sh: Add maple bus support for the SEGA Dreamcast.

The Maple bus is SEGA's proprietary serial bus for peripherals
(keyboard, mouse, controller etc). The bus is capable of some
(limited) hotplugging and operates at up to 2 M/bits.

Drivers of one sort or another existed/exist for 2.4 and a rudimentary
port, which didn't support the 2.6 device driver model was also in
existence.

This driver - for the bus logic itself and for the keyboard (other
drivers will follow) are based on the code and concepts of those old
drivers but have lots of completely rewritten parts.

I have the maple bus code as a built in now as that seems the sane and
rational way to handle something like that - you either want the bus
or you don't.
Signed-off-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/Kconfig

@@ -666,6 +666,17 @@ config SUPERHYWAY
 	tristate "SuperHyway Bus support"
 	depends on CPU_SUBTYPE_SH4_202
 
+config MAPLE
+       bool "Maple Bus support"
+       depends on SH_DREAMCAST
+       help
+         The Maple Bus is SEGA's serial communication bus for peripherals
+         on the Dreamcast. Without this bus support you won't be able to
+         get your Dreamcast keyboard etc to work, so most users
+         probably want to say 'Y' here, unless you are only using the
+         Dreamcast with a serial line terminal or a remote network
+         connection.
+
 config CF_ENABLER
 	bool "Compact Flash Enabler support"
 	depends on SOLUTION_ENGINE || SH_SH03

drivers/sh/Makefile

@@ -3,4 +3,4 @@
 #
 
 obj-$(CONFIG_SUPERHYWAY)	+= superhyway/
-
+obj-$(CONFIG_MAPLE)		+= maple/

drivers/sh/maple/Makefile

+# Makefile for Maple Bus
+
+obj-$(CONFIG_MAPLE) := maple.o

include/asm-sh/dreamcast/maple.h

+#ifndef __ASM_MAPLE_H
+#define __ASM_MAPLE_H
+
+#define MAPLE_PORTS 4
+#define MAPLE_PNP_INTERVAL HZ
+#define MAPLE_MAXPACKETS 8
+#define MAPLE_DMA_ORDER 14
+#define MAPLE_DMA_SIZE (1 << MAPLE_DMA_ORDER)
+#define MAPLE_DMA_PAGES ((MAPLE_DMA_ORDER > PAGE_SHIFT) ? \
+			  MAPLE_DMA_ORDER - PAGE_SHIFT : 0)
+
+/* Maple Bus registers */
+#define MAPLE_BASE     0xa05f6c00
+#define MAPLE_DMAADDR  (MAPLE_BASE+0x04)
+#define MAPLE_TRIGTYPE (MAPLE_BASE+0x10)
+#define MAPLE_ENABLE   (MAPLE_BASE+0x14)
+#define MAPLE_STATE    (MAPLE_BASE+0x18)
+#define MAPLE_SPEED    (MAPLE_BASE+0x80)
+#define MAPLE_RESET    (MAPLE_BASE+0x8c)
+
+#define MAPLE_MAGIC    0x6155404f
+#define MAPLE_2MBPS    0
+#define MAPLE_TIMEOUT(n) ((n)<<15)
+
+/* Function codes */
+#define MAPLE_FUNC_CONTROLLER 0x001
+#define MAPLE_FUNC_MEMCARD    0x002
+#define MAPLE_FUNC_LCD        0x004
+#define MAPLE_FUNC_CLOCK      0x008
+#define MAPLE_FUNC_MICROPHONE 0x010
+#define MAPLE_FUNC_ARGUN      0x020
+#define MAPLE_FUNC_KEYBOARD   0x040
+#define MAPLE_FUNC_LIGHTGUN   0x080
+#define MAPLE_FUNC_PURUPURU   0x100
+#define MAPLE_FUNC_MOUSE      0x200
+
+#endif /* __ASM_MAPLE_H */

include/linux/maple.h

+#ifndef __LINUX_MAPLE_H
+#define __LINUX_MAPLE_H
+
+#include <linux/device.h>
+
+extern struct bus_type maple_bus_type;
+
+/* Maple Bus command and response codes */
+enum maple_code {
+       MAPLE_RESPONSE_FILEERR = -5,
+       MAPLE_RESPONSE_AGAIN = -4,      /* request should be retransmitted */
+       MAPLE_RESPONSE_BADCMD = -3,
+       MAPLE_RESPONSE_BADFUNC = -2,
+       MAPLE_RESPONSE_NONE = -1,       /* unit didn't respond at all */
+       MAPLE_COMMAND_DEVINFO = 1,
+       MAPLE_COMMAND_ALLINFO = 2,
+       MAPLE_COMMAND_RESET = 3,
+       MAPLE_COMMAND_KILL = 4,
+       MAPLE_RESPONSE_DEVINFO = 5,
+       MAPLE_RESPONSE_ALLINFO = 6,
+       MAPLE_RESPONSE_OK = 7,
+       MAPLE_RESPONSE_DATATRF = 8,
+       MAPLE_COMMAND_GETCOND = 9,
+       MAPLE_COMMAND_GETMINFO = 10,
+       MAPLE_COMMAND_BREAD = 11,
+       MAPLE_COMMAND_BWRITE = 12,
+       MAPLE_COMMAND_SETCOND = 14
+};
+
+struct mapleq {
+       struct list_head list;
+       struct maple_device *dev;
+       void *sendbuf, *recvbuf, *recvbufdcsp;
+       unsigned char length;
+       enum maple_code command;
+};
+
+struct maple_devinfo {
+       unsigned long function;
+       unsigned long function_data[3];
+       unsigned char area_code;
+       unsigned char connector_directon;
+       char product_name[31];
+       char product_licence[61];
+       unsigned short standby_power;
+       unsigned short max_power;
+};
+
+struct maple_device {
+       struct maple_driver *driver;
+       struct mapleq *mq;
+       void *private_data;
+       void (*callback) (struct mapleq * mq);
+       unsigned long when, interval, function;
+       struct maple_devinfo devinfo;
+       unsigned char port, unit;
+       char product_name[32];
+       char product_licence[64];
+       int registered;
+       struct device dev;
+};
+
+struct maple_driver {
+       unsigned long function;
+       int (*connect) (struct maple_device * dev);
+       void (*disconnect) (struct maple_device * dev);
+       struct device_driver drv;
+};
+
+void maple_getcond_callback(struct maple_device *dev,
+                           void (*callback) (struct mapleq * mq),
+                           unsigned long interval,
+                           unsigned long function);
+int maple_driver_register(struct device_driver *drv);
+void maple_add_packet(struct mapleq *mq);
+
+#define to_maple_dev(n) container_of(n, struct maple_device, dev)
+#define to_maple_driver(n) container_of(n, struct maple_driver, drv)
+
+#endif /* __LINUX_MAPLE_H */