David Brownell wrote: > On Friday 26 June 2009, Steven A. Falco wrote: >> + >> + /* >> + * If there are no chip selects at all, or if this is the special >> + * case of a non-existent (dummy) chip select, do nothing. >> + */ >> + >> + if (!hw->master->num_chipselect || hw->gpios[cs] == -EEXIST) >> + return; >> + > > I'm going to send this in, but please send a followup > patch making all this "non-existent (dummy) chip select" > stuff use the SPI_NO_CS flag. >
Not sure yet how this will work. GPIOs are detected during probe. of_get_gpio_flags() will return EEXIST for devices without a CS, and will return the gpio number for devices with a CS, but probe doesn't (currently) know anything about "struct spi_device". In fact, the devices don't exist until spi_bitbang_start is called, near the end of the probe. So, I've not figured out how the probe routine will set the new SPI_NO_CS flag on a per-device basis. There is one example of a ppc board calling spi_register_board_info, but even that board doesn't really use it, if a device tree exists. > >> + /* >> + * A count of zero implies a single SPI device without any >> chip-select. >> + * Note that of_gpio_count counts all gpios assigned to this spi >> master. >> + * This includes both "null" gpio's and real ones. >> + */ > > > _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
