Initial import

1 files changed, 343 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-elektor.c b/drivers/i2c/busses/i2c-elektor.c
new file mode 100644
index 000000000..92e8c0ce1
--- /dev/null
+++ b/drivers/i2c/busses/i2c-elektor.c
@@ -0,0 +1,343 @@
+/* ------------------------------------------------------------------------- */
+/* i2c-elektor.c i2c-hw access for PCF8584 style isa bus adaptes             */
+/* ------------------------------------------------------------------------- */
+/*   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.			     */
+/* ------------------------------------------------------------------------- */
+
+/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even
+   Frodo Looijaard <frodol@dds.nl> */
+
+/* Partially rewriten by Oleg I. Vdovikin for mmapped support of
+   for Alpha Processor Inc. UP-2000(+) boards */
+
+#include <linux/kernel.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+
+#include <linux/isa.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-pcf.h>
+#include <linux/io.h>
+
+#include <asm/irq.h>
+
+#include "../algos/i2c-algo-pcf.h"
+
+#define DEFAULT_BASE 0x330
+
+static int base;
+static u8 __iomem *base_iomem;
+
+static int irq;
+static int clock  = 0x1c;
+static int own    = 0x55;
+static int mmapped;
+
+/* vdovikin: removed static struct i2c_pcf_isa gpi; code -
+  this module in real supports only one device, due to missing arguments
+  in some functions, called from the algo-pcf module. Sometimes it's
+  need to be rewriten - but for now just remove this for simpler reading */
+
+static wait_queue_head_t pcf_wait;
+static int pcf_pending;
+static spinlock_t lock;
+
+static struct i2c_adapter pcf_isa_ops;
+
+/* ----- local functions ----------------------------------------------	*/
+
+static void pcf_isa_setbyte(void *data, int ctl, int val)
+{
+	u8 __iomem *address = ctl ? (base_iomem + 1) : base_iomem;
+
+	/* enable irq if any specified for serial operation */
+	if (ctl && irq && (val & I2C_PCF_ESO)) {
+		val |= I2C_PCF_ENI;
+	}
+
+	pr_debug("%s: Write %p 0x%02X\n", pcf_isa_ops.name, address, val);
+	iowrite8(val, address);
+#ifdef __alpha__
+	/* API UP2000 needs some hardware fudging to make the write stick */
+	iowrite8(val, address);
+#endif
+}
+
+static int pcf_isa_getbyte(void *data, int ctl)
+{
+	u8 __iomem *address = ctl ? (base_iomem + 1) : base_iomem;
+	int val = ioread8(address);
+
+	pr_debug("%s: Read %p 0x%02X\n", pcf_isa_ops.name, address, val);
+	return (val);
+}
+
+static int pcf_isa_getown(void *data)
+{
+	return (own);
+}
+
+
+static int pcf_isa_getclock(void *data)
+{
+	return (clock);
+}
+
+static void pcf_isa_waitforpin(void *data)
+{
+	DEFINE_WAIT(wait);
+	int timeout = 2;
+	unsigned long flags;
+
+	if (irq > 0) {
+		spin_lock_irqsave(&lock, flags);
+		if (pcf_pending == 0) {
+			spin_unlock_irqrestore(&lock, flags);
+			prepare_to_wait(&pcf_wait, &wait, TASK_INTERRUPTIBLE);
+			if (schedule_timeout(timeout*HZ)) {
+				spin_lock_irqsave(&lock, flags);
+				if (pcf_pending == 1) {
+					pcf_pending = 0;
+				}
+				spin_unlock_irqrestore(&lock, flags);
+			}
+			finish_wait(&pcf_wait, &wait);
+		} else {
+			pcf_pending = 0;
+			spin_unlock_irqrestore(&lock, flags);
+		}
+	} else {
+		udelay(100);
+	}
+}
+
+
+static irqreturn_t pcf_isa_handler(int this_irq, void *dev_id) {
+	spin_lock(&lock);
+	pcf_pending = 1;
+	spin_unlock(&lock);
+	wake_up_interruptible(&pcf_wait);
+	return IRQ_HANDLED;
+}
+
+
+static int pcf_isa_init(void)
+{
+	spin_lock_init(&lock);
+	if (!mmapped) {
+		if (!request_region(base, 2, pcf_isa_ops.name)) {
+			printk(KERN_ERR "%s: requested I/O region (%#x:2) is "
+			       "in use\n", pcf_isa_ops.name, base);
+			return -ENODEV;
+		}
+		base_iomem = ioport_map(base, 2);
+		if (!base_iomem) {
+			printk(KERN_ERR "%s: remap of I/O region %#x failed\n",
+			       pcf_isa_ops.name, base);
+			release_region(base, 2);
+			return -ENODEV;
+		}
+	} else {
+		if (!request_mem_region(base, 2, pcf_isa_ops.name)) {
+			printk(KERN_ERR "%s: requested memory region (%#x:2) "
+			       "is in use\n", pcf_isa_ops.name, base);
+			return -ENODEV;
+		}
+		base_iomem = ioremap(base, 2);
+		if (base_iomem == NULL) {
+			printk(KERN_ERR "%s: remap of memory region %#x "
+			       "failed\n", pcf_isa_ops.name, base);
