filp,       char __user *user_buf, size_t count, loff_t *ppos)
-{
-	struct dev_private_data *priv = (struct dev_private_data *)filp->private_data;
-
-	if (priv->ldev->dir != DMA_FROM_DEVICE)
-		return -EMEDIUMTYPE;
-
-	return kpc_dma_transfer(priv, (unsigned long)user_buf, count);
-}
-
-static
-ssize_t  kpc_dma_write(struct file *filp, const char __user *user_buf, size_t count, loff_t *ppos)
-{
-	struct dev_private_data *priv = (struct dev_private_data *)filp->private_data;
-
-	if (priv->ldev->dir != DMA_TO_DEVICE)
-		return -EMEDIUMTYPE;
-
-	return kpc_dma_transfer(priv, (unsigned long)user_buf, count);
-}
-
-static
-long  kpc_dma_ioctl(struct file *filp, unsigned int ioctl_num, unsigned long ioctl_param)
-{
-	struct dev_private_data *priv = (struct dev_private_data *)filp->private_data;
-
-	switch (ioctl_num) {
-	case KND_IOCTL_SET_CARD_ADDR:
-		priv->card_addr  = ioctl_param; return priv->card_addr;
-	case KND_IOCTL_SET_USER_CTL:
-		priv->user_ctl   = ioctl_param; return priv->user_ctl;
-	case KND_IOCTL_SET_USER_CTL_LAST:
-		priv->user_ctl_last = ioctl_param; return priv->user_ctl_last;
-	case KND_IOCTL_GET_USER_STS:
-		return priv->user_sts;
-	}
-
-	return -ENOTTY;
-}
-
-const struct file_operations  kpc_dma_fops = {
-	.owner      = THIS_MODULE,
-	.open           = kpc_dma_open,
-	.release        = kpc_dma_close,
-	.read           = kpc_dma_read,
-	.write          = kpc_dma_write,
-	.unlocked_ioctl = kpc_dma_ioctl,
-};
-