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-rw-r--r--drivers/i2c/busses/i2c-pasemi.c7
-rw-r--r--drivers/i2c/chips/eeprom.c37
-rw-r--r--drivers/i2c/i2c-core.c3
-rw-r--r--drivers/i2c/i2c-dev.c86
-rw-r--r--include/linux/i2c.h5
5 files changed, 115 insertions, 23 deletions
diff --git a/drivers/i2c/busses/i2c-pasemi.c b/drivers/i2c/busses/i2c-pasemi.c
index 58e3271..ca18e0b 100644
--- a/drivers/i2c/busses/i2c-pasemi.c
+++ b/drivers/i2c/busses/i2c-pasemi.c
@@ -51,6 +51,7 @@ struct pasemi_smbus {
#define MRXFIFO_DATA_M 0x000000ff
#define SMSTA_XEN 0x08000000
+#define SMSTA_MTN 0x00200000
#define CTL_MRR 0x00000400
#define CTL_MTR 0x00000200
@@ -98,6 +99,10 @@ static unsigned int pasemi_smb_waitready(struct pasemi_smbus *smbus)
status = reg_read(smbus, REG_SMSTA);
}
+ /* Got NACK? */
+ if (status & SMSTA_MTN)
+ return -ENXIO;
+
if (timeout < 0) {
dev_warn(&smbus->dev->dev, "Timeout, status 0x%08x\n", status);
reg_write(smbus, REG_SMSTA, status);
@@ -364,7 +369,7 @@ static int __devinit pasemi_smb_probe(struct pci_dev *dev,
smbus->adapter.algo = &smbus_algorithm;
smbus->adapter.algo_data = smbus;
- /* set up the driverfs linkage to our parent device */
+ /* set up the sysfs linkage to our parent device */
smbus->adapter.dev.parent = &dev->dev;
reg_write(smbus, REG_CTL, (CTL_MTR | CTL_MRR |
diff --git a/drivers/i2c/chips/eeprom.c b/drivers/i2c/chips/eeprom.c
index d3da1fb..1a7eeeb 100644
--- a/drivers/i2c/chips/eeprom.c
+++ b/drivers/i2c/chips/eeprom.c
@@ -128,13 +128,20 @@ static ssize_t eeprom_read(struct kobject *kobj, struct bin_attribute *bin_attr,
for (slice = off >> 5; slice <= (off + count - 1) >> 5; slice++)
eeprom_update_client(client, slice);
- /* Hide Vaio security settings to regular users (16 first bytes) */
- if (data->nature == VAIO && off < 16 && !capable(CAP_SYS_ADMIN)) {
- size_t in_row1 = 16 - off;
- in_row1 = min(in_row1, count);
- memset(buf, 0, in_row1);
- if (count - in_row1 > 0)
- memcpy(buf + in_row1, &data->data[16], count - in_row1);
+ /* Hide Vaio private settings to regular users:
+ - BIOS passwords: bytes 0x00 to 0x0f
+ - UUID: bytes 0x10 to 0x1f
+ - Serial number: 0xc0 to 0xdf */
+ if (data->nature == VAIO && !capable(CAP_SYS_ADMIN)) {
+ int i;
+
+ for (i = 0; i < count; i++) {
+ if ((off + i <= 0x1f) ||
+ (off + i >= 0xc0 && off + i <= 0xdf))
+ buf[i] = 0;
+ else
+ buf[i] = data->data[off + i];
+ }
} else {
memcpy(buf, &data->data[off], count);
}
@@ -197,14 +204,18 @@ static int eeprom_detect(struct i2c_adapter *adapter, int address, int kind)
goto exit_kfree;
/* Detect the Vaio nature of EEPROMs.
- We use the "PCG-" prefix as the signature. */
+ We use the "PCG-" or "VGN-" prefix as the signature. */
if (address == 0x57) {
- if (i2c_smbus_read_byte_data(new_client, 0x80) == 'P'
- && i2c_smbus_read_byte(new_client) == 'C'
- && i2c_smbus_read_byte(new_client) == 'G'
- && i2c_smbus_read_byte(new_client) == '-') {
+ char name[4];
+
+ name[0] = i2c_smbus_read_byte_data(new_client, 0x80);
+ name[1] = i2c_smbus_read_byte(new_client);
+ name[2] = i2c_smbus_read_byte(new_client);
+ name[3] = i2c_smbus_read_byte(new_client);
+
+ if (!memcmp(name, "PCG-", 4) || !memcmp(name, "VGN-", 4)) {
dev_info(&new_client->dev, "Vaio EEPROM detected, "
- "enabling password protection\n");
+ "enabling privacy protection\n");
data->nature = VAIO;
}
}
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 1a4e8dc..b5e13e4 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -673,7 +673,7 @@ static int __i2c_check_addr(struct i2c_adapter *adapter, unsigned int addr)
return 0;
}
-int i2c_check_addr(struct i2c_adapter *adapter, int addr)
+static int i2c_check_addr(struct i2c_adapter *adapter, int addr)
{
int rval;
@@ -683,7 +683,6 @@ int i2c_check_addr(struct i2c_adapter *adapter, int addr)
return rval;
}
-EXPORT_SYMBOL(i2c_check_addr);
int i2c_attach_client(struct i2c_client *client)
{
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index 5a15e50..c21ae20 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -38,6 +38,15 @@
static struct i2c_driver i2cdev_driver;
+/*
+ * An i2c_dev represents an i2c_adapter ... an I2C or SMBus master, not a
+ * slave (i2c_client) with which messages will be exchanged. It's coupled
+ * with a character special file which is accessed by user mode drivers.
