drivers: most: add USB adapter driver

This patch adds the USB driver source file most_usb.c and
modifies the Makefile and Kconfig accordingly.

Signed-off-by: Christian Gromm <christian.gromm@microchip.com>
Link: https://lore.kernel.org/r/1596198058-26541-1-git-send-email-christian.gromm@microchip.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

4 files changed, 0 insertions, 1189 deletions

diff --git a/drivers/staging/most/Kconfig b/drivers/staging/most/Kconfig
index c5a99f750abe..c35fb34fae79 100644
--- a/drivers/staging/most/Kconfig
+++ b/drivers/staging/most/Kconfig
@@ -30,6 +30,4 @@ source "drivers/staging/most/dim2/Kconfig"
 
 source "drivers/staging/most/i2c/Kconfig"
 
-source "drivers/staging/most/usb/Kconfig"
-
 endif
diff --git a/drivers/staging/most/usb/Kconfig b/drivers/staging/most/usb/Kconfig
deleted file mode 100644
index a47a973dfb1d..000000000000
--- a/drivers/staging/most/usb/Kconfig
+++ /dev/null
@@ -1,13 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0
-#
-# MOST USB configuration
-#
-
-config MOST_USB
-	tristate "USB"
-	depends on USB
-	help
-	  Say Y here if you want to connect via USB to network transceiver.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called most_usb.
diff --git a/drivers/staging/most/usb/Makefile b/drivers/staging/most/usb/Makefile
deleted file mode 100644
index c2b207339aec..000000000000
--- a/drivers/staging/most/usb/Makefile
+++ /dev/null
@@ -1,4 +0,0 @@
-# SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_MOST_USB) += most_usb.o
-
-most_usb-objs := usb.o
diff --git a/drivers/staging/most/usb/usb.c b/drivers/staging/most/usb/usb.c
deleted file mode 100644
index 2640c5b326a4..000000000000
--- a/drivers/staging/most/usb/usb.c
+++ /dev/null
@@ -1,1170 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * usb.c - Hardware dependent module for USB
- *
- * Copyright (C) 2013-2015 Microchip Technology Germany II GmbH & Co. KG
- */
-
-#include <linux/module.h>
-#include <linux/fs.h>
-#include <linux/usb.h>
-#include <linux/slab.h>
-#include <linux/init.h>
-#include <linux/cdev.h>
-#include <linux/device.h>
-#include <linux/list.h>
-#include <linux/completion.h>
-#include <linux/mutex.h>
-#include <linux/spinlock.h>
-#include <linux/interrupt.h>
-#include <linux/workqueue.h>
-#include <linux/sysfs.h>
-#include <linux/dma-mapping.h>
-#include <linux/etherdevice.h>
-#include <linux/uaccess.h>
-#include <linux/most.h>
-
-#define USB_MTU			512
-#define NO_ISOCHRONOUS_URB	0
-#define AV_PACKETS_PER_XACT	2
-#define BUF_CHAIN_SIZE		0xFFFF
-#define MAX_NUM_ENDPOINTS	30
-#define MAX_SUFFIX_LEN		10
-#define MAX_STRING_LEN		80
-#define MAX_BUF_SIZE		0xFFFF
-
-#define USB_VENDOR_ID_SMSC	0x0424  /* VID: SMSC */
-#define USB_DEV_ID_BRDG		0xC001  /* PID: USB Bridge */
-#define USB_DEV_ID_OS81118	0xCF18  /* PID: USB OS81118 */
-#define USB_DEV_ID_OS81119	0xCF19  /* PID: USB OS81119 */
-#define USB_DEV_ID_OS81210	0xCF30  /* PID: USB OS81210 */
-/* DRCI Addresses */
-#define DRCI_REG_NI_STATE	0x0100
-#define DRCI_REG_PACKET_BW	0x0101
-#define DRCI_REG_NODE_ADDR	0x0102
-#define DRCI_REG_NODE_POS	0x0103
-#define DRCI_REG_MEP_FILTER	0x0140
-#define DRCI_REG_HASH_TBL0	0x0141
-#define DRCI_REG_HASH_TBL1	0x0142
-#define DRCI_REG_HASH_TBL2	0x0143
-#define DRCI_REG_HASH_TBL3	0x0144
-#define DRCI_REG_HW_ADDR_HI	0x0145
-#define DRCI_REG_HW_ADDR_MI	0x0146
-#define DRCI_REG_HW_ADDR_LO	0x0147
-#define DRCI_REG_BASE		0x1100
-#define DRCI_COMMAND		0x02
-#define DRCI_READ_REQ		0xA0
-#define DRCI_WRITE_REQ		0xA1
-
-/**
- * struct most_dci_obj - Direct Communication Interface
- * @kobj:position in sysfs
- * @usb_device: pointer to the usb device
- * @reg_addr: register address for arbitrary DCI access
- */
-struct most_dci_obj {
-	struct device dev;
-	struct usb_device *usb_device;
-	u16 reg_addr;
-};
-
-#define to_dci_obj(p) container_of(p, struct most_dci_obj, dev)
-
-struct most_dev;
-
-struct clear_hold_work {
-	struct work_struct ws;
-	struct most_dev *mdev;
-	unsigned int channel;
-	int pipe;
-};
-
-#define to_clear_hold_work(w) container_of(w, struct clear_hold_work, ws)
-
-/**
- * struct most_dev - holds all usb interface specific stuff
- * @usb_device: pointer to usb device
- * @iface: hardware interface
- * @cap: channel capabilities
- * @conf: channel configuration
- * @dci: direct communication interface of hardware
- * @ep_address: endpoint address table
- * @description: device description
- * @suffix: suffix for channel name
- * @channel_lock: synchronize channel access
- * @padding_active: indicates channel uses padding
- * @is_channel_healthy: health status table of each channel
- * @busy_urbs: list of anchored items
- * @io_mutex: synchronize I/O with disconnect
- * @link_stat_timer: timer for link status reports
- * @poll_work_obj: work for polling link status
- */
-struct most_dev {
-	struct device dev;
-	struct usb_device *usb_device;
-	struct most_interface iface;
-	struct most_channel_capability *cap;
-	struct most_channel_config *conf;
-	struct most_dci_obj *dci;
-	u8 *ep_address;
-	char description[MAX_STRING_LEN];
-	char suffix[MAX_NUM_ENDPOINTS][MAX_SUFFIX_LEN];
-	spinlock_t channel_lock[MAX_NUM_ENDPOINTS]; /* sync channel access */
-	bool padding_active[MAX_NUM_ENDPOINTS];
-	bool is_channel_healthy[MAX_NUM_ENDPOINTS];
-	struct clear_hold_work clear_work[MAX_NUM_ENDPOINTS];
