Dear Wolfram Sang, > This I2C master can do DMA and PIOQUEUE (PIO with FIFO). Originally, > only PIOQEUE PIOQUEUE ;-) > was supported, then DMA support was added. The original > intention was to keep PIOQUEUE since it has less overhead what is nice > for small transfers. However, runtime switching between PIOQEUE and DMA > depending on the transfer size never worked despite a lot of trying. > Since PIOQUEUE mode itself was flaky (polling at places where interrupts > failed to work) and the implementation also imposed a size limit for > transfers, it is best to remove the support altogether which makes the > driver a lot cleaner and more robust. If somebody really wants less > overhead, plain PIO mode could still be implemented with the addidtional > advantage that this mode is also available on MX23, too. Yes, looks to be the way to go. Reviewed-by: Marek Vasut <marex@xxxxxxx> Thanks [...] Best regards, Marek Vasut -- 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
