USB: net2272: driver for PLX NET2272 USB device controller

This is based on the last release from PLX:
	http://www.plxtech.com/files/products/net2000/software/selectiontool/RE061204-net2272-linux2.6.18.tgz

I've managed to contact them and they've confirmed that this driver was
wholly written by PLX (Seth Levy).  While they have no problem with it
being merged (and they've already licensed it as GPL), they don't have
any interest in doing so themselves as this is an old part for them.

ADI has long had an add-on card which has this part on it, so we've been
keeping it up-to-date out of tree.  But now that PLX has confirmed the
source of the driver, we can can take the next step of cleaning it up and
getting it merged.

So here we are!  I've done quite a large clean up of the driver and
attempted to address all the common issues.  Hopefully in the process,
I haven't broken anything.  While it seems to still work with the board
that I have access to, it is not a PCI variant.  So I have not tested
any of the PCI logic myself (beyond clean compile).  Perhaps someone who
actually has a card and cares can do so.

I'll try to address further feedback, but don't expect miracles.  I'm
not really familiar with the part itself, just the platform glue.

Signed-off-by: Seth Levy <seth.levy@plxtech.com>
Signed-off-by: Ash Aziz <ash.aziz@plxtech.com>
Signed-off-by: Roy Huang <roy.huang@analog.com>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 601 insertions, 0 deletions

diff --git a/drivers/usb/gadget/net2272.h b/drivers/usb/gadget/net2272.h
new file mode 100644
index 0000000..e595057
--- /dev/null
+++ b/drivers/usb/gadget/net2272.h
@@ -0,0 +1,601 @@
+/*
+ * PLX NET2272 high/full speed USB device controller
+ *
+ * Copyright (C) 2005-2006 PLX Technology, Inc.
+ * Copyright (C) 2006-2011 Analog Devices, Inc.
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef __NET2272_H__
+#define __NET2272_H__
+
+/* Main Registers */
+#define REGADDRPTR			0x00
+#define REGDATA				0x01
+#define IRQSTAT0			0x02
+#define 	ENDPOINT_0_INTERRUPT			0
+#define 	ENDPOINT_A_INTERRUPT			1
+#define 	ENDPOINT_B_INTERRUPT			2
+#define 	ENDPOINT_C_INTERRUPT			3
+#define 	VIRTUALIZED_ENDPOINT_INTERRUPT		4
+#define 	SETUP_PACKET_INTERRUPT			5
+#define 	DMA_DONE_INTERRUPT			6
+#define 	SOF_INTERRUPT				7
+#define IRQSTAT1			0x03
+#define 	CONTROL_STATUS_INTERRUPT		1
+#define 	VBUS_INTERRUPT				2
+#define 	SUSPEND_REQUEST_INTERRUPT		3
+#define 	SUSPEND_REQUEST_CHANGE_INTERRUPT	4
+#define 	RESUME_INTERRUPT			5
+#define 	ROOT_PORT_RESET_INTERRUPT		6
+#define 	RESET_STATUS				7
+#define PAGESEL				0x04
+#define DMAREQ				0x1c
+#define 	DMA_ENDPOINT_SELECT			0
+#define 	DREQ_POLARITY				1
