diff mbox series

[1/2] dt-bindings: reset: Add TPS380x documentation

Message ID 20220525142019.3615253-1-m.felsch@pengutronix.de
State Superseded
Headers show
Series [1/2] dt-bindings: reset: Add TPS380x documentation | expand

Commit Message

Marco Felsch May 25, 2022, 2:20 p.m. UTC
Add device-tree binding documentation for the tps380x reset driver. The
binding uses enum to make it easy to add more devices from that family.

Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
---
 .../bindings/reset/ti,tps380x-reset.yaml      | 49 +++++++++++++++++++
 1 file changed, 49 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/reset/ti,tps380x-reset.yaml

Comments

Krzysztof Kozlowski May 26, 2022, 7:53 p.m. UTC | #1
On 25/05/2022 16:20, Marco Felsch wrote:
> Add device-tree binding documentation for the tps380x reset driver. The
> binding uses enum to make it easy to add more devices from that family.
> 
> Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof
Krzysztof Kozlowski May 26, 2022, 7:54 p.m. UTC | #2
On 25/05/2022 16:20, Marco Felsch wrote:
> The TI TPS380x family [1] is a volatage supervisor with a dedicated
> manual reset (mr) line input and a reset output. The chip(s) have a
> build in reset delay, depending on the chip partnumber. This simple
> driver addresses this so the cosumer don't need to care about it.
> 
> [1] https://www.ti.com/product/TPS3801
> 
> Signed-off-by: Marco Felsch <m.felsch@pengutronix.de>
> ---
>  drivers/reset/Kconfig         |   8 +++
>  drivers/reset/Makefile        |   1 +
>  drivers/reset/reset-tps380x.c | 130 ++++++++++++++++++++++++++++++++++
>  3 files changed, 139 insertions(+)
>  create mode 100644 drivers/reset/reset-tps380x.c
> 
> diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
> index e0fc80e041ea..e2eb616af812 100644
> --- a/drivers/reset/Kconfig
> +++ b/drivers/reset/Kconfig
> @@ -256,6 +256,14 @@ config RESET_TI_SYSCON
>  	  you wish to use the reset framework for such memory-mapped devices,
>  	  say Y here. Otherwise, say N.
>  
> +config RESET_TI_TPS380X
> +	tristate "TI TPS380x Reset Driver"
> +	select GPIOLIB
> +	help
> +	  This enables the reset driver support for TI TPS380x devices. If
> +	  you wish to use the reset framework for such devices, say Y here.
> +	  Otherwise, say N.
> +
>  config RESET_TN48M_CPLD
>  	tristate "Delta Networks TN48M switch CPLD reset controller"
>  	depends on MFD_TN48M_CPLD || COMPILE_TEST
> diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
> index a80a9c4008a7..66399b92b1bb 100644
> --- a/drivers/reset/Makefile
> +++ b/drivers/reset/Makefile
> @@ -33,6 +33,7 @@ obj-$(CONFIG_RESET_STARFIVE_JH7100) += reset-starfive-jh7100.o
>  obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o
>  obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o
>  obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o
> +obj-$(CONFIG_RESET_TI_TPS380X) += reset-tps380x.o
>  obj-$(CONFIG_RESET_TN48M_CPLD) += reset-tn48m.o
>  obj-$(CONFIG_RESET_UNIPHIER) += reset-uniphier.o
>  obj-$(CONFIG_RESET_UNIPHIER_GLUE) += reset-uniphier-glue.o
> diff --git a/drivers/reset/reset-tps380x.c b/drivers/reset/reset-tps380x.c
> new file mode 100644
> index 000000000000..fd2c0929ae2d
> --- /dev/null
> +++ b/drivers/reset/reset-tps380x.c
> @@ -0,0 +1,130 @@
> +// SPDX-License-Identifier: GPL-2.0-or-later
> +/*
> + * TI TPS380x Supply Voltage Supervisor and Reset Controller Driver
> + *
> + * Copyright (C) 2022 Pengutronix, Marco Felsch <kernel@pengutronix.de>
> + *
> + * Based on Simple Reset Controller Driver
> + *
> + * Copyright (C) 2017 Pengutronix, Philipp Zabel <kernel@pengutronix.de>
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/reset-controller.h>
> +
> +struct tps380x_reset {
> +	struct reset_controller_dev	rcdev;
> +	struct gpio_desc		*reset_gpio;
> +	unsigned int			reset_ms;
> +};
> +
> +struct tps380x_reset_devdata {
> +	unsigned int min_reset_ms;
> +	unsigned int typ_reset_ms;
> +	unsigned int max_reset_ms;
> +};
> +
> +static inline
> +struct tps380x_reset *to_tps380x_reset(struct reset_controller_dev *rcdev)
> +{
> +	return container_of(rcdev, struct tps380x_reset, rcdev);
> +}
> +
> +static int
> +tps380x_reset_assert(struct reset_controller_dev *rcdev, unsigned long id)
> +{
> +	struct tps380x_reset *tps380x = to_tps380x_reset(rcdev);
> +
> +	gpiod_set_value_cansleep(tps380x->reset_gpio, 1);
> +
> +	return 0;
> +}
> +
> +static int
> +tps380x_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id)
> +{
> +	struct tps380x_reset *tps380x = to_tps380x_reset(rcdev);
> +
> +	gpiod_set_value_cansleep(tps380x->reset_gpio, 0);
> +	msleep(tps380x->reset_ms);
> +
> +	return 0;
> +}
> +
> +const struct reset_control_ops reset_tps380x_ops = {

This looks static.


Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/reset/ti,tps380x-reset.yaml b/Documentation/devicetree/bindings/reset/ti,tps380x-reset.yaml
new file mode 100644
index 000000000000..afc835eda0ef
--- /dev/null
+++ b/Documentation/devicetree/bindings/reset/ti,tps380x-reset.yaml
@@ -0,0 +1,49 @@ 
+# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/reset/ti,tps380x-reset.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: TI TPS380x reset controller node bindings
+
+maintainers:
+  - Marco Felsch <kernel@pengutronix.de>
+
+description: |
+  The TPS380x family [1] of supervisory circuits monitor supply voltages to
+  provide circuit initialization and timing supervision. The devices assert a
+  RESET signal if the voltage drops below a preset threshold or upon a manual
+  reset input (MR). The RESET output remains asserted for the factory
+  programmed delay after the voltage return above its threshold or after the
+  manual reset input is released.
+
+  [1] https://www.ti.com/product/TPS3801
+
+properties:
+  compatible:
+    enum:
+      - ti,tps3801
+
+  reset-gpios:
+    maxItems: 1
+    description: Reference to the GPIO connected to the MR pin.
+
+  "#reset-cells":
+    const: 0
+
+required:
+  - compatible
+  - reset-gpios
+  - "#reset-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    reset: reset-controller {
+        compatible = "ti,tps3801";
+        #reset-cells = <0>;
+        reset-gpios = <&gpio3 2 GPIO_ACTIVE_LOW>;
+    };
+...