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Merge branch 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging

Browse source 
* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  i2c: I2C bus multiplexer driver pca954x
  i2c: Multiplexed I2C bus core support
  i2c: Use a separate mutex for userspace client lists
  i2c: Make i2c_default_probe self-sufficient
  i2c: Drop dummy variable
  i2c: Move adapter locking helpers to i2c-core
  V4L/DVB: Use custom I2C probing function mechanism
  i2c: Add support for custom probe function
  i2c-dev: Use memdup_user
  i2c-dev: Remove unnecessary kmalloc casts
This commit is contained in:
Linus Torvalds 2010-08-12 10:06:29 -07:00
commit 1c00650c23
22 changed files with 805 additions and 116 deletions
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2
Documentation/i2c/instantiating-devices
View file

@ -102,7 +102,7 @@ static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev)
memset(&i2c_info, 0, sizeof(struct i2c_board_info));
strlcpy(i2c_info.name, "isp1301_pnx", I2C_NAME_SIZE);
isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info,
normal_i2c);
normal_i2c, NULL);
i2c_put_adapter(i2c_adap);
(...)
}

13
drivers/i2c/Kconfig
View file

@ -47,6 +47,19 @@ config I2C_CHARDEV
This support is also available as a module. If so, the module
will be called i2c-dev.
config I2C_MUX
tristate "I2C bus multiplexing support"
depends on EXPERIMENTAL
help
Say Y here if you want the I2C core to support the ability to
handle multiplexed I2C bus topologies, by presenting each
multiplexed segment as a I2C adapter.
This support is also available as a module. If so, the module
will be called i2c-mux.
source drivers/i2c/muxes/Kconfig
config I2C_HELPER_AUTO
bool "Autoselect pertinent helper modules"
default y

3
drivers/i2c/Makefile
View file

@ -6,7 +6,8 @@ obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o
obj-$(CONFIG_I2C) += i2c-core.o
obj-$(CONFIG_I2C_SMBUS) += i2c-smbus.o
obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o
obj-y += algos/ busses/
obj-$(CONFIG_I2C_MUX) += i2c-mux.o
obj-y += algos/ busses/ muxes/
ifeq ($(CONFIG_I2C_DEBUG_CORE),y)
EXTRA_CFLAGS += -DDEBUG