+#define 	DACK_POLARITY				2
+#define 	EOT_POLARITY				3
+#define 	DMA_CONTROL_DACK			4
+#define 	DMA_REQUEST_ENABLE			5
+#define 	DMA_REQUEST				6
+#define 	DMA_BUFFER_VALID			7
+#define SCRATCH				0x1d
+#define IRQENB0				0x20
+#define 	ENDPOINT_0_INTERRUPT_ENABLE		0
+#define 	ENDPOINT_A_INTERRUPT_ENABLE		1
+#define 	ENDPOINT_B_INTERRUPT_ENABLE		2
+#define 	ENDPOINT_C_INTERRUPT_ENABLE		3
+#define 	VIRTUALIZED_ENDPOINT_INTERRUPT_ENABLE	4
+#define 	SETUP_PACKET_INTERRUPT_ENABLE		5
+#define 	DMA_DONE_INTERRUPT_ENABLE		6
+#define 	SOF_INTERRUPT_ENABLE			7
+#define IRQENB1				0x21
+#define 	VBUS_INTERRUPT_ENABLE			2
+#define 	SUSPEND_REQUEST_INTERRUPT_ENABLE	3
+#define 	SUSPEND_REQUEST_CHANGE_INTERRUPT_ENABLE	4
+#define 	RESUME_INTERRUPT_ENABLE			5
+#define 	ROOT_PORT_RESET_INTERRUPT_ENABLE	6
+#define LOCCTL				0x22
+#define 	DATA_WIDTH				0
+#define 	LOCAL_CLOCK_OUTPUT			1
+#define 		LOCAL_CLOCK_OUTPUT_OFF			0
+#define 		LOCAL_CLOCK_OUTPUT_3_75MHZ		1
+#define 		LOCAL_CLOCK_OUTPUT_7_5MHZ		2
+#define 		LOCAL_CLOCK_OUTPUT_15MHZ		3
+#define 		LOCAL_CLOCK_OUTPUT_30MHZ		4
+#define 		LOCAL_CLOCK_OUTPUT_60MHZ		5
+#define 	DMA_SPLIT_BUS_MODE			4
+#define 	BYTE_SWAP				5
+#define 	BUFFER_CONFIGURATION			6
+#define 		BUFFER_CONFIGURATION_EPA512_EPB512	0
+#define 		BUFFER_CONFIGURATION_EPA1024_EPB512	1
+#define 		BUFFER_CONFIGURATION_EPA1024_EPB1024	2
+#define 		BUFFER_CONFIGURATION_EPA1024DB		3
+#define CHIPREV_LEGACY			0x23
+#define 		NET2270_LEGACY_REV			0x40
+#define LOCCTL1				0x24
+#define 	DMA_MODE				0
+#define 		SLOW_DREQ				0
+#define 		FAST_DREQ				1
+#define 		BURST_MODE				2
+#define 	DMA_DACK_ENABLE				2
+#define CHIPREV_2272			0x25
+#define 		CHIPREV_NET2272_R1			0x10
+#define 		CHIPREV_NET2272_R1A			0x11
+/* USB Registers */
+#define USBCTL0				0x18
+#define 	IO_WAKEUP_ENABLE			1
+#define 	USB_DETECT_ENABLE			3
+#define 	USB_ROOT_PORT_WAKEUP_ENABLE		5
+#define USBCTL1				0x19
+#define 	VBUS_PIN				0
+#define 		USB_FULL_SPEED				1
+#define 		USB_HIGH_SPEED				2
+#define 	GENERATE_RESUME				3
+#define 	VIRTUAL_ENDPOINT_ENABLE			4
+#define FRAME0				0x1a
+#define FRAME1				0x1b
+#define OURADDR				0x30
+#define 	FORCE_IMMEDIATE				7
+#define USBDIAG				0x31
+#define 	FORCE_TRANSMIT_CRC_ERROR		0
+#define 	PREVENT_TRANSMIT_BIT_STUFF		1
+#define 	FORCE_RECEIVE_ERROR			2
+#define 	FAST_TIMES				4
+#define USBTEST				0x32
+#define 	TEST_MODE_SELECT			0
+#define 		NORMAL_OPERATION			0
+#define 		TEST_J					1
+#define 		TEST_K					2
+#define 		TEST_SE0_NAK				3
+#define 		TEST_PACKET				4
+#define 		TEST_FORCE_ENABLE			5
+#define XCVRDIAG			0x33
+#define 	FORCE_FULL_SPEED			2
+#define 	FORCE_HIGH_SPEED			3
+#define 	OPMODE					4
