[PATCH] USB: add support for AT91 gadget

This adds support for the USB peripheral controller on AT91
(rm9200, eventually also sam9261 or uClinux) platforms.

More SOC support for Linux-USB ... an uncomplicated pure PIO driver.
It'd be worth using this as a model, if you're starting a driver
for some other peripheral controller.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/gadget/Kconfig

@@ -187,6 +187,23 @@ config USB_OTG
 
 	   Select this only if your OMAP board has a Mini-AB connector.
 
+config USB_GADGET_AT91
+	boolean "AT91 USB Device Port"
+	depends on ARCH_AT91RM9200
+	select USB_GADGET_SELECTED
+	help
+	   Many Atmel AT91 processors (such as the AT91RM2000) have a
+	   full speed USB Device Port with support for five configurable
+	   endpoints (plus endpoint zero).
+
+	   Say "y" to link the driver statically, or "m" to build a
+	   dynamically linked module called "at91_udc" and force all
+	   gadget drivers to also be dynamically linked.
+
+config USB_AT91
+	tristate
+	depends on USB_GADGET_AT91
+	default USB_GADGET
 
 config USB_GADGET_DUMMY_HCD
 	boolean "Dummy HCD (DEVELOPMENT)"

drivers/usb/gadget/Makefile

@@ -7,6 +7,7 @@ obj-$(CONFIG_USB_PXA2XX)	+= pxa2xx_udc.o
 obj-$(CONFIG_USB_GOKU)		+= goku_udc.o
 obj-$(CONFIG_USB_OMAP)		+= omap_udc.o
 obj-$(CONFIG_USB_LH7A40X)	+= lh7a40x_udc.o
+obj-$(CONFIG_USB_AT91)		+= at91_udc.o
 
