On Thu, 31 Aug 2017 20:33:55 +0200,
Dmitry Torokhov wrote:

Hi Takashi,

On Tue, Aug 22, 2017 at 07:57:09AM +0200, Takashi Iwai wrote:

quoted

This provides a new input driver for supporting the power button on
Dollar Cove TI PMIC, found on Cherrytrail-based devices.
The patch is based on the original work by Intel, found at:
  https://github.com/01org/ProductionKernelQuilts

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=193891
Signed-off-by: Takashi Iwai <redacted>
---
 drivers/input/keyboard/Kconfig        |  7 +++
 drivers/input/keyboard/Makefile       |  1 +
 drivers/input/keyboard/dc_ti_pwrbtn.c | 85 +++++++++++++++++++++++++++++++++++

Not sure if it ends up in drivers/input/keyboard, or drivers/input/misc/
(where most power buttons live) or in platform drivers, still a few
comments below.

Oh sorry, I forgot to put you to Cc after v2 patch.
Per Andy's suggestion, the driver was moved to drivers/platform/x86
now.  For v3 patchset, see the following thread.
  https://marc.info/?i=20170825134443.14843-1-tiwai%40suse.de

quoted

+config KEYBOARD_DC_TI_PWRBTN
+	tristate "Dollar Cove TI power button driver"
+	depends on INTEL_SOC_PMIC_DC_TI
+	help
+	  Say Y here fi you want to have a power button driver for
+	  Dollar Cove TI PMIC.

If keeping in input we customarily call out the module name (see a few
lines above).

I changed the driver and config names to follow the platform driver.

quoted

+#define DC_TI_SIRQ_REG		0x3
+#define SIRQ_PWRBTN_REL		(1 << 0)

BIT()?

OK.

quoted

+#define DRIVER_NAME "dc_ti_pwrbtn"
+
+static irqreturn_t dc_ti_pwrbtn_interrupt(int irq, void *dev_id)
+{
+	struct input_dev *pwrbtn_input = dev_id;
+	struct device *dev = pwrbtn_input->dev.parent;
+	struct regmap *regmap = dev_get_drvdata(dev);
+	int state;
+
+	if (!regmap_read(regmap, DC_TI_SIRQ_REG, &state)) {
+		dev_dbg(dev, "SIRQ_REG=0x%x\n", state);
+		state &= SIRQ_PWRBTN_REL;
+		input_event(pwrbtn_input, EV_KEY, KEY_POWER, !state);

Why not

		input_report_key(pwrbtn_input, KEY_POWER,
				 !(state & SIRQ_PWRBTN_REL));

Sounds better, indeed.

quoted

+		input_sync(pwrbtn_input);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int dc_ti_pwrbtn_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct intel_soc_pmic *pmic = dev_get_drvdata(dev->parent);
+	struct input_dev *pwrbtn_input;
+	int irq;
+	int ret;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return -EINVAL;

Why do you clobber return value? Simply return "irq".

OK.

quoted

+	pwrbtn_input = devm_input_allocate_device(dev);
+	if (!pwrbtn_input)
+		return -ENOMEM;
+	pwrbtn_input->name = pdev->name;
+	pwrbtn_input->phys = "dc-ti-power/input0";
+	pwrbtn_input->id.bustype = BUS_HOST;
+	pwrbtn_input->dev.parent = dev;

Not needed since devm_input_allocate_device() does it for us.

OK.

quoted

+	input_set_capability(pwrbtn_input, EV_KEY, KEY_POWER);
+	ret = input_register_device(pwrbtn_input);
+	if (ret)
+		return ret;

If staying in input, can we please call this variable err or error?

OK, I don't mind to change it.

quoted

+
+	dev_set_drvdata(dev, pmic->regmap);
+
+	ret = devm_request_threaded_irq(dev, irq, NULL, dc_ti_pwrbtn_interrupt,
+					0, KBUILD_MODNAME, pwrbtn_input);
+	if (ret)
+		return ret;
+
+	ret = enable_irq_wake(irq);
+	if (ret)
+		dev_warn(dev, "Can't enable IRQ as wake source: %d\n", ret);

We do not normally enable wake IRQs in probe, but instead do:

	device_init_wakeup(&pdev->dev, true);

in probe()

Right, this was already changed in the later version.
But...

and then check it in suspend/resume:

	if (device_may_wakeup(dev)) {
		err = enable_irq_wake(XXX->irq);
		if (!err)
			XXX->irq_wake_enabled = true;
	}

...

	if (XXX->irq_wake_enabled)
		disable_irq_wake(XXX->irq);

This allows userspace to inhibit wakeup, if needed.

... this wasn't.  Will put it.

Thank your for the review!


Takashi