+#define 		NORMAL_OPERATION			0
+#define 		NON_DRIVING				1
+#define 		DISABLE_BITSTUFF_AND_NRZI_ENCODE	2
+#define 	LINESTATE				6
+#define 		SE0_STATE				0
+#define 		J_STATE					1
+#define 		K_STATE					2
+#define 		SE1_STATE				3
+#define VIRTOUT0			0x34
+#define VIRTOUT1			0x35
+#define VIRTIN0				0x36
+#define VIRTIN1				0x37
+#define SETUP0				0x40
+#define SETUP1				0x41
+#define SETUP2				0x42
+#define SETUP3				0x43
+#define SETUP4				0x44
+#define SETUP5				0x45
+#define SETUP6				0x46
+#define SETUP7				0x47
+/* Endpoint Registers (Paged via PAGESEL) */
+#define EP_DATA				0x05
+#define EP_STAT0			0x06
+#define 	DATA_IN_TOKEN_INTERRUPT			0
+#define 	DATA_OUT_TOKEN_INTERRUPT		1
+#define 	DATA_PACKET_TRANSMITTED_INTERRUPT	2
+#define 	DATA_PACKET_RECEIVED_INTERRUPT		3
+#define 	SHORT_PACKET_TRANSFERRED_INTERRUPT	4
+#define 	NAK_OUT_PACKETS				5
+#define 	BUFFER_EMPTY				6
+#define 	BUFFER_FULL				7
+#define EP_STAT1			0x07
+#define 	TIMEOUT					0
+#define 	USB_OUT_ACK_SENT			1
+#define 	USB_OUT_NAK_SENT			2
+#define 	USB_IN_ACK_RCVD				3
+#define 	USB_IN_NAK_SENT				4
+#define 	USB_STALL_SENT				5
+#define 	LOCAL_OUT_ZLP				6
+#define 	BUFFER_FLUSH				7
+#define EP_TRANSFER0			0x08
+#define EP_TRANSFER1			0x09
+#define EP_TRANSFER2			0x0a
+#define EP_IRQENB			0x0b
+#define 	DATA_IN_TOKEN_INTERRUPT_ENABLE		0
+#define 	DATA_OUT_TOKEN_INTERRUPT_ENABLE		1
+#define 	DATA_PACKET_TRANSMITTED_INTERRUPT_ENABLE	2
+#define 	DATA_PACKET_RECEIVED_INTERRUPT_ENABLE	3
+#define 	SHORT_PACKET_TRANSFERRED_INTERRUPT_ENABLE	4
+#define EP_AVAIL0			0x0c
+#define EP_AVAIL1			0x0d
+#define EP_RSPCLR			0x0e
+#define EP_RSPSET			0x0f
+#define 	ENDPOINT_HALT				0
+#define 	ENDPOINT_TOGGLE				1
+#define 	NAK_OUT_PACKETS_MODE			2
+#define 	CONTROL_STATUS_PHASE_HANDSHAKE		3
+#define 	INTERRUPT_MODE				4
+#define 	AUTOVALIDATE				5
+#define 	HIDE_STATUS_PHASE			6
+#define 	ALT_NAK_OUT_PACKETS			7
+#define EP_MAXPKT0			0x28
+#define EP_MAXPKT1			0x29
+#define 	ADDITIONAL_TRANSACTION_OPPORTUNITIES	3
+#define 		NONE_ADDITIONAL_TRANSACTION		0
+#define 		ONE_ADDITIONAL_TRANSACTION		1
+#define 		TWO_ADDITIONAL_TRANSACTION		2
+#define EP_CFG				0x2a
+#define 	ENDPOINT_NUMBER				0
+#define 	ENDPOINT_DIRECTION			4
+#define 	ENDPOINT_TYPE				5
+#define 	ENDPOINT_ENABLE				7
+#define EP_HBW				0x2b
+#define 	HIGH_BANDWIDTH_OUT_TRANSACTION_PID	0
+#define 		DATA0_PID				0
+#define 		DATA1_PID				1
+#define 		DATA2_PID				2
+#define 		MDATA_PID				3
+#define EP_BUFF_STATES			0x2c
+#define 	BUFFER_A_STATE				0
+#define 	BUFFER_B_STATE				2
+#define 		BUFF_FREE				0
+#define 		BUFF_VALID				1
+#define 		BUFF_LCL				2
+#define 		BUFF_USB				3
+
+/*---------------------------------------------------------------------------*/
