1 files changed, 295 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-elektor.c b/drivers/i2c/busses/i2c-elektor.c
new file mode 100644
index 000000000000..0a7720000a0c
--- /dev/null
+++ b/drivers/i2c/busses/i2c-elektor.c
@@ -0,0 +1,295 @@
+/* ------------------------------------------------------------------------- */
+/* 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.
+
+    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> */
+
+/* Partialy rewriten by Oleg I. Vdovikin for mmapped support of 
+   for Alpha Processor Inc. UP-2000(+) boards */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-algo-pcf.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#include "../algos/i2c-algo-pcf.h"
+
+#define DEFAULT_BASE 0x330
+
+static int base;
+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;
+
+/* ----- local functions ---------------------------------------------- */
+
+static void pcf_isa_setbyte(void *data, int ctl, int val)
+{
+        int address = ctl ? (base + 1) : base;
+
+        /* enable irq if any specified for serial operation */
+        if (ctl && irq && (val & I2C_PCF_ESO)) {
+                val |= I2C_PCF_ENI;
+        }
+
+        pr_debug("i2c-elektor: Write 0x%X 0x%02X\n", address, val & 255);
+
+        switch (mmapped) {
+        case 0: /* regular I/O */
+                outb(val, address);
+                break;
+        case 2: /* double mapped I/O needed for UP2000 board,
+                   I don't know why this... */
+                writeb(val, (void *)address);
+                /* fall */
+        case 1: /* memory mapped I/O */
+                writeb(val, (void *)address);
+                break;
+        }
+}
+
+static int pcf_isa_getbyte(void *data, int ctl)
+{
+        int address = ctl ? (base + 1) : base;
+        int val = mmapped ? readb((void *)address) : inb(address);
+
+        pr_debug("i2c-elektor: Read 0x%X 0x%02X\n", 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) {
+        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, struct pt_regs *regs) {
+        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, "i2c (isa bus adapter)")) {
+                        printk(KERN_ERR
+                               "i2c-elektor: requested I/O region (0x%X:2) "
+                               "is in use.\n", base);
+                        return -ENODEV;
+                }
+        }
+        if (irq > 0) {
+                if (request_irq(irq, pcf_isa_handler, 0, "PCF8584", NULL) < 0) {
+                        printk(KERN_ERR "i2c-elektor: Request irq%d failed\n", 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,
+        .udelay     = 10,
+        .mdelay     = 10,
+        .timeout    = 100,
+};
+
+static struct i2c_adapter pcf_isa_ops = {
+        .owner          = THIS_MODULE,
+        .class          = I2C_CLASS_HWMON,
+        .id             = I2C_HW_P_ELEK,
+        .algo_data      = &pcf_isa_data,
+        .name           = "PCF8584 ISA adapter",
+};
+
+static int __init i2c_pcfisa_init(void) 
+{
+#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) {
+                        char config;
+                        /* yeap, we've found cypress, let's check config */
+                        if (!pci_read_config_byte(cy693_dev, 0x47, &config)) {
+                                
+                                pr_debug("i2c-elektor: 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;
+                                        /* I don't know why we need to
+                                           write twice */
+                                        mmapped = 2;
+                                        /* UP2000 drives ISA with
+                                           8.25 MHz (PCI/4) clock
+                                           (this can be read from cypress) */
+                                        clock = I2C_PCF_CLK | I2C_PCF_TRNS90;
+                                        printk(KERN_INFO "i2c-elektor: 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) {
+                printk(KERN_ERR "i2c-elektor: incorrect base address (0x%0X) specified for mmapped I/O.\n", base);
+                return -ENODEV;
+        }
+
+        printk(KERN_INFO "i2c-elektor: i2c pcf8584-isa adapter driver\n");
+
+        if (base == 0) {
+                base = DEFAULT_BASE;
+        }
+
+        init_waitqueue_head(&pcf_wait);
+        if (pcf_isa_init())
+                return -ENODEV;
+        if (i2c_pcf_add_bus(&pcf_isa_ops) < 0)
+                goto fail;
+        
+        printk(KERN_ERR "i2c-elektor: found device at %#x.\n", base);
+
+        return 0;
+
+ fail:
+        if (irq > 0) {
+                disable_irq(irq);
+                free_irq(irq, NULL);
+        }
+
+        if (!mmapped)
+                release_region(base , 2);
+        return -ENODEV;
+}
+
+static void i2c_pcfisa_exit(void)
+{
+        i2c_pcf_del_bus(&pcf_isa_ops);
+
+        if (irq > 0) {
+                disable_irq(irq);
+                free_irq(irq, NULL);
+        }
+
+        if (!mmapped)
+                release_region(base , 2);
+}
+
+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);