Re: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

Re: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Fabio Estevam]

Hi Anson,

On Mon, Sep 2, 2019 at 11:05 PM Anson Huang <Anson.Huang@nxp.com> wrote:

> +       ret = input_register_device(input);
> +       if (ret < 0) {
> +               dev_err(&pdev->dev, "failed to register input device\n");
> +               return ret;
> +       }
> +
> +       pdata->input = input;
> +       platform_set_drvdata(pdev, pdata);
> +
> +       ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, true);
> +       if (ret) {
> +               dev_warn(&pdev->dev, "enable scu group irq failed\n");
> +               return ret;

Better do a 'goto input_unregister' here instead and call
input_unregister_device().

RE: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Anson Huang]

Hi, Fabio

> On Mon, Sep 2, 2019 at 11:05 PM Anson Huang <Anson.Huang@nxp.com>
> wrote:
> 
> > +       ret = input_register_device(input);
> > +       if (ret < 0) {
> > +               dev_err(&pdev->dev, "failed to register input device\n");
> > +               return ret;
> > +       }
> > +
> > +       pdata->input = input;
> > +       platform_set_drvdata(pdev, pdata);
> > +
> > +       ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE,
> SC_IRQ_BUTTON, true);
> > +       if (ret) {
> > +               dev_warn(&pdev->dev, "enable scu group irq failed\n");
> > +               return ret;
> 
> Better do a 'goto input_unregister' here instead and call
> input_unregister_device().

Agreed, will fix in V3 later.

Thanks,
Anson.

Re: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Dmitry Torokhov]

On Mon, Sep 2, 2019 at 8:11 PM Anson Huang <anson.huang@nxp.com> wrote:
>
> Hi, Fabio
>
> > On Mon, Sep 2, 2019 at 11:05 PM Anson Huang <Anson.Huang@nxp.com>
> > wrote:
> >
> > > +       ret = input_register_device(input);
> > > +       if (ret < 0) {
> > > +               dev_err(&pdev->dev, "failed to register input device\n");
> > > +               return ret;
> > > +       }
> > > +
> > > +       pdata->input = input;
> > > +       platform_set_drvdata(pdev, pdata);
> > > +
> > > +       ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE,
> > SC_IRQ_BUTTON, true);
> > > +       if (ret) {
> > > +               dev_warn(&pdev->dev, "enable scu group irq failed\n");
> > > +               return ret;
> >
> > Better do a 'goto input_unregister' here instead and call
> > input_unregister_device().
>
> Agreed, will fix in V3 later.

Not needed actually as input device is managed by devm.

Thanks.

-- 
Dmitry

Re: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Oleksij Rempel]

Hi,

On 03.09.19 16:03, Anson Huang wrote:
> i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
> inside, the system controller is in charge of controlling power,
> clock and power key etc..
> 
> Adds i.MX system controller power key driver support, Linux kernel
> has to communicate with system controller via MU (message unit) IPC
> to get power key's status.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> ---
> Changes since V1:
> 	- remove "wakeup-source" property operation, scu power key uses generic scu irq,
> 	  no need to have this property for device wakeup operation.
> ---
>   drivers/input/keyboard/Kconfig         |   7 ++
>   drivers/input/keyboard/Makefile        |   1 +
>   drivers/input/keyboard/imx_sc_pwrkey.c | 169 +++++++++++++++++++++++++++++++++
>   3 files changed, 177 insertions(+)
>   create mode 100644 drivers/input/keyboard/imx_sc_pwrkey.c
> 
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 2e6d288..3aaeb9c 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -469,6 +469,13 @@ config KEYBOARD_IMX
>   	  To compile this driver as a module, choose M here: the
>   	  module will be called imx_keypad.
>   
> +config KEYBOARD_IMX_SC_PWRKEY
> +	tristate "IMX SCU Power Key Driver"
> +	depends on IMX_SCU
> +	help
> +	  This is the system controller powerkey driver for NXP i.MX SoCs with
> +	  system controller inside.

The KEY is configurable over devicetree, why is it called PWRKEY? It looks for me as 
generic SCU key handler.

>   config KEYBOARD_NEWTON
>   	tristate "Newton keyboard"
>   	select SERIO
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index 9510325..9ea5585 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -29,6 +29,7 @@ obj-$(CONFIG_KEYBOARD_HIL)		+= hil_kbd.o
>   obj-$(CONFIG_KEYBOARD_HIL_OLD)		+= hilkbd.o
>   obj-$(CONFIG_KEYBOARD_IPAQ_MICRO)	+= ipaq-micro-keys.o
>   obj-$(CONFIG_KEYBOARD_IMX)		+= imx_keypad.o
> +obj-$(CONFIG_KEYBOARD_IMX_SC_PWRKEY)	+= imx_sc_pwrkey.o
>   obj-$(CONFIG_KEYBOARD_HP6XX)		+= jornada680_kbd.o
>   obj-$(CONFIG_KEYBOARD_HP7XX)		+= jornada720_kbd.o
>   obj-$(CONFIG_KEYBOARD_LKKBD)		+= lkkbd.o
> diff --git a/drivers/input/keyboard/imx_sc_pwrkey.c b/drivers/input/keyboard/imx_sc_pwrkey.c
> new file mode 100644
> index 0000000..53aa9a4
> --- /dev/null
> +++ b/drivers/input/keyboard/imx_sc_pwrkey.c
> @@ -0,0 +1,169 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2019 NXP.
> + */
> +
> +#include <linux/device.h>
> +#include <linux/err.h>
> +#include <linux/firmware/imx/sci.h>
> +#include <linux/init.h>
> +#include <linux/input.h>
> +#include <linux/interrupt.h>
> +#include <linux/jiffies.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/platform_device.h>
> +
> +#define DEBOUNCE_TIME	100
> +#define REPEAT_INTERVAL	60
> +
> +#define SC_IRQ_BUTTON		1
> +#define SC_IRQ_GROUP_WAKE	3
> +#define IMX_SC_MISC_FUNC_GET_BUTTON_STATUS	18
> +
> +struct imx_pwrkey_drv_data {
> +	int keycode;
> +	bool keystate;  /* 1: pressed, 0: release */
> +	bool delay_check;
> +	struct delayed_work check_work;
> +	struct input_dev *input;
> +};
> +
> +struct imx_sc_msg_pwrkey {
> +	struct imx_sc_rpc_msg hdr;
> +	u8 state;
> +};
> +static struct imx_pwrkey_drv_data *pdata;

Why is it global struct? It seems to be flexible configurable over devicetree. So I would 
assume it should be able to handle more then one button. Please remove global variables, 
make it allocatable per OF node.

Please use different name "pdata" is usually used as platform data. Please, use "priv".

> +static struct imx_sc_ipc *pwrkey_ipc_handle;

same as before, no global variables.

> +
> +static int imx_sc_pwrkey_notify(struct notifier_block *nb,
> +				unsigned long event, void *group)
> +{
> +	if ((event & SC_IRQ_BUTTON) && (*(u8 *)group == SC_IRQ_GROUP_WAKE)
> +	    && !pdata->delay_check) {
> +		pdata->delay_check = 1;
> +		schedule_delayed_work(&pdata->check_work,
> +				      msecs_to_jiffies(REPEAT_INTERVAL));
> +	}
> +
> +	return 0;
> +}
> +
> +static void imx_sc_check_for_events(struct work_struct *work)
> +{
> +	struct input_dev *input = pdata->input;
> +	struct imx_sc_msg_pwrkey msg;
> +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
> +	bool state;
> +
> +	hdr->ver = IMX_SC_RPC_VERSION;
> +	hdr->svc = IMX_SC_RPC_SVC_MISC;
> +	hdr->func = IMX_SC_MISC_FUNC_GET_BUTTON_STATUS;
> +	hdr->size = 1;
> +
> +	/*
> +	 * Current SCU firmware does NOT have return value for
> +	 * this API, that means it is always successful.
> +	 */

It is not true for the kernel part:
https://elixir.bootlin.com/linux/latest/source/drivers/firmware/imx/imx-scu.c#L157

imx_scu_call_rpc() may fail in different ways and provide proper error value. Please use it.

> +	imx_scu_call_rpc(pwrkey_ipc_handle, &msg, true); > +	state = msg.state;

the conversation u8 to bool should be done here.

> +
> +	if (!state && !pdata->keystate)
> +		state = true;
> +
> +	if (state ^ pdata->keystate) {
> +		pm_wakeup_event(input->dev.parent, 0);
> +		pdata->keystate = !!state;

		the state is already bool. Why do you need extra conversations?

> +		input_event(input, EV_KEY, pdata->keycode, !!state);

same here.

> +		input_sync(input);
> +		if (!state)
> +			pdata->delay_check = 0;
> +		pm_relax(pdata->input->dev.parent);
> +	}
> +
> +	if (state)
> +		schedule_delayed_work(&pdata->check_work,
> +				      msecs_to_jiffies(DEBOUNCE_TIME));
> +}
> +
> +static struct notifier_block imx_sc_pwrkey_notifier = {
> +	.notifier_call = imx_sc_pwrkey_notify,
> +};
> +
> +static int imx_sc_pwrkey_probe(struct platform_device *pdev)
> +{
> +	struct device_node *np = pdev->dev.of_node;
> +	struct input_dev *input;
> +	int ret;
> +
> +	ret = imx_scu_get_handle(&pwrkey_ipc_handle);
> +	if (ret)
> +		return ret;
> +
> +	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> +	if (!pdata)
> +		return -ENOMEM;
> +
> +	if (of_property_read_u32(np, "linux,keycode", &pdata->keycode) > +		pdata->keycode = KEY_POWER;

According binding documentation, linux,keycode is requered parameter, in this case you 
should fail if it is not set.

