patch-2.4.10 linux/drivers/i2c/i2c-adap-ite.c

• Lines: 320
• Date: Sun Sep 9 10:43:02 2001
• Orig file: v2.4.9/linux/drivers/i2c/i2c-adap-ite.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.9/linux/drivers/i2c/i2c-adap-ite.c linux/drivers/i2c/i2c-adap-ite.c
@@ -0,0 +1,319 @@
+/*
+   -------------------------------------------------------------------------
+   i2c-adap-ite.c i2c-hw access for the IIC peripheral on the ITE MIPS system
+   -------------------------------------------------------------------------
+   Hai-Pao Fan, MontaVista Software, Inc.
+   hpfan@mvista.com or source@mvista.com
+
+   Copyright 2001 MontaVista Software Inc.
+
+   ----------------------------------------------------------------------------
+   This file was highly leveraged from i2c-elektor.c, which was created
+   by Simon G. Vogl and Hans Berglund:
+
+ 
+     Copyright (C) 1995-97 Simon G. Vogl
+                   1998-99 Hans Berglund
+
+    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., 675 Mass Ave, Cambridge, MA 02139, USA.		     */
+/* ------------------------------------------------------------------------- */
+
+/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even
+   Frodo Looijaard <frodol@dds.nl> */
+
+#include <linux/kernel.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/malloc.h>
+#include <linux/version.h>
+#include <linux/init.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-algo-ite.h>
+#include <linux/i2c-adap-ite.h>
+#include "i2c-ite.h"
+
+#define DEFAULT_BASE  0x14014030
+#define ITE_IIC_IO_SIZE	0x40
+#define DEFAULT_IRQ   0
+#define DEFAULT_CLOCK 0x1b0e	/* default 16MHz/(27+14) = 400KHz */
+#define DEFAULT_OWN   0x55
+
+static int base  = 0;
+static int irq   = 0;
+static int clock = 0;
+static int own   = 0;
+
+static int i2c_debug=0;
+static struct iic_ite gpi;
+#if (LINUX_VERSION_CODE < 0x020301)
+static struct wait_queue *iic_wait = NULL;
+#else
+static wait_queue_head_t iic_wait;
+#endif
+static int iic_pending;
+
+/* ----- global defines -----------------------------------------------	*/
+#define DEB(x)	if (i2c_debug>=1) x
+#define DEB2(x) if (i2c_debug>=2) x
+#define DEB3(x) if (i2c_debug>=3) x
+#define DEBE(x)	x	/* error messages 				*/
+
+
+/* ----- local functions ----------------------------------------------	*/
+
+static void iic_ite_setiic(void *data, int ctl, short val)
+{
+        unsigned long j = jiffies + 10;
+
+	DEB3(printk(" Write 0x%02x to 0x%x\n",(unsigned short)val, ctl&0xff));
+	DEB3({while (jiffies < j) schedule();}) 
+	outw(val,ctl);
+}
+
+static short iic_ite_getiic(void *data, int ctl)
+{
+	short val;
+
+	val = inw(ctl);
+	DEB3(printk("Read 0x%02x from 0x%x\n",(unsigned short)val, ctl&0xff));  
+	return (val);
+}
+
+/* Return our slave address.  This is the address
+ * put on the I2C bus when another master on the bus wants to address us
+ * as a slave
+ */
+static int iic_ite_getown(void *data)
+{
+	return (gpi.iic_own);
+}
+
+
+static int iic_ite_getclock(void *data)
+{
+	return (gpi.iic_clock);
+}
+
+
+#if 0
+static void iic_ite_sleep(unsigned long timeout)
+{
+	schedule_timeout( timeout * HZ);
+}
+#endif
+
+
+/* Put this process to sleep.  We will wake up when the
+ * IIC controller interrupts.
+ */
+static void iic_ite_waitforpin(void) {
+
+   int timeout = 2;
+
+   /* If interrupts are enabled (which they are), then put the process to
+    * sleep.  This process will be awakened by two events -- either the
+    * the IIC peripheral interrupts or the timeout expires. 
+    * If interrupts are not enabled then delay for a reasonable amount 
+    * of time and return.
+    */
+   if (gpi.iic_irq > 0) {
+	cli();
+	if (iic_pending == 0) {
+		interruptible_sleep_on_timeout(&iic_wait, timeout*HZ );
+	} else
+		iic_pending = 0;
+	sti();
+   } else {
+      udelay(100);
+   }
+}
+
+
+static void iic_ite_handler(int this_irq, void *dev_id, struct pt_regs *regs) 
+{
+	
+   iic_pending = 1;
+
+   DEB2(printk("iic_ite_handler: in interrupt handler\n"));
+   wake_up_interruptible(&iic_wait);
+}
+
+
+/* Lock the region of memory where I/O registers exist.  Request our
+ * interrupt line and register its associated handler.