158
drivers/i2c/i2c-core.c
View file

@ -20,7 +20,9 @@
/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>.
All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
Jean Delvare <khali@linux-fr.org> */
Jean Delvare <khali@linux-fr.org>
Mux support by Rodolfo Giometti <giometti@enneenne.com> and
Michael Lawnick <michael.lawnick.ext@nsn.com> */
#include <linux/module.h>
#include <linux/kernel.h>
@ -423,12 +425,88 @@ static int __i2c_check_addr_busy(struct device *dev, void *addrp)
return 0;
}
/* walk up mux tree */
static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr)
{
int result;
result = device_for_each_child(&adapter->dev, &addr,
__i2c_check_addr_busy);
if (!result && i2c_parent_is_i2c_adapter(adapter))
result = i2c_check_mux_parents(
to_i2c_adapter(adapter->dev.parent), addr);
return result;
}
/* recurse down mux tree */
static int i2c_check_mux_children(struct device *dev, void *addrp)
{
int result;
if (dev->type == &i2c_adapter_type)
result = device_for_each_child(dev, addrp,
i2c_check_mux_children);
else
result = __i2c_check_addr_busy(dev, addrp);
return result;
}
static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr)
{
return device_for_each_child(&adapter->dev, &addr,
__i2c_check_addr_busy);
int result = 0;
if (i2c_parent_is_i2c_adapter(adapter))
result = i2c_check_mux_parents(
to_i2c_adapter(adapter->dev.parent), addr);
if (!result)
result = device_for_each_child(&adapter->dev, &addr,
i2c_check_mux_children);
return result;
}
/**
* i2c_lock_adapter - Get exclusive access to an I2C bus segment
* @adapter: Target I2C bus segment
*/
void i2c_lock_adapter(struct i2c_adapter *adapter)
{
if (i2c_parent_is_i2c_adapter(adapter))
i2c_lock_adapter(to_i2c_adapter(adapter->dev.parent));
else
rt_mutex_lock(&adapter->bus_lock);
}
EXPORT_SYMBOL_GPL(i2c_lock_adapter);
/**
* i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment
* @adapter: Target I2C bus segment
*/
static int i2c_trylock_adapter(struct i2c_adapter *adapter)
{
if (i2c_parent_is_i2c_adapter(adapter))
return i2c_trylock_adapter(to_i2c_adapter(adapter->dev.parent));
else
return rt_mutex_trylock(&adapter->bus_lock);
}
/**
* i2c_unlock_adapter - Release exclusive access to an I2C bus segment
* @adapter: Target I2C bus segment
*/
void i2c_unlock_adapter(struct i2c_adapter *adapter)
{
if (i2c_parent_is_i2c_adapter(adapter))
i2c_unlock_adapter(to_i2c_adapter(adapter->dev.parent));
else
rt_mutex_unlock(&adapter->bus_lock);
}
EXPORT_SYMBOL_GPL(i2c_unlock_adapter);
/**
* i2c_new_device - instantiate an i2c device
* @adap: the adapter managing the device
@ -633,9 +711,9 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr,
return -EINVAL;
/* Keep track of the added device */
i2c_lock_adapter(adap);
mutex_lock(&adap->userspace_clients_lock);
list_add_tail(&client->detected, &adap->userspace_clients);
i2c_unlock_adapter(adap);
mutex_unlock(&adap->userspace_clients_lock);
dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device",
info.type, info.addr);
@ -674,7 +752,7 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr,
/* Make sure the device was added through sysfs */
res = -ENOENT;
i2c_lock_adapter(adap);
mutex_lock(&adap->userspace_clients_lock);
list_for_each_entry_safe(client, next, &adap->userspace_clients,
detected) {
if (client->addr == addr) {
@ -687,7 +765,7 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr,
break;
}
}
i2c_unlock_adapter(adap);
mutex_unlock(&adap->userspace_clients_lock);
if (res < 0)
dev_err(dev, "%s: Can't find device in list\n",
@ -714,10 +792,11 @@ static const struct attribute_group *i2c_adapter_attr_groups[] = {
NULL
};
static struct device_type i2c_adapter_type = {
struct device_type i2c_adapter_type = {
.groups = i2c_adapter_attr_groups,
.release = i2c_adapter_dev_release,
};
EXPORT_SYMBOL_GPL(i2c_adapter_type);
#ifdef CONFIG_I2C_COMPAT
static struct class_compat *i2c_adapter_compat_class;
@ -760,7 +839,7 @@ static int __process_new_adapter(struct device_driver *d, void *data)
static int i2c_register_adapter(struct i2c_adapter *adap)
{
int res = 0, dummy;
int res = 0;
/* Can't register until after driver model init */
if (unlikely(WARN_ON(!i2c_bus_type.p))) {
@ -769,6 +848,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
}
rt_mutex_init(&adap->bus_lock);
mutex_init(&adap->userspace_clients_lock);
INIT_LIST_HEAD(&adap->userspace_clients);
/* Set default timeout to 1 second if not already set */
@ -801,8 +881,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
/* Notify drivers */
mutex_lock(&core_lock);
dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap,
__process_new_adapter);
bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter);
mutex_unlock(&core_lock);
return 0;
@ -975,7 +1054,7 @@ int i2c_del_adapter(struct i2c_adapter *adap)
return res;
/* Remove devices instantiated from sysfs */
i2c_lock_adapter(adap);
mutex_lock(&adap->userspace_clients_lock);
list_for_each_entry_safe(client, next, &adap->userspace_clients,
detected) {
dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name,
@ -983,7 +1062,7 @@ int i2c_del_adapter(struct i2c_adapter *adap)
list_del(&client->detected);
i2c_unregister_device(client);
}
i2c_unlock_adapter(adap);
mutex_unlock(&adap->userspace_clients_lock);
/* Detach any active clients. This can't fail, thus we do not
checking the returned value. */
@ -1238,12 +1317,12 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
#endif
if (in_atomic() || irqs_disabled()) {
ret = rt_mutex_trylock(&adap->bus_lock);
ret = i2c_trylock_adapter(adap);
if (!ret)
/* I2C activity is ongoing. */
return -EAGAIN;
} else {
rt_mutex_lock(&adap->bus_lock);
i2c_lock_adapter(adap);
}
/* Retry automatically on arbitration loss */
@ -1255,7 +1334,7 @@ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
if (time_after(jiffies, orig_jiffies + adap->timeout))
break;
}
rt_mutex_unlock(&adap->bus_lock);
i2c_unlock_adapter(adap);
return ret;
} else {
@ -1350,13 +1429,17 @@ static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr)
I2C_SMBUS_BYTE_DATA, &dummy);
else
#endif
if ((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50
|| !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
I2C_SMBUS_BYTE, &dummy);
else
if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50)
&& i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK))
err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0,
I2C_SMBUS_QUICK, NULL);
else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE))
err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
I2C_SMBUS_BYTE, &dummy);
else {
dev_warn(&adap->dev, "No suitable probing method supported\n");
err = -EOPNOTSUPP;
}
return err >= 0;
}
@ -1437,16 +1520,6 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
if (!(adapter->class & driver->class))
goto exit_free;
/* Stop here if the bus doesn't support probing */
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE)) {
if (address_list[0] == I2C_CLIENT_END)
goto exit_free;
dev_warn(&adapter->dev, "Probing not supported\n");
err = -EOPNOTSUPP;
goto exit_free;
}
for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) {
dev_dbg(&adapter->dev, "found normal entry for adapter %d, "
"addr 0x%02x\n", adap_id, address_list[i]);
@ -1461,18 +1534,23 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
return err;
}
int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr)
{
return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0,
I2C_SMBUS_QUICK, NULL) >= 0;
}
EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read);
struct i2c_client *
i2c_new_probed_device(struct i2c_adapter *adap,
struct i2c_board_info *info,
unsigned short const *addr_list)
unsigned short const *addr_list,
int (*probe)(struct i2c_adapter *, unsigned short addr))
{
int i;
/* Stop here if the bus doesn't support probing */
if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) {
dev_err(&adap->dev, "Probing not supported\n");
return NULL;
}
if (!probe)
probe = i2c_default_probe;
for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) {
/* Check address validity */
@ -1490,7 +1568,7 @@ i2c_new_probed_device(struct i2c_adapter *adap,
}
/* Test address responsiveness */
if (i2c_default_probe(adap, addr_list[i]))
if (probe(adap, addr_list[i]))
break;
}
@ -2002,7 +2080,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
flags &= I2C_M_TEN | I2C_CLIENT_PEC;
if (adapter->algo->smbus_xfer) {
rt_mutex_lock(&adapter->bus_lock);
i2c_lock_adapter(adapter);
/* Retry automatically on arbitration loss */
orig_jiffies = jiffies;
@ -2016,7 +2094,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
orig_jiffies + adapter->timeout))
break;
}
rt_mutex_unlock(&adapter->bus_lock);
i2c_unlock_adapter(adapter);
} else
res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
command, protocol, data);

