Re: [PATCH v7 7/7] input: keyboard: support i.MX95 BBM module

[Cristian Marussi]

On Wed, Jul 31, 2024 at 08:56:11PM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@xxxxxxx>
> 
> The BBM module provides BUTTON feature. To i.MX95, this module
> is managed by System Manager and exported using System Management
> Control Interface(SCMI). Linux could use i.MX SCMI BBM Extension
> protocol to use BUTTON feature.
> 
> This driver is to use SCMI interface to enable pwrkey.
> 

Hi Peng,


> Signed-off-by: Peng Fan <peng.fan@xxxxxxx>
> ---
>  drivers/input/keyboard/Kconfig          |  11 ++
>  drivers/input/keyboard/Makefile         |   1 +
>  drivers/input/keyboard/imx-sm-bbm-key.c | 236 ++++++++++++++++++++++++++++++++
>  3 files changed, 248 insertions(+)
> 
> diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> index 72f9552cb571..a3301239b9a6 100644
> --- a/drivers/input/keyboard/Kconfig
> +++ b/drivers/input/keyboard/Kconfig
> @@ -454,6 +454,17 @@ config KEYBOARD_IMX
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called imx_keypad.
>  
> +config KEYBOARD_IMX_BBM_SCMI
> +	tristate "IMX BBM SCMI Key Driver"
> +	depends on IMX_SCMI_BBM_EXT || COMPILE_TEST
> +	default y if ARCH_MXC
> +	help
> +	  This is the BBM key driver for NXP i.MX SoCs managed through
> +	  SCMI protocol.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called scmi-imx-bbm-key.
> +
>  config KEYBOARD_IMX_SC_KEY
>  	tristate "IMX SCU Key Driver"
>  	depends on IMX_SCU
> diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> index b8d12a0524e0..5915e52eac28 100644
> --- a/drivers/input/keyboard/Makefile
> +++ b/drivers/input/keyboard/Makefile
> @@ -31,6 +31,7 @@ obj-$(CONFIG_KEYBOARD_IPAQ_MICRO)	+= ipaq-micro-keys.o
>  obj-$(CONFIG_KEYBOARD_IQS62X)		+= iqs62x-keys.o
>  obj-$(CONFIG_KEYBOARD_IMX)		+= imx_keypad.o
>  obj-$(CONFIG_KEYBOARD_IMX_SC_KEY)	+= imx_sc_key.o
> +obj-$(CONFIG_KEYBOARD_IMX_BBM_SCMI)	+= imx-sm-bbm-key.o
>  obj-$(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-sm-bbm-key.c b/drivers/input/keyboard/imx-sm-bbm-key.c
> new file mode 100644
> index 000000000000..ca430dbb61d0
> --- /dev/null
> +++ b/drivers/input/keyboard/imx-sm-bbm-key.c
> @@ -0,0 +1,236 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright 2024 NXP.
> + */
> +
> +#include <linux/input.h>
> +#include <linux/jiffies.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/platform_device.h>
> +#include <linux/rtc.h>
> +#include <linux/scmi_protocol.h>
> +#include <linux/scmi_imx_protocol.h>
> +#include <linux/suspend.h>
> +
> +#define DEBOUNCE_TIME		30
> +#define REPEAT_INTERVAL		60
> +
> +struct scmi_imx_bbm {
> +	struct scmi_protocol_handle *ph;
> +	const struct scmi_imx_bbm_proto_ops *ops;
> +	struct notifier_block nb;
> +	int keycode;
> +	int keystate;  /* 1:pressed */
> +	bool suspended;
> +	struct delayed_work check_work;
> +	struct input_dev *input;
> +};
> +
> +static void scmi_imx_bbm_pwrkey_check_for_events(struct work_struct *work)
> +{
> +	struct scmi_imx_bbm *bbnsm = container_of(to_delayed_work(work),
> +						  struct scmi_imx_bbm, check_work);
> +	struct scmi_protocol_handle *ph = bbnsm->ph;
> +	struct input_dev *input = bbnsm->input;
> +	u32 state = 0;
> +	int ret;
> +
> +	ret = bbnsm->ops->button_get(ph, &state);
> +	if (ret) {
> +		pr_err("%s: %d\n", __func__, ret);
> +		return;
> +	}
> +
> +	pr_debug("%s: state: %d, keystate %d\n", __func__, state, bbnsm->keystate);
> +
> +	/* only report new event if status changed */
> +	if (state ^ bbnsm->keystate) {
> +		bbnsm->keystate = state;
> +		input_event(input, EV_KEY, bbnsm->keycode, state);
> +		input_sync(input);
> +		pm_relax(bbnsm->input->dev.parent);
> +		pr_debug("EV_KEY: %x\n", bbnsm->keycode);
> +	}
> +
> +	/* repeat check if pressed long */
> +	if (state)
> +		schedule_delayed_work(&bbnsm->check_work, msecs_to_jiffies(REPEAT_INTERVAL));
> +}
> +
> +static int scmi_imx_bbm_pwrkey_event(struct scmi_imx_bbm *bbnsm)
> +{
> +	struct input_dev *input = bbnsm->input;
> +
