2016-06-23 4:04 GMT+09:00 Linus Walleij <linus.walleij@xxxxxxxxxx>: > On Mon, Jun 20, 2016 at 1:06 PM, Akinobu Mita <akinobu.mita@xxxxxxxxx> wrote: > >> I was also trying to support SPI interface for this driver and found >> that we can't simply use regmap_init_spi(). >> >> Quote from 5.3 SPI interface in BMP280 datasheet: >> >> In SPI mode, only 7 bits of the register addresses are used; the MSB of >> register address is not used and replaced by a read/write bit (RW = ‘0’ >> for write and RW = ‘1’ for read). Example: address 0xF7 is accessed by >> using SPI register address 0x77. For write access, the byte 0x77 is >> transferred, for read access, the byte 0xF7 is transferred. >> >> The write operation used by regmap_init_spi() doesn't replace the RW bit. >> So we need custom regmap_bus like below. > > Aha! OK I added your bus implementation and will add your Signed-off to > the patch as well, OK? OK > It would be great if you could also test the result. I've tested v2 patches with fixing undefined symbols error, missing NULL entry in of_device_id, and missing MODULE_LICENSE in bmp280.ko. The SPI interface for BMP280 works fine as well as I2C interface. Tested-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