-	struct usb_anchor *busy_urbs;
-	struct mutex io_mutex;
-	struct timer_list link_stat_timer;
-	struct work_struct poll_work_obj;
-	void (*on_netinfo)(struct most_interface *most_iface,
-			   unsigned char link_state, unsigned char *addrs);
-};
-
-#define to_mdev(d) container_of(d, struct most_dev, iface)
-#define to_mdev_from_dev(d) container_of(d, struct most_dev, dev)
-#define to_mdev_from_work(w) container_of(w, struct most_dev, poll_work_obj)
-
-static void wq_clear_halt(struct work_struct *wq_obj);
-static void wq_netinfo(struct work_struct *wq_obj);
-
-/**
- * drci_rd_reg - read a DCI register
- * @dev: usb device
- * @reg: register address
- * @buf: buffer to store data
- *
- * This is reads data from INIC's direct register communication interface
- */
-static inline int drci_rd_reg(struct usb_device *dev, u16 reg, u16 *buf)
-{
-	int retval;
-	__le16 *dma_buf;
-	u8 req_type = USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE;
-
-	dma_buf = kzalloc(sizeof(*dma_buf), GFP_KERNEL);
-	if (!dma_buf)
-		return -ENOMEM;
-
-	retval = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
-				 DRCI_READ_REQ, req_type,
-				 0x0000,
-				 reg, dma_buf, sizeof(*dma_buf), 5 * HZ);
-	*buf = le16_to_cpu(*dma_buf);
-	kfree(dma_buf);
-
-	if (retval < 0)
-		return retval;
-	return 0;
-}
-
-/**
- * drci_wr_reg - write a DCI register
- * @dev: usb device
- * @reg: register address
- * @data: data to write
- *
- * This is writes data to INIC's direct register communication interface
- */
-static inline int drci_wr_reg(struct usb_device *dev, u16 reg, u16 data)
-{
-	return usb_control_msg(dev,
-			       usb_sndctrlpipe(dev, 0),
-			       DRCI_WRITE_REQ,
-			       USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
-			       data,
-			       reg,
-			       NULL,
-			       0,
-			       5 * HZ);
-}
-
-static inline int start_sync_ep(struct usb_device *usb_dev, u16 ep)
-{
-	return drci_wr_reg(usb_dev, DRCI_REG_BASE + DRCI_COMMAND + ep * 16, 1);
-}
-
-/**
- * get_stream_frame_size - calculate frame size of current configuration
- * @dev: device structure
- * @cfg: channel configuration
- */
-static unsigned int get_stream_frame_size(struct device *dev,
-					  struct most_channel_config *cfg)
-{
-	unsigned int frame_size;
-	unsigned int sub_size = cfg->subbuffer_size;
-
-	if (!sub_size) {
-		dev_warn(dev, "Misconfig: Subbuffer size zero.\n");
-		return 0;
-	}
-	switch (cfg->data_type) {
-	case MOST_CH_ISOC:
-		frame_size = AV_PACKETS_PER_XACT * sub_size;
-		break;
-	case MOST_CH_SYNC:
-		if (cfg->packets_per_xact == 0) {
-			dev_warn(dev, "Misconfig: Packets per XACT zero\n");
-			frame_size = 0;
-		} else if (cfg->packets_per_xact == 0xFF) {
-			frame_size = (USB_MTU / sub_size) * sub_size;
-		} else {
-			frame_size = cfg->packets_per_xact * sub_size;
-		}
-		break;
-	default:
-		dev_warn(dev, "Query frame size of non-streaming channel\n");
-		frame_size = 0;
-		break;
-	}
-	return frame_size;
-}
-
-/**
- * hdm_poison_channel - mark buffers of this channel as invalid
- * @iface: pointer to the interface
- * @channel: channel ID
- *
- * This unlinks all URBs submitted to the HCD,
- * calls the associated completion function of the core and removes
- * them from the list.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int hdm_poison_channel(struct most_interface *iface, int channel)
-{
-	struct most_dev *mdev = to_mdev(iface);
-	unsigned long flags;
-	spinlock_t *lock; /* temp. lock */
-
-	if (channel < 0 || channel >= iface->num_channels) {
-		dev_warn(&mdev->usb_device->dev, "Channel ID out of range.\n");
-		return -ECHRNG;
-	}
-
-	lock = mdev->channel_lock + channel;
-	spin_lock_irqsave(lock, flags);
-	mdev->is_channel_healthy[channel] = false;
-	spin_unlock_irqrestore(lock, flags);
-
-	cancel_work_sync(&mdev->clear_work[channel].ws);
-
-	mutex_lock(&mdev->io_mutex);
-	usb_kill_anchored_urbs(&mdev->busy_urbs[channel]);
-	if (mdev->padding_active[channel])
-		mdev->padding_active[channel] = false;
-
-	if (mdev->conf[channel].data_type == MOST_CH_ASYNC) {
-		del_timer_sync(&mdev->link_stat_timer);
-		cancel_work_sync(&mdev->poll_work_obj);
-	}
-	mutex_unlock(&mdev->io_mutex);
-	return 0;
-}
-
-/**
- * hdm_add_padding - add padding bytes
- * @mdev: most device
- * @channel: channel ID
- * @mbo: buffer object
- *
- * This inserts the INIC hardware specific padding bytes into a streaming
- * channel's buffer
- */
-static int hdm_add_padding(struct most_dev *mdev, int channel, struct mbo *mbo)
-{
-	struct most_channel_config *conf = &mdev->conf[channel];
-	unsigned int frame_size = get_stream_frame_size(&mdev->dev, conf);
-	unsigned int j, num_frames;
-
-	if (!frame_size)
-		return -EINVAL;
-	num_frames = mbo->buffer_length / frame_size;
-
-	if (num_frames < 1) {
-		dev_err(&mdev->usb_device->dev,
-			"Missed minimal transfer unit.\n");
-		return -EINVAL;
-	}
-
-	for (j = num_frames - 1; j > 0; j--)
-		memmove(mbo->virt_address + j * USB_MTU,
-			mbo->virt_address + j * frame_size,
-			frame_size);
-	mbo->buffer_length = num_frames * USB_MTU;
-	return 0;
-}
-
-/**
- * hdm_remove_padding - remove padding bytes
- * @mdev: most device
- * @channel: channel ID
- * @mbo: buffer object
- *
- * This takes the INIC hardware specific padding bytes off a streaming
- * channel's buffer.