+ */
+static int iic_hw_resrc_init(void)
+{
+  	if (check_region(gpi.iic_base, ITE_IIC_IO_SIZE) < 0 ) {
+   	   return -ENODEV;
+  	} else {
+  	   request_region(gpi.iic_base, ITE_IIC_IO_SIZE, 
+		"i2c (i2c bus adapter)");
+  	}
+	if (gpi.iic_irq > 0) {
+	   if (request_irq(gpi.iic_irq, iic_ite_handler, 0, "ITE IIC", 0) < 0) {
+	      gpi.iic_irq = 0;
+	   } else
+	      DEB3(printk("Enabled IIC IRQ %d\n", gpi.iic_irq));
+	      enable_irq(gpi.iic_irq);
+	}
+	return 0;
+}
+
+
+static void iic_ite_release(void)
+{
+	if (gpi.iic_irq > 0) {
+		disable_irq(gpi.iic_irq);
+		free_irq(gpi.iic_irq, 0);
+	}
+	release_region(gpi.iic_base , 2);
+}
+
+
+static int iic_ite_reg(struct i2c_client *client)
+{
+	return 0;
+}
+
+
+static int iic_ite_unreg(struct i2c_client *client)
+{
+	return 0;
+}
+
+
+static void iic_ite_inc_use(struct i2c_adapter *adap)
+{
+#ifdef MODULE
+	MOD_INC_USE_COUNT;
+#endif
+}
+
+
+static void iic_ite_dec_use(struct i2c_adapter *adap)
+{
+#ifdef MODULE
+	MOD_DEC_USE_COUNT;
+#endif
+}
+
+
+/* ------------------------------------------------------------------------
+ * Encapsulate the above functions in the correct operations structure.
+ * This is only done when more than one hardware adapter is supported.
+ */
+static struct i2c_algo_iic_data iic_ite_data = {
+	NULL,
+	iic_ite_setiic,
+	iic_ite_getiic,
+	iic_ite_getown,
+	iic_ite_getclock,
+	iic_ite_waitforpin,
+	80, 80, 100,		/*	waits, timeout */
+};
+
+static struct i2c_adapter iic_ite_ops = {
+	"ITE IIC adapter",
+	I2C_HW_I_IIC,
+	NULL,
+	&iic_ite_data,
+	iic_ite_inc_use,
+	iic_ite_dec_use,
+	iic_ite_reg,
+	iic_ite_unreg,
+};
+
+/* Called when the module is loaded.  This function starts the
+ * cascade of calls up through the heirarchy of i2c modules (i.e. up to the
+ *  algorithm layer and into to the core layer)
+ */
+static int __init iic_ite_init(void) 
+{
+
+	struct iic_ite *piic = &gpi;
+
+	printk(KERN_INFO "Initialize ITE IIC adapter module\n");
+	if (base == 0)
+		piic->iic_base = DEFAULT_BASE;
+	else
+		piic->iic_base = base;
+
+	if (irq == 0)
+		piic->iic_irq = DEFAULT_IRQ;
+	else
+		piic->iic_irq = irq;
+
+	if (clock == 0)
+		piic->iic_clock = DEFAULT_CLOCK;
+	else
+		piic->iic_clock = clock;
+
+	if (own == 0)
+		piic->iic_own = DEFAULT_OWN;
+	else
+		piic->iic_own = own;
+
+	iic_ite_data.data = (void *)piic;
+#if (LINUX_VERSION_CODE >= 0x020301)
+	init_waitqueue_head(&iic_wait);
+#endif
+	if (iic_hw_resrc_init() == 0) {
+		if (i2c_iic_add_bus(&iic_ite_ops) < 0)
+			return -ENODEV;
+	} else {
+		return -ENODEV;
+	}
+	printk(KERN_INFO " found device at %#x irq %d.\n", 
+		piic->iic_base, piic->iic_irq);
+	return 0;
+}
+
+
+static void iic_ite_exit(void)
+{
+	i2c_iic_del_bus(&iic_ite_ops);
+        iic_ite_release();
+}
+
+EXPORT_NO_SYMBOLS;
+
+/* If modules is NOT defined when this file is compiled, then the MODULE_*
+ * macros will resolve to nothing
+ */
+MODULE_AUTHOR("MontaVista Software <www.mvista.com>");
+MODULE_DESCRIPTION("I2C-Bus adapter routines for ITE IIC bus adapter");
+
+MODULE_PARM(base, "i");
+MODULE_PARM(irq, "i");
+MODULE_PARM(clock, "i");
+MODULE_PARM(own, "i");
+MODULE_PARM(i2c_debug,"i");
+
+
+/* Called when module is loaded or when kernel is intialized.
+ * If MODULES is defined when this file is compiled, then this function will
+ * resolve to init_module (the function called when insmod is invoked for a
+ * module).  Otherwise, this function is called early in the boot, when the
+ * kernel is intialized.  Check out /include/init.h to see how this works.
+ */
+module_init(iic_ite_init);
+
+/* Resolves to module_cleanup when MODULES is defined. */
+module_exit(iic_ite_exit);