66
drivers/i2c/i2c-dev.c
View file

@ -167,13 +167,9 @@ static ssize_t i2cdev_write(struct file *file, const char __user *buf,
if (count > 8192)
count = 8192;
tmp = kmalloc(count, GFP_KERNEL);
if (tmp == NULL)
return -ENOMEM;
if (copy_from_user(tmp, buf, count)) {
kfree(tmp);
return -EFAULT;
}
tmp = memdup_user(buf, count);
if (IS_ERR(tmp))
return PTR_ERR(tmp);
pr_debug("i2c-dev: i2c-%d writing %zu bytes.\n",
iminor(file->f_path.dentry->d_inode), count);
@ -193,12 +189,50 @@ static int i2cdev_check(struct device *dev, void *addrp)
return dev->driver ? -EBUSY : 0;
}
/* walk up mux tree */
static int i2cdev_check_mux_parents(struct i2c_adapter *adapter, int addr)
{
int result;
result = device_for_each_child(&adapter->dev, &addr, i2cdev_check);
if (!result && i2c_parent_is_i2c_adapter(adapter))
result = i2cdev_check_mux_parents(
to_i2c_adapter(adapter->dev.parent), addr);
return result;
}
/* recurse down mux tree */
static int i2cdev_check_mux_children(struct device *dev, void *addrp)
{
int result;
if (dev->type == &i2c_adapter_type)
result = device_for_each_child(dev, addrp,
i2cdev_check_mux_children);
else
result = i2cdev_check(dev, addrp);
return result;
}
/* This address checking function differs from the one in i2c-core
in that it considers an address with a registered device, but no
driver bound to it, as NOT busy. */
static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr)
{
return device_for_each_child(&adapter->dev, &addr, i2cdev_check);
int result = 0;
if (i2c_parent_is_i2c_adapter(adapter))
result = i2cdev_check_mux_parents(
to_i2c_adapter(adapter->dev.parent), addr);
if (!result)
result = device_for_each_child(&adapter->dev, &addr,
i2cdev_check_mux_children);
return result;
}
static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
@ -219,9 +253,7 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS)
return -EINVAL;
rdwr_pa = (struct i2c_msg *)
kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg),
GFP_KERNEL);
rdwr_pa = kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg), GFP_KERNEL);
if (!rdwr_pa)
return -ENOMEM;
@ -247,15 +279,9 @@ static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client,
break;
}
data_ptrs[i] = (u8 __user *)rdwr_pa[i].buf;
rdwr_pa[i].buf = kmalloc(rdwr_pa[i].len, GFP_KERNEL);
if (rdwr_pa[i].buf == NULL) {
res = -ENOMEM;
break;
}
if (copy_from_user(rdwr_pa[i].buf, data_ptrs[i],
rdwr_pa[i].len)) {
++i; /* Needs to be kfreed too */
res = -EFAULT;
rdwr_pa[i].buf = memdup_user(data_ptrs[i], rdwr_pa[i].len);
if (IS_ERR(rdwr_pa[i].buf)) {
res = PTR_ERR(rdwr_pa[i].buf);
break;
}
}

