path: root/drivers/usb/c67x00/c67x00-sched.c

/*
 * c67x00-sched.c: Cypress C67X00 USB Host Controller Driver - TD scheduling
 *
 * Copyright (C) 2006-2008 Barco N.V.
 *    Derived from the Cypress cy7c67200/300 ezusb linux driver and
 *    based on multiple host controller drivers inside the linux kernel.
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA  02110-1301  USA.
 */

#include <linux/kthread.h>

#include "c67x00.h"
#include "c67x00-hcd.h"

/*
 * These are the stages for a control urb, they are kept
 * in both urb->interval and td->privdata.
 */
#define SETUP_STAGE		0
#define DATA_STAGE		1
#define STATUS_STAGE		2

/* -------------------------------------------------------------------------- */

/**
 * struct c67x00_ep_data: Host endpoint data structure
 */
struct c67x00_ep_data {
	struct list_head queue;
	struct list_head node;
	struct usb_host_endpoint *hep;
	struct usb_device *dev;
	u16 next_frame;		/* For int/isoc transactions */
};

/**
 * struct c67x00_td
 *
 * Hardware parts are little endiannes, SW in CPU endianess.
 */
struct c67x00_td {
	/* HW specific part */
	__le16 ly_base_addr;	/* Bytes 0-1 */
	__le16 port_length;	/* Bytes 2-3 */
	u8 pid_ep;		/* Byte 4 */
	u8 dev_addr;		/* Byte 5 */
	u8 ctrl_reg;		/* Byte 6 */
	u8 status;		/* Byte 7 */
	u8 retry_cnt;		/* Byte 8 */
#define TT_OFFSET		2
#define TT_CONTROL		0
#define TT_ISOCHRONOUS		1
#define TT_BULK			2
#define TT_INTERRUPT		3
	u8 residue;		/* Byte 9 */
	__le16 next_td_addr;	/* Bytes 10-11 */
	/* SW part */
	struct list_head td_list;
	u16 td_addr;
	void *data;
	struct urb *urb;
	unsigned long privdata;

	/* These are needed for handling the toggle bits:
	 * an urb can be dequeued while a td is in progress
	 * after checking the td, the toggle bit might need to
	 * be fixed */
	struct c67x00_ep_data *ep_data;
	unsigned int pipe;
};

struct c67x00_urb_priv {
	struct list_head hep_node;
	struct urb *urb;
	int port;
	int cnt;		/* packet number for isoc */
	int status;
	struct c67x00_ep_data *ep_data;
};

#define td_udev(td)	((td)->ep_data->dev)

#define CY_TD_SIZE		12

#define TD_PIDEP_OFFSET		0x04
#define TD_PIDEPMASK_PID	0xF0
#define TD_PIDEPMASK_EP		0x0F
#define TD_PORTLENMASK_DL	0x02FF
#define TD_PORTLENMASK_PN	0xC000

#define TD_STATUS_OFFSET	0x07
#define TD_STATUSMASK_ACK	0x01
#define TD_STATUSMASK_ERR	0x02
#define TD_STATUSMASK_TMOUT	0x04
#define TD_STATUSMASK_SEQ	0x08
#define TD_STATUSMASK_SETUP	0x10
#define TD_STATUSMASK_OVF	0x20
#define TD_STATUSMASK_NAK	0x40
#define TD_STATUSMASK_STALL	0x80

#define TD_ERROR_MASK		(TD_STATUSMASK_ERR | TD_STATUSMASK_TMOUT | \
				 TD_STATUSMASK_STALL)

#define TD_RETRYCNT_OFFSET	0x08
#define TD_RETRYCNTMASK_ACT_FLG	0x10
#define TD_RETRYCNTMASK_TX_TYPE	0x0C
#define TD_RETRYCNTMASK_RTY_CNT	0x03

#define TD_RESIDUE_OVERFLOW	0x80

#define TD_PID_IN		0x90

/* Residue: signed 8bits, neg -> OVERFLOW, pos -> UNDERFLOW */
#define td_residue(td)		((__s8)(td->residue))
#define td_ly_base_addr(td)	(__le16_to_cpu((td)->ly_base_addr))
#define td_port_length(td)	(__le16_to_cpu((td)->port_length))
#define td_next_td_addr(td)	(__le16_to_cpu((td)->next_td_addr))

#define td_active(td)		((td)->retry_cnt & TD_RETRYCNTMASK_ACT_FLG)
#define td_length(td)		(td_port_length(td) & TD_PORTLENMASK_DL)

#define td_sequence_ok(td)	(!td->status || \
				 (!(td->status & TD_STATUSMASK_SEQ) ==	\
				  !(td->ctrl_reg & SEQ_SEL)))

#define td_acked(td)		(!td->status || \
				 (td->status & TD_STATUSMASK_ACK))
#define td_actual_bytes(td)	(td_length(td) - td_residue(td))

/* -------------------------------------------------------------------------- */

#ifdef DEBUG

/**
 * dbg_td - Dump the contents of the TD
 */
static void dbg_td(struct c67x00_hcd *c67x00, struct c67x00_td *td, char *msg)
{
	struct device *dev = c67x00_hcd_dev(c67x00);

	dev_dbg(dev, "### %s at 0x%04x\n", msg, td->td_addr);
	dev_dbg(dev, "urb:      0x%p\n", td->urb);
	dev_dbg(dev, "endpoint:   %4d\n", usb_pipeendpoint(td->pipe));
	dev_dbg(dev, "pipeout:    %4d\n", usb_pipeout(td->pipe));
	dev_dbg(dev, "ly_base_addr: 0x%04x\n", td_ly_base_addr(td));
	dev_dbg(dev, "port_length:  0x%04x\n", td_port_length(td));
	dev_dbg(dev, "pid_ep:         0x%02x\n", td->pid_ep);
	dev_dbg(dev, "dev_addr:       0x%02x\n", td->dev_addr);
	dev_dbg(dev, "ctrl_reg:       0x%02x\n", td->ctrl_reg);
	dev_dbg(dev, "status:         0x%02x\n", td