- */
-static int hdm_remove_padding(struct most_dev *mdev, int channel,
-			      struct mbo *mbo)
-{
-	struct most_channel_config *const conf = &mdev->conf[channel];
-	unsigned int frame_size = get_stream_frame_size(&mdev->dev, conf);
-	unsigned int j, num_frames;
-
-	if (!frame_size)
-		return -EINVAL;
-	num_frames = mbo->processed_length / USB_MTU;
-
-	for (j = 1; j < num_frames; j++)
-		memmove(mbo->virt_address + frame_size * j,
-			mbo->virt_address + USB_MTU * j,
-			frame_size);
-
-	mbo->processed_length = frame_size * num_frames;
-	return 0;
-}
-
-/**
- * hdm_write_completion - completion function for submitted Tx URBs
- * @urb: the URB that has been completed
- *
- * This checks the status of the completed URB. In case the URB has been
- * unlinked before, it is immediately freed. On any other error the MBO
- * transfer flag is set. On success it frees allocated resources and calls
- * the completion function.
- *
- * Context: interrupt!
- */
-static void hdm_write_completion(struct urb *urb)
-{
-	struct mbo *mbo = urb->context;
-	struct most_dev *mdev = to_mdev(mbo->ifp);
-	unsigned int channel = mbo->hdm_channel_id;
-	spinlock_t *lock = mdev->channel_lock + channel;
-	unsigned long flags;
-
-	spin_lock_irqsave(lock, flags);
-
-	mbo->processed_length = 0;
-	mbo->status = MBO_E_INVAL;
-	if (likely(mdev->is_channel_healthy[channel])) {
-		switch (urb->status) {
-		case 0:
-		case -ESHUTDOWN:
-			mbo->processed_length = urb->actual_length;
-			mbo->status = MBO_SUCCESS;
-			break;
-		case -EPIPE:
-			dev_warn(&mdev->usb_device->dev,
-				 "Broken pipe on ep%02x\n",
-				 mdev->ep_address[channel]);
-			mdev->is_channel_healthy[channel] = false;
-			mdev->clear_work[channel].pipe = urb->pipe;
-			schedule_work(&mdev->clear_work[channel].ws);
-			break;
-		case -ENODEV:
-		case -EPROTO:
-			mbo->status = MBO_E_CLOSE;
-			break;
-		}
-	}
-
-	spin_unlock_irqrestore(lock, flags);
-
-	if (likely(mbo->complete))
-		mbo->complete(mbo);
-	usb_free_urb(urb);
-}
-
-/**
- * hdm_read_completion - completion function for submitted Rx URBs
- * @urb: the URB that has been completed
- *
- * This checks the status of the completed URB. In case the URB has been
- * unlinked before it is immediately freed. On any other error the MBO transfer
- * flag is set. On success it frees allocated resources, removes
- * padding bytes -if necessary- and calls the completion function.
- *
- * Context: interrupt!
- */
-static void hdm_read_completion(struct urb *urb)
-{
-	struct mbo *mbo = urb->context;
-	struct most_dev *mdev = to_mdev(mbo->ifp);
-	unsigned int channel = mbo->hdm_channel_id;
-	struct device *dev = &mdev->usb_device->dev;
-	spinlock_t *lock = mdev->channel_lock + channel;
-	unsigned long flags;
-
-	spin_lock_irqsave(lock, flags);
-
-	mbo->processed_length = 0;
-	mbo->status = MBO_E_INVAL;
-	if (likely(mdev->is_channel_healthy[channel])) {
-		switch (urb->status) {
-		case 0:
-		case -ESHUTDOWN:
-			mbo->processed_length = urb->actual_length;
-			mbo->status = MBO_SUCCESS;
-			if (mdev->padding_active[channel] &&
-			    hdm_remove_padding(mdev, channel, mbo)) {
-				mbo->processed_length = 0;
-				mbo->status = MBO_E_INVAL;
-			}
-			break;
-		case -EPIPE:
-			dev_warn(dev, "Broken pipe on ep%02x\n",
-				 mdev->ep_address[channel]);
-			mdev->is_channel_healthy[channel] = false;
-			mdev->clear_work[channel].pipe = urb->pipe;
-			schedule_work(&mdev->clear_work[channel].ws);
-			break;
-		case -ENODEV:
-		case -EPROTO:
-			mbo->status = MBO_E_CLOSE;
-			break;
-		case -EOVERFLOW:
-			dev_warn(dev, "Babble on ep%02x\n",
-				 mdev->ep_address[channel]);
-			break;
-		}
-	}
-
-	spin_unlock_irqrestore(lock, flags);
-
-	if (likely(mbo->complete))
-		mbo->complete(mbo);
-	usb_free_urb(urb);
-}
-
-/**
- * hdm_enqueue - receive a buffer to be used for data transfer
- * @iface: interface to enqueue to
- * @channel: ID of the channel
- * @mbo: pointer to the buffer object
- *
- * This allocates a new URB and fills it according to the channel
- * that is being used for transmission of data. Before the URB is
- * submitted it is stored in the private anchor list.
