path: root/drivers/usb/gadget/udc/fusb300_udc.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Fusb300 UDC (USB gadget)
 *
 * Copyright (C) 2010 Faraday Technology Corp.
 *
 * Author : Yuan-hsin Chen <yhchen@faraday-tech.com>
 */
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>

#include "fusb300_udc.h"

MODULE_DESCRIPTION("FUSB300  USB gadget driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Yuan-Hsin Chen, Feng-Hsin Chiang <john453@faraday-tech.com>");
MODULE_ALIAS("platform:fusb300_udc");

#define DRIVER_VERSION	"20 October 2010"

static const char udc_name[] = "fusb300_udc";
static const char * const fusb300_ep_name[] = {
	"ep0", "ep1", "ep2", "ep3", "ep4", "ep5", "ep6", "ep7", "ep8", "ep9",
	"ep10", "ep11", "ep12", "ep13", "ep14", "ep15"
};

static void done(struct fusb300_ep *ep, struct fusb300_request *req,
		 int status);

static void fusb300_enable_bit(struct fusb300 *fusb300, u32 offset,
			       u32 value)
{
	u32 reg = ioread32(fusb300->reg + offset);

	reg |= value;
	iowrite32(reg, fusb300->reg + offset);
}

static void fusb300_disable_bit(struct fusb300 *fusb300, u32 offset,
				u32 value)
{
	u32 reg = ioread32(fusb300->reg + offset);

	reg &= ~value;
	iowrite32(reg, fusb300->reg + offset);
}


static void fusb300_ep_setting(struct fusb300_ep *ep,
			       struct fusb300_ep_info info)
{
	ep->epnum = info.epnum;
	ep->type = info.type;
}

static int fusb300_ep_release(struct fusb300_ep *ep)
{
	if (!ep->epnum)
		return 0;
	ep->epnum = 0;
	ep->stall = 0;
	ep->wedged = 0;
	return 0;
}

static void fusb300_set_fifo_entry(struct fusb300 *fusb300,
				   u32 ep)
{
	u32 val = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET1(ep));

	val &= ~FUSB300_EPSET1_FIFOENTRY_MSK;
	val |= FUSB300_EPSET1_FIFOENTRY(FUSB300_FIFO_ENTRY_NUM);
	iowrite32(val, fusb300->reg + FUSB300_OFFSET_EPSET1(ep));
}

static void fusb300_set_start_entry(struct fusb300 *fusb300,
				    u8 ep)
{
	u32 reg = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET1(ep));
	u32 start_entry = fusb300->fifo_entry_num * FUSB300_FIFO_ENTRY_NUM;

	reg &= ~FUSB300_EPSET1_START_ENTRY_MSK	;
	reg |= FUSB300_EPSET1_START_ENTRY(start_entry);
	iowrite32(reg, fusb300->reg + FUSB300_OFFSET_EPSET1(ep));
	if (fusb300->fifo_entry_num == FUSB300_MAX_FIFO_ENTRY) {
		fusb300->fifo_entry_num = 0;
		fusb300->addrofs = 0;
		pr_err("fifo entry is over the maximum number!\n");
	} else
		fusb300->fifo_entry_num++;
}

/* set fusb300_set_start_entry first before fusb300_set_epaddrofs */
static void fusb300_set_epaddrofs(struct fusb300 *fusb300,
				  struct fusb300_ep_info info)
{
	u32 reg = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET2(info.epnum));

	reg &= ~FUSB300_EPSET2_ADDROFS_MSK;
	reg |= FUSB300_EPSET2_ADDROFS(fusb300->addrofs);
	iowrite32(reg, fusb300->reg + FUSB300_OFFSET_EPSET2(info.epnum));
	fusb300->addrofs += (info.maxpacket + 7) / 8 * FUSB300_FIFO_ENTRY_NUM;
}

static void ep_fifo_setting(struct fusb300 *fusb300,
			    struct fusb300_ep_info info)
{
	fusb300_set_fifo_entry(fusb300, info.epnum);
	fusb300_set_start_entry(fusb300, info.epnum);
	fusb300_set_epaddrofs(fusb300, info);
}

static void fusb300_set_eptype(struct fusb300 *fusb300,
			       struct fusb300_ep_info info)
{
	u32 reg = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET1(info.epnum));

	reg &= ~FUSB300_EPSET1_TYPE_MSK;
	reg |= FUSB300_EPSET1_TYPE(info.type);
	iowrite32(reg, fusb300->reg + FUSB300_OFFSET_EPSET1(info.epnum));
}

static void fusb300_set_epdir(struct fusb300 *fusb300,
			      struct fusb300_ep_info info)
{
	u32 reg;

	if (!info.dir_in)
		return;
	reg = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET1(info.epnum));
	reg &= ~FUSB300_EPSET1_DIR_MSK;
	reg |= FUSB300_EPSET1_DIRIN;
	iowrite32(reg, fusb300->reg + FUSB300_OFFSET_EPSET1(info.epnum));
}

static void fusb300_set_ep_active(struct fusb300 *fusb300,
			  u8 ep)
{
	u32 reg = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET1(ep));