+ *
+ * The list of i2c_dev structures is parallel to the i2c_adapter lists
+ * maintained by the driver model, and is updated using notifications
+ * delivered to the i2cdev_driver.
+ */
struct i2c_dev {
struct list_head list;
struct i2c_adapter *adap;
@@ -103,6 +112,25 @@ static ssize_t show_adapter_name(struct device *dev,
}
static DEVICE_ATTR(name, S_IRUGO, show_adapter_name, NULL);
+/* ------------------------------------------------------------------------- */
+
+/*
+ * After opening an instance of this character special file, a file
+ * descriptor starts out associated only with an i2c_adapter (and bus).
+ *
+ * Using the I2C_RDWR ioctl(), you can then *immediately* issue i2c_msg
+ * traffic to any devices on the bus used by that adapter. That's because
+ * the i2c_msg vectors embed all the addressing information they need, and
+ * are submitted directly to an i2c_adapter. However, SMBus-only adapters
+ * don't support that interface.
+ *
+ * To use read()/write() system calls on that file descriptor, or to use
+ * SMBus interfaces (and work with SMBus-only hosts!), you must first issue
+ * an I2C_SLAVE (or I2C_SLAVE_FORCE) ioctl. That configures an anonymous
+ * (never registered) i2c_client so it holds the addressing information
+ * needed by those system calls and by this SMBus interface.
+ */
+
static ssize_t i2cdev_read (struct file *file, char __user *buf, size_t count,
loff_t *offset)
{
@@ -154,6 +182,29 @@ static ssize_t i2cdev_write (struct file *file, const char __user *buf, size_t c
return ret;
}
+/* This address checking function differs from the one in i2c-core
+ in that it considers an address with a registered device, but no
+ bounded driver, as NOT busy. */
+static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr)
+{
+ struct list_head *item;
+ struct i2c_client *client;
+ int res = 0;
+
+ mutex_lock(&adapter->clist_lock);
+ list_for_each(item, &adapter->clients) {
+ client = list_entry(item, struct i2c_client, list);
+ if (client->addr == addr) {
+ if (client->driver)
+ res = -EBUSY;
+ break;
+ }
+ }
+ mutex_unlock(&adapter->clist_lock);
+
+ return res;
+}
+
static int i2cdev_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
@@ -172,11 +223,22 @@ static int i2cdev_ioctl(struct inode *inode, struct file *file,
switch ( cmd ) {
case I2C_SLAVE:
case I2C_SLAVE_FORCE:
+ /* NOTE: devices set up to work with "new style" drivers
+ * can't use I2C_SLAVE, even when the device node is not
+ * bound to a driver. Only I2C_SLAVE_FORCE will work.
+ *
+ * Setting the PEC flag here won't affect kernel drivers,
+ * which will be using the i2c_client node registered with
+ * the driver model core. Likewise, when that client has
+ * the PEC flag already set, the i2c-dev driver won't see
+ * (or use) this setting.
+ */
if ((arg > 0x3ff) ||
(((client->flags & I2C_M_TEN) == 0) && arg > 0x7f))
return -EINVAL;
- if ((cmd == I2C_SLAVE) && i2c_check_addr(client->adapter,arg))
+ if (cmd == I2C_SLAVE && i2cdev_check_addr(client->adapter, arg))
return -EBUSY;
+ /* REVISIT: address could become busy later */
client->addr = arg;
return 0;
case I2C_TENBIT:
@@ -386,6 +448,13 @@ static int i2cdev_open(struct inode *inode, struct file *file)
if (!adap)
return -ENODEV;
+ /* This creates an anonymous i2c_client, which may later be
+ * pointed to some address using I2C_SLAVE or I2C_SLAVE_FORCE.
+ *
+ * This client is ** NEVER REGISTERED ** with the driver model
+ * or I2C core code!! It just holds private copies of addressing
+ * information and maybe a PEC flag.
+ */
client = kzalloc(sizeof(*client), GFP_KERNEL);
if (!client) {
i2c_put_adapter(adap);
@@ -394,7 +463,6 @@ static int i2cdev_open(struct inode *inode, struct file *file)
snprintf(client->name, I2C_NAME_SIZE, "i2c-dev %d", adap->nr);
client->driver = &i2cdev_driver;
- /* registered with adapter, passed as client to user */
client->adapter = adap;
file->private_data = client;
@@ -422,6 +490,14 @@ static const struct file_operations i2cdev_fops = {
.release = i2cdev_release,
};
+/* ------------------------------------------------------------------------- */
+
+/*
+ * The legacy "i2cdev_driver" is used primarily to get notifications when
+ * I2C adapters are added or removed, so that each one gets an i2c_dev
+ * and is thus made available to userspace driver code.
+ */
+
static struct class *i2c_dev_class;
static int i2cdev_attach_adapter(struct i2c_adapter *adap)
@@ -486,6 +562,12 @@ static struct i2c_driver i2cdev_driver = {
.detach_client = i2cdev_detach_client,
};
+/* ------------------------------------------------------------------------- */
+
+/*
+ * module load/unload record keeping
+ */
+
static int __init i2c_dev_init(void)
{
int res;
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 8033e6b..a100c9f 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -400,11 +400,6 @@ extern int i2c_release_client(struct i2c_client *);
extern void i2c_clients_command(struct i2c_adapter *adap,
unsigned int cmd, void *arg);
-/* returns -EBUSY if address has been taken, 0 if not. Note that the only
- other place at which this is called is within i2c_attach_client; so
- you can cheat by simply not registering. Not recommended, of course! */
-extern int i2c_check_addr (struct i2c_adapter *adapter, int addr);
-
/* Detect function. It iterates over all possible addresses itself.
* It will only call found_proc if some client is connected at the
* specific address (unless a 'force' matched);
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