- *
- * Returns 0 on success. On any error the URB is freed and a error code
- * is returned.
- *
- * Context: Could in _some_ cases be interrupt!
- */
-static int hdm_enqueue(struct most_interface *iface, int channel,
-		       struct mbo *mbo)
-{
-	struct most_dev *mdev = to_mdev(iface);
-	struct most_channel_config *conf;
-	int retval = 0;
-	struct urb *urb;
-	unsigned long length;
-	void *virt_address;
-
-	if (!mbo)
-		return -EINVAL;
-	if (iface->num_channels <= channel || channel < 0)
-		return -ECHRNG;
-
-	urb = usb_alloc_urb(NO_ISOCHRONOUS_URB, GFP_KERNEL);
-	if (!urb)
-		return -ENOMEM;
-
-	conf = &mdev->conf[channel];
-
-	mutex_lock(&mdev->io_mutex);
-	if (!mdev->usb_device) {
-		retval = -ENODEV;
-		goto err_free_urb;
-	}
-
-	if ((conf->direction & MOST_CH_TX) && mdev->padding_active[channel] &&
-	    hdm_add_padding(mdev, channel, mbo)) {
-		retval = -EINVAL;
-		goto err_free_urb;
-	}
-
-	urb->transfer_dma = mbo->bus_address;
-	virt_address = mbo->virt_address;
-	length = mbo->buffer_length;
-
-	if (conf->direction & MOST_CH_TX) {
-		usb_fill_bulk_urb(urb, mdev->usb_device,
-				  usb_sndbulkpipe(mdev->usb_device,
-						  mdev->ep_address[channel]),
-				  virt_address,
-				  length,
-				  hdm_write_completion,
-				  mbo);
-		if (conf->data_type != MOST_CH_ISOC &&
-		    conf->data_type != MOST_CH_SYNC)
-			urb->transfer_flags |= URB_ZERO_PACKET;
-	} else {
-		usb_fill_bulk_urb(urb, mdev->usb_device,
-				  usb_rcvbulkpipe(mdev->usb_device,
-						  mdev->ep_address[channel]),
-				  virt_address,
-				  length + conf->extra_len,
-				  hdm_read_completion,
-				  mbo);
-	}
-	urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
-
-	usb_anchor_urb(urb, &mdev->busy_urbs[channel]);
-
-	retval = usb_submit_urb(urb, GFP_KERNEL);
-	if (retval) {
-		dev_err(&mdev->usb_device->dev,
-			"URB submit failed with error %d.\n", retval);
-		goto err_unanchor_urb;
-	}
-	mutex_unlock(&mdev->io_mutex);
-	return 0;
-
-err_unanchor_urb:
-	usb_unanchor_urb(urb);
-err_free_urb:
-	usb_free_urb(urb);
-	mutex_unlock(&mdev->io_mutex);
-	return retval;
-}
-
-static void *hdm_dma_alloc(struct mbo *mbo, u32 size)
-{
-	struct most_dev *mdev = to_mdev(mbo->ifp);
-
-	return usb_alloc_coherent(mdev->usb_device, size, GFP_KERNEL,
-				  &mbo->bus_address);
-}
-
-static void hdm_dma_free(struct mbo *mbo, u32 size)
-{
-	struct most_dev *mdev = to_mdev(mbo->ifp);
-
-	usb_free_coherent(mdev->usb_device, size, mbo->virt_address,
-			  mbo->bus_address);
-}
-
-/**
- * hdm_configure_channel - receive channel configuration from core
- * @iface: interface
- * @channel: channel ID
- * @conf: structure that holds the configuration information
- *
- * The attached network interface controller (NIC) supports a padding mode
- * to avoid short packets on USB, hence increasing the performance due to a
- * lower interrupt load. This mode is default for synchronous data and can
- * be switched on for isochronous data. In case padding is active the
- * driver needs to know the frame size of the payload in order to calculate
- * the number of bytes it needs to pad when transmitting or to cut off when
- * receiving data.
- *
- */
-static int hdm_configure_channel(struct most_interface *iface, int channel,
-				 struct most_channel_config *conf)
-{
-	unsigned int num_frames;
-	unsigned int frame_size;
-	struct most_dev *mdev = to_mdev(iface);
-	struct device *dev = &mdev->usb_device->dev;
-
-	if (!conf) {
-		dev_err(dev, "Bad config pointer.\n");
-		return -EINVAL;
-	}
-	if (channel < 0 || channel >= iface->num_channels) {
-		dev_err(dev, "Channel ID out of range.\n");
-		return -EINVAL;
-	}
-
-	mdev->is_channel_healthy[channel] = true;
-	mdev->clear_work[channel].channel = channel;
-	mdev->clear_work[channel].mdev = mdev;
-	INIT_WORK(&mdev->clear_work[channel].ws, wq_clear_halt);
-
-	if (!conf->num_buffers || !conf->buffer_size) {
-		dev_err(dev, "Misconfig: buffer size or #buffers zero.\n");
-		return -EINVAL;
-	}
-
-	if (conf->data_type != MOST_CH_SYNC &&
-	    !(conf->data_type == MOST_CH_ISOC &&
-	      conf->packets_per_xact != 0xFF)) {
-		mdev->padding_active[channel] = false;
-		/*
-		 * Since the NIC's padding mode is not going to be
-		 * used, we can skip the frame size calculations and
-		 * move directly on to exit.