165
drivers/i2c/i2c-mux.c Normal file
View file

@ -0,0 +1,165 @@
/*
* Multiplexed I2C bus driver.
*
* Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
* Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
* Copyright (c) 2009-2010 NSN GmbH & Co KG <michael.lawnick.ext@nsn.com>
*
* Simplifies access to complex multiplexed I2C bus topologies, by presenting
* each multiplexed bus segment as an additional I2C adapter.
* Supports multi-level mux'ing (mux behind a mux).
*
* Based on:
* i2c-virt.c from Kumar Gala <galak@kernel.crashing.org>
* i2c-virtual.c from Ken Harrenstien, Copyright (c) 2004 Google, Inc.
* i2c-virtual.c from Brian Kuschak <bkuschak@yahoo.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
/* multiplexer per channel data */
struct i2c_mux_priv {
struct i2c_adapter adap;
struct i2c_algorithm algo;
struct i2c_adapter *parent;
void *mux_dev; /* the mux chip/device */
u32 chan_id; /* the channel id */
int (*select)(struct i2c_adapter *, void *mux_dev, u32 chan_id);
int (*deselect)(struct i2c_adapter *, void *mux_dev, u32 chan_id);
};
static int i2c_mux_master_xfer(struct i2c_adapter *adap,
struct i2c_msg msgs[], int num)
{
struct i2c_mux_priv *priv = adap->algo_data;
struct i2c_adapter *parent = priv->parent;
int ret;
/* Switch to the right mux port and perform the transfer. */
ret = priv->select(parent, priv->mux_dev, priv->chan_id);
if (ret >= 0)
ret = parent->algo->master_xfer(parent, msgs, num);
if (priv->deselect)
priv->deselect(parent, priv->mux_dev, priv->chan_id);
return ret;
}
static int i2c_mux_smbus_xfer(struct i2c_adapter *adap,
u16 addr, unsigned short flags,
char read_write, u8 command,
int size, union i2c_smbus_data *data)
{
struct i2c_mux_priv *priv = adap->algo_data;
struct i2c_adapter *parent = priv->parent;
int ret;
/* Select the right mux port and perform the transfer. */
ret = priv->select(parent, priv->mux_dev, priv->chan_id);
if (ret >= 0)
ret = parent->algo->smbus_xfer(parent, addr, flags,
read_write, command, size, data);
if (priv->deselect)
priv->deselect(parent, priv->mux_dev, priv->chan_id);
return ret;
}
/* Return the parent's functionality */
static u32 i2c_mux_functionality(struct i2c_adapter *adap)
{
struct i2c_mux_priv *priv = adap->algo_data;
struct i2c_adapter *parent = priv->parent;
return parent->algo->functionality(parent);
}
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
void *mux_dev, u32 force_nr, u32 chan_id,
int (*select) (struct i2c_adapter *,
void *, u32),
int (*deselect) (struct i2c_adapter *,
void *, u32))
{
struct i2c_mux_priv *priv;
int ret;
priv = kzalloc(sizeof(struct i2c_mux_priv), GFP_KERNEL);
if (!priv)
return NULL;
/* Set up private adapter data */
priv->parent = parent;
priv->mux_dev = mux_dev;
priv->chan_id = chan_id;
priv->select = select;
priv->deselect = deselect;
/* Need to do algo dynamically because we don't know ahead
* of time what sort of physical adapter we'll be dealing with.
*/
if (parent->algo->master_xfer)
priv->algo.master_xfer = i2c_mux_master_xfer;
if (parent->algo->smbus_xfer)
priv->algo.smbus_xfer = i2c_mux_smbus_xfer;
priv->algo.functionality = i2c_mux_functionality;
/* Now fill out new adapter structure */
snprintf(priv->adap.name, sizeof(priv->adap.name),
"i2c-%d-mux (chan_id %d)", i2c_adapter_id(parent), chan_id);
priv->adap.owner = THIS_MODULE;
priv->adap.id = parent->id;
priv->adap.algo = &priv->algo;
priv->adap.algo_data = priv;
priv->adap.dev.parent = &parent->dev;
if (force_nr) {
priv->adap.nr = force_nr;
ret = i2c_add_numbered_adapter(&priv->adap);
} else {
ret = i2c_add_adapter(&priv->adap);
}
if (ret < 0) {
dev_err(&parent->dev,
"failed to add mux-adapter (error=%d)\n",
ret);
kfree(priv);
return NULL;
}
dev_info(&parent->dev, "Added multiplexed i2c bus %d\n",
i2c_adapter_id(&priv->adap));
return &priv->adap;
}
EXPORT_SYMBOL_GPL(i2c_add_mux_adapter);
int i2c_del_mux_adapter(struct i2c_adapter *adap)
{
struct i2c_mux_priv *priv = adap->algo_data;
int ret;
ret = i2c_del_adapter(adap);
if (ret < 0)
return ret;
kfree(priv);
return 0;
}
EXPORT_SYMBOL_GPL(i2c_del_mux_adapter);
MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
MODULE_DESCRIPTION("I2C driver for multiplexed I2C busses");
MODULE_LICENSE("GPL v2");

18
drivers/i2c/muxes/Kconfig Normal file
View file

@ -0,0 +1,18 @@
#
# Multiplexer I2C chip drivers configuration
#
menu "Multiplexer I2C Chip support"
depends on I2C_MUX
config I2C_MUX_PCA954x
tristate "Philips PCA954x I2C Mux/switches"
depends on EXPERIMENTAL
help
If you say yes here you get support for the Philips PCA954x
I2C mux/switch devices.
This driver can also be built as a module. If so, the module
will be called pca954x.
endmenu

