Re: [PATCH v3 24/24] platform/chrome: cros_ec: Use PM subsystem to manage wakeirq

From: Andy Shevchenko
Date: Wed Dec 27 2023 - 12:35:17 EST


On Tue, Dec 26, 2023 at 12:21:28PM -0700, Mark Hasemeyer wrote:
> The cros ec driver is manually managing the wake IRQ by calling
> enable_irq_wake()/disable_irq_wake() during suspend/resume.
>
> Modify the driver to use the power management subsystem to manage the
> wakeirq.
>
> Rather than assuming that the IRQ is wake capable, use the underlying
> firmware/device tree to determine whether or not to enable it as a wake
> source. Some Chromebooks rely solely on the ec_sync pin to wake the AP
> but do not specify the interrupt as wake capable in the ACPI _CRS. For
> LPC/ACPI based systems a DMI quirk is introduced listing boards whose
> firmware should not be trusted to provide correct wake capable values.
> For device tree base systems, it is not an issue as the relevant device
> tree entries have been updated and DTS is built from source for each
> ChromeOS update.

...

> acpi_status status;
> struct cros_ec_device *ec_dev;
> + struct resource irqres;

struct resource irqres = {};

?

> u8 buf[2] = {};
> int irq, ret;

...

> - irq = platform_get_irq_optional(pdev, 0);
> - if (irq > 0)
> + irq = platform_get_irq_resource_optional(pdev, 0, &irqres);
> + if (irq > 0) {
> ec_dev->irq = irq;
> - else if (irq != -ENXIO) {
> + if (should_force_irq_wake_capable())
> + ec_dev->irq_wake = true;
> + else
> + ec_dev->irq_wake = irqres.flags & IORESOURCE_IRQ_WAKECAPABLE;
> + } else if (irq != -ENXIO) {
> dev_err(dev, "couldn't retrieve IRQ number (%d)\n", irq);
> return irq;
> }

Still I do not like ambiguity behind irq > 0 vs. irqres.start.

For this, and if needed others, return plain error.
Seems I gave the tag for the previous patch, consider
that tag conditional (it seems I missed this).

...

> u16 proto_version;
> void *priv;
> int irq;
> + bool irq_wake;
> u8 *din;
> u8 *dout;
> int din_size;
> int dout_size;
> - bool wake_enabled;
> bool suspended;
> int (*cmd_xfer)(struct cros_ec_device *ec,
> struct cros_ec_command *msg);

Have you run pahole on this (before and after)?

--
With Best Regards,
Andy Shevchenko