 #
 # USB gadget drivers

drivers/usb/gadget/at91_udc.h

@@ -0,0 +1,181 @@
+/*
+ * Copyright (C) 2004 by Thomas Rathbone, HP Labs
+ * Copyright (C) 2005 by Ivan Kokshaysky
+ * Copyright (C) 2006 by SAN People
+ *
+ * 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 AT91_UDC_H
+#define AT91_UDC_H
+
+/*
+ * USB Device Port (UDP) registers.
+ * Based on AT91RM9200 datasheet revision E.
+ */
+
+#define AT91_UDP_FRM_NUM	0x00		/* Frame Number Register */
+#define     AT91_UDP_NUM	(0x7ff <<  0)	/* Frame Number */
+#define     AT91_UDP_FRM_ERR	(1     << 16)	/* Frame Error */
+#define     AT91_UDP_FRM_OK	(1     << 17)	/* Frame OK */
+
+#define AT91_UDP_GLB_STAT	0x04		/* Global State Register */
+#define     AT91_UDP_FADDEN	(1 <<  0)	/* Function Address Enable */
+#define     AT91_UDP_CONFG	(1 <<  1)	/* Configured */
+#define     AT91_UDP_ESR	(1 <<  2)	/* Enable Send Resume */
+#define     AT91_UDP_RSMINPR	(1 <<  3)	/* Resume has been sent */
+#define     AT91_UDP_RMWUPE	(1 <<  4)	/* Remote Wake Up Enable */
+
+#define AT91_UDP_FADDR		0x08		/* Function Address Register */
+#define     AT91_UDP_FADD	(0x7f << 0)	/* Function Address Value */
+#define     AT91_UDP_FEN	(1    << 8)	/* Function Enable */
+
+#define AT91_UDP_IER		0x10		/* Interrupt Enable Register */
+#define AT91_UDP_IDR		0x14		/* Interrupt Disable Register */
+#define AT91_UDP_IMR		0x18		/* Interrupt Mask Register */
+
+#define AT91_UDP_ISR		0x1c		/* Interrupt Status Register */
+#define     AT91_UDP_EP(n)	(1 << (n))	/* Endpoint Interrupt Status */
+#define     AT91_UDP_RXSUSP	(1 <<  8) 	/* USB Suspend Interrupt Status */
+#define     AT91_UDP_RXRSM	(1 <<  9)	/* USB Resume Interrupt Status */
+#define     AT91_UDP_EXTRSM	(1 << 10)	/* External Resume Interrupt Status */
+#define     AT91_UDP_SOFINT	(1 << 11)	/* Start of Frame Interrupt Status */
+#define     AT91_UDP_ENDBUSRES	(1 << 12)	/* End of Bus Reset Interrpt Status */
+#define     AT91_UDP_WAKEUP	(1 << 13)	/* USB Wakeup Interrupt Status */
+
+#define AT91_UDP_ICR		0x20		/* Interrupt Clear Register */
+#define AT91_UDP_RST_EP		0x28		/* Reset Endpoint Register */
+
+#define AT91_UDP_CSR(n)		(0x30+((n)*4))	/* Endpoint Control/Status Registers 0-7 */
+#define     AT91_UDP_TXCOMP	(1 <<  0)	/* Generates IN packet with data previously written in DPR */
+#define     AT91_UDP_RX_DATA_BK0 (1 <<  1)	/* Receive Data Bank 0 */
+#define     AT91_UDP_RXSETUP	(1 <<  2)	/* Send STALL to the host */
+#define     AT91_UDP_STALLSENT	(1 <<  3)	/* Stall Sent / Isochronous error (Isochronous endpoints) */
+#define     AT91_UDP_TXPKTRDY	(1 <<  4)	/* Transmit Packet Ready */
+#define     AT91_UDP_FORCESTALL	(1 <<  5)	/* Force Stall */
+#define     AT91_UDP_RX_DATA_BK1 (1 <<  6)	/* Receive Data Bank 1 */
+#define     AT91_UDP_DIR	(1 <<  7)	/* Transfer Direction */
+#define     AT91_UDP_EPTYPE	(7 <<  8)	/* Endpoint Type */
+#define		AT91_UDP_EPTYPE_CTRL		(0 <<  8)
+#define		AT91_UDP_EPTYPE_ISO_OUT		(1 <<  8)
+#define		AT91_UDP_EPTYPE_BULK_OUT	(2 <<  8)
+#define		AT91_UDP_EPTYPE_INT_OUT		(3 <<  8)
+#define		AT91_UDP_EPTYPE_ISO_IN		(5 <<  8)
+#define		AT91_UDP_EPTYPE_BULK_IN		(6 <<  8)
+#define		AT91_UDP_EPTYPE_INT_IN		(7 <<  8)
+#define     AT91_UDP_DTGLE	(1 << 11)	/* Data Toggle */
+#define     AT91_UDP_EPEDS	(1 << 15)	/* Endpoint Enable/Disable */
+#define     AT91_UDP_RXBYTECNT	(0x7ff << 16)	/* Number of bytes in FIFO */
+
+#define AT91_UDP_FDR(n)		(0x50+((n)*4))	/* Endpoint FIFO Data Registers 0-7 */
+
+#define AT91_UDP_TXVC		0x74		/* Transceiver Control Register */
+#define     AT91_UDP_TXVC_TXVDIS (1 << 8)	/* Transceiver Disable */
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * controller driver data structures
+ */
+
+#define	NUM_ENDPOINTS	6
+
+/*
+ * hardware won't disable bus reset, or resume while the controller
+ * is suspended ... watching suspend helps keep the logic symmetric.
+ */
+#define	MINIMUS_INTERRUPTUS \
+	(AT91_UDP_ENDBUSRES | AT91_UDP_RXRSM | AT91_UDP_RXSUSP)
+
+struct at91_ep {
+	struct usb_ep			ep;
+	struct list_head		queue;
+	struct at91_udc			*udc;
+	void __iomem			*creg;
+
+	unsigned			maxpacket:16;
+	u8				int_mask;
+	unsigned			is_pingpong:1;
+
+	unsigned			stopped:1;
+	unsigned			is_in:1;
+	unsigned			is_iso:1;
+	unsigned			fifo_bank:1;
+
+	const struct usb_endpoint_descriptor
+					*desc;
+};
+
+/*
+ * driver is non-SMP, and just blocks IRQs whenever it needs
+ * access protection for chip registers or driver state
+ */
+struct at91_udc {
+	struct usb_gadget		gadget;
+	struct at91_ep			ep[NUM_ENDPOINTS];
+	struct usb_gadget_driver	*driver;
+	unsigned			vbus:1;
+	unsigned			enabled:1;
+	unsigned			clocked:1;
+	unsigned			suspended:1;
+	unsigned			req_pending:1;
+	unsigned			wait_for_addr_ack:1;
+	unsigned			wait_for_config_ack:1;
+	unsigned			selfpowered:1;
+	u8				addr;
+	struct at91_udc_data		board;
+	struct clk			*iclk, *fclk;
+	struct platform_device		*pdev;
+	struct proc_dir_entry		*pde;
+};
+
+static inline struct at91_udc *to_udc(struct usb_gadget *g)
+{
+	return container_of(g, struct at91_udc, gadget);
+}
+
+struct at91_request {
+	struct usb_request		req;
+	struct list_head		queue;
+};
+
+/*-------------------------------------------------------------------------*/
+
+#ifdef DEBUG
+#define DBG(stuff...)		printk(KERN_DEBUG "udc: " stuff)
+#else
+#define DBG(stuff...)		do{}while(0)
+#endif
+
+#ifdef VERBOSE
+#    define VDBG		DBG
+#else
+#    define VDBG(stuff...)	do{}while(0)
+#endif
+
+#ifdef PACKET_TRACE
+#    define PACKET		VDBG
+#else
+#    define PACKET(stuff...)	do{}while(0)
+#endif
+
+#define ERR(stuff...)		printk(KERN_ERR "udc: " stuff)
+#define WARN(stuff...)		printk(KERN_WARNING "udc: " stuff)
+#define INFO(stuff...)		printk(KERN_INFO "udc: " stuff)
+
+#endif
+