[PATCH V1 3/5] mtd: m25p80: add the quad-read support

Brian Norris computersforpeace at gmail.com
Fri Aug 23 07:53:09 EDT 2013


On 08/23/2013 04:46 AM, Brian Norris wrote:
> (Now that I've been pointed to the support merged into the SPI tree...)
>
> Aren't the following new DT properties (for the SPI slave) sufficient?
>
> spi-rx-nbits
> spi-tx-nbits
...
> They're already in the following commit:
>
> commit f477b7fb13df2b843997559ff34e87d054ba6538
> Author: wangyuhang <wangyuhang2014 at gmail.com>
> Date:   Sun Aug 11 18:15:17 2013 +0800
>
>      spi: DUAL and QUAD support
>
>      fix the previous patch some mistake below:
>      1. DT in slave node, use "spi-tx-nbits = <1/2/4>" in place of using
>         "spi-tx-dual, spi-tx-quad" directly, same to rx. So correct the
>         previous way to get the property in @of_register_spi_devices().
>      2. Change the value of transfer bit macro(SPI_NBITS_SINGLE, SPI_NBITS_DUAL
>         SPI_NBITS_QUAD) to 0x01, 0x02 and 0x04 to match the actual wires.
>      3. Add the following check
>         (1)keep the tx_nbits and rx_nbits in spi_transfer is not beyond the
>            single, dual and quad.
>         (2)keep tx_nbits and rx_nbits are contained by @spi_device->mode
>            example: if @spi_device->mode = DUAL, then tx/rx_nbits can not be set
>                     to QUAD(SPI_NBITS_QUAD)
>         (3)if "@spi_device->mode & SPI_3WIRE", then tx/rx_nbits should be in
>            single(SPI_NBITS_SINGLE)
>
>      Signed-off-by: wangyuhang <wangyuhang2014 at gmail.com>
>      Signed-off-by: Mark Brown <broonie at linaro.org>

Speaking of which, the new device-tree properties are not documented in 
Documentation/devicetree/bindings/spi/spi-bus.txt yet.

Brian



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