diff options
Diffstat (limited to 'drivers/i2c/busses/Kconfig')
-rw-r--r-- | drivers/i2c/busses/Kconfig | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig index b4aaa1bd672..da77c37caf1 100644 --- a/drivers/i2c/busses/Kconfig +++ b/drivers/i2c/busses/Kconfig @@ -290,18 +290,21 @@ comment "I2C system bus drivers (mostly embedded / system-on-chip)" config I2C_AT91 tristate "Atmel AT91 I2C Two-Wire interface (TWI)" - depends on ARCH_AT91 && EXPERIMENTAL && BROKEN + depends on ARCH_AT91 && EXPERIMENTAL 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 + A serious problem is that there is no documented way to issue + repeated START conditions for more than two messages, as needed to support combined I2C messages. Use the i2c-gpio driver - unless your system can cope with those limitations. + unless your system can cope with this limitation. + + Caution! at91rm9200, at91sam9261, at91sam9260, at91sam9263 devices + don't have clock stretching in transmission mode. For that reason, + you can encounter underrun issues causing premature stop sendings if + the latency to fill the transmission register is too long. If you + are facing this situation, use the i2c-gpio driver. config I2C_AU1550 tristate "Au1550/Au1200/Au1300 SMBus interface" |