[PATCH] I2C: Add PXA I2C driver

Add support for the I2C PXA driver.

Signed-off-by: Russell King <rmk@arm.linux.org.uk>

drivers/i2c/busses/Kconfig

@@ -144,6 +144,22 @@ config I2C_I810
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-i810.
 
+config I2C_PXA
+	tristate "Intel PXA2XX I2C adapter (EXPERIMENTAL)"
+	depends on I2C && EXPERIMENTAL && ARCH_PXA
+	help
+	  If you have devices in the PXA I2C bus, say yes to this option.
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-pxa.
+
+config I2C_PXA_SLAVE
+	bool "Intel PXA2XX I2C Slave comms support"
+	depends on I2C_PXA
+	help
+	  Support I2C slave mode communications on the PXA I2C bus.  This
+	  is necessary for systems where the PXA may be a target on the
+	  I2C bus.
+
 config I2C_PIIX4
 	tristate "Intel PIIX4"
 	depends on I2C && PCI

drivers/i2c/busses/Makefile

@@ -28,6 +28,7 @@ obj-$(CONFIG_I2C_PARPORT_LIGHT)	+= i2c-parport-light.o
 obj-$(CONFIG_I2C_PCA_ISA)	+= i2c-pca-isa.o
 obj-$(CONFIG_I2C_PIIX4)		+= i2c-piix4.o
 obj-$(CONFIG_I2C_PROSAVAGE)	+= i2c-prosavage.o
+obj-$(CONFIG_I2C_PXA)		+= i2c-pxa.o
 obj-$(CONFIG_I2C_RPXLITE)	+= i2c-rpx.o
 obj-$(CONFIG_I2C_S3C2410)	+= i2c-s3c2410.o
 obj-$(CONFIG_I2C_SAVAGE4)	+= i2c-savage4.o

include/asm-arm/arch-pxa/i2c.h

@@ -0,0 +1,70 @@
+/*
+ *  i2c_pxa.h
+ *
+ *  Copyright (C) 2002 Intrinsyc Software Inc.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ *
+ */
+#ifndef _I2C_PXA_H_
+#define _I2C_PXA_H_
+
+#if 0
+#define DEF_TIMEOUT             3
+#else
+/* need a longer timeout if we're dealing with the fact we may well be
+ * looking at a multi-master environment
+*/
+#define DEF_TIMEOUT             32
+#endif
+
+#define BUS_ERROR               (-EREMOTEIO)
+#define XFER_NAKED              (-ECONNREFUSED)
+#define I2C_RETRY               (-2000) /* an error has occurred retry transmit */
+
+/* ICR initialize bit values
+*
+*  15. FM       0 (100 Khz operation)
+*  14. UR       0 (No unit reset)
+*  13. SADIE    0 (Disables the unit from interrupting on slave addresses
+*                                       matching its slave address)
+*  12. ALDIE    0 (Disables the unit from interrupt when it loses arbitration
+*                                       in master mode)
+*  11. SSDIE    0 (Disables interrupts from a slave stop detected, in slave mode)
+*  10. BEIE     1 (Enable interrupts from detected bus errors, no ACK sent)
+*  9.  IRFIE    1 (Enable interrupts from full buffer received)
+*  8.  ITEIE    1 (Enables the I2C unit to interrupt when transmit buffer empty)
+*  7.  GCD      1 (Disables i2c unit response to general call messages as a slave)
+*  6.  IUE      0 (Disable unit until we change settings)
+*  5.  SCLE     1 (Enables the i2c clock output for master mode (drives SCL)
+*  4.  MA       0 (Only send stop with the ICR stop bit)
+*  3.  TB       0 (We are not transmitting a byte initially)
+*  2.  ACKNAK   0 (Send an ACK after the unit receives a byte)
+*  1.  STOP     0 (Do not send a STOP)
+*  0.  START    0 (Do not send a START)
+*
+*/
+#define I2C_ICR_INIT	(ICR_BEIE | ICR_IRFIE | ICR_ITEIE | ICR_GCD | ICR_SCLE)
+
+/* I2C status register init values
+ *
+ * 10. BED      1 (Clear bus error detected)
+ * 9.  SAD      1 (Clear slave address detected)
+ * 7.  IRF      1 (Clear IDBR Receive Full)
+ * 6.  ITE      1 (Clear IDBR Transmit Empty)
+ * 5.  ALD      1 (Clear Arbitration Loss Detected)
+ * 4.  SSD      1 (Clear Slave Stop Detected)
+ */
+#define I2C_ISR_INIT	0x7FF  /* status register init */
+
+struct i2c_slave_client;
+
+struct i2c_pxa_platform_data {
+	unsigned int		slave_addr;
+	struct i2c_slave_client	*slave;
+};
+
+extern void pxa_set_i2c_info(struct i2c_pxa_platform_data *info);
+#endif

include/linux/i2c-id.h

@@ -203,6 +203,7 @@
 #define I2C_ALGO_MV64XXX 0x190000	/* Marvell mv64xxx i2c ctlr	*/
 #define I2C_ALGO_PCA	0x1a0000	/* PCA 9564 style adapters	*/
 #define I2C_ALGO_AU1550	0x1b0000        /* Au1550 PSC algorithm		*/
+#define I2C_ALGO_PXA	0x1c0000	/* Intel PXA I2C algorithm	*/
 
 #define I2C_ALGO_EXP	0x800000	/* experimental			*/
 

include/linux/i2c-pxa.h

@@ -0,0 +1,48 @@
+#ifndef _LINUX_I2C_ALGO_PXA_H
+#define _LINUX_I2C_ALGO_PXA_H
+
+struct i2c_eeprom_emu_watcher {
+	void (*write)(void *, unsigned int addr, unsigned char newval);
+};
+
+struct i2c_eeprom_emu_watch {
+	struct list_head node;
+	unsigned int start;
+	unsigned int end;
+	struct i2c_eeprom_emu_watcher *ops;
+	void *data;
+};
+
+#define I2C_EEPROM_EMU_SIZE (256)
+
+struct i2c_eeprom_emu {
+	unsigned int size;
+	unsigned int ptr;
+	unsigned int seen_start;
+	struct list_head watch;
+
+	unsigned char bytes[I2C_EEPROM_EMU_SIZE];
+};
+
+typedef enum i2c_slave_event_e {
+	I2C_SLAVE_EVENT_START_READ,
+	I2C_SLAVE_EVENT_START_WRITE,
+	I2C_SLAVE_EVENT_STOP
+} i2c_slave_event_t;
+
+struct i2c_slave_client {
+	void *data;
+	void (*event)(void *ptr, i2c_slave_event_t event);
+	int  (*read) (void *ptr);
+	void (*write)(void *ptr, unsigned int val);
+};
+
+extern int i2c_eeprom_emu_addwatcher(struct i2c_eeprom_emu *, void *data,
+				     unsigned int addr, unsigned int size,
+				     struct i2c_eeprom_emu_watcher *);
+
+extern void i2c_eeprom_emu_delwatcher(struct i2c_eeprom_emu *, void *data, struct i2c_eeprom_emu_watcher *watcher);
+
+extern struct i2c_eeprom_emu *i2c_pxa_get_eeprom(void);
+
+#endif /* _LINUX_I2C_ALGO_PXA_H */