> +		dev_warn(&pdev->dev, "KEY_POWER without setting in dts\n");
> +	}
> +
> +	INIT_DELAYED_WORK(&pdata->check_work, imx_sc_check_for_events);
> +
> +	input = devm_input_allocate_device(&pdev->dev);
> +	if (!input) {
> +		dev_err(&pdev->dev, "failed to allocate the input device\n");
> +		return -ENOMEM;
> +	}
> +
> +	input->name = pdev->name;
> +	input->phys = "imx-sc-pwrkey/input0";
> +	input->id.bustype = BUS_HOST;
> +
> +	input_set_capability(input, EV_KEY, pdata->keycode);
> +
> +	ret = input_register_device(input);
> +	if (ret < 0) {
> +		dev_err(&pdev->dev, "failed to register input device\n");
> +		return ret;
> +	}
> +
> +	pdata->input = input;
> +	platform_set_drvdata(pdev, pdata);
> +
> +	ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, true);
> +	if (ret) {
> +		dev_warn(&pdev->dev, "enable scu group irq failed\n");
> +		return ret;
> +	}
> +
> +	ret = imx_scu_irq_register_notifier(&imx_sc_pwrkey_notifier);
> +	if (ret) {
> +		imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, false);
> +		dev_warn(&pdev->dev, "register scu notifier failed\n");
> +	}
> +
> +	return ret;
> +}
> +
> +static const struct of_device_id imx_sc_pwrkey_ids[] = {
> +	{ .compatible = "fsl,imx-sc-pwrkey" },
> +	{ /* sentinel */ }
> +};
> +MODULE_DEVICE_TABLE(of, imx_sc_pwrkey_ids);
> +
> +static struct platform_driver imx_sc_pwrkey_driver = {
> +	.driver = {
> +		.name = "imx-sc-pwrkey",
> +		.of_match_table = imx_sc_pwrkey_ids,
> +	},
> +	.probe = imx_sc_pwrkey_probe,
> +};
> +module_platform_driver(imx_sc_pwrkey_driver);
> +
> +MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
> +MODULE_DESCRIPTION("i.MX System Controller Power Key Driver");
> +MODULE_LICENSE("GPL v2");
> 

Kind regards,
Oleksij Rempel

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Oleksij Rempel]

On 03.09.19 16:03, Anson Huang wrote:
> NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as
> system controller, the system controller is in charge of system
> power, clock and power key event etc. management, Linux kernel
> has to communicate with system controller via MU (message unit)
> IPC to get power key event, add binding doc for i.MX system
> controller power key driver.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> ---
> Changes since V1:
> 	- remove "wakeup-source" property, as it is NOT needed for SCU interrupt;
> 	- remove "status" in example.
> ---
>   .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14 ++++++++++++++
>   1 file changed, 14 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> index c149fad..f93e2e4 100644
> --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> @@ -157,6 +157,15 @@ Required properties:
>   Optional properties:
>   - timeout-sec: contains the watchdog timeout in seconds.
>   
> +Power key bindings based on SCU Message Protocol
> +------------------------------------------------------------
> +
> +Required properties:
> +- compatible: should be:
> +              "fsl,imx8qxp-sc-pwrkey"
> +              followed by "fsl,imx-sc-pwrkey";
> +- linux,keycodes: See Documentation/devicetree/bindings/input/keys.txt

linux,keycodes is required parameter. So, this kay cab be anything. Why the compatible is 
called pwrkey? Probably it is better to call it "*-sc-key"

> +
>   Example (imx8qxp):
>   -------------
>   aliases {
> @@ -220,6 +229,11 @@ firmware {
>   			compatible = "fsl,imx8qxp-sc-rtc";
>   		};
>   
> +		scu_pwrkey: scu-pwrkey {
> +			compatible = "fsl,imx8qxp-sc-pwrkey", "fsl,imx-sc-pwrkey";
> +			linux,keycode = <KEY_POWER>;
> +		};
> +
>   		watchdog {
>   			compatible = "fsl,imx8qxp-sc-wdt", "fsl,imx-sc-wdt";
>   			timeout-sec = <60>;
> 

Kind regards,
Oleksij Rempel

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

RE: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Anson Huang]

Hi, Oleksij

> On 03.09.19 16:03, Anson Huang wrote:
> > NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
> > controller, the system controller is in charge of system power, clock
> > and power key event etc. management, Linux kernel has to communicate
> > with system controller via MU (message unit) IPC to get power key
> > event, add binding doc for i.MX system controller power key driver.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > ---
> > Changes since V1:
> > 	- remove "wakeup-source" property, as it is NOT needed for SCU
> interrupt;
> > 	- remove "status" in example.
> > ---
> >   .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14
> ++++++++++++++
> >   1 file changed, 14 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > index c149fad..f93e2e4 100644
> > --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > @@ -157,6 +157,15 @@ Required properties:
> >   Optional properties:
> >   - timeout-sec: contains the watchdog timeout in seconds.
> >
> > +Power key bindings based on SCU Message Protocol
> > +------------------------------------------------------------
> > +
> > +Required properties:
> > +- compatible: should be:
> > +              "fsl,imx8qxp-sc-pwrkey"
> > +              followed by "fsl,imx-sc-pwrkey";
> > +- linux,keycodes: See
> > +Documentation/devicetree/bindings/input/keys.txt
> 
> linux,keycodes is required parameter. So, this kay cab be anything. Why the
> compatible is called pwrkey? Probably it is better to call it "*-sc-key"

This key is kind of special, it is ON/OFF button which is designed for power key
purpose, it has HW function such as long pressing it would shutdown the system power,
so we always use it as power key, NOT general key, does it make sense?

Thanks,
Anson.

Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Oleksij Rempel]

On 03.09.19 08:37, Anson Huang wrote:
> Hi, Oleksij
> 
>> On 03.09.19 16:03, Anson Huang wrote:
>>> NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
>>> controller, the system controller is in charge of system power, clock
>>> and power key event etc. management, Linux kernel has to communicate
>>> with system controller via MU (message unit) IPC to get power key
>>> event, add binding doc for i.MX system controller power key driver.
>>>
>>> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
>>> ---
>>> Changes since V1:
>>> 	- remove "wakeup-source" property, as it is NOT needed for SCU
>> interrupt;
>>> 	- remove "status" in example.
>>> ---
>>>    .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14
>> ++++++++++++++
>>>    1 file changed, 14 insertions(+)
>>>
>>> diff --git
>>> a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
>>> b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
>>> index c149fad..f93e2e4 100644
>>> --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
>>> +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
>>> @@ -157,6 +157,15 @@ Required properties:
>>>    Optional properties:
>>>    - timeout-sec: contains the watchdog timeout in seconds.
>>>
>>> +Power key bindings based on SCU Message Protocol
>>> +------------------------------------------------------------
>>> +
>>> +Required properties:
>>> +- compatible: should be:
>>> +              "fsl,imx8qxp-sc-pwrkey"
>>> +              followed by "fsl,imx-sc-pwrkey";
>>> +- linux,keycodes: See
>>> +Documentation/devicetree/bindings/input/keys.txt
>>
>> linux,keycodes is required parameter. So, this kay cab be anything. Why the
>> compatible is called pwrkey? Probably it is better to call it "*-sc-key"
> 
> This key is kind of special, it is ON/OFF button which is designed for power key
> purpose, it has HW function such as long pressing it would shutdown the system power,
> so we always use it as power key, NOT general key, does it make sense?

I assume, OF devs will argue: DT is describing hardware not software.
On other hand, software will get notification about assertion/deassertion of this key. So, 
it is just normal key. If, for some reason, it will trigger world destruction, if it is 
pressed too long... probably no body cares.
You can provide fsl,imx-sc-key as additional compatible. In case linux will need some 
quirks, we still can fall back to more precise compatible "fsl,imx8qxp-sc-pwrkey".

Kind regards,
Oleksij Rempel

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

RE: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Anson Huang]

Hi, Oleksij

> On 03.09.19 16:03, Anson Huang wrote:
> > i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
> > inside, the system controller is in charge of controlling power, clock
> > and power key etc..
> >
> > Adds i.MX system controller power key driver support, Linux kernel has
> > to communicate with system controller via MU (message unit) IPC to get
> > power key's status.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > ---
> > Changes since V1:
> > 	- remove "wakeup-source" property operation, scu power key uses
> generic scu irq,
> > 	  no need to have this property for device wakeup operation.
> > ---
> >   drivers/input/keyboard/Kconfig         |   7 ++
> >   drivers/input/keyboard/Makefile        |   1 +
> >   drivers/input/keyboard/imx_sc_pwrkey.c | 169
> +++++++++++++++++++++++++++++++++
> >   3 files changed, 177 insertions(+)
> >   create mode 100644 drivers/input/keyboard/imx_sc_pwrkey.c
> >
> > diff --git a/drivers/input/keyboard/Kconfig
> > b/drivers/input/keyboard/Kconfig index 2e6d288..3aaeb9c 100644
> > --- a/drivers/input/keyboard/Kconfig
> > +++ b/drivers/input/keyboard/Kconfig
> > @@ -469,6 +469,13 @@ config KEYBOARD_IMX
> >   	  To compile this driver as a module, choose M here: the
> >   	  module will be called imx_keypad.
> >
> > +config KEYBOARD_IMX_SC_PWRKEY
> > +	tristate "IMX SCU Power Key Driver"
> > +	depends on IMX_SCU
> > +	help
> > +	  This is the system controller powerkey driver for NXP i.MX SoCs with
> > +	  system controller inside.
> 
> The KEY is configurable over devicetree, why is it called PWRKEY? It looks for
> me as generic SCU key handler.

We always use it as power key, NOT a generic key, as it has HW function designed
for power key purpose. 

