Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 557 insertions, 0 deletions

diff --git a/drivers/i2c/busses/scx200_acb.c b/drivers/i2c/busses/scx200_acb.c
new file mode 100644
index 000000000000..1c4159a93623
--- /dev/null
+++ b/drivers/i2c/busses/scx200_acb.c
@@ -0,0 +1,557 @@
+/*  linux/drivers/i2c/scx200_acb.c 
+
+    Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com>
+
+    National Semiconductor SCx200 ACCESS.bus support
+    
+    Based on i2c-keywest.c which is:
+        Copyright (c) 2001 Benjamin Herrenschmidt <benh@kernel.crashing.org>
+        Copyright (c) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
+    
+    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.
+
+*/
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/smp_lock.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+#include <linux/scx200.h>
+
+#define NAME "scx200_acb"
+
+MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>");
+MODULE_DESCRIPTION("NatSemi SCx200 ACCESS.bus Driver");
+MODULE_LICENSE("GPL");
+
+#define MAX_DEVICES 4
+static int base[MAX_DEVICES] = { 0x820, 0x840 };
+module_param_array(base, int, NULL, 0);
+MODULE_PARM_DESC(base, "Base addresses for the ACCESS.bus controllers");
+
+#ifdef DEBUG
+#define DBG(x...) printk(KERN_DEBUG NAME ": " x)
+#else
+#define DBG(x...)
+#endif
+
+/* The hardware supports interrupt driven mode too, but I haven't
+   implemented that. */
+#define POLLED_MODE 1
+#define POLL_TIMEOUT (HZ)
+
+enum scx200_acb_state {
+        state_idle,
+        state_address,
+        state_command,
+        state_repeat_start,
+        state_quick,
+        state_read,
+        state_write,
+};
+
+static const char *scx200_acb_state_name[] = {
+        "idle",
+        "address",
+        "command",
+        "repeat_start",
+        "quick",
+        "read",
+        "write",
+};
+
+/* Physical interface */
+struct scx200_acb_iface
+{
+        struct scx200_acb_iface *next;
+        struct i2c_adapter adapter;
+        unsigned base;
+        struct semaphore sem;
+
+        /* State machine data */
+        enum scx200_acb_state state;
+        int result;
+        u8 address_byte;
+        u8 command;
+        u8 *ptr;
+        char needs_reset;
+        unsigned len;
+};
+
+/* Register Definitions */
+#define ACBSDA          (iface->base + 0)
+#define ACBST           (iface->base + 1)
+#define    ACBST_SDAST          0x40 /* SDA Status */
+#define    ACBST_BER            0x20 
+#define    ACBST_NEGACK         0x10 /* Negative Acknowledge */
+#define    ACBST_STASTR         0x08 /* Stall After Start */
+#define    ACBST_MASTER         0x02
+#define ACBCST          (iface->base + 2)
+#define    ACBCST_BB            0x02
+#define ACBCTL1         (iface->base + 3)
+#define    ACBCTL1_STASTRE      0x80
+#define    ACBCTL1_NMINTE       0x40
+#define    ACBCTL1_ACK          0x10
+#define    ACBCTL1_STOP         0x02
+#define    ACBCTL1_START        0x01
+#define ACBADDR         (iface->base + 4)
+#define ACBCTL2         (iface->base + 5)
+#define    ACBCTL2_ENABLE       0x01
+
+/************************************************************************/
+
+static void scx200_acb_machine(struct scx200_acb_iface *iface, u8 status)
+{
+        const char *errmsg;
+
+        DBG("state %s, status = 0x%02x\n", 
+            scx200_acb_state_name[iface->state], status);
+
+        if (status & ACBST_BER) {
+                errmsg = "bus error";
+                goto error;
+        }
+        if (!(status & ACBST_MASTER)) {
+                errmsg = "not master";
+                goto error;
+        }
+        if (status & ACBST_NEGACK)
+                goto negack;
+
+        switch (iface->state) {
+        case state_idle:
+                dev_warn(&iface->adapter.dev, "interrupt in idle state\n");
+                break;
+
+        case state_address:
+                /* Do a pointer write first */
+                outb(iface->address_byte & ~1, ACBSDA);
+
+                iface->state = state_command;
+                break;
+
+        case state_command:
+                outb(iface->command, ACBSDA);
+
