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

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* 'i2c-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  i2c-nforce2: Remove redundant error messages on ACPI conflict
  i2c: Use <linux/io.h> instead of <asm/io.h>
  i2c-algo-pca: Fix coding style issues
  i2c-dev: Fix all coding style issues
  i2c-core: Fix some coding style issues
  i2c-gpio: Move initialization code to subsys_initcall()
  i2c-parport: Make template structure const
  i2c-dev: Remove unnecessary casts
  at24: Fall back to byte or word reads if needed
  i2c-stub: Expose the default functionality flags
  i2c/scx200_acb: Make PCI device ids constant
  i2c-i801: Fix all checkpatch warnings
  i2c-i801: All newer devices have all the optional features
  i2c-i801: Let the user disable selected driver features
This commit is contained in:
Linus Torvalds
2010-05-21 10:49:43 -07:00
parent 7f02ab3ce3 7c4fda1aa1
commit e0bc5d4a54
41 changed files with 216 additions and 166 deletions
Download Patch File Download Diff File Expand all files Collapse all files
drivers/misc/eeprom/at24.c
+48 -11
View File
@@ -54,7 +54,7 @@
struct at24_data {
struct at24_platform_data chip;
struct memory_accessor macc;
bool use_smbus;
int use_smbus;
/*
* Lock protects against activities from other Linux tasks,
@@ -184,11 +184,19 @@ static ssize_t at24_eeprom_read(struct at24_data *at24, char *buf,
if (count > io_limit)
count = io_limit;
if (at24->use_smbus) {
switch (at24->use_smbus) {
case I2C_SMBUS_I2C_BLOCK_DATA:
/* Smaller eeproms can work given some SMBus extension calls */
if (count > I2C_SMBUS_BLOCK_MAX)
count = I2C_SMBUS_BLOCK_MAX;
} else {
break;
case I2C_SMBUS_WORD_DATA:
count = 2;
break;
case I2C_SMBUS_BYTE_DATA:
count = 1;
break;
default:
/*
* When we have a better choice than SMBus calls, use a
* combined I2C message. Write address; then read up to
@@ -219,10 +227,27 @@ static ssize_t at24_eeprom_read(struct at24_data *at24, char *buf,
timeout = jiffies + msecs_to_jiffies(write_timeout);
do {
read_time = jiffies;
if (at24->use_smbus) {
switch (at24->use_smbus) {
case I2C_SMBUS_I2C_BLOCK_DATA:
status = i2c_smbus_read_i2c_block_data(client, offset,
count, buf);
} else {
break;
case I2C_SMBUS_WORD_DATA:
status = i2c_smbus_read_word_data(client, offset);
if (status >= 0) {
buf[0] = status & 0xff;
buf[1] = status >> 8;
status = count;
}
break;
case I2C_SMBUS_BYTE_DATA:
status = i2c_smbus_read_byte_data(client, offset);
if (status >= 0) {
buf[0] = status;
status = count;
}
break;
default:
status = i2c_transfer(client->adapter, msg, 2);
if (status == 2)
status = count;
@@ -436,7 +461,7 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
{
struct at24_platform_data chip;
bool writable;
bool use_smbus = false;
int use_smbus = 0;
struct at24_data *at24;
int err;
unsigned i, num_addresses;
@@ -477,12 +502,19 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
err = -EPFNOSUPPORT;
goto err_out;
}
if (!i2c_check_functionality(client->adapter,
if (i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
use_smbus = I2C_SMBUS_I2C_BLOCK_DATA;
} else if (i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_READ_WORD_DATA)) {
use_smbus = I2C_SMBUS_WORD_DATA;
} else if (i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
use_smbus = I2C_SMBUS_BYTE_DATA;
} else {
err = -EPFNOSUPPORT;
goto err_out;
}
use_smbus = true;
}
if (chip.flags & AT24_FLAG_TAKE8ADDR)
@@ -568,11 +600,16 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id)
dev_info(&client->dev, "%zu byte %s EEPROM %s\n",
at24->bin.size, client->name,
writable ? "(writable)" : "(read-only)");
if (use_smbus == I2C_SMBUS_WORD_DATA ||
use_smbus == I2C_SMBUS_BYTE_DATA) {
dev_notice(&client->dev, "Falling back to %s reads, "
"performance will suffer\n", use_smbus ==
I2C_SMBUS_WORD_DATA ? "word" : "byte");
}
dev_dbg(&client->dev,
"page_size %d, num_addresses %d, write_max %d%s\n",
"page_size %d, num_addresses %d, write_max %d, use_smbus %d\n",
chip.page_size, num_addresses,
at24->write_max,
use_smbus ? ", use_smbus" : "");
at24->write_max, use_smbus);
/* export data to kernel code */
if (chip.setup)