+
+#define PCI_DEVICE_ID_RDK1	0x9054
+
+/* PCI-RDK EPLD Registers */
+#define RDK_EPLD_IO_REGISTER1		0x00000000
+#define 	RDK_EPLD_USB_RESET				0
+#define 	RDK_EPLD_USB_POWERDOWN				1
+#define 	RDK_EPLD_USB_WAKEUP				2
+#define 	RDK_EPLD_USB_EOT				3
+#define 	RDK_EPLD_DPPULL					4
+#define RDK_EPLD_IO_REGISTER2		0x00000004
+#define 	RDK_EPLD_BUSWIDTH				0
+#define 	RDK_EPLD_USER					2
+#define 	RDK_EPLD_RESET_INTERRUPT_ENABLE			3
+#define 	RDK_EPLD_DMA_TIMEOUT_ENABLE			4
+#define RDK_EPLD_STATUS_REGISTER	0x00000008
+#define 	RDK_EPLD_USB_LRESET				0
+#define RDK_EPLD_REVISION_REGISTER	0x0000000c
+
+/* PCI-RDK PLX 9054 Registers */
+#define INTCSR				0x68
+#define 	PCI_INTERRUPT_ENABLE				8
+#define 	LOCAL_INTERRUPT_INPUT_ENABLE			11
+#define 	LOCAL_INPUT_INTERRUPT_ACTIVE			15
+#define 	LOCAL_DMA_CHANNEL_0_INTERRUPT_ENABLE		18
+#define 	LOCAL_DMA_CHANNEL_1_INTERRUPT_ENABLE		19
+#define 	DMA_CHANNEL_0_INTERRUPT_ACTIVE			21
+#define 	DMA_CHANNEL_1_INTERRUPT_ACTIVE			22
+#define CNTRL				0x6C
+#define 	RELOAD_CONFIGURATION_REGISTERS			29
+#define 	PCI_ADAPTER_SOFTWARE_RESET			30
+#define DMAMODE0			0x80
+#define 	LOCAL_BUS_WIDTH					0
+#define 	INTERNAL_WAIT_STATES				2
+#define 	TA_READY_INPUT_ENABLE				6
+#define 	LOCAL_BURST_ENABLE				8
+#define 	SCATTER_GATHER_MODE				9
+#define 	DONE_INTERRUPT_ENABLE				10
+#define 	LOCAL_ADDRESSING_MODE				11
+#define 	DEMAND_MODE					12
+#define 	DMA_EOT_ENABLE					14
+#define 	FAST_SLOW_TERMINATE_MODE_SELECT			15
+#define 	DMA_CHANNEL_INTERRUPT_SELECT			17
+#define DMAPADR0			0x84
+#define DMALADR0			0x88
+#define DMASIZ0				0x8c
+#define DMADPR0				0x90
+#define 	DESCRIPTOR_LOCATION				0
+#define 	END_OF_CHAIN					1
+#define 	INTERRUPT_AFTER_TERMINAL_COUNT			2
+#define 	DIRECTION_OF_TRANSFER				3
+#define DMACSR0				0xa8
+#define 	CHANNEL_ENABLE					0
+#define 	CHANNEL_START					1
+#define 	CHANNEL_ABORT					2
+#define 	CHANNEL_CLEAR_INTERRUPT				3
+#define 	CHANNEL_DONE					4
+#define DMATHR				0xb0
+#define LBRD1				0xf8
+#define 	MEMORY_SPACE_LOCAL_BUS_WIDTH			0
+#define 	W8_BIT						0
+#define 	W16_BIT						1
+
+/* Special OR'ing of INTCSR bits */
+#define LOCAL_INTERRUPT_TEST \
+	((1 << LOCAL_INPUT_INTERRUPT_ACTIVE) | \
+	 (1 << LOCAL_INTERRUPT_INPUT_ENABLE))
+
+#define DMA_CHANNEL_0_TEST \
+	((1 << DMA_CHANNEL_0_INTERRUPT_ACTIVE) | \
+	 (1 << LOCAL_DMA_CHANNEL_0_INTERRUPT_ENABLE))
+
+#define DMA_CHANNEL_1_TEST \
+	((1 << DMA_CHANNEL_1_INTERRUPT_ACTIVE) | \
+	 (1 << LOCAL_DMA_CHANNEL_1_INTERRUPT_ENABLE))
+
+/* EPLD Registers */
+#define RDK_EPLD_IO_REGISTER1			0x00000000
+#define 	RDK_EPLD_USB_RESET			0
+#define 	RDK_EPLD_USB_POWERDOWN			1
+#define 	RDK_EPLD_USB_WAKEUP			2
