struct at24_platform_data chip;
kernel_ulong_t magic = 0;
bool writable;
- int use_smbus = 0;
- int use_smbus_write = 0;
struct at24_data *at24;
int err;
unsigned i, num_addresses;
if (chip.flags & AT24_FLAG_MAC && chip.byte_len == 4)
chip.byte_len = 6;
- /* Use I2C operations unless we're stuck with SMBus extensions. */
- if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
- if (chip.flags & AT24_FLAG_ADDR16)
- return -EPFNOSUPPORT;
-
- 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 {
- return -EPFNOSUPPORT;
- }
-
- if (i2c_check_functionality(client->adapter,
- I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
- use_smbus_write = I2C_SMBUS_I2C_BLOCK_DATA;
- } else if (i2c_check_functionality(client->adapter,
- I2C_FUNC_SMBUS_WRITE_BYTE_DATA)) {
- use_smbus_write = I2C_SMBUS_BYTE_DATA;
- chip.page_size = 1;
- }
- }
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C) &&
+ !i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_WRITE_I2C_BLOCK))
+ chip.page_size = 1;
if (chip.flags & AT24_FLAG_TAKE8ADDR)
num_addresses = 8;
writable = !(chip.flags & AT24_FLAG_READONLY);
if (writable) {
- if (!use_smbus || use_smbus_write) {
-
- unsigned write_max = chip.page_size;
-
- if (write_max > io_limit)
- write_max = io_limit;
- if (use_smbus && write_max > I2C_SMBUS_BLOCK_MAX)
- write_max = I2C_SMBUS_BLOCK_MAX;
- at24->write_max = write_max;
- } else {
- dev_warn(&client->dev,
- "cannot write due to controller restrictions.");
- }
+ at24->write_max = min_t(unsigned int, chip.page_size, io_limit);
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C) &&
+ at24->write_max > I2C_SMBUS_BLOCK_MAX)
+ at24->write_max = I2C_SMBUS_BLOCK_MAX;
}
/* use dummy devices for multiple-address chips */
dev_info(&client->dev, "%u byte %s EEPROM, %s, %u bytes/write\n",
chip.byte_len, client->name,
writable ? "writable" : "read-only", at24->write_max);
- 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");
- }
/* export data to kernel code */
if (chip.setup)