> +	pm_wakeup_event(input->dev.parent, 0);
> +
> +	/*
> +	 * Directly report key event after resume to make no key press
> +	 * event is missed.
> +	 */
> +	if (READ_ONCE(bbnsm->suspended)) {
> +		bbnsm->keystate = 1;
> +		input_event(input, EV_KEY, bbnsm->keycode, 1);
> +		input_sync(input);
> +		WRITE_ONCE(bbnsm->suspended, false);
> +	}
> +
> +	schedule_delayed_work(&bbnsm->check_work, msecs_to_jiffies(DEBOUNCE_TIME));
> +
> +	return 0;
> +}
> +
> +static void scmi_imx_bbm_pwrkey_act(void *pdata)
> +{
> +	struct scmi_imx_bbm *bbnsm = pdata;
> +
> +	cancel_delayed_work_sync(&bbnsm->check_work);
> +}
> +
> +static int scmi_imx_bbm_key_notifier(struct notifier_block *nb, unsigned long event, void *data)
> +{
> +	struct scmi_imx_bbm *bbnsm = container_of(nb, struct scmi_imx_bbm, nb);
> +	struct scmi_imx_bbm_notif_report *r = data;
> +
> +	if (r->is_button) {
> +		pr_debug("BBM Button Power key pressed\n");
> +		scmi_imx_bbm_pwrkey_event(bbnsm);
> +	} else {
> +		/* Should never reach here */
> +		pr_err("Unexpected BBM event: %s\n", __func__);
> +	}
> +
> +	return 0;
> +}
> +
> +static int scmi_imx_bbm_pwrkey_init(struct scmi_device *sdev)
> +{
> +	const struct scmi_handle *handle = sdev->handle;
> +	struct device *dev = &sdev->dev;
> +	struct scmi_imx_bbm *bbnsm = dev_get_drvdata(dev);
> +	struct input_dev *input;
> +	int ret;
> +
> +	if (device_property_read_u32(dev, "linux,code", &bbnsm->keycode)) {
> +		bbnsm->keycode = KEY_POWER;
> +		dev_warn(dev, "key code is not specified, using default KEY_POWER\n");
> +	}
> +
> +	INIT_DELAYED_WORK(&bbnsm->check_work, scmi_imx_bbm_pwrkey_check_for_events);
> +
> +	input = devm_input_allocate_device(dev);
> +	if (!input) {
> +		dev_err(dev, "failed to allocate the input device for SCMI IMX BBM\n");
> +		return -ENOMEM;
> +	}
> +
> +	input->name = dev_name(dev);
> +	input->phys = "bbnsm-pwrkey/input0";
> +	input->id.bustype = BUS_HOST;
> +
> +	input_set_capability(input, EV_KEY, bbnsm->keycode);
> +
> +	ret = devm_add_action_or_reset(dev, scmi_imx_bbm_pwrkey_act, bbnsm);
> +	if (ret) {
> +		dev_err(dev, "failed to register remove action\n");
> +		return ret;
> +	}
> +
> +	bbnsm->input = input;
> +
> +	bbnsm->nb.notifier_call = &scmi_imx_bbm_key_notifier;
> +	ret = handle->notify_ops->devm_event_notifier_register(sdev, SCMI_PROTOCOL_IMX_BBM,
> +							       SCMI_EVENT_IMX_BBM_BUTTON,
> +							       NULL, &bbnsm->nb);
> +
> +	if (ret)
> +		dev_err(dev, "Failed to register BBM Button Events %d:", ret);
> +
> +	ret = input_register_device(input);
> +	if (ret) {
> +		dev_err(dev, "failed to register input device\n");
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int scmi_imx_bbm_key_probe(struct scmi_device *sdev)
> +{
> +	const struct scmi_handle *handle = sdev->handle;
> +	struct device *dev = &sdev->dev;
> +	struct scmi_protocol_handle *ph;
> +	struct scmi_imx_bbm *bbnsm;
> +	int ret;
> +
> +	if (!handle)
> +		return -ENODEV;
> +
> +	bbnsm = devm_kzalloc(dev, sizeof(*bbnsm), GFP_KERNEL);
> +	if (!bbnsm)
> +		return -ENOMEM;
> +
> +	bbnsm->ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_IMX_BBM, &ph);
> +	if (IS_ERR(bbnsm->ops))
> +		return PTR_ERR(bbnsm->ops);
> +
> +	bbnsm->ph = ph;
> +
> +	device_init_wakeup(dev, true);
> +
> +	dev_set_drvdata(dev, bbnsm);
> +
> +	ret = scmi_imx_bbm_pwrkey_init(sdev);
> +	if (ret)
> +		device_init_wakeup(dev, false);
> +
> +	return ret;
> +}
> +
> +static void scmi_imx_bbm_key_remove(struct scmi_device *sdev)
> +{
> +	struct device *dev = &sdev->dev;
> +	struct scmi_imx_bbm *bbnsm = dev_get_drvdata(dev);
> +
> +	device_init_wakeup(dev, false);
> +
> +	cancel_delayed_work_sync(&bbnsm->check_work);
> +}
> +

..so in v6 I asked you to add a cancel_delayed_work_sync() on the
removal path, BUT I missed, my bad, that indeed above there was already
a call to cancel_delayed_work_sync() associated to a
devm_add_action_or_reset....so now we have 2....also you should try not
to mix devm_add_action_or_reset and plain .remove methods..use one or
the other.

Thanks,
Cristian