[PATCH v2 0/3] Update cros-ec-spi for fingerprint devices

[PATCH v2 0/3] Update cros-ec-spi for fingerprint devices

[Stephen Boyd]

This patch series introduces a DT binding for chromeos fingerprint
devices and then implements support to boot those processors during
driver probe if the BIOS hasn't done it already.

Changes from v1 (https://lore.kernel.org/r/20220314232214.4183078-1-swboyd@chromium.org):
 * Properly do the boot sequence
 * Add a message that we're booting and delaying a while
 * Fix typo in commit text
 * Change binding to not spell out reset-gpios and indicate that boot0
   is about asserting boot mode
 * Split device id to different patch as it's a different topic from
   booting

Stephen Boyd (3):
  dt-bindings: chrome: Add ChromeOS fingerprint binding
  platform/chrome: cros_ec_spi: Match cros-ec-fp compatible
  platform/chrome: cros_ec_spi: Boot fingerprint processor during probe

 .../bindings/chrome/google,cros-ec-fp.yaml    | 85 +++++++++++++++++++
 drivers/platform/chrome/cros_ec_spi.c         | 44 +++++++++-
 2 files changed, 126 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml

Cc: Rob Herring <robh+dt@kernel.org>
Cc: <devicetree@vger.kernel.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Craig Hesling <hesling@chromium.org>
Cc: Tom Hughes <tomhughes@chromium.org>
Cc: Alexandru M Stan <amstan@chromium.org>
Cc: Tzung-Bi Shih <tzungbi@kernel.org>

base-commit: ffb217a13a2eaf6d5bd974fc83036a53ca69f1e2
-- 
https://chromeos.dev

[PATCH v2 1/3] dt-bindings: chrome: Add ChromeOS fingerprint binding

[Stephen Boyd]

Add a binding to describe the fingerprint processor found on Chromebooks
with a fingerprint sensor.

Cc: Rob Herring <robh+dt@kernel.org>
Cc: <devicetree@vger.kernel.org>
Cc: Guenter Roeck <groeck@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Craig Hesling <hesling@chromium.org>
Cc: Tom Hughes <tomhughes@chromium.org>
Cc: Alexandru M Stan <amstan@chromium.org>
Cc: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---
 .../bindings/chrome/google,cros-ec-fp.yaml    | 85 +++++++++++++++++++
 1 file changed, 85 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml

diff --git a/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
new file mode 100644
index 000000000000..ba4212e6b583
--- /dev/null
+++ b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
@@ -0,0 +1,85 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/chrome/google,cros-ec-fp.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ChromeOS Embedded Fingerprint Controller
+
+description:
+  Google's ChromeOS embedded fingerprint controller is a device which
+  implements fingerprint functionality such as unlocking a Chromebook
+  without typing a password.
+
+maintainers:
+  - Tom Hughes <tomhughes@chromium.org>
+
+properties:
+  compatible:
+    const: google,cros-ec-fp
+
+  reg:
+    maxItems: 1
+
+  spi-max-frequency:
+    maximum: 3000000
+
+  interrupts:
+    maxItems: 1
+
+  reset-gpios: true
+  boot0-gpios:
+    maxItems: 1
+    description: Assert for bootloader mode.
+
+  vdd-supply: true
+
+  google,cros-ec-spi-pre-delay:
+    description:
+      This property specifies the delay in usecs between the
+      assertion of the CS and the first clock pulse.
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - default: 0
+      - minimum: 0
+
+  google,cros-ec-spi-msg-delay:
+    description:
+      This property specifies the delay in usecs between messages.
+    allOf:
+      - $ref: /schemas/types.yaml#/definitions/uint32
+      - default: 0
+      - minimum: 0
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - reset-gpios
+  - boot0-gpios
+  - vdd-supply
+  - spi-max-frequency
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+    #include <dt-bindings/gpio/gpio.h>
+    spi {
+      #address-cells = <0x1>;
+      #size-cells = <0x0>;
+      ec@0 {
+        compatible = "google,cros-ec-fp";
+        reg = <0>;
+        interrupt-parent = <&gpio_controller>;
+        interrupts = <4 IRQ_TYPE_LEVEL_LOW>;
+        spi-max-frequency = <3000000>;
+        google,cros-ec-spi-msg-delay = <37>;
+        google,cros-ec-spi-pre-delay = <5>;
+        reset-gpios = <&gpio_controller 5 GPIO_ACTIVE_LOW>;
+        boot0-gpios = <&gpio_controller 10 GPIO_ACTIVE_HIGH>;
+        vdd-supply = <&pp3300_fp_mcu>;
+      };
+    };
+...
-- 
https://chromeos.dev

Re: [PATCH v2 1/3] dt-bindings: chrome: Add ChromeOS fingerprint binding

[Krzysztof Kozlowski]

On 17/03/2022 01:58, Stephen Boyd wrote:
> Add a binding to describe the fingerprint processor found on Chromebooks
> with a fingerprint sensor.
> 
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: <devicetree@vger.kernel.org>
> Cc: Guenter Roeck <groeck@chromium.org>
> Cc: Douglas Anderson <dianders@chromium.org>
> Cc: Craig Hesling <hesling@chromium.org>
> Cc: Tom Hughes <tomhughes@chromium.org>
> Cc: Alexandru M Stan <amstan@chromium.org>
> Cc: Tzung-Bi Shih <tzungbi@kernel.org>
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> ---
>  .../bindings/chrome/google,cros-ec-fp.yaml    | 85 +++++++++++++++++++
>  1 file changed, 85 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
> 
> diff --git a/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
> new file mode 100644
> index 000000000000..ba4212e6b583
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml

Hm, so chrome starts to be its own subsystem? I see USB connector
bindings are already there, instead of usb directory.