+                if (iface->address_byte & 1)
+                        iface->state = state_repeat_start;
+                else
+                        iface->state = state_write;
+                break;
+
+        case state_repeat_start:
+                outb(inb(ACBCTL1) | ACBCTL1_START, ACBCTL1);
+                /* fallthrough */
+                
+        case state_quick:
+                if (iface->address_byte & 1) {
+                        if (iface->len == 1) 
+                                outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1);
+                        else
+                                outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1);
+                        outb(iface->address_byte, ACBSDA);
+
+                        iface->state = state_read;
+                } else {
+                        outb(iface->address_byte, ACBSDA);
+
+                        iface->state = state_write;
+                }
+                break;
+
+        case state_read:
+                /* Set ACK if receiving the last byte */
+                if (iface->len == 1)
+                        outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1);
+                else
+                        outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1);
+
+                *iface->ptr++ = inb(ACBSDA);
+                --iface->len;
+
+                if (iface->len == 0) {
+                        iface->result = 0;
+                        iface->state = state_idle;
+                        outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
+                }
+
+                break;
+
+        case state_write:
+                if (iface->len == 0) {
+                        iface->result = 0;
+                        iface->state = state_idle;
+                        outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
+                        break;
+                }
+                
+                outb(*iface->ptr++, ACBSDA);
+                --iface->len;
+                
+                break;
+        }
+
+        return;
+
+ negack:
+        DBG("negative acknowledge in state %s\n", 
+            scx200_acb_state_name[iface->state]);
+
+        iface->state = state_idle;
+        iface->result = -ENXIO;
+
+        outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
+        outb(ACBST_STASTR | ACBST_NEGACK, ACBST);
+        return;
+
+ error:
+        dev_err(&iface->adapter.dev, "%s in state %s\n", errmsg,
+                scx200_acb_state_name[iface->state]);
+
+        iface->state = state_idle;
+        iface->result = -EIO;
+        iface->needs_reset = 1;
+}
+
+static void scx200_acb_timeout(struct scx200_acb_iface *iface) 
+{
+        dev_err(&iface->adapter.dev, "timeout in state %s\n",
+                scx200_acb_state_name[iface->state]);
+
+        iface->state = state_idle;
+        iface->result = -EIO;
+        iface->needs_reset = 1;
+}
+
+#ifdef POLLED_MODE
+static void scx200_acb_poll(struct scx200_acb_iface *iface)
+{
+        u8 status = 0;
+        unsigned long timeout;
+
+        timeout = jiffies + POLL_TIMEOUT;
+        while (time_before(jiffies, timeout)) {
+                status = inb(ACBST);
+                if ((status & (ACBST_SDAST|ACBST_BER|ACBST_NEGACK)) != 0) {
+                        scx200_acb_machine(iface, status);
+                        return;
+                }
+                msleep(10);
+        }
+
+        scx200_acb_timeout(iface);
+}
+#endif /* POLLED_MODE */
+
+static void scx200_acb_reset(struct scx200_acb_iface *iface)
+{
+        /* Disable the ACCESS.bus device and Configure the SCL
+           frequency: 16 clock cycles */
+        outb(0x70, ACBCTL2);
+        /* Polling mode */
+        outb(0, ACBCTL1);
+        /* Disable slave address */
+        outb(0, ACBADDR);
+        /* Enable the ACCESS.bus device */
+        outb(inb(ACBCTL2) | ACBCTL2_ENABLE, ACBCTL2);
+        /* Free STALL after START */
+        outb(inb(ACBCTL1) & ~(ACBCTL1_STASTRE | ACBCTL1_NMINTE), ACBCTL1);
+        /* Send a STOP */
