> Hello, > > There's been this patch going on, which adds DMA mode into MXS i2c driver: > https://patchwork.kernel.org/patch/1174051/ > > Recent nitpick was about toggling the PIOQUEUE (almost like PIO, only > transfer mode in current implementation) vs. DMA mode (newly added) on a > per-bus basis. > > Current implementation in the patch adds a DT property, "fsl,use-pio" > (shall be changed to "fsl,use-pioqueue", but that's irrelevant) to select > between the PIOQUEUE and DMA mode on per-bus basis. > > There was now a suggestion to dump this property and use kernel module > parameter instead. This obviously disallows to configure this behavior on > per-bus basis. Consider a scenario where small transfers happens on one > bus (possibly from a sensor) and large transfers on the other bus (eg. i2c > EEPROM). In such scenario, it's beneficial to enable PIOQUEUE mode for the > sensor and DMA mode for the EEPROM to minimize the overall overhead. > > The mixed mode (PIOQ for small data and DMA for large data transfers) isn't > supported yet. > > Please advise. > > Best regards, > Marek Vasut BUMP? -- 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