8
drivers/i2c/muxes/Makefile Normal file
View file

@ -0,0 +1,8 @@
#
# Makefile for multiplexer I2C chip drivers.
obj-$(CONFIG_I2C_MUX_PCA954x) += pca954x.o
ifeq ($(CONFIG_I2C_DEBUG_BUS),y)
EXTRA_CFLAGS += -DDEBUG
endif

301
drivers/i2c/muxes/pca954x.c Normal file
View file

@ -0,0 +1,301 @@
/*
* I2C multiplexer
*
* Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
* Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
*
* This module supports the PCA954x series of I2C multiplexer/switch chips
* made by Philips Semiconductors.
* This includes the:
* PCA9540, PCA9542, PCA9543, PCA9544, PCA9545, PCA9546, PCA9547
* and PCA9548.
*
* These chips are all controlled via the I2C bus itself, and all have a
* single 8-bit register. The upstream "parent" bus fans out to two,
* four, or eight downstream busses or channels; which of these
* are selected is determined by the chip type and register contents. A
* mux can select only one sub-bus at a time; a switch can select any
* combination simultaneously.
*
* Based on:
* pca954x.c from Kumar Gala <galak@kernel.crashing.org>
* Copyright (C) 2006
*
* Based on:
* pca954x.c from Ken Harrenstien
* Copyright (C) 2004 Google, Inc. (Ken Harrenstien)
*
* Based on:
* i2c-virtual_cb.c from Brian Kuschak <bkuschak@yahoo.com>
* and
* pca9540.c from Jean Delvare <khali@linux-fr.org>.
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/i2c-mux.h>
#include <linux/i2c/pca954x.h>
#define PCA954X_MAX_NCHANS 8
enum pca_type {
pca_9540,
pca_9542,
pca_9543,
pca_9544,
pca_9545,
pca_9546,
pca_9547,
pca_9548,
};
struct pca954x {
enum pca_type type;
struct i2c_adapter *virt_adaps[PCA954X_MAX_NCHANS];
u8 last_chan; /* last register value */
};
struct chip_desc {
u8 nchans;
u8 enable; /* used for muxes only */
enum muxtype {
pca954x_ismux = 0,
pca954x_isswi
} muxtype;
};
/* Provide specs for the PCA954x types we know about */
static const struct chip_desc chips[] = {
[pca_9540] = {
.nchans = 2,
.enable = 0x4,
.muxtype = pca954x_ismux,
},
[pca_9543] = {
.nchans = 2,
.muxtype = pca954x_isswi,
},
[pca_9544] = {
.nchans = 4,
.enable = 0x4,
.muxtype = pca954x_ismux,
},
[pca_9545] = {
.nchans = 4,
.muxtype = pca954x_isswi,
},
[pca_9547] = {
.nchans = 8,
.enable = 0x8,
.muxtype = pca954x_ismux,
},
[pca_9548] = {
.nchans = 8,
.muxtype = pca954x_isswi,
},
};
static const struct i2c_device_id pca954x_id[] = {
{ "pca9540", pca_9540 },
{ "pca9542", pca_9540 },
{ "pca9543", pca_9543 },
{ "pca9544", pca_9544 },
{ "pca9545", pca_9545 },
{ "pca9546", pca_9545 },
{ "pca9547", pca_9547 },
{ "pca9548", pca_9548 },
{ }
};
MODULE_DEVICE_TABLE(i2c, pca954x_id);
/* Write to mux register. Don't use i2c_transfer()/i2c_smbus_xfer()
for this as they will try to lock adapter a second time */
static int pca954x_reg_write(struct i2c_adapter *adap,
struct i2c_client *client, u8 val)
{
int ret = -ENODEV;
if (adap->algo->master_xfer) {
struct i2c_msg msg;
char buf[1];
msg.addr = client->addr;
msg.flags = 0;
msg.len = 1;
buf[0] = val;
msg.buf = buf;
ret = adap->algo->master_xfer(adap, &msg, 1);
} else {
union i2c_smbus_data data;
ret = adap->algo->smbus_xfer(adap, client->addr,
client->flags,
I2C_SMBUS_WRITE,
val, I2C_SMBUS_BYTE, &data);
}
return ret;
}
static int pca954x_select_chan(struct i2c_adapter *adap,
void *client, u32 chan)
{
struct pca954x *data = i2c_get_clientdata(client);
const struct chip_desc *chip = &chips[data->type];
u8 regval;
int ret = 0;
/* we make switches look like muxes, not sure how to be smarter */
if (chip->muxtype == pca954x_ismux)
regval = chan | chip->enable;
else
regval = 1 << chan;
/* Only select the channel if its different from the last channel */
if (data->last_chan != regval) {
ret = pca954x_reg_write(adap, client, regval);
data->last_chan = regval;
}
return ret;
}
static int pca954x_deselect_mux(struct i2c_adapter *adap,
void *client, u32 chan)
{
struct pca954x *data = i2c_get_clientdata(client);
/* Deselect active channel */
data->last_chan = 0;
return pca954x_reg_write(adap, client, data->last_chan);
}
/*
* I2C init/probing/exit functions
*/
static int __devinit pca954x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct i2c_adapter *adap = to_i2c_adapter(client->dev.parent);
struct pca954x_platform_data *pdata = client->dev.platform_data;
int num, force;
struct pca954x *data;
int ret = -ENODEV;
if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_BYTE))
goto err;
data = kzalloc(sizeof(struct pca954x), GFP_KERNEL);
if (!data) {
ret = -ENOMEM;
goto err;
}
i2c_set_clientdata(client, data);
/* Read the mux register at addr to verify
* that the mux is in fact present.
*/
if (i2c_smbus_read_byte(client) < 0) {
dev_warn(&client->dev, "probe failed\n");
goto exit_free;
}
data->type = id->driver_data;
data->last_chan = 0; /* force the first selection */
/* Now create an adapter for each channel */
for (num = 0; num < chips[data->type].nchans; num++) {
force = 0; /* dynamic adap number */
if (pdata) {
if (num < pdata->num_modes)
/* force static number */
force = pdata->modes[num].adap_id;
else
/* discard unconfigured channels */
break;
}
data->virt_adaps[num] =
i2c_add_mux_adapter(adap, client,
force, num, pca954x_select_chan,
(pdata && pdata->modes[num].deselect_on_exit)
? pca954x_deselect_mux : NULL);
if (data->virt_adaps[num] == NULL) {
ret = -ENODEV;
dev_err(&client->dev,
"failed to register multiplexed adapter"
" %d as bus %d\n", num, force);
goto virt_reg_failed;
}
}
dev_info(&client->dev,
"registered %d multiplexed busses for I2C %s %s\n",
num, chips[data->type].muxtype == pca954x_ismux
? "mux" : "switch", client->name);
return 0;
virt_reg_failed:
for (num--; num >= 0; num--)
i2c_del_mux_adapter(data->virt_adaps[num]);
exit_free:
kfree(data);
err:
return ret;
}
static int __devexit pca954x_remove(struct i2c_client *client)
{
struct pca954x *data = i2c_get_clientdata(client);
const struct chip_desc *chip = &chips[data->type];
int i, err;
for (i = 0; i < chip->nchans; ++i)
if (data->virt_adaps[i]) {
err = i2c_del_mux_adapter(data->virt_adaps[i]);
if (err)
return err;
data->virt_adaps[i] = NULL;
}
kfree(data);
return 0;
}
static struct i2c_driver pca954x_driver = {
.driver = {
.name = "pca954x",
.owner = THIS_MODULE,
},
.probe = pca954x_probe,
.remove = __devexit_p(pca954x_remove),
.id_table = pca954x_id,
};
static int __init pca954x_init(void)
{
return i2c_add_driver(&pca954x_driver);
}
static void __exit pca954x_exit(void)
{
i2c_del_driver(&pca954x_driver);
}
module_init(pca954x_init);
module_exit(pca954x_exit);
MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
MODULE_DESCRIPTION("PCA954x I2C mux/switch driver");
MODULE_LICENSE("GPL v2");