-		 */
-		goto exit;
-	}
-
-	mdev->padding_active[channel] = true;
-
-	frame_size = get_stream_frame_size(&mdev->dev, conf);
-	if (frame_size == 0 || frame_size > USB_MTU) {
-		dev_warn(dev, "Misconfig: frame size wrong\n");
-		return -EINVAL;
-	}
-
-	num_frames = conf->buffer_size / frame_size;
-
-	if (conf->buffer_size % frame_size) {
-		u16 old_size = conf->buffer_size;
-
-		conf->buffer_size = num_frames * frame_size;
-		dev_warn(dev, "%s: fixed buffer size (%d -> %d)\n",
-			 mdev->suffix[channel], old_size, conf->buffer_size);
-	}
-
-	/* calculate extra length to comply w/ HW padding */
-	conf->extra_len = num_frames * (USB_MTU - frame_size);
-
-exit:
-	mdev->conf[channel] = *conf;
-	if (conf->data_type == MOST_CH_ASYNC) {
-		u16 ep = mdev->ep_address[channel];
-
-		if (start_sync_ep(mdev->usb_device, ep) < 0)
-			dev_warn(dev, "sync for ep%02x failed", ep);
-	}
-	return 0;
-}
-
-/**
- * hdm_request_netinfo - request network information
- * @iface: pointer to interface
- * @channel: channel ID
- *
- * This is used as trigger to set up the link status timer that
- * polls for the NI state of the INIC every 2 seconds.
- *
- */
-static void hdm_request_netinfo(struct most_interface *iface, int channel,
-				void (*on_netinfo)(struct most_interface *,
-						   unsigned char,
-						   unsigned char *))
-{
-	struct most_dev *mdev = to_mdev(iface);
-
-	mdev->on_netinfo = on_netinfo;
-	if (!on_netinfo)
-		return;
-
-	mdev->link_stat_timer.expires = jiffies + HZ;
-	mod_timer(&mdev->link_stat_timer, mdev->link_stat_timer.expires);
-}
-
-/**
- * link_stat_timer_handler - schedule work obtaining mac address and link status
- * @data: pointer to USB device instance
- *
- * The handler runs in interrupt context. That's why we need to defer the
- * tasks to a work queue.
- */
-static void link_stat_timer_handler(struct timer_list *t)
-{
-	struct most_dev *mdev = from_timer(mdev, t, link_stat_timer);
-
-	schedule_work(&mdev->poll_work_obj);
-	mdev->link_stat_timer.expires = jiffies + (2 * HZ);
-	add_timer(&mdev->link_stat_timer);
-}
-
-/**
- * wq_netinfo - work queue function to deliver latest networking information
- * @wq_obj: object that holds data for our deferred work to do
- *
- * This retrieves the network interface status of the USB INIC
- */
-static void wq_netinfo(struct work_struct *wq_obj)
-{
-	struct most_dev *mdev = to_mdev_from_work(wq_obj);
-	struct usb_device *usb_device = mdev->usb_device;
-	struct device *dev = &usb_device->dev;
-	u16 hi, mi, lo, link;
-	u8 hw_addr[6];
-
-	if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_HI, &hi)) {
-		dev_err(dev, "Vendor request 'hw_addr_hi' failed\n");
-		return;
-	}
-
-	if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_MI, &mi)) {
-		dev_err(dev, "Vendor request 'hw_addr_mid' failed\n");
-		return;
-	}
-
-	if (drci_rd_reg(usb_device, DRCI_REG_HW_ADDR_LO, &lo)) {
-		dev_err(dev, "Vendor request 'hw_addr_low' failed\n");
-		return;
-	}
-
-	if (drci_rd_reg(usb_device, DRCI_REG_NI_STATE, &link)) {
-		dev_err(dev, "Vendor request 'link status' failed\n");
-		return;
-	}
-
-	hw_addr[0] = hi >> 8;
-	hw_addr[1] = hi;
-	hw_addr[2] = mi >> 8;
-	hw_addr[3] = mi;
-	hw_addr[4] = lo >> 8;
-	hw_addr[5] = lo;
-
-	if (mdev->on_netinfo)
-		mdev->on_netinfo(&mdev->iface, link, hw_addr);
-}
-
-/**
- * wq_clear_halt - work queue function
- * @wq_obj: work_struct object to execute
- *
- * This sends a clear_halt to the given USB pipe.
- */
-static void wq_clear_halt(struct work_struct *wq_obj)
-{
-	struct clear_hold_work *clear_work = to_clear_hold_work(wq_obj);
-	struct most_dev *mdev = clear_work->mdev;
-	unsigned int channel = clear_work->channel;
-	int pipe = clear_work->pipe;
-	int snd_pipe;
-	int peer;
-
-	mutex_lock(&mdev->io_mutex);
-	most_stop_enqueue(&mdev->iface, channel);
-	usb_kill_anchored_urbs(&mdev->busy_urbs[channel]);
-	if (usb_clear_halt(mdev->usb_device, pipe))
-		dev_warn(&mdev->usb_device->dev, "Failed to reset endpoint.\n");
-
-	/* If the functional Stall condition has been set on an
-	 * asynchronous rx channel, we need to clear the tx channel
-	 * too, since the hardware runs its clean-up sequence on both
-	 * channels, as they are physically one on the network.
-	 *
-	 * The USB interface that exposes the asynchronous channels
-	 * contains always two endpoints, and two only.