+#define 	RDK_EPLD_USB_EOT			3
+#define 	RDK_EPLD_DPPULL				4
+#define RDK_EPLD_IO_REGISTER2			0x00000004
+#define 	RDK_EPLD_BUSWIDTH			0
+#define 	RDK_EPLD_USER				2
+#define 	RDK_EPLD_RESET_INTERRUPT_ENABLE		3
+#define 	RDK_EPLD_DMA_TIMEOUT_ENABLE		4
+#define RDK_EPLD_STATUS_REGISTER		0x00000008
+#define RDK_EPLD_USB_LRESET				0
+#define RDK_EPLD_REVISION_REGISTER		0x0000000c
+
+#define EPLD_IO_CONTROL_REGISTER		0x400
+#define 	NET2272_RESET				0
+#define 	BUSWIDTH				1
+#define 	MPX_MODE				3
+#define 	USER					4
+#define 	DMA_TIMEOUT_ENABLE			5
+#define 	DMA_CTL_DACK				6
+#define 	EPLD_DMA_ENABLE				7
+#define EPLD_DMA_CONTROL_REGISTER		0x800
+#define 	SPLIT_DMA_MODE				0
+#define 	SPLIT_DMA_DIRECTION			1
+#define 	SPLIT_DMA_ENABLE			2
+#define 	SPLIT_DMA_INTERRUPT_ENABLE		3
+#define 	SPLIT_DMA_INTERRUPT			4
+#define 	EPLD_DMA_MODE				5
+#define 	EPLD_DMA_CONTROLLER_ENABLE		7
+#define SPLIT_DMA_ADDRESS_LOW			0xc00
+#define SPLIT_DMA_ADDRESS_HIGH			0x1000
+#define SPLIT_DMA_BYTE_COUNT_LOW		0x1400
+#define SPLIT_DMA_BYTE_COUNT_HIGH		0x1800
+#define EPLD_REVISION_REGISTER			0x1c00
+#define SPLIT_DMA_RAM				0x4000
+#define DMA_RAM_SIZE				0x1000
+
+/*---------------------------------------------------------------------------*/
+
+#define PCI_DEVICE_ID_RDK2	0x3272
+
+/* PCI-RDK version 2 registers */
+
+/* Main Control Registers */
+
+#define RDK2_IRQENB			0x00
+#define RDK2_IRQSTAT			0x04
+#define 	PB7				23
+#define 	PB6				22
+#define 	PB5				21
+#define 	PB4				20
+#define 	PB3				19
+#define 	PB2				18
+#define 	PB1				17
+#define 	PB0				16
+#define 	GP3				23
+#define 	GP2				23
+#define 	GP1				23
+#define 	GP0				23
+#define 	DMA_RETRY_ABORT			6
+#define 	DMA_PAUSE_DONE			5
+#define 	DMA_ABORT_DONE			4
+#define 	DMA_OUT_FIFO_TRANSFER_DONE	3
+#define 	DMA_LOCAL_DONE			2
+#define 	DMA_PCI_DONE			1
+#define 	NET2272_PCI_IRQ			0
+
+#define RDK2_LOCCTLRDK			0x08
+#define 	CHIP_RESET			3
+#define 	SPLIT_DMA			2
+#define 	MULTIPLEX_MODE			1
+#define 	BUS_WIDTH			0
+
+#define RDK2_GPIOCTL			0x10
+#define 	GP3_OUT_ENABLE					7
+#define 	GP2_OUT_ENABLE					6
+#define 	GP1_OUT_ENABLE					5
+#define 	GP0_OUT_ENABLE					4
+#define 	GP3_DATA					3
+#define 	GP2_DATA					2
+#define 	GP1_DATA					1
+#define 	GP0_DATA					0
+
+#define RDK2_LEDSW			0x14
+#define 	LED3				27
+#define 	LED2				26
+#define 	LED1				25
+#define 	LED0				24
+#define 	PBUTTON				16
+#define 	DIPSW				0
+
+#define RDK2_DIAG			0x18
+#define 	RDK2_FAST_TIMES				2
+#define 	FORCE_PCI_SERR				1
+#define 	FORCE_PCI_INT				0
+#define RDK2_FPGAREV			0x1C
+
+/* Dma Control registers */
+#define RDK2_DMACTL			0x80
+#define 	ADDR_HOLD				24
+#define 	RETRY_COUNT				16	/* 23:16 */