> 
> >   config KEYBOARD_NEWTON
> >   	tristate "Newton keyboard"
> >   	select SERIO
> > diff --git a/drivers/input/keyboard/Makefile
> > b/drivers/input/keyboard/Makefile index 9510325..9ea5585 100644
> > --- a/drivers/input/keyboard/Makefile
> > +++ b/drivers/input/keyboard/Makefile
> > @@ -29,6 +29,7 @@ obj-$(CONFIG_KEYBOARD_HIL)		+= hil_kbd.o
> >   obj-$(CONFIG_KEYBOARD_HIL_OLD)		+= hilkbd.o
> >   obj-$(CONFIG_KEYBOARD_IPAQ_MICRO)	+= ipaq-micro-keys.o
> >   obj-$(CONFIG_KEYBOARD_IMX)		+= imx_keypad.o
> > +obj-$(CONFIG_KEYBOARD_IMX_SC_PWRKEY)	+= imx_sc_pwrkey.o
> >   obj-$(CONFIG_KEYBOARD_HP6XX)		+= jornada680_kbd.o
> >   obj-$(CONFIG_KEYBOARD_HP7XX)		+= jornada720_kbd.o
> >   obj-$(CONFIG_KEYBOARD_LKKBD)		+= lkkbd.o
> > diff --git a/drivers/input/keyboard/imx_sc_pwrkey.c
> > b/drivers/input/keyboard/imx_sc_pwrkey.c
> > new file mode 100644
> > index 0000000..53aa9a4
> > --- /dev/null
> > +++ b/drivers/input/keyboard/imx_sc_pwrkey.c
> > @@ -0,0 +1,169 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Copyright 2019 NXP.
> > + */
> > +
> > +#include <linux/device.h>
> > +#include <linux/err.h>
> > +#include <linux/firmware/imx/sci.h>
> > +#include <linux/init.h>
> > +#include <linux/input.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/jiffies.h>
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/of_address.h>
> > +#include <linux/platform_device.h>
> > +
> > +#define DEBOUNCE_TIME	100
> > +#define REPEAT_INTERVAL	60
> > +
> > +#define SC_IRQ_BUTTON		1
> > +#define SC_IRQ_GROUP_WAKE	3
> > +#define IMX_SC_MISC_FUNC_GET_BUTTON_STATUS	18
> > +
> > +struct imx_pwrkey_drv_data {
> > +	int keycode;
> > +	bool keystate;  /* 1: pressed, 0: release */
> > +	bool delay_check;
> > +	struct delayed_work check_work;
> > +	struct input_dev *input;
> > +};
> > +
> > +struct imx_sc_msg_pwrkey {
> > +	struct imx_sc_rpc_msg hdr;
> > +	u8 state;
> > +};
> > +static struct imx_pwrkey_drv_data *pdata;
> 
> Why is it global struct? It seems to be flexible configurable over devicetree.
> So I would assume it should be able to handle more then one button. Please
> remove global variables, make it allocatable per OF node.

There is ONLY one button available for SC key, but yes, I think I can make the structure
private and get all necessary data from the structure using container_of.

> 
> Please use different name "pdata" is usually used as platform data. Please,
> use "priv".

OK.

> 
> > +static struct imx_sc_ipc *pwrkey_ipc_handle;
> 
> same as before, no global variables.

Will move it into private platform data structure.

> 
> > +
> > +static int imx_sc_pwrkey_notify(struct notifier_block *nb,
> > +				unsigned long event, void *group) {
> > +	if ((event & SC_IRQ_BUTTON) && (*(u8 *)group ==
> SC_IRQ_GROUP_WAKE)
> > +	    && !pdata->delay_check) {
> > +		pdata->delay_check = 1;
> > +		schedule_delayed_work(&pdata->check_work,
> > +				      msecs_to_jiffies(REPEAT_INTERVAL));
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> > +static void imx_sc_check_for_events(struct work_struct *work) {
> > +	struct input_dev *input = pdata->input;
> > +	struct imx_sc_msg_pwrkey msg;
> > +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
> > +	bool state;
> > +
> > +	hdr->ver = IMX_SC_RPC_VERSION;
> > +	hdr->svc = IMX_SC_RPC_SVC_MISC;
> > +	hdr->func = IMX_SC_MISC_FUNC_GET_BUTTON_STATUS;
> > +	hdr->size = 1;
> > +
> > +	/*
> > +	 * Current SCU firmware does NOT have return value for
> > +	 * this API, that means it is always successful.
> > +	 */
> 
> It is not true for the kernel part:
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Felixir.
> bootlin.com%2Flinux%2Flatest%2Fsource%2Fdrivers%2Ffirmware%2Fimx%2F
> imx-
> scu.c%23L157&amp;data=02%7C01%7Canson.huang%40nxp.com%7C7a5ed3
> ef3b2541e61be808d7303810a9%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C
> 0%7C0%7C637030889669489141&amp;sdata=d3uw6x6WCPeavJu3QYf9o9cxx
> Rx4mJar04fQFLF9EhE%3D&amp;reserved=0
> 
> imx_scu_call_rpc() may fail in different ways and provide proper error value.
> Please use it.

There are about 3 APIs are special, this API is one of them, this API has no return value
from SCU FW API, but it has response data from it, so that means if we set the response
to false, the stack will be free and mailbox will have NULL pointer issue when response 
data passed from SCU FW. If we set the response to true, as the SCU FW has no return value,
the return value will be the msg->func which will be already failed, that is why we have to skip
the return value check. This is one restriction/bug of SCU FW, we will notify SCU FW owner to
fix/improve.


> 
> > +	imx_scu_call_rpc(pwrkey_ipc_handle, &msg, true); > +	state =
> msg.state;
> 
> the conversation u8 to bool should be done here.

OK.

> 
> > +
> > +	if (!state && !pdata->keystate)
> > +		state = true;
> > +
> > +	if (state ^ pdata->keystate) {
> > +		pm_wakeup_event(input->dev.parent, 0);
> > +		pdata->keystate = !!state;
> 
> 		the state is already bool. Why do you need extra
> conversations?

Will remove it.

> 
> > +		input_event(input, EV_KEY, pdata->keycode, !!state);
> 
> same here.

Will remove it.

> 
> > +		input_sync(input);
> > +		if (!state)
> > +			pdata->delay_check = 0;
> > +		pm_relax(pdata->input->dev.parent);
> > +	}
> > +
> > +	if (state)
> > +		schedule_delayed_work(&pdata->check_work,
> > +				      msecs_to_jiffies(DEBOUNCE_TIME)); }
> > +
> > +static struct notifier_block imx_sc_pwrkey_notifier = {
> > +	.notifier_call = imx_sc_pwrkey_notify, };
> > +
> > +static int imx_sc_pwrkey_probe(struct platform_device *pdev) {
> > +	struct device_node *np = pdev->dev.of_node;
> > +	struct input_dev *input;
> > +	int ret;
> > +
> > +	ret = imx_scu_get_handle(&pwrkey_ipc_handle);
> > +	if (ret)
> > +		return ret;
> > +
> > +	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
> > +	if (!pdata)
> > +		return -ENOMEM;
> > +
> > +	if (of_property_read_u32(np, "linux,keycode", &pdata->keycode) > +
> 		pdata->keycode = KEY_POWER;
> 
> According binding documentation, linux,keycode is requered parameter, in
> this case you should fail if it is not set.

Agreed, will add it in V3.

Thanks,
Anson.

RE: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Anson Huang]

Hi, Oleksij

> On 03.09.19 08:37, Anson Huang wrote:
> > Hi, Oleksij
> >
> >> On 03.09.19 16:03, Anson Huang wrote:
> >>> NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
> >>> controller, the system controller is in charge of system power,
> >>> clock and power key event etc. management, Linux kernel has to
> >>> communicate with system controller via MU (message unit) IPC to get
> >>> power key event, add binding doc for i.MX system controller power key
> driver.
> >>>
> >>> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> >>> ---
> >>> Changes since V1:
> >>> 	- remove "wakeup-source" property, as it is NOT needed for SCU
> >> interrupt;
> >>> 	- remove "status" in example.
> >>> ---
> >>>    .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14
> >> ++++++++++++++
> >>>    1 file changed, 14 insertions(+)
> >>>
> >>> diff --git
> >>> a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> >>> b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> >>> index c149fad..f93e2e4 100644
> >>> --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> >>> +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> >>> @@ -157,6 +157,15 @@ Required properties:
> >>>    Optional properties:
> >>>    - timeout-sec: contains the watchdog timeout in seconds.
> >>>
> >>> +Power key bindings based on SCU Message Protocol
> >>> +------------------------------------------------------------
> >>> +
> >>> +Required properties:
> >>> +- compatible: should be:
> >>> +              "fsl,imx8qxp-sc-pwrkey"
> >>> +              followed by "fsl,imx-sc-pwrkey";
> >>> +- linux,keycodes: See
> >>> +Documentation/devicetree/bindings/input/keys.txt
> >>
> >> linux,keycodes is required parameter. So, this kay cab be anything.
> >> Why the compatible is called pwrkey? Probably it is better to call it "*-sc-
> key"
> >
> > This key is kind of special, it is ON/OFF button which is designed for
> > power key purpose, it has HW function such as long pressing it would
> > shutdown the system power, so we always use it as power key, NOT
> general key, does it make sense?
> 
> I assume, OF devs will argue: DT is describing hardware not software.
> On other hand, software will get notification about assertion/deassertion of
> this key. So, it is just normal key. If, for some reason, it will trigger world
> destruction, if it is pressed too long... probably no body cares.
> You can provide fsl,imx-sc-key as additional compatible. In case linux will
> need some quirks, we still can fall back to more precise compatible
> "fsl,imx8qxp-sc-pwrkey".

I am OK with that, so I will use "fsl,imx-sc-key" as additional compatible and also
present in driver. 

Anson.

Re: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Oleksij Rempel]

On 03.09.19 08:48, Anson Huang wrote:
> Hi, Oleksij
> 
>> On 03.09.19 16:03, Anson Huang wrote:
>>> i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
>>> inside, the system controller is in charge of controlling power, clock
>>> and power key etc..
>>>
>>> Adds i.MX system controller power key driver support, Linux kernel has
>>> to communicate with system controller via MU (message unit) IPC to get
>>> power key's status.
>>>
>>> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
>>> ---
>>> Changes since V1:
>>> 	- remove "wakeup-source" property operation, scu power key uses
>> generic scu irq,
>>> 	  no need to have this property for device wakeup operation.
>>> ---
>>>    drivers/input/keyboard/Kconfig         |   7 ++
>>>    drivers/input/keyboard/Makefile        |   1 +
>>>    drivers/input/keyboard/imx_sc_pwrkey.c | 169
>> +++++++++++++++++++++++++++++++++
>>>    3 files changed, 177 insertions(+)
>>>    create mode 100644 drivers/input/keyboard/imx_sc_pwrkey.c
>>>
>>> diff --git a/drivers/input/keyboard/Kconfig
>>> b/drivers/input/keyboard/Kconfig index 2e6d288..3aaeb9c 100644
>>> --- a/drivers/input/keyboard/Kconfig
>>> +++ b/drivers/input/keyboard/Kconfig
>>> @@ -469,6 +469,13 @@ config KEYBOARD_IMX
>>>    	  To compile this driver as a module, choose M here: the
>>>    	  module will be called imx_keypad.
>>>
>>> +config KEYBOARD_IMX_SC_PWRKEY
>>> +	tristate "IMX SCU Power Key Driver"
>>> +	depends on IMX_SCU
>>> +	help
>>> +	  This is the system controller powerkey driver for NXP i.MX SoCs with
>>> +	  system controller inside.
>>
>> The KEY is configurable over devicetree, why is it called PWRKEY? It looks for
>> me as generic SCU key handler.
> 
> We always use it as power key, NOT a generic key, as it has HW function designed
> for power key purpose.

gpio-key driver is mostly used for power or reboot key. And it is still called gpio-key 
driver. If it is used for power key only, why is it configurable? I can configure it as 
KEY_ENTER or some thing different. This driver has not KEY_POWER specific any thing.

