it seem have several serious problems to use this deriver, does it can be fixed? or any patch is available? thank for help.
i2c-at91.c i2c bus driver have been marked as broken since linux-2.6.24(???)

config I2C_AT91
tristate "Atmel AT91 I2C Two-Wire interface (TWI)"
depends on ARCH_AT91 && EXPERIMENTAL && BROKEN
help
This supports the use of the I2C interface on Atmel AT91
processors.

This driver is BROKEN because the controller which it uses
will easily trigger RX overrun and TX underrun errors. Using
low I2C clock rates may partially work around those issues
on some systems. Another serious problem is that there is no
documented way to issue repeated START conditions, as needed
to support combined I2C messages. Use the i2c-gpio driver
unless your system can cope with those limitations.