On Mon, 2016-06-27 at 20:19 +0900, Akinobu Mita wrote: > The rtc-ds1302 driver now implemented using SPI 3wire mode. > But I would like to access it with using three wires connected to > GPIO > lines. > > This adds abstraction layer for DS1302 register access in order to > prepare to support for using GPIO lines. This enables to share > common > code between SPI driver and GPIO driver. I don't think this is the right way. DS-1302 is an SPI device, not a GPIO one. It can be connected to a hardware SPI controller or a software one (on top of GPIO or memory). Your patch re-adds Microwire SPI control logic to RTC subsystem, which was cleared by my rewrite of drivers/rtc/rtc-ds1302.c. The logic is already present in bitbang_txrx_be_cpha0_lsb() in drivers/spi/spi- lp8841-rtc.c. I still think you need to implement spi-gpio-3wire with LSB-first support in SPI subsystem instead. It wasn't done when I was adding LP8841 support, because LP8841 was the only use case of Microwire SPI control logic. If you add it, drivers/spi/spi-lp8841-rtc.c can be removed and replaced by a GPIO driver to host a new spi-gpio-3wire device. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