	reg |= FUSB300_EPSET1_ACTEN;
	iowrite32(reg, fusb300->reg + FUSB300_OFFSET_EPSET1(ep));
}

static void fusb300_set_epmps(struct fusb300 *fusb300,
			      struct fusb300_ep_info info)
{
	u32 reg = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET2(info.epnum));

	reg &= ~FUSB300_EPSET2_MPS_MSK;
	reg |= FUSB300_EPSET2_MPS(info.maxpacket);
	iowrite32(reg, fusb300->reg + FUSB300_OFFSET_EPSET2(info.epnum));
}

static void fusb300_set_interval(struct fusb300 *fusb300,
				 struct fusb300_ep_info info)
{
	u32 reg = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET1(info.epnum));

	reg &= ~FUSB300_EPSET1_INTERVAL(0x7);
	reg |= FUSB300_EPSET1_INTERVAL(info.interval);
	iowrite32(reg, fusb300->reg + FUSB300_OFFSET_EPSET1(info.epnum));
}

static void fusb300_set_bwnum(struct fusb300 *fusb300,
			      struct fusb300_ep_info info)
{
	u32 reg = ioread32(fusb300->reg + FUSB300_OFFSET_EPSET1(info.epnum));

	reg &= ~FUSB300_EPSET1_BWNUM(0x3);
	reg |= FUSB300_EPSET1_BWNUM(info.bw_num);
	iowrite32(reg, fusb300->reg + FUSB300_OFFSET_EPSET1(info.epnum));
}

static void set_ep_reg(struct fusb300 *fusb300,
		      struct fusb300_ep_info info)
{
	fusb300_set_eptype(fusb300, info);
	fusb300_set_epdir(fusb300, info);
	fusb300_set_epmps(fusb300, info);

	if (info.interval)
		fusb300_set_interval(fusb300, info);

	if (info.bw_num)
		fusb300_set_bwnum(fusb300, info);

	fusb300_set_ep_active(fusb300, info.epnum);
}

static int config_ep(struct fusb300_ep *ep,
		     const struct usb_endpoint_descriptor *desc)
{
	struct fusb300 *fusb300 = ep->fusb300;
	struct fusb300_ep_info info;

	ep->ep.desc = desc;

	info.interval = 0;
	info.addrofs = 0;
	info.bw_num = 0;

	info.type = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
	info.dir_in = (desc->bEndpointAddress & USB_ENDPOINT_DIR_MASK) ? 1 : 0;
	info.maxpacket = usb_endpoint_maxp(desc);
	info.epnum = desc->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;

	if ((info.type == USB_ENDPOINT_XFER_INT) ||
	   (info.type == USB_ENDPOINT_XFER_ISOC)) {
		info.interval = desc->bInterval;
		if (info.type == USB_ENDPOINT_XFER_ISOC)
			info.bw_num = usb_endpoint_maxp_mult(desc);
	}

	ep_fifo_setting(fusb300, info);

	set_ep_reg(fusb300, info);

	fusb300_ep_setting(ep, info);

	fusb300->ep[info.epnum] = ep;

	return 0;
}

static int fusb300_enable(struct usb_ep *_ep,
			  const struct usb_endpoint_descriptor *desc)
{
	struct fusb300_ep *ep;

	ep = container_of(_ep, struct fusb300_ep, ep);

	if (ep->fusb300->reenum) {
		ep->fusb300->fifo_entry_num = 0;
		ep->fusb300->addrofs = 0;
		ep->fusb300->reenum = 0;
	}

	return config_ep(ep, desc);
}

static int fusb300_disable(struct usb_ep *_ep)
{
	struct fusb300_ep *ep;
	struct fusb300_request *req;
	unsigned long flags;

	ep = container_of(_ep, struct fusb300_ep, ep);

	BUG_ON(!ep);

	while (!list_empty(&ep->queue)) {
		req = list_entry(ep->queue.next, struct fusb300_request, queue);
		spin_lock_irqsave(&ep->fusb300->lock, flags);
		done(ep, req, -ECONNRESET);
		spin_unlock_irqrestore(&ep->fusb300->lock, flags);
	}

	return fusb300_ep_release(ep);
}

static struct usb_request *fusb300_alloc_request(struct usb_ep *_ep,
						gfp_t gfp_flags)
{
	struct fusb300_request *req;

	req = kzalloc(sizeof(struct fusb300_request), gfp_flags);
	if (!req)
		return NULL;
	INIT_LIST_HEAD(&req->queue);

	return &req->req;
}

static void fusb300_free_request(struct usb_ep *_ep, struct usb_request *_req)
{
	struct fusb300_request *req;

	req = container_of(_req, struct fusb300_request, req);
	kfree(req);
}

static int enable_fifo_int(struct fusb300_ep *ep)
{
	struct fusb300 *fusb300 = ep->fusb300;

	if (ep->epnum) {
		fusb300_enable_bit(fusb300, FUSB300_OFFSET_IGER0,
			FUSB300_IGER0_EEPn_FIFO_INT(ep->epnum));
	} else {
		pr_err("can't enable_fifo_int ep0\n");
		return -EINVAL;
	}

	r