Is there anything special about Chrome that it is equal to subsystem or
architecture? Once second file ends up there, this will encourage more
of such patterns.

> @@ -0,0 +1,85 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/chrome/google,cros-ec-fp.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ChromeOS Embedded Fingerprint Controller
> +
> +description:
> +  Google's ChromeOS embedded fingerprint controller is a device which
> +  implements fingerprint functionality such as unlocking a Chromebook
> +  without typing a password.
> +
> +maintainers:
> +  - Tom Hughes <tomhughes@chromium.org>
> +
> +properties:
> +  compatible:
> +    const: google,cros-ec-fp
> +
> +  reg:
> +    maxItems: 1
> +
> +  spi-max-frequency:
> +    maximum: 3000000
> +
> +  interrupts:
> +    maxItems: 1
> +
> +  reset-gpios: true
> +  boot0-gpios:
> +    maxItems: 1
> +    description: Assert for bootloader mode.
> +
> +  vdd-supply: true
> +
> +  google,cros-ec-spi-pre-delay:

Use proper unit suffix, so "-us". No need for type then.


> +    description:
> +      This property specifies the delay in usecs between the
> +      assertion of the CS and the first clock pulse.
> +    allOf:

No need for allOf. Just put default/minimum directly.

> +      - $ref: /schemas/types.yaml#/definitions/uint32
> +      - default: 0
> +      - minimum: 0
> +
> +  google,cros-ec-spi-msg-delay:
> +    description:
> +      This property specifies the delay in usecs between messages.
> +    allOf:
> +      - $ref: /schemas/types.yaml#/definitions/uint32
> +      - default: 0
> +      - minimum: 0

Same here (proper suffix + allOf).



Best regards,
Krzysztof

Re: [PATCH v2 1/3] dt-bindings: chrome: Add ChromeOS fingerprint binding

[Stephen Boyd]

Quoting Krzysztof Kozlowski (2022-03-17 02:34:31)
> On 17/03/2022 01:58, Stephen Boyd wrote:
> > Add a binding to describe the fingerprint processor found on Chromebooks
> > with a fingerprint sensor.
> >
> > Cc: Rob Herring <robh+dt@kernel.org>
> > Cc: <devicetree@vger.kernel.org>
> > Cc: Guenter Roeck <groeck@chromium.org>
> > Cc: Douglas Anderson <dianders@chromium.org>
> > Cc: Craig Hesling <hesling@chromium.org>
> > Cc: Tom Hughes <tomhughes@chromium.org>
> > Cc: Alexandru M Stan <amstan@chromium.org>
> > Cc: Tzung-Bi Shih <tzungbi@kernel.org>
> > Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> > ---
> >  .../bindings/chrome/google,cros-ec-fp.yaml    | 85 +++++++++++++++++++
> >  1 file changed, 85 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
> > new file mode 100644
> > index 000000000000..ba4212e6b583
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/chrome/google,cros-ec-fp.yaml
>
> Hm, so chrome starts to be its own subsystem? I see USB connector
> bindings are already there, instead of usb directory.
>
> Is there anything special about Chrome that it is equal to subsystem or
> architecture? Once second file ends up there, this will encourage more
> of such patterns.

I don't see a problem.

>
> > @@ -0,0 +1,85 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/chrome/google,cros-ec-fp.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: ChromeOS Embedded Fingerprint Controller
> > +
> > +description:
> > +  Google's ChromeOS embedded fingerprint controller is a device which
> > +  implements fingerprint functionality such as unlocking a Chromebook
> > +  without typing a password.
> > +
> > +maintainers:
> > +  - Tom Hughes <tomhughes@chromium.org>
> > +
> > +properties:
> > +  compatible:
> > +    const: google,cros-ec-fp
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  spi-max-frequency:
> > +    maximum: 3000000
> > +
> > +  interrupts:
> > +    maxItems: 1
> > +
> > +  reset-gpios: true
> > +  boot0-gpios:
> > +    maxItems: 1
> > +    description: Assert for bootloader mode.
> > +
> > +  vdd-supply: true
> > +
> > +  google,cros-ec-spi-pre-delay:
>
> Use proper unit suffix, so "-us". No need for type then.
>

This is copy pasted from the cros-ec binding and the driver is already
looking for this property. Given that, there's no need to have this here
right now as we can always add this to the binding when/if it is needed.
I mostly put this here for completeness. I'll remove it.