> Noralf Trønnes <noralf@xxxxxxxxxxx> hat am 29. September 2016 um 00:22 > geschrieben: > > > > Den 29.09.2016 00:00, skrev Eric Anholt: > > Noralf Trønnes <noralf@xxxxxxxxxxx> writes: > > > >> If an unexpected TXW or RXR interrupt occurs (msg_buf_remaining == 0), > >> the driver has no way to fill/drain the FIFO to stop the interrupts. > >> In this case the controller has to be disabled and the transfer > >> completed to avoid hang. > >> > >> (CLKT | ERR) and DONE interrupts are completed in their own paths, and > >> the controller is disabled in the transfer function after completion. > >> Unite the code paths and do disabling inside the interrupt routine. > >> > >> Clear interrupt status bits in the united completion path instead of > >> trying to do it on every interrupt which isn't necessary. > >> Only CLKT, ERR and DONE can be cleared that way. > >> > >> Add the status value to the error value in case of TXW/RXR errors to > >> distinguish them from the other S_LEN error. > > I was surprised that not writing the TXW/RXR bits on handling their > > interrupts was OK, given that we were doing so before, but it's a level > > interrupt and those bits are basically ignored on write. > > > > This patch and 3, 4, and 6 are: > > > > Reviewed-by: Eric Anholt <eric@xxxxxxxxxx> > > > > Patch 5 is: > > > > Acked-by: Eric Anholt <eric@xxxxxxxxxx> > > > > Note for future debug: The I2C_C_CLEAR on errors will take some time to > > resolve -- if you were in non-idle state and I2C_C_READ, it sets an > > abort_rx flag and runs through the state machine to send a NACK and a > > STOP, I think. Since we're setting CLEAR without I2CEN, that NACK will > > be hanging around queued up for next time we start the engine. > > Maybe you're able to explain the issues I had with reset: > https://github.com/raspberrypi/linux/issues/1653 > > Should we put your note into the commit message? > It will most likely be lost if it just stays in this email. I prefer to have this kind of information as a code comment. > > Noralf. > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
