[PATCH 2/4] input: bbnsm_pwrkey: Add bbnsm power key support

Jacky Bai ping.bai at nxp.com
Wed Nov 23 01:39:57 PST 2022


> Subject: Re: [PATCH 2/4] input: bbnsm_pwrkey: Add bbnsm power key
> support
> 
> Hi Jacky,
> 
> On Mon, Nov 21, 2022 at 02:51:42PM +0800, Jacky Bai wrote:
> > The ON/OFF logic inside the BBNSM allows for connecting directly into
> > a PMIC or other voltage regulator device. The module has an button
> > input signal and a wakeup request input signal. It also has two
> > interrupts (set_pwr_off_irq and set_pwr_on_irq) and an active-low PMIC
> > enable (pmic_en_b) output.
> >
> > Add the power key support for the ON/OFF button function found in
> > BBNSM module.
> >
> > Signed-off-by: Jacky Bai <ping.bai at nxp.com>
> > Reviewed-by: Peng Fan <peng.fan at nxp.com>
> > ---
> >  drivers/input/keyboard/Kconfig        |  11 ++
> >  drivers/input/keyboard/Makefile       |   1 +
> >  drivers/input/keyboard/bbnsm_pwrkey.c | 196
> > ++++++++++++++++++++++++++
> >  3 files changed, 208 insertions(+)
> >  create mode 100644 drivers/input/keyboard/bbnsm_pwrkey.c
> >
> > diff --git a/drivers/input/keyboard/Kconfig
> > b/drivers/input/keyboard/Kconfig index 00292118b79b..8efcd95492b3
> > 100644
> > --- a/drivers/input/keyboard/Kconfig
> > +++ b/drivers/input/keyboard/Kconfig
> > @@ -456,6 +456,17 @@ config KEYBOARD_SNVS_PWRKEY
> >  	  To compile this driver as a module, choose M here; the
> >  	  module will be called snvs_pwrkey.
> >
> > +config KEYBOARD_BBNSM_PWRKEY
> > +	tristate "NXP BBNSM Power Key Driver"
> > +	depends on ARCH_MXC || COMPILE_TEST
> > +	depends on OF
> > +	help
> > +	  This is the bbnsm powerkey driver for the NXP i.MX application
> > +	  processors.
> > +
> > +	  To compile this driver as a module, choose M here; the
> > +	  module will be called bbnsm_pwrkey.
> > +
> >  config KEYBOARD_IMX
> >  	tristate "IMX keypad support"
> >  	depends on ARCH_MXC || COMPILE_TEST
> > diff --git a/drivers/input/keyboard/Makefile
> > b/drivers/input/keyboard/Makefile index 5f67196bb2c1..0bc101e004ae
> > 100644
> > --- a/drivers/input/keyboard/Makefile
> > +++ b/drivers/input/keyboard/Makefile
> > @@ -62,6 +62,7 @@ obj-$(CONFIG_KEYBOARD_QT2160)		+=
> qt2160.o
> >  obj-$(CONFIG_KEYBOARD_SAMSUNG)		+= samsung-keypad.o
> >  obj-$(CONFIG_KEYBOARD_SH_KEYSC)		+= sh_keysc.o
> >  obj-$(CONFIG_KEYBOARD_SNVS_PWRKEY)	+= snvs_pwrkey.o
> > +obj-$(CONFIG_KEYBOARD_BBNSM_PWRKEY)	+= bbnsm_pwrkey.o
> >  obj-$(CONFIG_KEYBOARD_SPEAR)		+= spear-keyboard.o
> >  obj-$(CONFIG_KEYBOARD_STMPE)		+= stmpe-keypad.o
> >  obj-$(CONFIG_KEYBOARD_STOWAWAY)		+= stowaway.o
> > diff --git a/drivers/input/keyboard/bbnsm_pwrkey.c
> > b/drivers/input/keyboard/bbnsm_pwrkey.c
> > new file mode 100644
> > index 000000000000..288ee6844000
> > --- /dev/null
> > +++ b/drivers/input/keyboard/bbnsm_pwrkey.c

...

> > +
> > +static void bbnsm_pwrkey_check_for_events(struct timer_list *t) {
> > +	struct bbnsm_pwrkey *bbnsm = from_timer(bbnsm, t, check_timer);
> > +	struct input_dev *input = bbnsm->input;
> > +	u32 state;
> > +
> > +	regmap_read(bbnsm->regmap, BBNSM_EVENTS, &state);
> 
> Can this fail?

Should no chance to fail. Any more tips?

> 
> > +
> > +	state = state & BBNSM_BTN_PRESSED ? 1 : 0;
> > +
> > +	/* 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);
> > +	}
> > +
> > +	/* repeat check if pressed long */
> > +	if (state) {
> > +		mod_timer(&bbnsm->check_timer,
> > +			  jiffies + msecs_to_jiffies(REPEAT_INTERVAL));
> > +	}
> 
> So interrupt is only generated once when key is pressed, but not on release?
> 

Yes, at lease from my test, this interrupt can only be triggered when pressed.

