| Message ID | 20210519091613.7343-1-stephan@gerhold.net |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | [v2,1/2] dt-bindings: net: nfc: s3fwrn5: Add optional clock | expand |
| Context | Check | Description |
|---|---|---|
| robh/checkpatch | success | |
| robh/dt-meta-schema | success | |
| robh/dtbs-check | success |
On 19/05/2021 05:16, Stephan Gerhold wrote: > On some systems, S3FWRN5 depends on having an external clock enabled > to function correctly. Allow declaring that clock in the device tree. > > Signed-off-by: Stephan Gerhold <stephan@gerhold.net> > --- > Changes in v2: Minor change in commit message only > v1: https://lore.kernel.org/netdev/20210518133935.571298-1-stephan@gerhold.net/ > --- > .../devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml | 5 +++++ > 1 file changed, 5 insertions(+) > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Best regards, Krzysztof
On 19/05/2021 05:16, Stephan Gerhold wrote: > S3FWRN5 depends on a clock input ("XI" pin) to function properly. > Depending on the hardware configuration this could be an always-on > oscillator or some external clock that must be explicitly enabled. > > So far we assumed that the clock is always-on. > Make the driver request an (optional) clock from the device tree > and make sure the clock is running before starting S3FWRN5. > > Note: S3FWRN5 asserts "GPIO2" whenever it needs the clock input to > function correctly. On some hardware configurations, GPIO2 is > connected directly to an input pin of the external clock provider > (e.g. the main PMIC of the SoC). In that case, it can automatically > AND the clock enable bit and clock request from S3FWRN5 so that > the clock is actually only enabled when needed. > > It is also conceivable that on some other hardware configuration > S3FWRN5's GPIO2 might be connected as a regular GPIO input > of the SoC. In that case, follow-up patches could extend the > driver to request the GPIO, set up an interrupt and only enable > the clock when requested by S3FWRN5. > > Signed-off-by: Stephan Gerhold <stephan@gerhold.net> > --- > This allows NFC to work properly on the Samsung Galaxy A3/A5 (2015). > > Changes in v2: Rewrite commit message and comment based on discussion > > Note: I tried to explain the setup a bit better but dropped most of > the explanations about the exact configuration on the Samsung > Galaxy A5. I think the HW-specific details were more confusing > than helping. :) > > v1: https://lore.kernel.org/netdev/20210518133935.571298-2-stephan@gerhold.net/ > --- > drivers/nfc/s3fwrn5/i2c.c | 30 ++++++++++++++++++++++++++++-- > 1 file changed, 28 insertions(+), 2 deletions(-) > Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> Best regards, Krzysztof
Hello: This series was applied to netdev/net-next.git (refs/heads/master): On Wed, 19 May 2021 11:16:12 +0200 you wrote: > On some systems, S3FWRN5 depends on having an external clock enabled > to function correctly. Allow declaring that clock in the device tree. > > Signed-off-by: Stephan Gerhold <stephan@gerhold.net> > --- > Changes in v2: Minor change in commit message only > v1: https://lore.kernel.org/netdev/20210518133935.571298-1-stephan@gerhold.net/ > > [...] Here is the summary with links: - [v2,1/2] dt-bindings: net: nfc: s3fwrn5: Add optional clock https://git.kernel.org/netdev/net-next/c/9cc52f5a533a - [v2,2/2] nfc: s3fwrn5: i2c: Enable optional clock from device tree https://git.kernel.org/netdev/net-next/c/340f42f7ff0b You are awesome, thank you! -- Deet-doot-dot, I am a bot. https://korg.docs.kernel.org/patchwork/pwbot.html
diff --git a/Documentation/devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml b/Documentation/devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml index 477066e2b821..081742c2b726 100644 --- a/Documentation/devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml +++ b/Documentation/devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml @@ -27,6 +27,9 @@ properties: reg: maxItems: 1 + clocks: + maxItems: 1 + wake-gpios: maxItems: 1 description: @@ -80,6 +83,8 @@ examples: en-gpios = <&gpf1 4 GPIO_ACTIVE_HIGH>; wake-gpios = <&gpj0 2 GPIO_ACTIVE_HIGH>; + + clocks = <&rpmcc 20>; }; }; # UART example on Raspberry Pi
On some systems, S3FWRN5 depends on having an external clock enabled to function correctly. Allow declaring that clock in the device tree. Signed-off-by: Stephan Gerhold <stephan@gerhold.net> --- Changes in v2: Minor change in commit message only v1: https://lore.kernel.org/netdev/20210518133935.571298-1-stephan@gerhold.net/ --- .../devicetree/bindings/net/nfc/samsung,s3fwrn5.yaml | 5 +++++ 1 file changed, 5 insertions(+)