-	 */
-	if (mdev->conf[channel].data_type == MOST_CH_ASYNC &&
-	    mdev->conf[channel].direction == MOST_CH_RX) {
-		if (channel == 0)
-			peer = 1;
-		else
-			peer = 0;
-		snd_pipe = usb_sndbulkpipe(mdev->usb_device,
-					   mdev->ep_address[peer]);
-		usb_clear_halt(mdev->usb_device, snd_pipe);
-	}
-	mdev->is_channel_healthy[channel] = true;
-	most_resume_enqueue(&mdev->iface, channel);
-	mutex_unlock(&mdev->io_mutex);
-}
-
-/**
- * hdm_usb_fops - file operation table for USB driver
- */
-static const struct file_operations hdm_usb_fops = {
-	.owner = THIS_MODULE,
-};
-
-/**
- * usb_device_id - ID table for HCD device probing
- */
-static const struct usb_device_id usbid[] = {
-	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_BRDG), },
-	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81118), },
-	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81119), },
-	{ USB_DEVICE(USB_VENDOR_ID_SMSC, USB_DEV_ID_OS81210), },
-	{ } /* Terminating entry */
-};
-
-struct regs {
-	const char *name;
-	u16 reg;
-};
-
-static const struct regs ro_regs[] = {
-	{ "ni_state", DRCI_REG_NI_STATE },
-	{ "packet_bandwidth", DRCI_REG_PACKET_BW },
-	{ "node_address", DRCI_REG_NODE_ADDR },
-	{ "node_position", DRCI_REG_NODE_POS },
-};
-
-static const struct regs rw_regs[] = {
-	{ "mep_filter", DRCI_REG_MEP_FILTER },
-	{ "mep_hash0", DRCI_REG_HASH_TBL0 },
-	{ "mep_hash1", DRCI_REG_HASH_TBL1 },
-	{ "mep_hash2", DRCI_REG_HASH_TBL2 },
-	{ "mep_hash3", DRCI_REG_HASH_TBL3 },
-	{ "mep_eui48_hi", DRCI_REG_HW_ADDR_HI },
-	{ "mep_eui48_mi", DRCI_REG_HW_ADDR_MI },
-	{ "mep_eui48_lo", DRCI_REG_HW_ADDR_LO },
-};
-
-static int get_stat_reg_addr(const struct regs *regs, int size,
-			     const char *name, u16 *reg_addr)
-{
-	int i;
-
-	for (i = 0; i < size; i++) {
-		if (sysfs_streq(name, regs[i].name)) {
-			*reg_addr = regs[i].reg;
-			return 0;
-		}
-	}
-	return -EINVAL;
-}
-
-#define get_static_reg_addr(regs, name, reg_addr) \
-	get_stat_reg_addr(regs, ARRAY_SIZE(regs), name, reg_addr)
-
-static ssize_t value_show(struct device *dev, struct device_attribute *attr,
-			  char *buf)
-{
-	const char *name = attr->attr.name;
-	struct most_dci_obj *dci_obj = to_dci_obj(dev);
-	u16 val;
-	u16 reg_addr;
-	int err;
-
-	if (sysfs_streq(name, "arb_address"))
-		return snprintf(buf, PAGE_SIZE, "%04x\n", dci_obj->reg_addr);
-
-	if (sysfs_streq(name, "arb_value"))
-		reg_addr = dci_obj->reg_addr;
-	else if (get_static_reg_addr(ro_regs, name, &reg_addr) &&
-		 get_static_reg_addr(rw_regs, name, &reg_addr))
-		return -EINVAL;
-
-	err = drci_rd_reg(dci_obj->usb_device, reg_addr, &val);
-	if (err < 0)
-		return err;
-
-	return snprintf(buf, PAGE_SIZE, "%04x\n", val);
-}
-
-static ssize_t value_store(struct device *dev, struct device_attribute *attr,
-			   const char *buf, size_t count)
-{
-	u16 val;
-	u16 reg_addr;
-	const char *name = attr->attr.name;
-	struct most_dci_obj *dci_obj = to_dci_obj(dev);
-	struct usb_device *usb_dev = dci_obj->usb_device;
-	int err;
-
-	err = kstrtou16(buf, 16, &val);
-	if (err)
-		return err;
-
-	if (sysfs_streq(name, "arb_address")) {
-		dci_obj->reg_addr = val;
-		return count;
-	}
-
-	if (sysfs_streq(name, "arb_value"))
-		err = drci_wr_reg(usb_dev, dci_obj->reg_addr, val);
-	else if (sysfs_streq(name, "sync_ep"))
-		err = start_sync_ep(usb_dev, val);
-	else if (!get_static_reg_addr(rw_regs, name, &reg_addr))
-		err = drci_wr_reg(usb_dev, reg_addr, val);
-	else
-		return -EINVAL;
-
-	if (err < 0)
-		return err;
-
-	return count;
-}
-
-static DEVICE_ATTR(ni_state, 0444, value_show, NULL);
-static DEVICE_ATTR(packet_bandwidth, 0444, value_show, NULL);
-static DEVICE_ATTR(node_address, 0444, value_show, NULL);
-static DEVICE_ATTR(node_position, 0444, value_show, NULL);
-static DEVICE_ATTR(sync_ep, 0200, NULL, value_store);
-static DEVICE_ATTR(mep_filter, 0644, value_show, value_store);
-static DEVICE_ATTR(mep_hash0, 0644, value_show, value_store);
-static DEVICE_ATTR(mep_hash1, 0644, value_show, value_store);
-static DEVICE_ATTR(mep_hash2, 0644, value_show, value_store);
-static DEVICE_ATTR(mep_hash3, 0644, value_show, value_store);
-static DEVICE_ATTR(mep_eui48_hi, 0644, value_show, value_store);