+#define 	FIFO_THRESHOLD				11	/* 15:11 */
+#define 	MEM_WRITE_INVALIDATE			10
+#define 	READ_MULTIPLE				9
+#define 	READ_LINE				8
+#define 	RDK2_DMA_MODE				6	/* 7:6 */
+#define 	CONTROL_DACK				5
+#define 	EOT_ENABLE				4
+#define 	EOT_POLARITY				3
+#define 	DACK_POLARITY				2
+#define 	DREQ_POLARITY				1
+#define 	DMA_ENABLE				0
+
+#define RDK2_DMASTAT			0x84
+#define 	GATHER_COUNT				12	/* 14:12 */
+#define 	FIFO_COUNT				6	/* 11:6 */
+#define 	FIFO_FLUSH				5
+#define 	FIFO_TRANSFER				4
+#define 	PAUSE_DONE				3
+#define 	ABORT_DONE				2
+#define 	DMA_ABORT				1
+#define 	DMA_START				0
+
+#define RDK2_DMAPCICOUNT		0x88
+#define 	DMA_DIRECTION				31
+#define 	DMA_PCI_BYTE_COUNT			0	/* 0:23 */
+
+#define RDK2_DMALOCCOUNT		0x8C	/* 0:23 dma local byte count */
+
+#define RDK2_DMAADDR			0x90	/* 2:31 PCI bus starting address */
+
+/*---------------------------------------------------------------------------*/
+
+#define REG_INDEXED_THRESHOLD	(1 << 5)
+
+/* DRIVER DATA STRUCTURES and UTILITIES */
+struct net2272_ep {
+	struct usb_ep ep;
+	struct net2272 *dev;
+	unsigned long irqs;
+
+	/* analogous to a host-side qh */
+	struct list_head queue;
+	const struct usb_endpoint_descriptor *desc;
+	unsigned num:8,
+	         fifo_size:12,
+	         stopped:1,
+	         wedged:1,
+	         is_in:1,
+	         is_iso:1,
+	         dma:1,
+	         not_empty:1;
+};
+
+struct net2272 {
+	/* each device provides one gadget, several endpoints */
+	struct usb_gadget gadget;
+	struct device *dev;
+	unsigned short dev_id;
+
+	spinlock_t lock;
+	struct net2272_ep ep[4];
+	struct usb_gadget_driver *driver;
+	unsigned protocol_stall:1,
+	         softconnect:1,
+	         is_selfpowered:1,
+	         wakeup:1,
+	         dma_eot_polarity:1,
+	         dma_dack_polarity:1,
+	         dma_dreq_polarity:1,
+	         dma_busy:1;
+	u16 chiprev;
+	u8 pagesel;
+
+	unsigned int irq;
+	unsigned short fifo_mode;
+
+	unsigned int base_shift;
+	u16 __iomem *base_addr;
+	union {
+#ifdef CONFIG_PCI
+		struct {
+			void __iomem *plx9054_base_addr;
+			void __iomem *epld_base_addr;
+		} rdk1;
+		struct {
+			/* Bar0, Bar1 is base_addr both mem-mapped */
+			void __iomem *fpga_base_addr;
+		} rdk2;
+#endif
+	};
+};
+
+static void __iomem *
+net2272_reg_addr(struct net2272 *dev, unsigned int reg)
+{
+	return dev->base_addr + (reg << dev->base_shift);
+}
+
+static void
+net2272_write(struct net2272 *dev, unsigned int reg, u8 value)
+{
+	if (reg >= REG_INDEXED_THRESHOLD) {
+		/*
+		 * Indexed register; use REGADDRPTR/REGDATA
+		 *  - Save and restore REGADDRPTR. This prevents REGADDRPTR from
+		 *    changes between other code sections, but it is time consuming.