> 
>>
>>>    config KEYBOARD_NEWTON
>>>    	tristate "Newton keyboard"
>>>    	select SERIO
>>> diff --git a/drivers/input/keyboard/Makefile
>>> b/drivers/input/keyboard/Makefile index 9510325..9ea5585 100644
>>> --- a/drivers/input/keyboard/Makefile
>>> +++ b/drivers/input/keyboard/Makefile
>>> @@ -29,6 +29,7 @@ obj-$(CONFIG_KEYBOARD_HIL)		+= hil_kbd.o
>>>    obj-$(CONFIG_KEYBOARD_HIL_OLD)		+= hilkbd.o
>>>    obj-$(CONFIG_KEYBOARD_IPAQ_MICRO)	+= ipaq-micro-keys.o
>>>    obj-$(CONFIG_KEYBOARD_IMX)		+= imx_keypad.o
>>> +obj-$(CONFIG_KEYBOARD_IMX_SC_PWRKEY)	+= imx_sc_pwrkey.o
>>>    obj-$(CONFIG_KEYBOARD_HP6XX)		+= jornada680_kbd.o
>>>    obj-$(CONFIG_KEYBOARD_HP7XX)		+= jornada720_kbd.o
>>>    obj-$(CONFIG_KEYBOARD_LKKBD)		+= lkkbd.o
>>> diff --git a/drivers/input/keyboard/imx_sc_pwrkey.c
>>> b/drivers/input/keyboard/imx_sc_pwrkey.c
>>> new file mode 100644
>>> index 0000000..53aa9a4
>>> --- /dev/null
>>> +++ b/drivers/input/keyboard/imx_sc_pwrkey.c
>>> @@ -0,0 +1,169 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/*
>>> + * Copyright 2019 NXP.
>>> + */
>>> +
>>> +#include <linux/device.h>
>>> +#include <linux/err.h>
>>> +#include <linux/firmware/imx/sci.h>
>>> +#include <linux/init.h>
>>> +#include <linux/input.h>
>>> +#include <linux/interrupt.h>
>>> +#include <linux/jiffies.h>
>>> +#include <linux/kernel.h>
>>> +#include <linux/module.h>
>>> +#include <linux/of.h>
>>> +#include <linux/of_address.h>
>>> +#include <linux/platform_device.h>
>>> +
>>> +#define DEBOUNCE_TIME	100
>>> +#define REPEAT_INTERVAL	60
>>> +
>>> +#define SC_IRQ_BUTTON		1
>>> +#define SC_IRQ_GROUP_WAKE	3
>>> +#define IMX_SC_MISC_FUNC_GET_BUTTON_STATUS	18
>>> +
>>> +struct imx_pwrkey_drv_data {
>>> +	int keycode;
>>> +	bool keystate;  /* 1: pressed, 0: release */
>>> +	bool delay_check;
>>> +	struct delayed_work check_work;
>>> +	struct input_dev *input;
>>> +};
>>> +
>>> +struct imx_sc_msg_pwrkey {
>>> +	struct imx_sc_rpc_msg hdr;
>>> +	u8 state;
>>> +};
>>> +static struct imx_pwrkey_drv_data *pdata;
>>
>> Why is it global struct? It seems to be flexible configurable over devicetree.
>> So I would assume it should be able to handle more then one button. Please
>> remove global variables, make it allocatable per OF node.
> 
> There is ONLY one button available for SC key, but yes, I think I can make the structure
> private and get all necessary data from the structure using container_of.

And we will never need more then 640 kB RAM ;)
https://en.wikiquote.org/wiki/Talk:Bill_Gates

> 
>>
>> Please use different name "pdata" is usually used as platform data. Please,
>> use "priv".
> 
> OK.
> 
>>
>>> +static struct imx_sc_ipc *pwrkey_ipc_handle;
>>
>> same as before, no global variables.
> 
> Will move it into private platform data structure.
> 
>>
>>> +
>>> +static int imx_sc_pwrkey_notify(struct notifier_block *nb,
>>> +				unsigned long event, void *group) {
>>> +	if ((event & SC_IRQ_BUTTON) && (*(u8 *)group ==
>> SC_IRQ_GROUP_WAKE)
>>> +	    && !pdata->delay_check) {
>>> +		pdata->delay_check = 1;
>>> +		schedule_delayed_work(&pdata->check_work,
>>> +				      msecs_to_jiffies(REPEAT_INTERVAL));
>>> +	}
>>> +
>>> +	return 0;
>>> +}
>>> +
>>> +static void imx_sc_check_for_events(struct work_struct *work) {
>>> +	struct input_dev *input = pdata->input;
>>> +	struct imx_sc_msg_pwrkey msg;
>>> +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
>>> +	bool state;
>>> +
>>> +	hdr->ver = IMX_SC_RPC_VERSION;
>>> +	hdr->svc = IMX_SC_RPC_SVC_MISC;
>>> +	hdr->func = IMX_SC_MISC_FUNC_GET_BUTTON_STATUS;
>>> +	hdr->size = 1;
>>> +
>>> +	/*
>>> +	 * Current SCU firmware does NOT have return value for
>>> +	 * this API, that means it is always successful.
>>> +	 */
>>
>> It is not true for the kernel part:
>> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Felixir.
>> bootlin.com%2Flinux%2Flatest%2Fsource%2Fdrivers%2Ffirmware%2Fimx%2F
>> imx-
>> scu.c%23L157&amp;data=02%7C01%7Canson.huang%40nxp.com%7C7a5ed3
>> ef3b2541e61be808d7303810a9%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C
>> 0%7C0%7C637030889669489141&amp;sdata=d3uw6x6WCPeavJu3QYf9o9cxx
>> Rx4mJar04fQFLF9EhE%3D&amp;reserved=0
>>
>> imx_scu_call_rpc() may fail in different ways and provide proper error value.
>> Please use it.
> 
> There are about 3 APIs are special, this API is one of them, this API has no return value
> from SCU FW API, but it has response data from it, so that means if we set the response
> to false, the stack will be free and mailbox will have NULL pointer issue when response
> data passed from SCU FW. If we set the response to true, as the SCU FW has no return value,
> the return value will be the msg->func which will be already failed, that is why we have to skip
> the return value check. This is one restriction/bug of SCU FW, we will notify SCU FW owner to
> fix/improve.

Ok, I see. imx_scu_call_rpc() can return kernel side errors, for example from imx-scu.c 
framework EINVAL or ETIMEDOUT or what ever error mbox framework may also provide. 
Aaaannnndd... it can extract an error from SCU package and return it over same way as 
other errors.

And current SCU version has some bugs, so it is providing wrong error value. Soo... as 
usual the NXP has decided to make the linux kernel a bit more worse to make the SCU 
firmware happy? Is it what you trying to describe? Really ?! :D

Please. Fix the SCU first. The provide fixed kernel patch.

>>
>>> +	imx_scu_call_rpc(pwrkey_ipc_handle, &msg, true); > +	state =
>> msg.state;
>>
>> the conversation u8 to bool should be done here.
> 
> OK.
> 
>>
>>> +
>>> +	if (!state && !pdata->keystate)
>>> +		state = true;
>>> +
>>> +	if (state ^ pdata->keystate) {
>>> +		pm_wakeup_event(input->dev.parent, 0);
>>> +		pdata->keystate = !!state;
>>
>> 		the state is already bool. Why do you need extra
>> conversations?
> 
> Will remove it.
> 
>>
>>> +		input_event(input, EV_KEY, pdata->keycode, !!state);
>>
>> same here.
> 
> Will remove it.
> 
>>
>>> +		input_sync(input);
>>> +		if (!state)
>>> +			pdata->delay_check = 0;
>>> +		pm_relax(pdata->input->dev.parent);
>>> +	}
>>> +
>>> +	if (state)
>>> +		schedule_delayed_work(&pdata->check_work,
>>> +				      msecs_to_jiffies(DEBOUNCE_TIME)); }
>>> +
>>> +static struct notifier_block imx_sc_pwrkey_notifier = {
>>> +	.notifier_call = imx_sc_pwrkey_notify, };
>>> +
>>> +static int imx_sc_pwrkey_probe(struct platform_device *pdev) {
>>> +	struct device_node *np = pdev->dev.of_node;
>>> +	struct input_dev *input;
>>> +	int ret;
>>> +
>>> +	ret = imx_scu_get_handle(&pwrkey_ipc_handle);
>>> +	if (ret)
>>> +		return ret;
>>> +
>>> +	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
>>> +	if (!pdata)
>>> +		return -ENOMEM;
>>> +
>>> +	if (of_property_read_u32(np, "linux,keycode", &pdata->keycode) > +
>> 		pdata->keycode = KEY_POWER;
>>
>> According binding documentation, linux,keycode is requered parameter, in
>> this case you should fail if it is not set.
> 
> Agreed, will add it in V3.
> 
> Thanks,
> Anson.
> 

Kind regards,
Oleksij Rempel

-- 
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RE: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Anson Huang]

Hi, Oleksij

> On 03.09.19 08:48, Anson Huang wrote:
> > Hi, Oleksij
> >
> >> On 03.09.19 16:03, Anson Huang wrote:
> >>> i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
> >>> inside, the system controller is in charge of controlling power,
> >>> clock and power key etc..
> >>>
> >>> Adds i.MX system controller power key driver support, Linux kernel
> >>> has to communicate with system controller via MU (message unit) IPC
> >>> to get power key's status.
> >>>
> >>> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> >>> ---
> >>> Changes since V1:
> >>> 	- remove "wakeup-source" property operation, scu power key uses
> >> generic scu irq,
> >>> 	  no need to have this property for device wakeup operation.
> >>> ---
> >>>    drivers/input/keyboard/Kconfig         |   7 ++
> >>>    drivers/input/keyboard/Makefile        |   1 +
> >>>    drivers/input/keyboard/imx_sc_pwrkey.c | 169
> >> +++++++++++++++++++++++++++++++++
> >>>    3 files changed, 177 insertions(+)
> >>>    create mode 100644 drivers/input/keyboard/imx_sc_pwrkey.c
> >>>
> >>> diff --git a/drivers/input/keyboard/Kconfig
> >>> b/drivers/input/keyboard/Kconfig index 2e6d288..3aaeb9c 100644
> >>> --- a/drivers/input/keyboard/Kconfig
> >>> +++ b/drivers/input/keyboard/Kconfig
> >>> @@ -469,6 +469,13 @@ config KEYBOARD_IMX
> >>>    	  To compile this driver as a module, choose M here: the
> >>>    	  module will be called imx_keypad.
> >>>
> >>> +config KEYBOARD_IMX_SC_PWRKEY
> >>> +	tristate "IMX SCU Power Key Driver"
> >>> +	depends on IMX_SCU
> >>> +	help
> >>> +	  This is the system controller powerkey driver for NXP i.MX SoCs with
> >>> +	  system controller inside.
> >>
> >> The KEY is configurable over devicetree, why is it called PWRKEY? It
> >> looks for me as generic SCU key handler.
> >
> > We always use it as power key, NOT a generic key, as it has HW
> > function designed for power key purpose.
> 
> gpio-key driver is mostly used for power or reboot key. And it is still called
> gpio-key driver. If it is used for power key only, why is it configurable? I can
> configure it as KEY_ENTER or some thing different. This driver has not
> KEY_POWER specific any thing.

