[ARM] Acorn: move the i2c bus driver into drivers/i2c
Move the Acorn IOC/IOMD I2C bus driver from drivers/i2c, strip
out the reminants of the platform specific parts of the old
PCF8583 RTC code, and remove the old obsolete PCF8583 driver.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/i2c/busses/i2c-acorn.c b/drivers/i2c/busses/i2c-acorn.c
new file mode 100644
index 0000000..09bd7f4
--- /dev/null
+++ b/drivers/i2c/busses/i2c-acorn.c
@@ -0,0 +1,97 @@
+/*
+ * linux/drivers/acorn/char/i2c.c
+ *
+ * Copyright (C) 2000 Russell King
+ *
+ * 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.
+ *
+ * ARM IOC/IOMD i2c driver.
+ *
+ * On Acorn machines, the following i2c devices are on the bus:
+ * - PCF8583 real time clock & static RAM
+ */
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/hardware/ioc.h>
+#include <asm/system.h>
+
+#define FORCE_ONES 0xdc
+#define SCL 0x02
+#define SDA 0x01
+
+/*
+ * We must preserve all non-i2c output bits in IOC_CONTROL.
+ * Note also that we need to preserve the value of SCL and
+ * SDA outputs as well (which may be different from the
+ * values read back from IOC_CONTROL).
+ */
+static u_int force_ones;
+
+static void ioc_setscl(void *data, int state)
+{
+ u_int ioc_control = ioc_readb(IOC_CONTROL) & ~(SCL | SDA);
+ u_int ones = force_ones;
+
+ if (state)
+ ones |= SCL;
+ else
+ ones &= ~SCL;
+
+ force_ones = ones;
+
+ ioc_writeb(ioc_control | ones, IOC_CONTROL);
+}
+
+static void ioc_setsda(void *data, int state)
+{
+ u_int ioc_control = ioc_readb(IOC_CONTROL) & ~(SCL | SDA);
+ u_int ones = force_ones;
+
+ if (state)
+ ones |= SDA;
+ else
+ ones &= ~SDA;
+
+ force_ones = ones;
+
+ ioc_writeb(ioc_control | ones, IOC_CONTROL);
+}
+
+static int ioc_getscl(void *data)
+{
+ return (ioc_readb(IOC_CONTROL) & SCL) != 0;
+}
+
+static int ioc_getsda(void *data)
+{
+ return (ioc_readb(IOC_CONTROL) & SDA) != 0;
+}
+
+static struct i2c_algo_bit_data ioc_data = {
+ .setsda = ioc_setsda,
+ .setscl = ioc_setscl,
+ .getsda = ioc_getsda,
+ .getscl = ioc_getscl,
+ .udelay = 80,
+ .timeout = 100
+};
+
+static struct i2c_adapter ioc_ops = {
+ .id = I2C_HW_B_IOC,
+ .algo_data = &ioc_data,
+};
+
+static int __init i2c_ioc_init(void)
+{
+ force_ones = FORCE_ONES | SCL | SDA;
+
+ return i2c_bit_add_bus(&ioc_ops);
+}
+
+__initcall(i2c_ioc_init);