[U-Boot] [PATCH v3 11/11] spi: cadence_qspi: Support specifying the sample edge used

[Jagan Teki]

On Mon, Dec 5, 2016 at 11:31 AM, Phil Edworthy
<phil.edworthy at renesas.com> wrote:
> HI Jagan,
>
> On 05 December 2016 10:26, Jagan Teki wrote:
>> On Mon, Dec 5, 2016 at 11:09 AM, Phil Edworthy
>> <phil.edworthy at renesas.com> wrote:
>> > Hi Jagan,
>> >
>> > On 02 December 2016 14:23, Jagan Teki wrote:
>> >> On Tue, Nov 29, 2016 at 6:28 PM, Phil Edworthy
>> >> <phil.edworthy at renesas.com> wrote:
>> >> > Introduce a new DT property to specify whether the QSPI Controller
>> >> > samples the data on a rising edge. The default is falling edge.
>> >> > Some versions of the QSPI Controller do not implement this bit, in
>> >> > which case the property should be omitted.
>> >> >
>> >> > Signed-off-by: Phil Edworthy <phil.edworthy at renesas.com>
>> >> > ---
>> >> >  v3:
>> >> >   - Patch split so this one only has code related to the subject.
>> >> >   - Commit message updated.
>> >> >  v2:
>> >> >   - Change name of DT prop and provide details of what it does.
>> >> >     Whilst at it, move the code to read the "sram-size" property
>> >> >     into the other code that reads properties from the node, rather
>> >> >     than the SF subnode.
>> >> >
>> >> >     Also change the code to use a bool for the bypass arg.
>> >> > ---
>> >> >  doc/device-tree-bindings/spi/spi-cadence.txt |  2 ++
>> >> >  drivers/spi/cadence_qspi.c                   | 10 +++++++---
>> >> >  drivers/spi/cadence_qspi.h                   |  3 ++-
>> >> >  drivers/spi/cadence_qspi_apb.c               |  8 +++++++-
>> >> >  4 files changed, 18 insertions(+), 5 deletions(-)
>> >> >
>> >> > diff --git a/doc/device-tree-bindings/spi/spi-cadence.txt b/doc/device-tree-
>> >> bindings/spi/spi-cadence.txt
>> >> > index c1e2233..94c800b 100644
>> >> > --- a/doc/device-tree-bindings/spi/spi-cadence.txt
>> >> > +++ b/doc/device-tree-bindings/spi/spi-cadence.txt
>> >> > @@ -26,3 +26,5 @@ connected flash properties
>> >> >                           select (n_ss_out).
>> >> >  - tslch-ns             : Delay in master reference clocks between setting
>> >> >                           n_ss_out low and first bit transfer
>> >> > +- sample-edge-rising   : Data outputs from flash memory will be sampled on
>> >> the
>> >> > +                         rising edge. Default is falling edge.
>> >>
>> >> Code look reasonable, but how Linux handling this with the same dt
>> >> property, any idea? I couldn't find it either.
>> > The Linux driver does not yet have this property. Is there a policy to add new
>> > props to Linux first?
>>
>> If the same/equal code used in Linux better to have the same property
>> instead of another name used in U-boot?
> Of course, but I cannot see this in Linux:
> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/Documentation/devicetree/bindings/spi/spi-cadence.txt

Yeah, I saw this. Do you have any idea how Linux handling this sample edge?

thanks!
-- 
Jagan Teki
Free Software Engineer | www.openedev.com
U-Boot, Linux | Upstream Maintainer
Hyderabad, India.