Understood, I am making the V3 with all "power" removed, just using the "key".

> 
> >
> >>
> >>>    config KEYBOARD_NEWTON
> >>>    	tristate "Newton keyboard"
> >>>    	select SERIO
> >>> diff --git a/drivers/input/keyboard/Makefile
> >>> b/drivers/input/keyboard/Makefile index 9510325..9ea5585 100644
> >>> --- a/drivers/input/keyboard/Makefile
> >>> +++ b/drivers/input/keyboard/Makefile
> >>> @@ -29,6 +29,7 @@ obj-$(CONFIG_KEYBOARD_HIL)		+=
> hil_kbd.o
> >>>    obj-$(CONFIG_KEYBOARD_HIL_OLD)		+= hilkbd.o
> >>>    obj-$(CONFIG_KEYBOARD_IPAQ_MICRO)	+= ipaq-micro-keys.o
> >>>    obj-$(CONFIG_KEYBOARD_IMX)		+= imx_keypad.o
> >>> +obj-$(CONFIG_KEYBOARD_IMX_SC_PWRKEY)	+= imx_sc_pwrkey.o
> >>>    obj-$(CONFIG_KEYBOARD_HP6XX)		+= jornada680_kbd.o
> >>>    obj-$(CONFIG_KEYBOARD_HP7XX)		+= jornada720_kbd.o
> >>>    obj-$(CONFIG_KEYBOARD_LKKBD)		+= lkkbd.o
> >>> diff --git a/drivers/input/keyboard/imx_sc_pwrkey.c
> >>> b/drivers/input/keyboard/imx_sc_pwrkey.c
> >>> new file mode 100644
> >>> index 0000000..53aa9a4
> >>> --- /dev/null
> >>> +++ b/drivers/input/keyboard/imx_sc_pwrkey.c
> >>> @@ -0,0 +1,169 @@
> >>> +// SPDX-License-Identifier: GPL-2.0
> >>> +/*
> >>> + * Copyright 2019 NXP.
> >>> + */
> >>> +
> >>> +#include <linux/device.h>
> >>> +#include <linux/err.h>
> >>> +#include <linux/firmware/imx/sci.h> #include <linux/init.h>
> >>> +#include <linux/input.h> #include <linux/interrupt.h> #include
> >>> +<linux/jiffies.h> #include <linux/kernel.h> #include
> >>> +<linux/module.h> #include <linux/of.h> #include
> >>> +<linux/of_address.h> #include <linux/platform_device.h>
> >>> +
> >>> +#define DEBOUNCE_TIME	100
> >>> +#define REPEAT_INTERVAL	60
> >>> +
> >>> +#define SC_IRQ_BUTTON		1
> >>> +#define SC_IRQ_GROUP_WAKE	3
> >>> +#define IMX_SC_MISC_FUNC_GET_BUTTON_STATUS	18
> >>> +
> >>> +struct imx_pwrkey_drv_data {
> >>> +	int keycode;
> >>> +	bool keystate;  /* 1: pressed, 0: release */
> >>> +	bool delay_check;
> >>> +	struct delayed_work check_work;
> >>> +	struct input_dev *input;
> >>> +};
> >>> +
> >>> +struct imx_sc_msg_pwrkey {
> >>> +	struct imx_sc_rpc_msg hdr;
> >>> +	u8 state;
> >>> +};
> >>> +static struct imx_pwrkey_drv_data *pdata;
> >>
> >> Why is it global struct? It seems to be flexible configurable over devicetree.
> >> So I would assume it should be able to handle more then one button.
> >> Please remove global variables, make it allocatable per OF node.
> >
> > There is ONLY one button available for SC key, but yes, I think I can
> > make the structure private and get all necessary data from the structure
> using container_of.
> 
> And we will never need more then 640 kB RAM ;)
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fen.wi
> kiquote.org%2Fwiki%2FTalk%3ABill_Gates&amp;data=02%7C01%7Canson.hu
> ang%40nxp.com%7C4d4d7458087747e0d8f008d7304057e9%7C686ea1d3bc2
> b4c6fa92cd99c5c301635%7C0%7C0%7C637030925236150243&amp;sdata=w
> %2FGXBaHfnBdLwjTxjbzWSPeIw3ExL%2Fs9IMOgF1onL6A%3D&amp;reserved
> =0
> 
> >
> >>
> >> Please use different name "pdata" is usually used as platform data.
> >> Please, use "priv".
> >
> > OK.
> >
> >>
> >>> +static struct imx_sc_ipc *pwrkey_ipc_handle;
> >>
> >> same as before, no global variables.
> >
> > Will move it into private platform data structure.
> >
> >>
> >>> +
> >>> +static int imx_sc_pwrkey_notify(struct notifier_block *nb,
> >>> +				unsigned long event, void *group) {
> >>> +	if ((event & SC_IRQ_BUTTON) && (*(u8 *)group ==
> >> SC_IRQ_GROUP_WAKE)
> >>> +	    && !pdata->delay_check) {
> >>> +		pdata->delay_check = 1;
> >>> +		schedule_delayed_work(&pdata->check_work,
> >>> +				      msecs_to_jiffies(REPEAT_INTERVAL));
> >>> +	}
> >>> +
> >>> +	return 0;
> >>> +}
> >>> +
> >>> +static void imx_sc_check_for_events(struct work_struct *work) {
> >>> +	struct input_dev *input = pdata->input;
> >>> +	struct imx_sc_msg_pwrkey msg;
> >>> +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
> >>> +	bool state;
> >>> +
> >>> +	hdr->ver = IMX_SC_RPC_VERSION;
> >>> +	hdr->svc = IMX_SC_RPC_SVC_MISC;
> >>> +	hdr->func = IMX_SC_MISC_FUNC_GET_BUTTON_STATUS;
> >>> +	hdr->size = 1;
> >>> +
> >>> +	/*
> >>> +	 * Current SCU firmware does NOT have return value for
> >>> +	 * this API, that means it is always successful.
> >>> +	 */
> >>
> >> It is not true for the kernel part:
> >> https://elixir.
> >>
> bootlin.com%2Flinux%2Flatest%2Fsource%2Fdrivers%2Ffirmware%2Fimx%2F
> >> imx-
> >>
> scu.c%23L157&amp;data=02%7C01%7Canson.huang%40nxp.com%7C7a5ed3
> >>
> ef3b2541e61be808d7303810a9%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C
> >>
> 0%7C0%7C637030889669489141&amp;sdata=d3uw6x6WCPeavJu3QYf9o9cxx
> >> Rx4mJar04fQFLF9EhE%3D&amp;reserved=0
> >>
> >> imx_scu_call_rpc() may fail in different ways and provide proper error
> value.
> >> Please use it.
> >
> > There are about 3 APIs are special, this API is one of them, this API
> > has no return value from SCU FW API, but it has response data from it,
> > so that means if we set the response to false, the stack will be free
> > and mailbox will have NULL pointer issue when response data passed
> > from SCU FW. If we set the response to true, as the SCU FW has no
> > return value, the return value will be the msg->func which will be
> > already failed, that is why we have to skip the return value check. This is
> one restriction/bug of SCU FW, we will notify SCU FW owner to fix/improve.
> 
> Ok, I see. imx_scu_call_rpc() can return kernel side errors, for example from
> imx-scu.c framework EINVAL or ETIMEDOUT or what ever error mbox
> framework may also provide.
> Aaaannnndd... it can extract an error from SCU package and return it over
> same way as other errors.
> 
> And current SCU version has some bugs, so it is providing wrong error value.
> Soo... as usual the NXP has decided to make the linux kernel a bit more
> worse to make the SCU firmware happy? Is it what you trying to describe?
> Really ?! :D
> 
> Please. Fix the SCU first. The provide fixed kernel patch.

Understood, I will notify SCU owner to fix it, meanwhile it does NOT block this driver,
I will add return value check in this driver.