4
drivers/macintosh/therm_windtunnel.c
View file

@ -322,10 +322,10 @@ do_attach( struct i2c_adapter *adapter )
memset(&info, 0, sizeof(struct i2c_board_info));
strlcpy(info.type, "therm_ds1775", I2C_NAME_SIZE);
i2c_new_probed_device(adapter, &info, scan_ds1775);
i2c_new_probed_device(adapter, &info, scan_ds1775, NULL);
strlcpy(info.type, "therm_adm1030", I2C_NAME_SIZE);
i2c_new_probed_device(adapter, &info, scan_adm1030);
i2c_new_probed_device(adapter, &info, scan_adm1030, NULL);
if( x.thermostat && x.fan ) {
x.running = 1;

2
drivers/media/video/bt8xx/bttv-i2c.c
View file

@ -411,7 +411,7 @@ void __devinit init_bttv_i2c_ir(struct bttv *btv)
memset(&info, 0, sizeof(struct i2c_board_info));
strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
i2c_new_probed_device(&btv->c.i2c_adap, &info, addr_list);
i2c_new_probed_device(&btv->c.i2c_adap, &info, addr_list, NULL);
}
}

3
drivers/media/video/cx18/cx18-i2c.c
View file

@ -117,7 +117,8 @@ static int cx18_i2c_new_ir(struct cx18 *cx, struct i2c_adapter *adap, u32 hw,
break;
}
return i2c_new_probed_device(adap, &info, addr_list) == NULL ? -1 : 0;
return i2c_new_probed_device(adap, &info, addr_list, NULL) == NULL ?
-1 : 0;
}
int cx18_i2c_register(struct cx18 *cx, unsigned idx)

