-/*
+/* linux/drivers/i2c/scx200_acb.c
+
Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com>
National Semiconductor SCx200 ACCESS.bus support
- Also supports the AMD CS5535 and AMD CS5536
-
+
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/module.h>
#include <linux/smp_lock.h>
#include <linux/pci.h>
#include <linux/delay.h>
-#include <linux/mutex.h>
#include <asm/io.h>
#include <linux/scx200.h>
module_param_array(base, int, NULL, 0);
MODULE_PARM_DESC(base, "Base addresses for the ACCESS.bus controllers");
-#define POLL_TIMEOUT (HZ/5)
+#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,
};
/* Physical interface */
-struct scx200_acb_iface {
+struct scx200_acb_iface
+{
struct scx200_acb_iface *next;
struct i2c_adapter adapter;
unsigned base;
- struct mutex mutex;
+ struct semaphore sem;
/* State machine data */
enum scx200_acb_state state;
u8 *ptr;
char needs_reset;
unsigned len;
-
- /* PCI device info */
- struct pci_dev *pdev;
- int bar;
};
/* Register Definitions */
#define ACBSDA (iface->base + 0)
#define ACBST (iface->base + 1)
#define ACBST_SDAST 0x40 /* SDA Status */
-#define ACBST_BER 0x20
+#define ACBST_BER 0x20
#define ACBST_NEGACK 0x10 /* Negative Acknowledge */
#define ACBST_STASTR 0x08 /* Stall After Start */
#define ACBST_MASTER 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 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
{
const char *errmsg;
- dev_dbg(&iface->adapter.dev, "state %s, status = 0x%02x\n",
- scx200_acb_state_name[iface->state], status);
+ DBG("state %s, status = 0x%02x\n",
+ scx200_acb_state_name[iface->state], status);
if (status & ACBST_BER) {
errmsg = "bus error";
errmsg = "not master";
goto error;
}
- if (status & ACBST_NEGACK) {
- dev_dbg(&iface->adapter.dev, "negative ack 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);
-
- /* Reset the status register */
- outb(0, ACBST);
- return;
- }
+ if (status & ACBST_NEGACK)
+ goto negack;
switch (iface->state) {
case state_idle:
case state_repeat_start:
outb(inb(ACBCTL1) | ACBCTL1_START, ACBCTL1);
/* fallthrough */
-
+
case state_quick:
if (iface->address_byte & 1) {
- if (iface->len == 1)
+ if (iface->len == 1)
outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1);
else
outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1);
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->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;
+ u8 status = 0;
unsigned long timeout;
timeout = jiffies + POLL_TIMEOUT;
- while (1) {
+ while (time_before(jiffies, timeout)) {
status = inb(ACBST);
-
- /* Reset the status register to avoid the hang */
- outb(0, ACBST);
-
if ((status & (ACBST_SDAST|ACBST_BER|ACBST_NEGACK)) != 0) {
scx200_acb_machine(iface, status);
return;
}
- if (time_after(jiffies, timeout))
- break;
- cpu_relax();
- cond_resched();
+ msleep(10);
}
- 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;
+ 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 */
+ frequency: 16 clock cycles */
outb(0x70, ACBCTL2);
/* Polling mode */
outb(0, ACBCTL1);
}
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)
+ 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;
switch (size) {
case I2C_SMBUS_QUICK:
- len = 0;
- buffer = NULL;
- break;
-
+ len = 0;
+ buffer = NULL;
+ break;
case I2C_SMBUS_BYTE:
- len = 1;
- buffer = rw ? &data->byte : &command;
- break;
-
+ 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;
-
+ len = 1;
+ buffer = &data->byte;
+ break;
case I2C_SMBUS_WORD_DATA:
len = 2;
- cur_word = cpu_to_le16(data->word);
- buffer = (u8 *)&cur_word;
+ cur_word = cpu_to_le16(data->word);
+ buffer = (u8 *)&cur_word;
break;
-
case I2C_SMBUS_I2C_BLOCK_DATA:
if (rw == I2C_SMBUS_READ)
data->block[0] = I2C_SMBUS_BLOCK_MAX; /* For now */
- len = data->block[0];