+		 *  - Performance tips: either do not save and restore REGADDRPTR (if it
+		 *    is safe) or do save/restore operations only in critical sections.
+		u8 tmp = readb(dev->base_addr + REGADDRPTR);
+		 */
+		writeb((u8)reg, net2272_reg_addr(dev, REGADDRPTR));
+		writeb(value, net2272_reg_addr(dev, REGDATA));
+		/* writeb(tmp, net2272_reg_addr(dev, REGADDRPTR)); */
+	} else
+		writeb(value, net2272_reg_addr(dev, reg));
+}
+
+static u8
+net2272_read(struct net2272 *dev, unsigned int reg)
+{
+	u8 ret;
+
+	if (reg >= REG_INDEXED_THRESHOLD) {
+		/*
+		 * Indexed register; use REGADDRPTR/REGDATA
+		 *  - Save and restore REGADDRPTR. This prevents REGADDRPTR from
+		 *    changes between other code sections, but it is time consuming.
+		 *  - Performance tips: either do not save and restore REGADDRPTR (if it
+		 *    is safe) or do save/restore operations only in critical sections.
+		u8 tmp = readb(dev->base_addr + REGADDRPTR);
+		 */
+		writeb((u8)reg, net2272_reg_addr(dev, REGADDRPTR));
+		ret = readb(net2272_reg_addr(dev, REGDATA));
+		/* writeb(tmp, net2272_reg_addr(dev, REGADDRPTR)); */
+	} else
+		ret = readb(net2272_reg_addr(dev, reg));
+
+	return ret;
+}
+
+static void
+net2272_ep_write(struct net2272_ep *ep, unsigned int reg, u8 value)
+{
+	struct net2272 *dev = ep->dev;
+
+	if (dev->pagesel != ep->num) {
+		net2272_write(dev, PAGESEL, ep->num);
+		dev->pagesel = ep->num;
+	}
+	net2272_write(dev, reg, value);
+}
+
+static u8
+net2272_ep_read(struct net2272_ep *ep, unsigned int reg)
+{
+	struct net2272 *dev = ep->dev;
+
+	if (dev->pagesel != ep->num) {
+		net2272_write(dev, PAGESEL, ep->num);
+		dev->pagesel = ep->num;
+	}
+	return net2272_read(dev, reg);
+}
+
+static void allow_status(struct net2272_ep *ep)
+{
+	/* ep0 only */
+	net2272_ep_write(ep, EP_RSPCLR,
+		(1 << CONTROL_STATUS_PHASE_HANDSHAKE) |
+		(1 << ALT_NAK_OUT_PACKETS) |
+		(1 << NAK_OUT_PACKETS_MODE));
+	ep->stopped = 1;
+}
+
+static void set_halt(struct net2272_ep *ep)
+{
+	/* ep0 and bulk/intr endpoints */
+	net2272_ep_write(ep, EP_RSPCLR, 1 << CONTROL_STATUS_PHASE_HANDSHAKE);
+	net2272_ep_write(ep, EP_RSPSET, 1 << ENDPOINT_HALT);
+}
+
+static void clear_halt(struct net2272_ep *ep)
+{
+	/* ep0 and bulk/intr endpoints */
+	net2272_ep_write(ep, EP_RSPCLR,
+		(1 << ENDPOINT_HALT) | (1 << ENDPOINT_TOGGLE));
+}
+
+/* count (<= 4) bytes in the next fifo write will be valid */
+static void set_fifo_bytecount(struct net2272_ep *ep, unsigned count)
+{
+	/* net2272_ep_write will truncate to u8 for us */
+	net2272_ep_write(ep, EP_TRANSFER2, count >> 16);
+	net2272_ep_write(ep, EP_TRANSFER1, count >> 8);
+	net2272_ep_write(ep, EP_TRANSFER0, count);
+}
+
+struct net2272_request {
+	struct usb_request req;
+	struct list_head queue;
+	unsigned mapped:1,
+	         valid:1;
+};
+
+#endif