15
drivers/media/video/cx23885/cx23885-i2c.c
View file

@ -364,17 +364,10 @@ int cx23885_i2c_register(struct cx23885_i2c *bus)
memset(&info, 0, sizeof(struct i2c_board_info));
strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
/*
* We can't call i2c_new_probed_device() because it uses
* quick writes for probing and the IR receiver device only
* replies to reads.
*/
if (i2c_smbus_xfer(&bus->i2c_adap, addr_list[0], 0,
I2C_SMBUS_READ, 0, I2C_SMBUS_QUICK,
NULL) >= 0) {
info.addr = addr_list[0];
i2c_new_device(&bus->i2c_adap, &info);
}
/* Use quick read command for probe, some IR chips don't
* support writes */
i2c_new_probed_device(&bus->i2c_adap, &info, addr_list,
i2c_probe_func_quick_read);
}
return bus->i2c_rc;

19
drivers/media/video/cx88/cx88-i2c.c
View file

@ -193,24 +193,13 @@ void cx88_i2c_init_ir(struct cx88_core *core)
0x18, 0x6b, 0x71,
I2C_CLIENT_END
};
const unsigned short *addrp;
memset(&info, 0, sizeof(struct i2c_board_info));
strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
/*
* We can't call i2c_new_probed_device() because it uses
* quick writes for probing and at least some R receiver
* devices only reply to reads.
*/
for (addrp = addr_list; *addrp != I2C_CLIENT_END; addrp++) {
if (i2c_smbus_xfer(&core->i2c_adap, *addrp, 0,
I2C_SMBUS_READ, 0,
I2C_SMBUS_QUICK, NULL) >= 0) {
info.addr = *addrp;
i2c_new_device(&core->i2c_adap, &info);
break;
}
}
/* Use quick read command for probe, some IR chips don't
* support writes */
i2c_new_probed_device(&core->i2c_adap, &info, addr_list,
i2c_probe_func_quick_read);
}
}

2
drivers/media/video/em28xx/em28xx-cards.c
View file

@ -2385,7 +2385,7 @@ void em28xx_register_i2c_ir(struct em28xx *dev)
if (dev->init_data.name)
info.platform_data = &dev->init_data;
i2c_new_probed_device(&dev->i2c_adap, &info, addr_list);
i2c_new_probed_device(&dev->i2c_adap, &info, addr_list, NULL);
}
void em28xx_card_setup(struct em28xx *dev)

9
drivers/media/video/ivtv/ivtv-i2c.c
View file

@ -183,8 +183,8 @@ static int ivtv_i2c_new_ir(struct ivtv *itv, u32 hw, const char *type, u8 addr)
return -1;
memset(&info, 0, sizeof(struct i2c_board_info));
strlcpy(info.type, type, I2C_NAME_SIZE);
return i2c_new_probed_device(adap, &info, addr_list) == NULL
? -1 : 0;
return i2c_new_probed_device(adap, &info, addr_list, NULL)
== NULL ? -1 : 0;
}
/* Only allow one IR receiver to be registered per board */
@ -221,7 +221,8 @@ static int ivtv_i2c_new_ir(struct ivtv *itv, u32 hw, const char *type, u8 addr)
info.platform_data = init_data;
strlcpy(info.type, type, I2C_NAME_SIZE);
return i2c_new_probed_device(adap, &info, addr_list) == NULL ? -1 : 0;
return i2c_new_probed_device(adap, &info, addr_list, NULL) == NULL ?
-1 : 0;
}
/* Instantiate the IR receiver device using probing -- undesirable */
@ -249,7 +250,7 @@ struct i2c_client *ivtv_i2c_new_ir_legacy(struct ivtv *itv)
memset(&info, 0, sizeof(struct i2c_board_info));
strlcpy(info.type, "ir_video", I2C_NAME_SIZE);
return i2c_new_probed_device(&itv->i2c_adap, &info, addr_list);
return i2c_new_probed_device(&itv->i2c_adap, &info, addr_list, NULL);
}
int ivtv_i2c_register(struct ivtv *itv, unsigned idx)

3
drivers/media/video/v4l2-common.c
View file

@ -381,7 +381,8 @@ struct v4l2_subdev *v4l2_i2c_new_subdev_board(struct v4l2_device *v4l2_dev,
/* Create the i2c client */
if (info->addr == 0 && probe_addrs)
client = i2c_new_probed_device(adapter, info, probe_addrs);
client = i2c_new_probed_device(adapter, info, probe_addrs,
NULL);
else
client = i2c_new_device(adapter, info);

2
drivers/usb/host/ohci-pnx4008.c
View file

@ -329,7 +329,7 @@ static int __devinit usb_hcd_pnx4008_probe(struct platform_device *pdev)
memset(&i2c_info, 0, sizeof(struct i2c_board_info));
strlcpy(i2c_info.type, "isp1301_pnx", I2C_NAME_SIZE);
isp1301_i2c_client = i2c_new_probed_device(i2c_adap, &i2c_info,
normal_i2c);
normal_i2c, NULL);
i2c_put_adapter(i2c_adap);
if (!isp1301_i2c_client) {
err("failed to connect I2C to ISP1301 USB Transceiver");