+ len = data->block[0];
if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
return -EINVAL;
- buffer = &data->block[1];
+ buffer = &data->block[1];
break;
-
default:
- return -EINVAL;
+ return -EINVAL;
}
- dev_dbg(&adapter->dev,
- "size=%d, address=0x%x, command=0x%x, len=%d, read=%d\n",
- size, address, command, len, rw);
+ 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_dbg(&adapter->dev, "zero length read\n");
+ dev_warn(&adapter->dev, "zero length read\n");
return -EINVAL;
}
- mutex_lock(&iface->mutex);
+ if (len && !buffer) {
+ dev_warn(&adapter->dev, "nonzero length but no buffer\n");
+ return -EFAULT;
+ }
+
+ down(&iface->sem);
- iface->address_byte = (address << 1) | rw;
+ iface->address_byte = address<<1;
+ if (rw == I2C_SMBUS_READ)
+ iface->address_byte |= 1;
iface->command = command;
iface->ptr = buffer;
iface->len = len;
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;
- mutex_unlock(&iface->mutex);
+ up(&iface->sem);
if (rc == 0 && size == I2C_SMBUS_WORD_DATA && rw == I2C_SMBUS_READ)
- data->word = le16_to_cpu(cur_word);
+ data->word = le16_to_cpu(cur_word);
#ifdef DEBUG
- dev_dbg(&adapter->dev, "transfer done, result: %d", rc);
+ DBG(": transfer done, result: %d", rc);
if (buffer) {
int i;
printk(" data:");
};
static struct scx200_acb_iface *scx200_acb_list;
-static DECLARE_MUTEX(scx200_acb_list_mutex);
-static __init int scx200_acb_probe(struct scx200_acb_iface *iface)
+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 */
+ frequency: 16 clock cycles */
outb(0x70, ACBCTL2);
if (inb(ACBCTL2) != 0x70) {
- pr_debug(NAME ": ACBCTL2 readback failed\n");
+ DBG("ACBCTL2 readback failed\n");
return -ENXIO;
}
val = inb(ACBCTL1);
if (val) {
- pr_debug(NAME ": disabled, but ACBCTL1=0x%02x\n",
- val);
+ DBG("disabled, but ACBCTL1=0x%02x\n", val);
return -ENXIO;
}
val = inb(ACBCTL1);
if ((val & ACBCTL1_NMINTE) != ACBCTL1_NMINTE) {
- pr_debug(NAME ": enabled, but NMINTE won't be set, "
- "ACBCTL1=0x%02x\n", val);
+ DBG("enabled, but NMINTE won't be set, ACBCTL1=0x%02x\n", val);
return -ENXIO;
}
return 0;
}
-static __init struct scx200_acb_iface *scx200_create_iface(const char *text,
- int index)
+static int __init scx200_acb_create(int base, int index)
{
struct scx200_acb_iface *iface;
struct i2c_adapter *adapter;
+ int rc = 0;
iface = kzalloc(sizeof(*iface), GFP_KERNEL);
if (!iface) {
printk(KERN_ERR NAME ": can't allocate memory\n");
- return NULL;
+ rc = -ENOMEM;
+ goto errout;
}
adapter = &iface->adapter;
i2c_set_adapdata(adapter, iface);
- snprintf(adapter->name, I2C_NAME_SIZE, "%s ACB%d", text, index);
+ snprintf(adapter->name, I2C_NAME_SIZE, "SCx200 ACB%d", index);
adapter->owner = THIS_MODULE;
adapter->id = I2C_HW_SMBUS_SCX200;
adapter->algo = &scx200_acb_algorithm;
adapter->class = I2C_CLASS_HWMON;
- mutex_init(&iface->mutex);
-
- return iface;
-}
-
-static int __init scx200_acb_create(struct scx200_acb_iface *iface)
-{
- struct i2c_adapter *adapter;
- int rc;
+ init_MUTEX(&iface->sem);
- adapter = &iface->adapter;
+ if (!request_region(base, 8, adapter->name)) {
+ 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) {
- printk(KERN_WARNING NAME ": probe failed\n");
- return rc;
+ dev_warn(&adapter->dev, "probe failed\n");
+ goto errout;
}
scx200_acb_reset(iface);
if (i2c_add_adapter(adapter) < 0) {
- printk(KERN_ERR NAME ": failed to register\n");
- return -ENODEV;
+ dev_err(&adapter->dev, "failed to register\n");
+ rc = -ENODEV;
+ goto errout;
}
- down(&scx200_acb_list_mutex);
+ lock_kernel();
iface->next = scx200_acb_list;
scx200_acb_list = iface;
- up(&scx200_acb_list_mutex);
+ unlock_kernel();
return 0;
-}
-
-static __init int scx200_create_pci(const char *text, struct pci_dev *pdev,
- int bar)
-{
- struct scx200_acb_iface *iface;
- int rc;
