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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-24 05:04:00 +08:00
linux-next/drivers/i2c/busses/scx200_acb.c
Linus Torvalds e6b5be2be4 Driver core patches for 3.19-rc1
Here's the set of driver core patches for 3.19-rc1.
 
 They are dominated by the removal of the .owner field in platform
 drivers.  They touch a lot of files, but they are "simple" changes, just
 removing a line in a structure.
 
 Other than that, a few minor driver core and debugfs changes.  There are
 some ath9k patches coming in through this tree that have been acked by
 the wireless maintainers as they relied on the debugfs changes.
 
 Everything has been in linux-next for a while.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core update from Greg KH:
 "Here's the set of driver core patches for 3.19-rc1.

  They are dominated by the removal of the .owner field in platform
  drivers.  They touch a lot of files, but they are "simple" changes,
  just removing a line in a structure.

  Other than that, a few minor driver core and debugfs changes.  There
  are some ath9k patches coming in through this tree that have been
  acked by the wireless maintainers as they relied on the debugfs
  changes.

  Everything has been in linux-next for a while"

* tag 'driver-core-3.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (324 commits)
  Revert "ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries"
  fs: debugfs: add forward declaration for struct device type
  firmware class: Deletion of an unnecessary check before the function call "vunmap"
  firmware loader: fix hung task warning dump
  devcoredump: provide a one-way disable function
  device: Add dev_<level>_once variants
  ath: ath9k: use debugfs_create_devm_seqfile() helper for seq_file entries
  ath: use seq_file api for ath9k debugfs files
  debugfs: add helper function to create device related seq_file
  drivers/base: cacheinfo: remove noisy error boot message
  Revert "core: platform: add warning if driver has no owner"
  drivers: base: support cpu cache information interface to userspace via sysfs
  drivers: base: add cpu_device_create to support per-cpu devices
  topology: replace custom attribute macros with standard DEVICE_ATTR*
  cpumask: factor out show_cpumap into separate helper function
  driver core: Fix unbalanced device reference in drivers_probe
  driver core: fix race with userland in device_add()
  sysfs/kernfs: make read requests on pre-alloc files use the buffer.
  sysfs/kernfs: allow attributes to request write buffer be pre-allocated.
  fs: sysfs: return EGBIG on write if offset is larger than file size
  ...
2014-12-14 16:10:09 -08:00

609 lines
13 KiB
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.
*/
#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/pci.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/scx200.h>
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
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");
#define POLL_TIMEOUT (HZ/5)
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 mutex mutex;
/* 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;
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";
goto error;
}
if (!(status & ACBST_MASTER)) {
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;
}
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 _next_ byte will be the last one */
if (iface->len == 2)
outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1);
else
outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1);
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:
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;
error:
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_poll(struct scx200_acb_iface *iface)
{
u8 status;
unsigned long timeout;
timeout = jiffies + POLL_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;
}
if (time_after(jiffies, timeout))
break;
cpu_relax();
cond_resched();
}
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;
}
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:
len = 1;
buffer = rw ? &data->byte : &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_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;
}
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_dbg(&adapter->dev, "zero length read\n");
return -EINVAL;
}
mutex_lock(&iface->mutex);
iface->address_byte = (address << 1) | rw;
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;
while (iface->state != state_idle)
scx200_acb_poll(iface);
if (iface->needs_reset)
scx200_acb_reset(iface);
rc = iface->result;
mutex_unlock(&iface->mutex);
if (rc == 0 && size == I2C_SMBUS_WORD_DATA && rw == I2C_SMBUS_READ)
data->word = le16_to_cpu(cur_word);
#ifdef DEBUG
dev_dbg(&adapter->dev, "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_I2C_BLOCK;
}
/* For now, we only handle combined mode (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 */
outb(0x70, ACBCTL2);
if (inb(ACBCTL2) != 0x70) {
pr_debug("ACBCTL2 readback failed\n");
return -ENXIO;
}
outb(inb(ACBCTL1) | ACBCTL1_NMINTE, ACBCTL1);
val = inb(ACBCTL1);
if (val) {
pr_debug("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) {
pr_debug("enabled, but NMINTE won't be set, ACBCTL1=0x%02x\n",
val);
return -ENXIO;
}
return 0;
}
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;
iface = kzalloc(sizeof(*iface), GFP_KERNEL);
if (!iface)
return NULL;
adapter = &iface->adapter;
i2c_set_adapdata(adapter, iface);
snprintf(adapter->name, sizeof(adapter->name), "%s ACB%d", text, index);
adapter->owner = THIS_MODULE;
adapter->algo = &scx200_acb_algorithm;
adapter->class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
adapter->dev.parent = dev;
mutex_init(&iface->mutex);
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) {
pr_warn("probe failed\n");
return rc;
}
scx200_acb_reset(iface);
if (i2c_add_adapter(adapter) < 0) {
pr_err("failed to register\n");
return -ENODEV;
}
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);
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;
}
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 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",
},
.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 __init void scx200_scan_isa(void)
{
int i;
if (!pci_dev_present(scx200_isa))
return;
for (i = 0; i < MAX_DEVICES; ++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;
/* 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;
platform_driver_unregister(&scx200_pci_driver);
mutex_lock(&scx200_acb_list_mutex);
while ((iface = scx200_acb_list) != NULL) {
scx200_acb_list = iface->next;
mutex_unlock(&scx200_acb_list_mutex);
scx200_cleanup_iface(iface);
mutex_lock(&scx200_acb_list_mutex);
}
mutex_unlock(&scx200_acb_list_mutex);
}
module_init(scx200_acb_init);
module_exit(scx200_acb_cleanup);