Thanks,
Anson

Re: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Oleksij Rempel]

On 03.09.19 09:35, Anson Huang wrote:
> Hi, Oleksij
> 
>> On 03.09.19 08:48, Anson Huang wrote:
>>> Hi, Oleksij
>>>
>>>> On 03.09.19 16:03, Anson Huang wrote:
>>>>> i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
>>>>> inside, the system controller is in charge of controlling power,
>>>>> clock and power key etc..
>>>>>
>>>>> Adds i.MX system controller power key driver support, Linux kernel
>>>>> has to communicate with system controller via MU (message unit) IPC
>>>>> to get power key's status.
>>>>>
>>>>> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
>>>>> ---
>>>>> Changes since V1:
>>>>> 	- remove "wakeup-source" property operation, scu power key uses
>>>> generic scu irq,
>>>>> 	  no need to have this property for device wakeup operation.
>>>>> ---
>>>>>     drivers/input/keyboard/Kconfig         |   7 ++
>>>>>     drivers/input/keyboard/Makefile        |   1 +
>>>>>     drivers/input/keyboard/imx_sc_pwrkey.c | 169
>>>> +++++++++++++++++++++++++++++++++
>>>>>     3 files changed, 177 insertions(+)
>>>>>     create mode 100644 drivers/input/keyboard/imx_sc_pwrkey.c
>>>>>
>>>>> diff --git a/drivers/input/keyboard/Kconfig
>>>>> b/drivers/input/keyboard/Kconfig index 2e6d288..3aaeb9c 100644
>>>>> --- a/drivers/input/keyboard/Kconfig
>>>>> +++ b/drivers/input/keyboard/Kconfig
>>>>> @@ -469,6 +469,13 @@ config KEYBOARD_IMX
>>>>>     	  To compile this driver as a module, choose M here: the
>>>>>     	  module will be called imx_keypad.
>>>>>
>>>>> +config KEYBOARD_IMX_SC_PWRKEY
>>>>> +	tristate "IMX SCU Power Key Driver"
>>>>> +	depends on IMX_SCU
>>>>> +	help
>>>>> +	  This is the system controller powerkey driver for NXP i.MX SoCs with
>>>>> +	  system controller inside.
>>>>
>>>> The KEY is configurable over devicetree, why is it called PWRKEY? It
>>>> looks for me as generic SCU key handler.
>>>
>>> We always use it as power key, NOT a generic key, as it has HW
>>> function designed for power key purpose.
>>
>> gpio-key driver is mostly used for power or reboot key. And it is still called
>> gpio-key driver. If it is used for power key only, why is it configurable? I can
>> configure it as KEY_ENTER or some thing different. This driver has not
>> KEY_POWER specific any thing.
> 
> Understood, I am making the V3 with all "power" removed, just using the "key".
> 
>>
>>>
>>>>
>>>>>     config KEYBOARD_NEWTON
>>>>>     	tristate "Newton keyboard"
>>>>>     	select SERIO
>>>>> diff --git a/drivers/input/keyboard/Makefile
>>>>> b/drivers/input/keyboard/Makefile index 9510325..9ea5585 100644
>>>>> --- a/drivers/input/keyboard/Makefile
>>>>> +++ b/drivers/input/keyboard/Makefile
>>>>> @@ -29,6 +29,7 @@ obj-$(CONFIG_KEYBOARD_HIL)		+=
>> hil_kbd.o
>>>>>     obj-$(CONFIG_KEYBOARD_HIL_OLD)		+= hilkbd.o
>>>>>     obj-$(CONFIG_KEYBOARD_IPAQ_MICRO)	+= ipaq-micro-keys.o
>>>>>     obj-$(CONFIG_KEYBOARD_IMX)		+= imx_keypad.o
>>>>> +obj-$(CONFIG_KEYBOARD_IMX_SC_PWRKEY)	+= imx_sc_pwrkey.o
>>>>>     obj-$(CONFIG_KEYBOARD_HP6XX)		+= jornada680_kbd.o
>>>>>     obj-$(CONFIG_KEYBOARD_HP7XX)		+= jornada720_kbd.o
>>>>>     obj-$(CONFIG_KEYBOARD_LKKBD)		+= lkkbd.o
>>>>> diff --git a/drivers/input/keyboard/imx_sc_pwrkey.c
>>>>> b/drivers/input/keyboard/imx_sc_pwrkey.c
>>>>> new file mode 100644
>>>>> index 0000000..53aa9a4
>>>>> --- /dev/null
>>>>> +++ b/drivers/input/keyboard/imx_sc_pwrkey.c
>>>>> @@ -0,0 +1,169 @@
>>>>> +// SPDX-License-Identifier: GPL-2.0
>>>>> +/*
>>>>> + * Copyright 2019 NXP.
>>>>> + */
>>>>> +
>>>>> +#include <linux/device.h>
>>>>> +#include <linux/err.h>
>>>>> +#include <linux/firmware/imx/sci.h> #include <linux/init.h>
>>>>> +#include <linux/input.h> #include <linux/interrupt.h> #include
>>>>> +<linux/jiffies.h> #include <linux/kernel.h> #include
>>>>> +<linux/module.h> #include <linux/of.h> #include
>>>>> +<linux/of_address.h> #include <linux/platform_device.h>
>>>>> +
>>>>> +#define DEBOUNCE_TIME	100
>>>>> +#define REPEAT_INTERVAL	60
>>>>> +
>>>>> +#define SC_IRQ_BUTTON		1
>>>>> +#define SC_IRQ_GROUP_WAKE	3
>>>>> +#define IMX_SC_MISC_FUNC_GET_BUTTON_STATUS	18
>>>>> +
>>>>> +struct imx_pwrkey_drv_data {
>>>>> +	int keycode;
>>>>> +	bool keystate;  /* 1: pressed, 0: release */
>>>>> +	bool delay_check;
>>>>> +	struct delayed_work check_work;
>>>>> +	struct input_dev *input;
>>>>> +};
>>>>> +
>>>>> +struct imx_sc_msg_pwrkey {
>>>>> +	struct imx_sc_rpc_msg hdr;
>>>>> +	u8 state;
>>>>> +};
>>>>> +static struct imx_pwrkey_drv_data *pdata;
>>>>
>>>> Why is it global struct? It seems to be flexible configurable over devicetree.
>>>> So I would assume it should be able to handle more then one button.
>>>> Please remove global variables, make it allocatable per OF node.
>>>
>>> There is ONLY one button available for SC key, but yes, I think I can
>>> make the structure private and get all necessary data from the structure
>> using container_of.
>>
>> And we will never need more then 640 kB RAM ;)
>> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fen.wi
>> kiquote.org%2Fwiki%2FTalk%3ABill_Gates&amp;data=02%7C01%7Canson.hu
>> ang%40nxp.com%7C4d4d7458087747e0d8f008d7304057e9%7C686ea1d3bc2
>> b4c6fa92cd99c5c301635%7C0%7C0%7C637030925236150243&amp;sdata=w
>> %2FGXBaHfnBdLwjTxjbzWSPeIw3ExL%2Fs9IMOgF1onL6A%3D&amp;reserved
>> =0
>>
>>>
>>>>
>>>> Please use different name "pdata" is usually used as platform data.
>>>> Please, use "priv".
>>>
>>> OK.
>>>
>>>>
>>>>> +static struct imx_sc_ipc *pwrkey_ipc_handle;
>>>>
>>>> same as before, no global variables.
>>>
>>> Will move it into private platform data structure.
>>>
>>>>
>>>>> +
>>>>> +static int imx_sc_pwrkey_notify(struct notifier_block *nb,
>>>>> +				unsigned long event, void *group) {
>>>>> +	if ((event & SC_IRQ_BUTTON) && (*(u8 *)group ==
>>>> SC_IRQ_GROUP_WAKE)
>>>>> +	    && !pdata->delay_check) {
>>>>> +		pdata->delay_check = 1;
>>>>> +		schedule_delayed_work(&pdata->check_work,
>>>>> +				      msecs_to_jiffies(REPEAT_INTERVAL));
>>>>> +	}
>>>>> +
>>>>> +	return 0;
>>>>> +}
>>>>> +
>>>>> +static void imx_sc_check_for_events(struct work_struct *work) {
>>>>> +	struct input_dev *input = pdata->input;
>>>>> +	struct imx_sc_msg_pwrkey msg;
>>>>> +	struct imx_sc_rpc_msg *hdr = &msg.hdr;
>>>>> +	bool state;
>>>>> +
>>>>> +	hdr->ver = IMX_SC_RPC_VERSION;
>>>>> +	hdr->svc = IMX_SC_RPC_SVC_MISC;
>>>>> +	hdr->func = IMX_SC_MISC_FUNC_GET_BUTTON_STATUS;
>>>>> +	hdr->size = 1;
>>>>> +
>>>>> +	/*
>>>>> +	 * Current SCU firmware does NOT have return value for
>>>>> +	 * this API, that means it is always successful.
>>>>> +	 */
>>>>
>>>> It is not true for the kernel part:
>>>> https://elixir.
>>>>
>> bootlin.com%2Flinux%2Flatest%2Fsource%2Fdrivers%2Ffirmware%2Fimx%2F
>>>> imx-
>>>>
>> scu.c%23L157&amp;data=02%7C01%7Canson.huang%40nxp.com%7C7a5ed3
>>>>
>> ef3b2541e61be808d7303810a9%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C
>>>>
>> 0%7C0%7C637030889669489141&amp;sdata=d3uw6x6WCPeavJu3QYf9o9cxx
>>>> Rx4mJar04fQFLF9EhE%3D&amp;reserved=0
>>>>
>>>> imx_scu_call_rpc() may fail in different ways and provide proper error
>> value.
>>>> Please use it.
>>>
>>> There are about 3 APIs are special, this API is one of them, this API
>>> has no return value from SCU FW API, but it has response data from it,
>>> so that means if we set the response to false, the stack will be free
>>> and mailbox will have NULL pointer issue when response data passed
>>> from SCU FW. If we set the response to true, as the SCU FW has no
>>> return value, the return value will be the msg->func which will be
>>> already failed, that is why we have to skip the return value check. This is
>> one restriction/bug of SCU FW, we will notify SCU FW owner to fix/improve.
>>
>> Ok, I see. imx_scu_call_rpc() can return kernel side errors, for example from
>> imx-scu.c framework EINVAL or ETIMEDOUT or what ever error mbox
>> framework may also provide.
>> Aaaannnndd... it can extract an error from SCU package and return it over
>> same way as other errors.
>>
>> And current SCU version has some bugs, so it is providing wrong error value.
>> Soo... as usual the NXP has decided to make the linux kernel a bit more
>> worse to make the SCU firmware happy? Is it what you trying to describe?
>> Really ?! :D
>>
>> Please. Fix the SCU first. The provide fixed kernel patch.
> 
> Understood, I will notify SCU owner to fix it, meanwhile it does NOT block this driver,
> I will add return value check in this driver.

It is great! Thank you!

Kind regards,
Oleksij Rempel

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

[PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Anson Huang]

NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as
system controller, the system controller is in charge of system
power, clock and power key event etc. management, Linux kernel
has to communicate with system controller via MU (message unit)
IPC to get power key event, add binding doc for i.MX system
controller power key driver.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
Changes since V1:
	- remove "wakeup-source" property, as it is NOT needed for SCU interrupt;
	- remove "status" in example.
---
 .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
index c149fad..f93e2e4 100644
--- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
+++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
@@ -157,6 +157,15 @@ Required properties:
 Optional properties:
 - timeout-sec: contains the watchdog timeout in seconds.
 