-static DEVICE_ATTR(mep_eui48_mi, 0644, value_show, value_store);
-static DEVICE_ATTR(mep_eui48_lo, 0644, value_show, value_store);
-static DEVICE_ATTR(arb_address, 0644, value_show, value_store);
-static DEVICE_ATTR(arb_value, 0644, value_show, value_store);
-
-static struct attribute *dci_attrs[] = {
-	&dev_attr_ni_state.attr,
-	&dev_attr_packet_bandwidth.attr,
-	&dev_attr_node_address.attr,
-	&dev_attr_node_position.attr,
-	&dev_attr_sync_ep.attr,
-	&dev_attr_mep_filter.attr,
-	&dev_attr_mep_hash0.attr,
-	&dev_attr_mep_hash1.attr,
-	&dev_attr_mep_hash2.attr,
-	&dev_attr_mep_hash3.attr,
-	&dev_attr_mep_eui48_hi.attr,
-	&dev_attr_mep_eui48_mi.attr,
-	&dev_attr_mep_eui48_lo.attr,
-	&dev_attr_arb_address.attr,
-	&dev_attr_arb_value.attr,
-	NULL,
-};
-
-ATTRIBUTE_GROUPS(dci);
-
-static void release_dci(struct device *dev)
-{
-	struct most_dci_obj *dci = to_dci_obj(dev);
-
-	put_device(dev->parent);
-	kfree(dci);
-}
-
-static void release_mdev(struct device *dev)
-{
-	struct most_dev *mdev = to_mdev_from_dev(dev);
-
-	kfree(mdev);
-}
-/**
- * hdm_probe - probe function of USB device driver
- * @interface: Interface of the attached USB device
- * @id: Pointer to the USB ID table.
- *
- * This allocates and initializes the device instance, adds the new
- * entry to the internal list, scans the USB descriptors and registers
- * the interface with the core.
- * Additionally, the DCI objects are created and the hardware is sync'd.
- *
- * Return 0 on success. In case of an error a negative number is returned.
- */
-static int
-hdm_probe(struct usb_interface *interface, const struct usb_device_id *id)
-{
-	struct usb_host_interface *usb_iface_desc = interface->cur_altsetting;
-	struct usb_device *usb_dev = interface_to_usbdev(interface);
-	struct device *dev = &usb_dev->dev;
-	struct most_dev *mdev;
-	unsigned int i;
-	unsigned int num_endpoints;
-	struct most_channel_capability *tmp_cap;
-	struct usb_endpoint_descriptor *ep_desc;
-	int ret = -ENOMEM;
-
-	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
-	if (!mdev)
-		return -ENOMEM;
-
-	usb_set_intfdata(interface, mdev);
-	num_endpoints = usb_iface_desc->desc.bNumEndpoints;
-	if (num_endpoints > MAX_NUM_ENDPOINTS) {
-		kfree(mdev);
-		return -EINVAL;
-	}
-	mutex_init(&mdev->io_mutex);
-	INIT_WORK(&mdev->poll_work_obj, wq_netinfo);
-	timer_setup(&mdev->link_stat_timer, link_stat_timer_handler, 0);
-
-	mdev->usb_device = usb_dev;
-	mdev->link_stat_timer.expires = jiffies + (2 * HZ);
-
-	mdev->iface.mod = hdm_usb_fops.owner;
-	mdev->iface.dev = &mdev->dev;
-	mdev->iface.driver_dev = &interface->dev;
-	mdev->iface.interface = ITYPE_USB;
-	mdev->iface.configure = hdm_configure_channel;
-	mdev->iface.request_netinfo = hdm_request_netinfo;
-	mdev->iface.enqueue = hdm_enqueue;
-	mdev->iface.poison_channel = hdm_poison_channel;
-	mdev->iface.dma_alloc = hdm_dma_alloc;
-	mdev->iface.dma_free = hdm_dma_free;
-	mdev->iface.description = mdev->description;
-	mdev->iface.num_channels = num_endpoints;
-
-	snprintf(mdev->description, sizeof(mdev->description),
-		 "%d-%s:%d.%d",
-		 usb_dev->bus->busnum,
-		 usb_dev->devpath,
-		 usb_dev->config->desc.bConfigurationValue,
-		 usb_iface_desc->desc.bInterfaceNumber);
-
-	mdev->dev.init_name = mdev->description;
-	mdev->dev.parent = &interface->dev;
-	mdev->dev.release = release_mdev;
-	mdev->conf = kcalloc(num_endpoints, sizeof(*mdev->conf), GFP_KERNEL);
-	if (!mdev->conf)
-		goto err_free_mdev;
-
-	mdev->cap = kcalloc(num_endpoints, sizeof(*mdev->cap), GFP_KERNEL);
-	if (!mdev->cap)
-		goto err_free_conf;
-
-	mdev->iface.channel_vector = mdev->cap;
-	mdev->ep_address =
-		kcalloc(num_endpoints, sizeof(*mdev->ep_address), GFP_KERNEL);
-	if (!mdev->ep_address)
-		goto err_free_cap;
-
-	mdev->busy_urbs =
-		kcalloc(num_endpoints, sizeof(*mdev->busy_urbs), GFP_KERNEL);
-	if (!mdev->busy_urbs)
-		goto err_free_ep_address;
-
-	tmp_cap = mdev->cap;
-	for (i = 0; i < num_endpoints; i++) {
-		ep_desc = &usb_iface_desc->endpoint[i].desc;
-		mdev->ep_address[i] = ep_desc->bEndpointAddress;
-		mdev->padding_active[i] = false;
-		mdev->is_channel_healthy[i] = true;
-
-		snprintf(&mdev->suffix[i][0], MAX_SUFFIX_LEN, "ep%02x",