+        outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
+        /* Clear BER, NEGACK and STASTR bits */
+        outb(ACBST_BER | ACBST_NEGACK | ACBST_STASTR, ACBST);
+        /* Clear BB bit */
+        outb(inb(ACBCST) | ACBCST_BB, ACBCST);
+}
+
+static s32 scx200_acb_smbus_xfer(struct i2c_adapter *adapter,
+                                u16 address, unsigned short flags,      
+                                char rw, u8 command, int size, 
+                                union i2c_smbus_data *data)
+{
+        struct scx200_acb_iface *iface = i2c_get_adapdata(adapter);
+        int len;
+        u8 *buffer;
+        u16 cur_word;
+        int rc;
+
+        switch (size) {
+        case I2C_SMBUS_QUICK:
+                len = 0;
+                buffer = NULL;
+                break;
+        case I2C_SMBUS_BYTE:
+                if (rw == I2C_SMBUS_READ) {
+                        len = 1;
+                        buffer = &data->byte;
+                } else {
+                        len = 1;
+                        buffer = &command;
+                }
+                break;
+        case I2C_SMBUS_BYTE_DATA:
+                len = 1;
+                buffer = &data->byte;
+                break;
+        case I2C_SMBUS_WORD_DATA:
+                len = 2;
+                cur_word = cpu_to_le16(data->word);
+                buffer = (u8 *)&cur_word;
+                break;
+        case I2C_SMBUS_BLOCK_DATA:
+                len = data->block[0];
+                buffer = &data->block[1];
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        DBG("size=%d, address=0x%x, command=0x%x, len=%d, read=%d\n",
+            size, address, command, len, rw == I2C_SMBUS_READ);
+
+        if (!len && rw == I2C_SMBUS_READ) {
+                dev_warn(&adapter->dev, "zero length read\n");
+                return -EINVAL;
+        }
+
+        if (len && !buffer) {
+                dev_warn(&adapter->dev, "nonzero length but no buffer\n");
+                return -EFAULT;
+        }
+
+        down(&iface->sem);
+
+        iface->address_byte = address<<1;
+        if (rw == I2C_SMBUS_READ)
+                iface->address_byte |= 1;
+        iface->command = command;
+        iface->ptr = buffer;
+        iface->len = len;
+        iface->result = -EINVAL;
+        iface->needs_reset = 0;
+
+        outb(inb(ACBCTL1) | ACBCTL1_START, ACBCTL1);
+
+        if (size == I2C_SMBUS_QUICK || size == I2C_SMBUS_BYTE)
+                iface->state = state_quick;
+        else
+                iface->state = state_address;
+
+#ifdef POLLED_MODE
+        while (iface->state != state_idle)
+                scx200_acb_poll(iface);
+#else /* POLLED_MODE */
+#error Interrupt driven mode not implemented
+#endif /* POLLED_MODE */        
+
+        if (iface->needs_reset)
+                scx200_acb_reset(iface);
+
+        rc = iface->result;
+
+        up(&iface->sem);
+
+        if (rc == 0 && size == I2C_SMBUS_WORD_DATA && rw == I2C_SMBUS_READ)
+                data->word = le16_to_cpu(cur_word);
+
+#ifdef DEBUG
+        DBG(": transfer done, result: %d", rc);
+        if (buffer) {
+                int i;
+                printk(" data:");
+                for (i = 0; i < len; ++i)
+                        printk(" %02x", buffer[i]);
+        }
+        printk("\n");
+#endif
+
+        return rc;
+}
+
+static u32 scx200_acb_func(struct i2c_adapter *adapter)
+{
+        return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
+               I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
+               I2C_FUNC_SMBUS_BLOCK_DATA;
+}
+
+/* For now, we only handle combined mode (smbus) */
+static struct i2c_algorithm scx200_acb_algorithm = {
+        .name           = "NatSemi SCx200 ACCESS.bus",
+        .id             = I2C_ALGO_SMBUS,
+        .smbus_xfer     = scx200_acb_smbus_xfer,
+        .functionality  = scx200_acb_func,
+};
+
+static struct scx200_acb_iface *scx200_acb_list;
+
+static int scx200_acb_probe(struct scx200_acb_iface *iface)
+{
+        u8 val;
+
+        /* Disable the ACCESS.bus device and Configure the SCL