+			release_mem_region(base, 2);
+			return -ENODEV;
+		}
+	}
+	pr_debug("%s: registers %#x remapped to %p\n", pcf_isa_ops.name, base,
+		 base_iomem);
+
+	if (irq > 0) {
+		if (request_irq(irq, pcf_isa_handler, 0, pcf_isa_ops.name,
+				NULL) < 0) {
+			printk(KERN_ERR "%s: Request irq%d failed\n",
+			       pcf_isa_ops.name, irq);
+			irq = 0;
+		} else
+			enable_irq(irq);
+	}
+	return 0;
+}
+
+/* ------------------------------------------------------------------------
+ * 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_pcf_data pcf_isa_data = {
+	.setpcf	    = pcf_isa_setbyte,
+	.getpcf	    = pcf_isa_getbyte,
+	.getown	    = pcf_isa_getown,
+	.getclock   = pcf_isa_getclock,
+	.waitforpin = pcf_isa_waitforpin,
+};
+
+static struct i2c_adapter pcf_isa_ops = {
+	.owner		= THIS_MODULE,
+	.class		= I2C_CLASS_HWMON | I2C_CLASS_SPD,
+	.algo_data	= &pcf_isa_data,
+	.name		= "i2c-elektor",
+};
+
+static int elektor_match(struct device *dev, unsigned int id)
+{
+#ifdef __alpha__
+	/* check to see we have memory mapped PCF8584 connected to the
+	Cypress cy82c693 PCI-ISA bridge as on UP2000 board */
+	if (base == 0) {
+		struct pci_dev *cy693_dev;
+
+		cy693_dev = pci_get_device(PCI_VENDOR_ID_CONTAQ,
+					   PCI_DEVICE_ID_CONTAQ_82C693, NULL);
+		if (cy693_dev) {
+			unsigned char config;
+			/* yeap, we've found cypress, let's check config */
+			if (!pci_read_config_byte(cy693_dev, 0x47, &config)) {
+
+				dev_dbg(dev, "found cy82c693, config "
+					"register 0x47 = 0x%02x\n", config);
+
+				/* UP2000 board has this register set to 0xe1,
+				   but the most significant bit as seems can be
+				   reset during the proper initialisation
+				   sequence if guys from API decides to do that
+				   (so, we can even enable Tsunami Pchip
+				   window for the upper 1 Gb) */
+
+				/* so just check for ROMCS at 0xe0000,
+				   ROMCS enabled for writes
+				   and external XD Bus buffer in use. */
+				if ((config & 0x7f) == 0x61) {
+					/* seems to be UP2000 like board */
+					base = 0xe0000;
+					mmapped = 1;
+					/* UP2000 drives ISA with
+					   8.25 MHz (PCI/4) clock
+					   (this can be read from cypress) */
+					clock = I2C_PCF_CLK | I2C_PCF_TRNS90;
+					dev_info(dev, "found API UP2000 like "
+						 "board, will probe PCF8584 "
+						 "later\n");
+				}
+			}
+			pci_dev_put(cy693_dev);
+		}
+	}
+#endif
+
+	/* sanity checks for mmapped I/O */
+	if (mmapped && base < 0xc8000) {
+		dev_err(dev, "incorrect base address (%#x) specified "
+		       "for mmapped I/O\n", base);
+		return 0;
+	}
+
+	if (base == 0) {
+		base = DEFAULT_BASE;
+	}
+	return 1;
+}
+
+static int elektor_probe(struct device *dev, unsigned int id)
+{
+	init_waitqueue_head(&pcf_wait);
+	if (pcf_isa_init())
+		return -ENODEV;
+	pcf_isa_ops.dev.parent = dev;
+	if (i2c_pcf_add_bus(&pcf_isa_ops) < 0)
+		goto fail;
+
+	dev_info(dev, "found device at %#x\n", base);
+
+	return 0;
+
+ fail:
+	if (irq > 0) {
+		disable_irq(irq);
+		free_irq(irq, NULL);
+	}
+
+	if (!mmapped) {
+		ioport_unmap(base_iomem);
+		release_region(base, 2);
+	} else {
+		iounmap(base_iomem);
+		release_mem_region(base, 2);
+	}
+	return -ENODEV;
+}
+
+static int elektor_remove(struct device *dev, unsigned int id)
+{
+	i2c_del_adapter(&pcf_isa_ops);
+
+	if (irq > 0) {
+		disable_irq(irq);
+		free_irq(irq, NULL);
+	}
+
+	if (!mmapped) {
+		ioport_unmap(base_iomem);
+		release_region(base, 2);
+	} else {
+		iounmap(base_iomem);
+		release_mem_region(base, 2);
+	}
+
+	return 0;
+}
+
+static struct isa_driver i2c_elektor_driver = {
+	.match		= elektor_match,
+	.probe		= elektor_probe,
+	.remove		= elektor_remove,
+	.driver = {
+		.owner	= THIS_MODULE,
+		.name	= "i2c-elektor",
+	},
+};
+
+static int __init i2c_pcfisa_init(void)
+{
+	return isa_register_driver(&i2c_elektor_driver, 1);
+}
+
+static void __exit i2c_pcfisa_exit(void)
+{
+	isa_unregister_driver(&i2c_elektor_driver);
+}
+
+MODULE_AUTHOR("Hans Berglund <hb@spacetec.no>");
+MODULE_DESCRIPTION("I2C-Bus adapter routines for PCF8584 ISA bus adapter");
+MODULE_LICENSE("GPL");
+
+module_param(base, int, 0);
+module_param(irq, int, 0);
+module_param(clock, int, 0);
+module_param(own, int, 0);
+module_param(mmapped, int, 0);
+
+module_init(i2c_pcfisa_init);
+module_exit(i2c_pcfisa_exit);