-			 mdev->ep_address[i]);
-
-		tmp_cap->name_suffix = &mdev->suffix[i][0];
-		tmp_cap->buffer_size_packet = MAX_BUF_SIZE;
-		tmp_cap->buffer_size_streaming = MAX_BUF_SIZE;
-		tmp_cap->num_buffers_packet = BUF_CHAIN_SIZE;
-		tmp_cap->num_buffers_streaming = BUF_CHAIN_SIZE;
-		tmp_cap->data_type = MOST_CH_CONTROL | MOST_CH_ASYNC |
-				     MOST_CH_ISOC | MOST_CH_SYNC;
-		if (usb_endpoint_dir_in(ep_desc))
-			tmp_cap->direction = MOST_CH_RX;
-		else
-			tmp_cap->direction = MOST_CH_TX;
-		tmp_cap++;
-		init_usb_anchor(&mdev->busy_urbs[i]);
-		spin_lock_init(&mdev->channel_lock[i]);
-	}
-	dev_dbg(dev, "claimed gadget: Vendor=%4.4x ProdID=%4.4x Bus=%02x Device=%02x\n",
-		le16_to_cpu(usb_dev->descriptor.idVendor),
-		le16_to_cpu(usb_dev->descriptor.idProduct),
-		usb_dev->bus->busnum,
-		usb_dev->devnum);
-
-	dev_dbg(dev, "device path: /sys/bus/usb/devices/%d-%s:%d.%d\n",
-		usb_dev->bus->busnum,
-		usb_dev->devpath,
-		usb_dev->config->desc.bConfigurationValue,
-		usb_iface_desc->desc.bInterfaceNumber);
-
-	ret = most_register_interface(&mdev->iface);
-	if (ret)
-		goto err_free_busy_urbs;
-
-	mutex_lock(&mdev->io_mutex);
-	if (le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81118 ||
-	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81119 ||
-	    le16_to_cpu(usb_dev->descriptor.idProduct) == USB_DEV_ID_OS81210) {
-		mdev->dci = kzalloc(sizeof(*mdev->dci), GFP_KERNEL);
-		if (!mdev->dci) {
-			mutex_unlock(&mdev->io_mutex);
-			most_deregister_interface(&mdev->iface);
-			ret = -ENOMEM;
-			goto err_free_busy_urbs;
-		}
-
-		mdev->dci->dev.init_name = "dci";
-		mdev->dci->dev.parent = get_device(mdev->iface.dev);
-		mdev->dci->dev.groups = dci_groups;
-		mdev->dci->dev.release = release_dci;
-		if (device_register(&mdev->dci->dev)) {
-			mutex_unlock(&mdev->io_mutex);
-			most_deregister_interface(&mdev->iface);
-			ret = -ENOMEM;
-			goto err_free_dci;
-		}
-		mdev->dci->usb_device = mdev->usb_device;
-	}
-	mutex_unlock(&mdev->io_mutex);
-	return 0;
-err_free_dci:
-	put_device(&mdev->dci->dev);
-err_free_busy_urbs:
-	kfree(mdev->busy_urbs);
-err_free_ep_address:
-	kfree(mdev->ep_address);
-err_free_cap:
-	kfree(mdev->cap);
-err_free_conf:
-	kfree(mdev->conf);
-err_free_mdev:
-	put_device(&mdev->dev);
-	return ret;
-}
-
-/**
- * hdm_disconnect - disconnect function of USB device driver
- * @interface: Interface of the attached USB device
- *
- * This deregisters the interface with the core, removes the kernel timer
- * and frees resources.
- *
- * Context: hub kernel thread
- */
-static void hdm_disconnect(struct usb_interface *interface)
-{
-	struct most_dev *mdev = usb_get_intfdata(interface);
-
-	mutex_lock(&mdev->io_mutex);
-	usb_set_intfdata(interface, NULL);
-	mdev->usb_device = NULL;
-	mutex_unlock(&mdev->io_mutex);
-
-	del_timer_sync(&mdev->link_stat_timer);
-	cancel_work_sync(&mdev->poll_work_obj);
-
-	if (mdev->dci)
-		device_unregister(&mdev->dci->dev);
-	most_deregister_interface(&mdev->iface);
-
-	kfree(mdev->busy_urbs);
-	kfree(mdev->cap);
-	kfree(mdev->conf);
-	kfree(mdev->ep_address);
-	put_device(&mdev->dci->dev);
-	put_device(&mdev->dev);
-}
-
-static int hdm_suspend(struct usb_interface *interface, pm_message_t message)
-{
-	struct most_dev *mdev = usb_get_intfdata(interface);
-	int i;
-
-	mutex_lock(&mdev->io_mutex);
-	for (i = 0; i < mdev->iface.num_channels; i++) {
-		most_stop_enqueue(&mdev->iface, i);
-		usb_kill_anchored_urbs(&mdev->busy_urbs[i]);
-	}
-	mutex_unlock(&mdev->io_mutex);
-	return 0;
-}
-
-static int hdm_resume(struct usb_interface *interface)
-{
-	struct most_dev *mdev = usb_get_intfdata(interface);
-	int i;
-
-	mutex_lock(&mdev->io_mutex);
-	for (i = 0; i < mdev->iface.num_channels; i++)
-		most_resume_enqueue(&mdev->iface, i);
-	mutex_unlock(&mdev->io_mutex);
-	return 0;
-}
-
-static struct usb_driver hdm_usb = {
-	.name = "hdm_usb",
-	.id_table = usbid,
-	.probe = hdm_probe,
-	.disconnect = hdm_disconnect,
-	.resume = hdm_resume,
-	.suspend = hdm_suspend,
-};
-
-module_usb_driver(hdm_usb);
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Christian Gromm <christian.gromm@microchip.com>");
-MODULE_DESCRIPTION("HDM_4_USB");