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Diffstat (limited to 'drivers/i2c/busses/scx200_acb.c')
-rw-r--r--drivers/i2c/busses/scx200_acb.c433
1 files changed, 245 insertions, 188 deletions
diff --git a/drivers/i2c/busses/scx200_acb.c b/drivers/i2c/busses/scx200_acb.c
index a18bdd9aa7b..ff3f5747e43 100644
--- a/drivers/i2c/busses/scx200_acb.c
+++ b/drivers/i2c/busses/scx200_acb.c
@@ -1,45 +1,47 @@
-/* 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.
-
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#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/platform_device.h>
#include <linux/delay.h>
-#include <asm/io.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/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_ALIAS("platform:cs5535-smb");
MODULE_LICENSE("GPL");
#define MAX_DEVICES 4
@@ -47,16 +49,7 @@ 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)
+#define POLL_TIMEOUT (HZ/5)
enum scx200_acb_state {
state_idle,
@@ -79,12 +72,11 @@ static const char *scx200_acb_state_name[] = {
};
/* Physical interface */
-struct scx200_acb_iface
-{
+struct scx200_acb_iface {
struct scx200_acb_iface *next;
struct i2c_adapter adapter;
unsigned base;
- struct semaphore sem;
+ struct mutex mutex;
/* State machine data */
enum scx200_acb_state state;
@@ -100,7 +92,7 @@ struct scx200_acb_iface
#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
@@ -109,9 +101,9 @@ struct scx200_acb_iface
#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
@@ -122,8 +114,8 @@ 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);
+ dev_dbg(&iface->adapter.dev, "state %s, status = 0x%02x\n",
+ scx200_acb_state_name[iface->state], status);
if (status & ACBST_BER) {
errmsg = "bus error";
@@ -133,8 +125,20 @@ static void scx200_acb_machine(struct scx200_acb_iface *iface, u8 status)
errmsg = "not master";
goto error;
}
- if (status & ACBST_NEGACK)
- goto negack;
+ 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;
+ }
switch (iface->state) {
case state_idle:
@@ -160,10 +164,10 @@ static void scx200_acb_machine(struct scx200_acb_iface *iface, u8 status)
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);
@@ -178,21 +182,21 @@ static void scx200_acb_machine(struct scx200_acb_iface *iface, u8 status)
break;
case state_read:
- /* Set ACK if receiving the last byte */
- if (iface->len == 1)
+ /* Set ACK if _next_ byte will be the last one */
+ if (iface->len == 2)
outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1);
else
outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1);
- *iface->ptr++ = inb(ACBSDA);
- --iface->len;
-
- if (iface->len == 0) {
+ if (iface->len == 1) {
iface->result = 0;
iface->state = state_idle;
outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
}
+ *iface->ptr++ = inb(ACBSDA);
+ --iface->len;
+
break;
case state_write:
@@ -202,69 +206,60 @@ static void scx200_acb_machine(struct scx200_acb_iface *iface, u8 status)
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]);
+ dev_err(&iface->adapter.dev,
+ "%s in state %s (addr=0x%02x, len=%d, status=0x%02x)\n", errmsg,
+ scx200_acb_state_name[iface->state], iface->address_byte,
+ iface->len, status);
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;
+ u8 status;
unsigned long timeout;
timeout = jiffies + POLL_TIMEOUT;
- while (time_before(jiffies, timeout)) {
+ while (1) {
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;
}
- msleep(10);
+ if (time_after(jiffies, timeout))
+ break;
+ cpu_relax();
+ cond_resched();
}
- scx200_acb_timeout(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;
}
-#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);
@@ -283,9 +278,9 @@ static void scx200_acb_reset(struct scx200_acb_iface *iface)
}
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;
@@ -295,53 +290,49 @@ static s32 scx200_acb_smbus_xfer(struct i2c_adapter *adapter,
switch (size) {
case I2C_SMBUS_QUICK:
- len = 0;
- buffer = NULL;
- break;
+ 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;
+ len = 1;
+ buffer = rw ? &data->byte : &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_BLOCK_DATA:
- len = data->block[0];
- buffer = &data->block[1];
+
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ len = data->block[0];
+ if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
+ return -EINVAL;
+ buffer = &data->block[1];
break;
+
default:
- return -EINVAL;
+ return -EINVAL;
}
- DBG("size=%d, address=0x%x, command=0x%x, len=%d, read=%d\n",
- size, address, command, len, rw == I2C_SMBUS_READ);
+ dev_dbg(&adapter->dev,
+ "size=%d, address=0x%x, command=0x%x, len=%d, read=%d\n",
+ size, address, command, len, rw);
if (!len && rw == I2C_SMBUS_READ) {
- dev_warn(&adapter->dev, "zero length read\n");
+ dev_dbg(&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);
+ mutex_lock(&iface->mutex);
- iface->address_byte = address<<1;
- if (rw == I2C_SMBUS_READ)
- iface->address_byte |= 1;
+ iface->address_byte = (address << 1) | rw;
iface->command = command;
iface->ptr = buffer;
iface->len = len;
@@ -355,25 +346,21 @@ static s32 scx200_acb_smbus_xfer(struct i2c_adapter *adapter,
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);
+ mutex_unlock(&iface->mutex);
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
- DBG(": transfer done, result: %d", rc);
+ dev_dbg(&adapter->dev, "transfer done, result: %d", rc);
if (buffer) {
int i;
printk(" data:");
@@ -390,29 +377,28 @@ 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;
+ I2C_FUNC_SMBUS_I2C_BLOCK;
}
/* For now, we only handle combined mode (smbus) */
-static struct i2c_algorithm scx200_acb_algorithm = {
- .name = "NatSemi SCx200 ACCESS.bus",
- .id = I2C_ALGO_SMBUS,
+static const struct i2c_algorithm scx200_acb_algorithm = {
.smbus_xfer = scx200_acb_smbus_xfer,
.functionality = scx200_acb_func,
};
static struct scx200_acb_iface *scx200_acb_list;
+static DEFINE_MUTEX(scx200_acb_list_mutex);
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) {
- DBG("ACBCTL2 readback failed\n");
+ pr_debug("ACBCTL2 readback failed\n");
return -ENXIO;
}
@@ -420,7 +406,7 @@ static int scx200_acb_probe(struct scx200_acb_iface *iface)
val = inb(ACBCTL1);
if (val) {
- DBG("disabled, but ACBCTL1=0x%02x\n", val);
+ pr_debug("disabled, but ACBCTL1=0x%02x\n", val);
return -ENXIO;
}
@@ -430,127 +416,198 @@ static int scx200_acb_probe(struct scx200_acb_iface *iface)
val = inb(ACBCTL1);
if ((val & ACBCTL1_NMINTE) != ACBCTL1_NMINTE) {
- DBG("enabled, but NMINTE won't be set, ACBCTL1=0x%02x\n", val);
+ pr_debug("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)
+static struct scx200_acb_iface *scx200_create_iface(const char *text,
+ struct device *dev, 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));
+ iface = kzalloc(sizeof(*iface), GFP_KERNEL);
+ if (!iface)
+ return NULL;
+
adapter = &iface->adapter;
i2c_set_adapdata(adapter, iface);
- snprintf(adapter->name, I2C_NAME_SIZE, "SCx200 ACB%d", index);
+ snprintf(adapter->name, sizeof(adapter->name), "%s ACB%d", text, index);
adapter->owner = THIS_MODULE;
- adapter->id = I2C_ALGO_SMBUS;
adapter->algo = &scx200_acb_algorithm;
- adapter->class = I2C_CLASS_HWMON;
+ adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+ adapter->dev.parent = dev;
- init_MUTEX(&iface->sem);
+ mutex_init(&iface->mutex);
- 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;
+ return iface;
+}
+
+static int scx200_acb_create(struct scx200_acb_iface *iface)
+{
+ struct i2c_adapter *adapter;
+ int rc;
+
+ adapter = &iface->adapter;
rc = scx200_acb_probe(iface);
if (rc) {
- dev_warn(&adapter->dev, "probe failed\n");
- goto errout;
+ pr_warn("probe failed\n");
+ return rc;
}
scx200_acb_reset(iface);
if (i2c_add_adapter(adapter) < 0) {
- dev_err(&adapter->dev, "failed to register\n");
- rc = -ENODEV;
- goto errout;
+ pr_err("failed to register\n");
