On Mon, Feb 13, 2017 at 12:38 AM, Heiko Schocher [off-list ref] wrote:

Hello Rob,


Am 10.02.2017 um 16:51 schrieb Rob Herring:

quoted

On Tue, Feb 07, 2017 at 06:22:04AM +0100, Heiko Schocher wrote:

quoted

From: Guan Ben <redacted>

Make the EN2 pin optional. This is useful for boards,
which have this pin fix wired, for example to ground.

Signed-off-by: Guan Ben <redacted>
Signed-off-by: Mark Jonas <redacted>
Signed-off-by: Heiko Schocher <redacted>

---

  .../devicetree/bindings/net/nfc/trf7970a.txt       |  4 ++--
  drivers/nfc/trf7970a.c                             | 26
++++++++++++----------
  2 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt

b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
index 32b35a0..5889a3d 100644

--- a/Documentation/devicetree/bindings/net/nfc/trf7970a.txt
+++ b/Documentation/devicetree/bindings/net/nfc/trf7970a.txt

@@ -5,8 +5,8 @@ Required properties:
  - spi-max-frequency: Maximum SPI frequency (<= 2000000).
  - interrupt-parent: phandle of parent interrupt handler.
  - interrupts: A single interrupt specifier.
-- ti,enable-gpios: Two GPIO entries used for 'EN' and 'EN2' pins on the
-  TRF7970A.
+- ti,enable-gpios: One or two GPIO entries used for 'EN' and 'EN2' pins

on the
+  TRF7970A. EN2 is optional.

Could EN ever be optional/fixed? If so, perhaps deprecate this property
and do 2 properties, one for each pin.

The hardware I have has the EN2 pin fix connected to ground. Looking
into http://www.ti.com/lit/ds/slos743k/slos743k.pdf page 19 table 6-3
and 6-4 the EN2 pin is a don;t core if EN = 1. If EN = 0 EN2 pin
selects between Power Down and Sleep Mode ... I see no reason why
this is not possible/allowed ...

Hmm.. I do not like the idea of deprecating the "ti,enable-gpios"
property into 2 seperate properties ... but if this would be a reason
for not accepting this patch, I can do this ... How should I name
the 2 new properties?

I guess if this ever happens, then we just add "ti,enable2-gpios" and
ti,enable-gpios continues to point to EN. We don't need to deprecate
anything (or maybe just deprecate having both GPIOs on single
property).

In that case,

Acked-by: Rob Herring <robh@kernel.org>

"ti,pin-enable"  and "ti,pin-enable2" ?

bye,
Heiko
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