+           frequency: 16 clock cycles */
+        outb(0x70, ACBCTL2);
+
+        if (inb(ACBCTL2) != 0x70) {
+                DBG("ACBCTL2 readback failed\n");
+                return -ENXIO;
+        }
+
+        outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1);
+
+        val = inb(ACBCTL1);
+        if (val) {
+                DBG("disabled, but ACBCTL1=0x%02x\n", val);
+                return -ENXIO;
+        }
+
+        outb(inb(ACBCTL2) | ACBCTL2_ENABLE, ACBCTL2);
+
+        outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1);
+
+        val = inb(ACBCTL1);
+        if ((val & ACBCTL1_NMINTE) != ACBCTL1_NMINTE) {
+                DBG("enabled, but NMINTE won't be set, ACBCTL1=0x%02x\n", val);
+                return -ENXIO;
+        }
+
+        return 0;
+}
+
+static int  __init scx200_acb_create(int base, int index)
+{
+        struct scx200_acb_iface *iface;
+        struct i2c_adapter *adapter;
+        int rc = 0;
+        char description[64];
+
+        iface = kmalloc(sizeof(*iface), GFP_KERNEL);
+        if (!iface) {
+                printk(KERN_ERR NAME ": can't allocate memory\n");
+                rc = -ENOMEM;
+                goto errout;
+        }
+
+        memset(iface, 0, sizeof(*iface));
+        adapter = &iface->adapter;
+        i2c_set_adapdata(adapter, iface);
+        snprintf(adapter->name, I2C_NAME_SIZE, "SCx200 ACB%d", index);
+        adapter->owner = THIS_MODULE;
+        adapter->id = I2C_ALGO_SMBUS;
+        adapter->algo = &scx200_acb_algorithm;
+        adapter->class = I2C_CLASS_HWMON;
+
+        init_MUTEX(&iface->sem);
+
+        snprintf(description, sizeof(description), "NatSemi SCx200 ACCESS.bus [%s]", adapter->name);
+        if (request_region(base, 8, description) == 0) {
+                dev_err(&adapter->dev, "can't allocate io 0x%x-0x%x\n",
+                        base, base + 8-1);
+                rc = -EBUSY;
+                goto errout;
+        }
+        iface->base = base;
+
+        rc = scx200_acb_probe(iface);
+        if (rc) {
+                dev_warn(&adapter->dev, "probe failed\n");
+                goto errout;
+        }
+
+        scx200_acb_reset(iface);
+
+        if (i2c_add_adapter(adapter) < 0) {
+                dev_err(&adapter->dev, "failed to register\n");
+                rc = -ENODEV;
+                goto errout;
+        }
+
+        lock_kernel();
+        iface->next = scx200_acb_list;
+        scx200_acb_list = iface;
+        unlock_kernel();
+
+        return 0;
+
+ errout:
+        if (iface) {
+                if (iface->base)
+                        release_region(iface->base, 8);
+                kfree(iface);
+        }
+        return rc;
+}
+
+static struct pci_device_id scx200[] = {
+        { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) },
+        { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) },
+        { },
+};
+
+static int __init scx200_acb_init(void)
+{
+        int i;
+        int rc;
+
+        pr_debug(NAME ": NatSemi SCx200 ACCESS.bus Driver\n");
+
+        /* Verify that this really is a SCx200 processor */
+        if (pci_dev_present(scx200) == 0)
+                return -ENODEV;
+
+        rc = -ENXIO;
+        for (i = 0; i < MAX_DEVICES; ++i) {
+                if (base[i] > 0)
+                        rc = scx200_acb_create(base[i], i);
+        }
+        if (scx200_acb_list)
+                return 0;
+        return rc;
+}
+
+static void __exit scx200_acb_cleanup(void)
+{
+        struct scx200_acb_iface *iface;
+        lock_kernel();
+        while ((iface = scx200_acb_list) != NULL) {
+                scx200_acb_list = iface->next;
+                unlock_kernel();
+
+                i2c_del_adapter(&iface->adapter);
+                release_region(iface->base, 8);
+                kfree(iface);
+                lock_kernel();
+        }
+        unlock_kernel();
+}
+
+module_init(scx200_acb_init);
+module_exit(scx200_acb_cleanup);
+
+/*
+    Local variables:
+        compile-command: "make -k -C ../.. SUBDIRS=drivers/i2c modules"
+        c-basic-offset: 8
+    End:
+*/
+