+ return -ENODEV;
}
- lock_kernel();
- iface->next = scx200_acb_list;
- scx200_acb_list = iface;
- unlock_kernel();
+ if (!adapter->dev.parent) {
+ /* If there's no dev, we're tracking (ISA) ifaces manually */
+ mutex_lock(&scx200_acb_list_mutex);
+ iface->next = scx200_acb_list;
+ scx200_acb_list = iface;
+ mutex_unlock(&scx200_acb_list_mutex);
+ }
return 0;
+}
+
+static struct scx200_acb_iface *scx200_create_dev(const char *text,
+ unsigned long base, int index, struct device *dev)
+{
+ struct scx200_acb_iface *iface;
+ int rc;
+
+ iface = scx200_create_iface(text, dev, index);
- errout:
- if (iface) {
- if (iface->base)
- release_region(iface->base, 8);
- kfree(iface);
+ if (iface == NULL)
+ return NULL;
+
+ if (!request_region(base, 8, iface->adapter.name)) {
+ pr_err("can't allocate io 0x%lx-0x%lx\n", base, base + 8 - 1);
+ goto errout_free;
}
- return rc;
+
+ iface->base = base;
+ rc = scx200_acb_create(iface);
+
+ if (rc == 0)
+ return iface;
+
+ release_region(base, 8);
+ errout_free:
+ kfree(iface);
+ return NULL;
+}
+
+static int scx200_probe(struct platform_device *pdev)
+{
+ struct scx200_acb_iface *iface;
+ struct resource *res;
+
+ res = platform_get_resource(pdev, IORESOURCE_IO, 0);
+ if (!res) {
+ dev_err(&pdev->dev, "can't fetch device resource info\n");
+ return -ENODEV;
+ }
+
+ iface = scx200_create_dev("CS5535", res->start, 0, &pdev->dev);
+ if (!iface)
+ return -EIO;
+
+ dev_info(&pdev->dev, "SCx200 device '%s' registered\n",
+ iface->adapter.name);
+ platform_set_drvdata(pdev, iface);
+
+ return 0;
}
-static struct pci_device_id scx200[] = {
+static void scx200_cleanup_iface(struct scx200_acb_iface *iface)
+{
+ i2c_del_adapter(&iface->adapter);
+ release_region(iface->base, 8);
+ kfree(iface);
+}
+
+static int scx200_remove(struct platform_device *pdev)
+{
+ struct scx200_acb_iface *iface;
+
+ iface = platform_get_drvdata(pdev);
+ scx200_cleanup_iface(iface);
+
+ return 0;
+}
+
+static struct platform_driver scx200_pci_driver = {
+ .driver = {
+ .name = "cs5535-smb",
+ .owner = THIS_MODULE,
+ },
+ .probe = scx200_probe,
+ .remove = scx200_remove,
+};
+
+static const struct pci_device_id scx200_isa[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SCx200_BRIDGE) },
{ PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_SC1100_BRIDGE) },
- { },
+ { 0, }
};
-static int __init scx200_acb_init(void)
+static __init void scx200_scan_isa(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;
+ if (!pci_dev_present(scx200_isa))
+ return;
- rc = -ENXIO;
for (i = 0; i < MAX_DEVICES; ++i) {
- if (base[i] > 0)
- rc = scx200_acb_create(base[i], i);
+ if (base[i] == 0)
+ continue;
+
+ /* XXX: should we care about failures? */
+ scx200_create_dev("SCx200", base[i], i, NULL);
}
+}
+
+static int __init scx200_acb_init(void)
+{
+ pr_debug("NatSemi SCx200 ACCESS.bus Driver\n");
+
+ /* First scan for ISA-based devices */
+ scx200_scan_isa(); /* XXX: should we care about errors? */
+
+ /* If at least one bus was created, init must succeed */
if (scx200_acb_list)
return 0;
- return rc;
+
+ /* No ISA devices; register the platform driver for PCI-based devices */
+ return platform_driver_register(&scx200_pci_driver);
}
static void __exit scx200_acb_cleanup(void)
{
struct scx200_acb_iface *iface;
- lock_kernel();
+
+ platform_driver_unregister(&scx200_pci_driver);
+
+ mutex_lock(&scx200_acb_list_mutex);
while ((iface = scx200_acb_list) != NULL) {
scx200_acb_list = iface->next;
- unlock_kernel();
+ mutex_unlock(&scx200_acb_list_mutex);
+
+ scx200_cleanup_iface(iface);
- i2c_del_adapter(&iface->adapter);
- release_region(iface->base, 8);
- kfree(iface);
- lock_kernel();
+ mutex_lock(&scx200_acb_list_mutex);
}
- unlock_kernel();
+ mutex_unlock(&scx200_acb_list_mutex);
}
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:
-*/
-
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-12-14 11:48:27 +0000