> > +}
> > +
> > +static irqreturn_t bbnsm_pwrkey_interrupt(int irq, void *dev_id) {
> > +	struct platform_device *pdev = dev_id;
> > +	struct bbnsm_pwrkey *bbnsm = platform_get_drvdata(pdev);
> > +	struct input_dev *input = bbnsm->input;
> > +	u32 event;
> > +
> > +	regmap_read(bbnsm->regmap, BBNSM_EVENTS, &event);
> > +	if (event & BBNSM_BTN_OFF)
> > +		mod_timer(&bbnsm->check_timer, jiffies +
> msecs_to_jiffies(DEBOUNCE_TIME));
> > +	else
> > +		return IRQ_NONE;
> > +
> > +	pm_wakeup_event(input->dev.parent, 0);
> > +
> > +	/* clear PWR OFF */
> > +	regmap_write(bbnsm->regmap, BBNSM_EVENTS, BBNSM_BTN_OFF);
> > +
> > +	return IRQ_HANDLED;
> > +}
> > +
> > +static void bbnsm_pwrkey_act(void *pdata) {
> > +	struct bbnsm_pwrkey *bbnsm = pdata;
> > +
> > +	del_timer_sync(&bbnsm->check_timer);
> > +}
> > +
> > +static int bbnsm_pwrkey_probe(struct platform_device *pdev) {
> > +	struct bbnsm_pwrkey *bbnsm;
> > +	struct input_dev *input;
> > +	struct device_node *np = pdev->dev.of_node;
> > +	int error;
> > +
> > +	bbnsm = devm_kzalloc(&pdev->dev, sizeof(*bbnsm), GFP_KERNEL);
> > +	if (!bbnsm)
> > +		return -ENOMEM;
> > +
> > +	bbnsm->regmap =
> syscon_regmap_lookup_by_phandle(pdev->dev.of_node, "regmap");
> > +	if (IS_ERR(bbnsm->regmap)) {
> > +		dev_err(&pdev->dev, "bbnsm pwerkey get regmap failed\n");
> > +		return PTR_ERR(bbnsm->regmap);
> > +	}
> > +
> > +	if (of_property_read_u32(np, "linux,code", &bbnsm->keycode)) {
> 
> Please use device_property_read_u32() here.

Ok, will fix in V2.

> 
> > +		bbnsm->keycode = KEY_POWER;
> > +		dev_warn(&pdev->dev, "KEY_POWER without setting in dts\n");
> > +	}
> > +
> > +	bbnsm->irq = platform_get_irq(pdev, 0);
> > +	if (bbnsm->irq < 0)
> > +		return -EINVAL;
> > +
> > +	/* config the BBNSM power related register */
> > +	regmap_update_bits(bbnsm->regmap, BBNSM_CTRL, BBNSM_DP_EN,
> > +BBNSM_DP_EN);
> > +
> > +	/* clear the unexpected interrupt before driver ready */
> > +	regmap_write_bits(bbnsm->regmap, BBNSM_EVENTS,
> BBNSM_PWRKEY_EVENTS,
> > +BBNSM_PWRKEY_EVENTS);
> > +
> > +	timer_setup(&bbnsm->check_timer, bbnsm_pwrkey_check_for_events,
> 0);
> > +
> > +	input = devm_input_allocate_device(&pdev->dev);
> > +	if (!input) {
> > +		dev_err(&pdev->dev, "failed to allocate the input device\n");
> > +		error = -ENOMEM;
> > +		goto error_probe;
> 
> Please return directly here and below, since there is not explicit cleanup.
> 

Thx, will fix in V2.

BR

> > +	}
> > +
> > +	input->name = pdev->name;
> > +	input->phys = "bbnsm-pwrkey/input0";
> > +	input->id.bustype = BUS_HOST;
> > +
> > +	input_set_capability(input, EV_KEY, bbnsm->keycode);
> > +
> > +	/* input customer action to cancel release timer */
> > +	error = devm_add_action(&pdev->dev, bbnsm_pwrkey_act, bbnsm);
> > +	if (error) {
> > +		dev_err(&pdev->dev, "failed to register remove action\n");
> > +		goto error_probe;
> > +	}
> > +
> > +	bbnsm->input = input;
> > +	platform_set_drvdata(pdev, bbnsm);
> > +
> > +	error = devm_request_irq(&pdev->dev, bbnsm->irq,
> bbnsm_pwrkey_interrupt,
> > +			       IRQF_SHARED, pdev->name, pdev);
> > +	if (error) {
> > +		dev_err(&pdev->dev, "interrupt not available.\n");
> > +		goto error_probe;
> > +	}
> > +
> > +	error = input_register_device(input);
> > +	if (error < 0) {
> > +		dev_err(&pdev->dev, "failed to register input device\n");
> > +		goto error_probe;
> > +	}
> > +
> > +	device_init_wakeup(&pdev->dev, true);
> > +	error = dev_pm_set_wake_irq(&pdev->dev, bbnsm->irq);
> > +	if (error)
> > +		dev_err(&pdev->dev, "irq wake enable failed.\n");
> > +
> > +	return 0;
> > +
> > +error_probe:
> > +	return error;
> > +}
> > +
> > +static const struct of_device_id bbnsm_pwrkey_ids[] = {
> > +	{ .compatible = "nxp,bbnsm-pwrkey" },
> > +	{ /* sentinel */ }
> > +};
> > +MODULE_DEVICE_TABLE(of, bbnsm_pwrkey_ids);
> > +
> > +static struct platform_driver bbnsm_pwrkey_driver = {
> > +	.driver = {
> > +		.name = "bbnsm_pwrkey",
> > +		.of_match_table = bbnsm_pwrkey_ids,
> > +	},
> > +	.probe = bbnsm_pwrkey_probe,
> > +};
> > +module_platform_driver(bbnsm_pwrkey_driver);
> > +
> > +MODULE_AUTHOR("Jacky Bai <ping.bai at nxp.com>");
> > +MODULE_DESCRIPTION("NXP bbnsm power key Driver");
> > +MODULE_LICENSE("GPL");
> > --
> > 2.37.1
> >
> 
> Thanks.
> 
> --
> Dmitry



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