2
drivers/video/matrox/i2c-matroxfb.c
View file

@ -191,7 +191,7 @@ static void* i2c_matroxfb_probe(struct matrox_fb_info* minfo) {
};
i2c_new_probed_device(&m2info->maven.adapter,
&maven_info, addr_list);
&maven_info, addr_list, NULL);
}
}
return m2info;

46
include/linux/i2c-mux.h Normal file
View file

@ -0,0 +1,46 @@
/*
*
* i2c-mux.h - functions for the i2c-bus mux support
*
* Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
* Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
* Michael Lawnick <michael.lawnick.ext@nsn.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.
*/
#ifndef _LINUX_I2C_MUX_H
#define _LINUX_I2C_MUX_H
#ifdef __KERNEL__
/*
* Called to create a i2c bus on a multiplexed bus segment.
* The mux_dev and chan_id parameters are passed to the select
* and deselect callback functions to perform hardware-specific
* mux control.
*/
struct i2c_adapter *i2c_add_mux_adapter(struct i2c_adapter *parent,
void *mux_dev, u32 force_nr, u32 chan_id,
int (*select) (struct i2c_adapter *,
void *mux_dev, u32 chan_id),
int (*deselect) (struct i2c_adapter *,
void *mux_dev, u32 chan_id));
int i2c_del_mux_adapter(struct i2c_adapter *adap);
#endif /* __KERNEL__ */
#endif /* _LINUX_I2C_MUX_H */

33
include/linux/i2c.h
View file

@ -37,6 +37,7 @@
#include <linux/of.h> /* for struct device_node */
extern struct bus_type i2c_bus_type;
extern struct device_type i2c_adapter_type;
/* --- General options ------------------------------------------------ */
@ -284,12 +285,18 @@ i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info);
/* If you don't know the exact address of an I2C device, use this variant
* instead, which can probe for device presence in a list of possible
* addresses.
* addresses. The "probe" callback function is optional. If it is provided,
* it must return 1 on successful probe, 0 otherwise. If it is not provided,
* a default probing method is used.
*/
extern struct i2c_client *
i2c_new_probed_device(struct i2c_adapter *adap,
struct i2c_board_info *info,
unsigned short const *addr_list);
unsigned short const *addr_list,
int (*probe)(struct i2c_adapter *, unsigned short addr));
/* Common custom probe functions */
extern int i2c_probe_func_quick_read(struct i2c_adapter *, unsigned short addr);
/* For devices that use several addresses, use i2c_new_dummy() to make
* client handles for the extra addresses.
@ -362,6 +369,7 @@ struct i2c_adapter {
char name[48];
struct completion dev_released;
struct mutex userspace_clients_lock;
struct list_head userspace_clients;
};
#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
@ -376,23 +384,16 @@ static inline void i2c_set_adapdata(struct i2c_adapter *dev, void *data)
dev_set_drvdata(&dev->dev, data);
}
/**
* i2c_lock_adapter - Prevent access to an I2C bus segment
* @adapter: Target I2C bus segment
*/
static inline void i2c_lock_adapter(struct i2c_adapter *adapter)
static inline int i2c_parent_is_i2c_adapter(const struct i2c_adapter *adapter)
{
rt_mutex_lock(&adapter->bus_lock);
return adapter->dev.parent != NULL
&& adapter->dev.parent->bus == &i2c_bus_type
&& adapter->dev.parent->type == &i2c_adapter_type;
}
/**
* i2c_unlock_adapter - Reauthorize access to an I2C bus segment
* @adapter: Target I2C bus segment
*/
static inline void i2c_unlock_adapter(struct i2c_adapter *adapter)
{
rt_mutex_unlock(&adapter->bus_lock);
}
/* Adapter locking functions, exported for shared pin cases */
void i2c_lock_adapter(struct i2c_adapter *);
void i2c_unlock_adapter(struct i2c_adapter *);
/*flags for the client struct: */
#define I2C_CLIENT_PEC 0x04 /* Use Packet Error Checking */

47
include/linux/i2c/pca954x.h Normal file
View file

@ -0,0 +1,47 @@
/*
*
* pca954x.h - I2C multiplexer/switch support
*
* Copyright (c) 2008-2009 Rodolfo Giometti <giometti@linux.it>
* Copyright (c) 2008-2009 Eurotech S.p.A. <info@eurotech.it>
* Michael Lawnick <michael.lawnick.ext@nsn.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.
*/
#ifndef _LINUX_I2C_PCA954X_H
#define _LINUX_I2C_PCA954X_H
/* Platform data for the PCA954x I2C multiplexers */
/* Per channel initialisation data:
* @adap_id: bus number for the adapter. 0 = don't care
* @deselect_on_exit: set this entry to 1, if your H/W needs deselection
* of this channel after transaction.
*
*/
struct pca954x_platform_mode {
int adap_id;
unsigned int deselect_on_exit:1;
};
/* Per mux/switch data, used with i2c_register_board_info */
struct pca954x_platform_data {
struct pca954x_platform_mode *modes;
int num_modes;
};
#endif /* _LINUX_I2C_PCA954X_H */