-
- iface = scx200_create_iface(text, 0);
-
- if (iface == NULL)
- return -ENOMEM;
-
- iface->pdev = pdev;
- iface->bar = bar;
-
- pci_enable_device_bars(iface->pdev, 1 << iface->bar);
-
- rc = pci_request_region(iface->pdev, iface->bar, iface->adapter.name);
- if (rc != 0) {
- printk(KERN_ERR NAME ": can't allocate PCI BAR %d\n",
- iface->bar);
- goto errout_free;
- }
-
- iface->base = pci_resource_start(iface->pdev, iface->bar);
- rc = scx200_acb_create(iface);
-
- if (rc == 0)
- return 0;
-
- pci_release_region(iface->pdev, iface->bar);
- pci_dev_put(iface->pdev);
- errout_free:
- kfree(iface);
- return rc;
-}
-
-static int __init scx200_create_isa(const char *text, unsigned long base,
- int index)
-{
- struct scx200_acb_iface *iface;
- int rc;
-
- iface = scx200_create_iface(text, index);
-
- if (iface == NULL)
- return -ENOMEM;
-
- if (request_region(base, 8, iface->adapter.name) == 0) {
- printk(KERN_ERR NAME ": can't allocate io 0x%lx-0x%lx\n",
- base, base + 8 - 1);
- rc = -EBUSY;
- goto errout_free;
+ errout:
+ if (iface) {
+ if (iface->base)
+ release_region(iface->base, 8);
+ kfree(iface);
}
-
- iface->base = base;
- rc = scx200_acb_create(iface);
-
- if (rc == 0)
- return 0;
-
- release_region(base, 8);
- errout_free:
- kfree(iface);
return rc;
}
-/* Driver data is an index into the scx200_data array that indicates
- * the name and the BAR where the I/O address resource is located. ISA
- * devices are flagged with a bar value of -1 */
-
-static struct pci_device_id scx200_pci[] = {
- { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE),
- .driver_data = 0 },
- { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE),
- .driver_data = 0 },
- { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_ISA),
- .driver_data = 1 },
- { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA),
- .driver_data = 2 }
+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 struct {
- const char *name;
- int bar;
-} scx200_data[] = {
- { "SCx200", -1 },
- { "CS5535", 0 },
- { "CS5536", 0 }
-};
-
-static __init int scx200_scan_pci(void)
-{
- int data, dev;
- int rc = -ENODEV;
- struct pci_dev *pdev;
-
- for(dev = 0; dev < ARRAY_SIZE(scx200_pci); dev++) {
- pdev = pci_get_device(scx200_pci[dev].vendor,
- scx200_pci[dev].device, NULL);
-
- if (pdev == NULL)
- continue;
-
- data = scx200_pci[dev].driver_data;
-
- /* if .bar is greater or equal to zero, this is a
- * PCI device - otherwise, we assume
- that the ports are ISA based
- */
-
- if (scx200_data[data].bar >= 0)
- rc = scx200_create_pci(scx200_data[data].name, pdev,
- scx200_data[data].bar);
- else {
- int i;
-
- for (i = 0; i < MAX_DEVICES; ++i) {
- if (base[i] == 0)
- continue;
-
- rc = scx200_create_isa(scx200_data[data].name,
- base[i],
- i);
- }
- }
-
- break;
- }
-
- return rc;
-}
-
static int __init scx200_acb_init(void)
{
+ int i;
int rc;
pr_debug(NAME ": NatSemi SCx200 ACCESS.bus Driver\n");
- rc = scx200_scan_pci();
+ /* Verify that this really is a SCx200 processor */
+ if (pci_dev_present(scx200) == 0)
+ return -ENODEV;
- /* If at least one bus was created, init must succeed */
+ 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;
-
- down(&scx200_acb_list_mutex);
+ lock_kernel();
while ((iface = scx200_acb_list) != NULL) {
scx200_acb_list = iface->next;
- up(&scx200_acb_list_mutex);
+ unlock_kernel();
i2c_del_adapter(&iface->adapter);
-
- if (iface->pdev) {
- pci_release_region(iface->pdev, iface->bar);
- pci_dev_put(iface->pdev);
- }
- else
- release_region(iface->base, 8);
-
+ release_region(iface->base, 8);
kfree(iface);
- down(&scx200_acb_list_mutex);
+ lock_kernel();
}
- up(&scx200_acb_list_mutex);
+ 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:
+*/
+
git://git.onelab.eu / linux-2.6.git / blobdiff