+Power key bindings based on SCU Message Protocol
+------------------------------------------------------------
+
+Required properties:
+- compatible: should be:
+              "fsl,imx8qxp-sc-pwrkey"
+              followed by "fsl,imx-sc-pwrkey";
+- linux,keycodes: See Documentation/devicetree/bindings/input/keys.txt
+
 Example (imx8qxp):
 -------------
 aliases {
@@ -220,6 +229,11 @@ firmware {
 			compatible = "fsl,imx8qxp-sc-rtc";
 		};
 
+		scu_pwrkey: scu-pwrkey {
+			compatible = "fsl,imx8qxp-sc-pwrkey", "fsl,imx-sc-pwrkey";
+			linux,keycode = <KEY_POWER>;
+		};
+
 		watchdog {
 			compatible = "fsl,imx8qxp-sc-wdt", "fsl,imx-sc-wdt";
 			timeout-sec = <60>;
-- 
2.7.4

[PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Anson Huang]

i.MX8QXP is an ARMv8 SoC which has a Cortex-M4 system controller
inside, the system controller is in charge of controlling power,
clock and power key etc..

Adds i.MX system controller power key driver support, Linux kernel
has to communicate with system controller via MU (message unit) IPC
to get power key's status.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
Changes since V1:
	- remove "wakeup-source" property operation, scu power key uses generic scu irq,
	  no need to have this property for device wakeup operation.
---
 drivers/input/keyboard/Kconfig         |   7 ++
 drivers/input/keyboard/Makefile        |   1 +
 drivers/input/keyboard/imx_sc_pwrkey.c | 169 +++++++++++++++++++++++++++++++++
 3 files changed, 177 insertions(+)
 create mode 100644 drivers/input/keyboard/imx_sc_pwrkey.c

diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
index 2e6d288..3aaeb9c 100644
--- a/drivers/input/keyboard/Kconfig
+++ b/drivers/input/keyboard/Kconfig
@@ -469,6 +469,13 @@ config KEYBOARD_IMX
 	  To compile this driver as a module, choose M here: the
 	  module will be called imx_keypad.
 
+config KEYBOARD_IMX_SC_PWRKEY
+	tristate "IMX SCU Power Key Driver"
+	depends on IMX_SCU
+	help
+	  This is the system controller powerkey driver for NXP i.MX SoCs with
+	  system controller inside.
+
 config KEYBOARD_NEWTON
 	tristate "Newton keyboard"
 	select SERIO
diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
index 9510325..9ea5585 100644
--- a/drivers/input/keyboard/Makefile
+++ b/drivers/input/keyboard/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_KEYBOARD_HIL)		+= hil_kbd.o
 obj-$(CONFIG_KEYBOARD_HIL_OLD)		+= hilkbd.o
 obj-$(CONFIG_KEYBOARD_IPAQ_MICRO)	+= ipaq-micro-keys.o
 obj-$(CONFIG_KEYBOARD_IMX)		+= imx_keypad.o
+obj-$(CONFIG_KEYBOARD_IMX_SC_PWRKEY)	+= imx_sc_pwrkey.o
 obj-$(CONFIG_KEYBOARD_HP6XX)		+= jornada680_kbd.o
 obj-$(CONFIG_KEYBOARD_HP7XX)		+= jornada720_kbd.o
 obj-$(CONFIG_KEYBOARD_LKKBD)		+= lkkbd.o
diff --git a/drivers/input/keyboard/imx_sc_pwrkey.c b/drivers/input/keyboard/imx_sc_pwrkey.c
new file mode 100644
index 0000000..53aa9a4
--- /dev/null
+++ b/drivers/input/keyboard/imx_sc_pwrkey.c
@@ -0,0 +1,169 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 NXP.
+ */
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/firmware/imx/sci.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+
+#define DEBOUNCE_TIME	100
+#define REPEAT_INTERVAL	60
+
+#define SC_IRQ_BUTTON		1
+#define SC_IRQ_GROUP_WAKE	3
+#define IMX_SC_MISC_FUNC_GET_BUTTON_STATUS	18
+
+struct imx_pwrkey_drv_data {
+	int keycode;
+	bool keystate;  /* 1: pressed, 0: release */
+	bool delay_check;
+	struct delayed_work check_work;
+	struct input_dev *input;
+};
+
+struct imx_sc_msg_pwrkey {
+	struct imx_sc_rpc_msg hdr;
+	u8 state;
+};
+static struct imx_pwrkey_drv_data *pdata;
+static struct imx_sc_ipc *pwrkey_ipc_handle;
+
+static int imx_sc_pwrkey_notify(struct notifier_block *nb,
+				unsigned long event, void *group)
+{
+	if ((event & SC_IRQ_BUTTON) && (*(u8 *)group == SC_IRQ_GROUP_WAKE)
+	    && !pdata->delay_check) {
+		pdata->delay_check = 1;
+		schedule_delayed_work(&pdata->check_work,
+				      msecs_to_jiffies(REPEAT_INTERVAL));
+	}
+
+	return 0;
+}
+
+static void imx_sc_check_for_events(struct work_struct *work)
+{
+	struct input_dev *input = pdata->input;
+	struct imx_sc_msg_pwrkey msg;
+	struct imx_sc_rpc_msg *hdr = &msg.hdr;
+	bool state;
+
+	hdr->ver = IMX_SC_RPC_VERSION;
+	hdr->svc = IMX_SC_RPC_SVC_MISC;
+	hdr->func = IMX_SC_MISC_FUNC_GET_BUTTON_STATUS;
+	hdr->size = 1;
+
+	/*
+	 * Current SCU firmware does NOT have return value for
+	 * this API, that means it is always successful.
+	 */
+	imx_scu_call_rpc(pwrkey_ipc_handle, &msg, true);
+	state = msg.state;
+
+	if (!state && !pdata->keystate)
+		state = true;
+
+	if (state ^ pdata->keystate) {
+		pm_wakeup_event(input->dev.parent, 0);
+		pdata->keystate = !!state;
+		input_event(input, EV_KEY, pdata->keycode, !!state);
+		input_sync(input);
+		if (!state)
+			pdata->delay_check = 0;
+		pm_relax(pdata->input->dev.parent);
+	}
+
+	if (state)
+		schedule_delayed_work(&pdata->check_work,
+				      msecs_to_jiffies(DEBOUNCE_TIME));
+}
+
+static struct notifier_block imx_sc_pwrkey_notifier = {
+	.notifier_call = imx_sc_pwrkey_notify,
+};
+
+static int imx_sc_pwrkey_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct input_dev *input;
+	int ret;
+
+	ret = imx_scu_get_handle(&pwrkey_ipc_handle);
+	if (ret)
+		return ret;
+
+	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+
+	if (of_property_read_u32(np, "linux,keycode", &pdata->keycode)) {
+		pdata->keycode = KEY_POWER;
+		dev_warn(&pdev->dev, "KEY_POWER without setting in dts\n");
+	}
+
+	INIT_DELAYED_WORK(&pdata->check_work, imx_sc_check_for_events);
+
+	input = devm_input_allocate_device(&pdev->dev);
+	if (!input) {
+		dev_err(&pdev->dev, "failed to allocate the input device\n");
+		return -ENOMEM;
+	}
+
+	input->name = pdev->name;
+	input->phys = "imx-sc-pwrkey/input0";
+	input->id.bustype = BUS_HOST;
+
+	input_set_capability(input, EV_KEY, pdata->keycode);
+
+	ret = input_register_device(input);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to register input device\n");
+		return ret;
+	}
+
+	pdata->input = input;
+	platform_set_drvdata(pdev, pdata);
+
+	ret = imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, true);
+	if (ret) {
+		dev_warn(&pdev->dev, "enable scu group irq failed\n");
+		return ret;
+	}
+
+	ret = imx_scu_irq_register_notifier(&imx_sc_pwrkey_notifier);
+	if (ret) {
+		imx_scu_irq_group_enable(SC_IRQ_GROUP_WAKE, SC_IRQ_BUTTON, false);
+		dev_warn(&pdev->dev, "register scu notifier failed\n");
+	}
+
+	return ret;
+}
+
+static const struct of_device_id imx_sc_pwrkey_ids[] = {
+	{ .compatible = "fsl,imx-sc-pwrkey" },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_sc_pwrkey_ids);
+
+static struct platform_driver imx_sc_pwrkey_driver = {
+	.driver = {
+		.name = "imx-sc-pwrkey",
+		.of_match_table = imx_sc_pwrkey_ids,
+	},
+	.probe = imx_sc_pwrkey_probe,
+};
+module_platform_driver(imx_sc_pwrkey_driver);
+
+MODULE_AUTHOR("Anson Huang <Anson.Huang@nxp.com>");
+MODULE_DESCRIPTION("i.MX System Controller Power Key Driver");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4

[PATCH V2 3/5] arm64: dts: imx8qxp: Add scu power key node

[Anson Huang]

Add scu power key node for i.MX8QXP, disabled by default as it
depends on board design.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
Changes since V1:
	- remove "wakeup-source" property, as it is NOT needed for scu mu interrupt;
---
 arch/arm64/boot/dts/freescale/imx8qxp.dtsi | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8qxp.dtsi b/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
index 1133b41..85c5534 100644
--- a/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
@@ -8,6 +8,7 @@
 #include <dt-bindings/clock/imx8-clock.h>
 #include <dt-bindings/firmware/imx/rsrc.h>
 #include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/input/input.h>
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <dt-bindings/pinctrl/pads-imx8qxp.h>
 
@@ -174,6 +175,12 @@
 			#power-domain-cells = <1>;
 		};
 
+		scu_pwrkey: scu-pwrkey {
+			compatible = "fsl,imx8qxp-sc-pwrkey", "fsl,imx-sc-pwrkey";
+			linux,keycode = <KEY_POWER>;
+			status = "disabled";
+		};
+
 		rtc: rtc {
 			compatible = "fsl,imx8qxp-sc-rtc";
 		};
-- 
2.7.4

[PATCH V2 4/5] arm64: dts: imx8qxp-mek: Enable scu power key

[Anson Huang]

Enable scu power key for i.MX8QXP MEK board.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
No changes.
---
 arch/arm64/boot/dts/freescale/imx8qxp-mek.dts | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8qxp-mek.dts b/arch/arm64/boot/dts/freescale/imx8qxp-mek.dts
index 1946805..f3df5c4 100644
--- a/arch/arm64/boot/dts/freescale/imx8qxp-mek.dts
+++ b/arch/arm64/boot/dts/freescale/imx8qxp-mek.dts
@@ -234,3 +234,7 @@
 &adma_dsp {
 	status = "okay";
 };
+
+&scu_pwrkey {
+	status = "okay";
+};
-- 
2.7.4

[PATCH V2 5/5] arm64: defconfig: Enable CONFIG_KEYBOARD_IMX_SC_PWRKEY as module

[Anson Huang]

Select CONFIG_KEYBOARD_IMX_SC_PWRKEY as module by default to
support i.MX8QXP power key driver.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
---
No changes.
---
 arch/arm64/configs/defconfig | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/configs/defconfig b/arch/arm64/configs/defconfig
index 49bb3d4..8178737 100644
--- a/arch/arm64/configs/defconfig
+++ b/arch/arm64/configs/defconfig
@@ -313,6 +313,7 @@ CONFIG_INPUT_EVDEV=y
 CONFIG_KEYBOARD_ADC=m
 CONFIG_KEYBOARD_GPIO=y
 CONFIG_KEYBOARD_SNVS_PWRKEY=m
+CONFIG_KEYBOARD_IMX_SC_PWRKEY=m
 CONFIG_KEYBOARD_CROS_EC=y
 CONFIG_INPUT_TOUCHSCREEN=y
 CONFIG_TOUCHSCREEN_ATMEL_MXT=m
-- 
2.7.4

Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Pavel Machek]

Hi!

> NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as
> system controller, the system controller is in charge of system
> power, clock and power key event etc. management, Linux kernel
> has to communicate with system controller via MU (message unit)
> IPC to get power key event, add binding doc for i.MX system
> controller power key driver.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>

> +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> @@ -157,6 +157,15 @@ Required properties:
>  Optional properties:
>  - timeout-sec: contains the watchdog timeout in seconds.
>  
> +Power key bindings based on SCU Message Protocol
> +------------------------------------------------------------
> +
> +Required properties:
> +- compatible: should be:
> +              "fsl,imx8qxp-sc-pwrkey"
> +              followed by "fsl,imx-sc-pwrkey";
> +- linux,keycodes: See Documentation/devicetree/bindings/input/keys.txt

Actually there's no reason for having "linux,keycodes" property when it is always
a power button.

Best regards,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH V2 2/5] input: keyboard: imx_sc: Add i.MX system controller power key support

[Pavel Machek]

Hi!

> >>Why is it global struct? It seems to be flexible configurable over devicetree.
> >>So I would assume it should be able to handle more then one button. Please
> >>remove global variables, make it allocatable per OF node.
> >
> >There is ONLY one button available for SC key, but yes, I think I can make the structure
> >private and get all necessary data from the structure using container_of.
> 
> And we will never need more then 640 kB RAM ;)
> https://en.wikiquote.org/wiki/Talk:Bill_Gates

Right question is "is it worth complicating kernel now (and making it slower/bigger)
for future flexibility?". And I believe answer is "no", but it is not a big deal
either way.								Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Pavel Machek]

On Tue 2019-09-03 10:03:40, Anson Huang wrote:
> NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as
> system controller, the system controller is in charge of system
> power, clock and power key event etc. management, Linux kernel
> has to communicate with system controller via MU (message unit)
> IPC to get power key event, add binding doc for i.MX system
> controller power key driver.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> ---
> Changes since V1:
> 	- remove "wakeup-source" property, as it is NOT needed for SCU interrupt;
> 	- remove "status" in example.
> ---
>  .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> index c149fad..f93e2e4 100644
> --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> @@ -157,6 +157,15 @@ Required properties:
>  Optional properties:
>  - timeout-sec: contains the watchdog timeout in seconds.
>  
> +Power key bindings based on SCU Message Protocol
> +------------------------------------------------------------
> +
> +Required properties:
> +- compatible: should be:
> +              "fsl,imx8qxp-sc-pwrkey"
> +              followed by "fsl,imx-sc-pwrkey";
> +- linux,keycodes: See Documentation/devicetree/bindings/input/keys.txt

Note you have keycode_s_ here, but keycode in the example and in the dts patch.

									Pavel

-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

RE: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Anson Huang]

Hi, Pavel

> Subject: Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding
> 
> Hi!
> 
> > NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
> > controller, the system controller is in charge of system power, clock
> > and power key event etc. management, Linux kernel has to communicate
> > with system controller via MU (message unit) IPC to get power key
> > event, add binding doc for i.MX system controller power key driver.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> 
> > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > @@ -157,6 +157,15 @@ Required properties:
> >  Optional properties:
> >  - timeout-sec: contains the watchdog timeout in seconds.
> >
> > +Power key bindings based on SCU Message Protocol
> > +------------------------------------------------------------
> > +
> > +Required properties:
> > +- compatible: should be:
> > +              "fsl,imx8qxp-sc-pwrkey"
> > +              followed by "fsl,imx-sc-pwrkey";
> > +- linux,keycodes: See
> > +Documentation/devicetree/bindings/input/keys.txt
> 
> Actually there's no reason for having "linux,keycodes" property when it is
> always a power button.
The latest version of patch already change the compatible name to *-sc-key which
is more general as key driver, so the "linux,keycodes" is needed now for driver
to define the key function.

Thanks,
Anson 

RE: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Anson Huang]

Hi, Pavel

> Subject: Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding
> 
> On Tue 2019-09-03 10:03:40, Anson Huang wrote:
> > NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
> > controller, the system controller is in charge of system power, clock
> > and power key event etc. management, Linux kernel has to communicate
> > with system controller via MU (message unit) IPC to get power key
> > event, add binding doc for i.MX system controller power key driver.
> >
> > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > ---
> > Changes since V1:
> > 	- remove "wakeup-source" property, as it is NOT needed for SCU
> interrupt;
> > 	- remove "status" in example.
> > ---
> >  .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14
> ++++++++++++++
> >  1 file changed, 14 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > index c149fad..f93e2e4 100644
> > --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > @@ -157,6 +157,15 @@ Required properties:
> >  Optional properties:
> >  - timeout-sec: contains the watchdog timeout in seconds.
> >
> > +Power key bindings based on SCU Message Protocol
> > +------------------------------------------------------------
> > +
> > +Required properties:
> > +- compatible: should be:
> > +              "fsl,imx8qxp-sc-pwrkey"
> > +              followed by "fsl,imx-sc-pwrkey";
> > +- linux,keycodes: See
> > +Documentation/devicetree/bindings/input/keys.txt
> 
> Note you have keycode_s_ here, but keycode in the example and in the dts
> patch.

NOT quite understand your point, could you please provide more details?

Thanks,
Anson

Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Shawn Guo]

On Mon, Sep 23, 2019 at 02:34:07AM +0000, Anson Huang wrote:
> Hi, Pavel
> 
> > Subject: Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding
> > 
> > On Tue 2019-09-03 10:03:40, Anson Huang wrote:
> > > NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
> > > controller, the system controller is in charge of system power, clock
> > > and power key event etc. management, Linux kernel has to communicate
> > > with system controller via MU (message unit) IPC to get power key
> > > event, add binding doc for i.MX system controller power key driver.
> > >
> > > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > > ---
> > > Changes since V1:
> > > 	- remove "wakeup-source" property, as it is NOT needed for SCU
> > interrupt;
> > > 	- remove "status" in example.
> > > ---
> > >  .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14
> > ++++++++++++++
> > >  1 file changed, 14 insertions(+)
> > >
> > > diff --git
> > > a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > index c149fad..f93e2e4 100644
> > > --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > @@ -157,6 +157,15 @@ Required properties:
> > >  Optional properties:
> > >  - timeout-sec: contains the watchdog timeout in seconds.
> > >
> > > +Power key bindings based on SCU Message Protocol
> > > +------------------------------------------------------------
> > > +
> > > +Required properties:
> > > +- compatible: should be:
> > > +              "fsl,imx8qxp-sc-pwrkey"
> > > +              followed by "fsl,imx-sc-pwrkey";
> > > +- linux,keycodes: See
> > > +Documentation/devicetree/bindings/input/keys.txt
> > 
> > Note you have keycode_s_ here, but keycode in the example and in the dts
> > patch.
> 
> NOT quite understand your point, could you please provide more details?

The property being used in driver, DTS, and DT example in the
bindings are all 'linux,keycode' rather than 'linux,keycodes'.

Shawn

RE: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key binding

[Anson Huang]

Hi, Shawn

> On Mon, Sep 23, 2019 at 02:34:07AM +0000, Anson Huang wrote:
> > Hi, Pavel
> >
> > > Subject: Re: [PATCH V2 1/5] dt-bindings: fsl: scu: add scu power key
> > > binding
> > >
> > > On Tue 2019-09-03 10:03:40, Anson Huang wrote:
> > > > NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as
> > > > system controller, the system controller is in charge of system
> > > > power, clock and power key event etc. management, Linux kernel has
> > > > to communicate with system controller via MU (message unit) IPC to
> > > > get power key event, add binding doc for i.MX system controller power
> key driver.
> > > >
> > > > Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> > > > ---
> > > > Changes since V1:
> > > > 	- remove "wakeup-source" property, as it is NOT needed for SCU
> > > interrupt;
> > > > 	- remove "status" in example.
> > > > ---
> > > >  .../devicetree/bindings/arm/freescale/fsl,scu.txt          | 14
> > > ++++++++++++++
> > > >  1 file changed, 14 insertions(+)
> > > >
> > > > diff --git
> > > > a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > > b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > > index c149fad..f93e2e4 100644
> > > > --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > > @@ -157,6 +157,15 @@ Required properties:
> > > >  Optional properties:
> > > >  - timeout-sec: contains the watchdog timeout in seconds.
> > > >
> > > > +Power key bindings based on SCU Message Protocol
> > > > +------------------------------------------------------------
> > > > +
> > > > +Required properties:
> > > > +- compatible: should be:
> > > > +              "fsl,imx8qxp-sc-pwrkey"
> > > > +              followed by "fsl,imx-sc-pwrkey";
> > > > +- linux,keycodes: See
> > > > +Documentation/devicetree/bindings/input/keys.txt
> > >
> > > Note you have keycode_s_ here, but keycode in the example and in the
> > > dts patch.
> >
> > NOT quite understand your point, could you please provide more details?
> 
> The property being used in driver, DTS, and DT example in the bindings are
> all 'linux,keycode' rather than 'linux,keycodes'.

I see now, since Documentation/devicetree/bindings/input/keys.txt uses "linux,keycodes",
so I will also use "linux,keycodes" for driver, DTS and DT example in V3.

Thanks,
Anson