Re: [PATCH v12] staging: fbtft: add tearing signal detect

From: Andy Shevchenko
Date: Thu Jan 28 2021 - 09:46:31 EST


On Thu, Jan 28, 2021 at 4:33 PM Andy Shevchenko
<andy.shevchenko@xxxxxxxxx> wrote:
> On Thu, Jan 28, 2021 at 2:58 PM Carlis <zhangxuezhi3@xxxxxxxxx> wrote:

...

> Taking all together you probably need to create a helper and use it
> inside init_display(), like
>
> static int init_tearing_effect_line(struct fbtft_par *par)
> {
> struct device *dev = par->info->device;
> struct gpio_desc *te;
> int irq, rc;
>
> te = gpiod_get_optional(dev, "te", GPIOD_IN);
> if (IS_ERR(te))
> return dev_err_probe(dev, PTR_ERR(te), "Failed to request
> te GPIO\n");

Sorry, here I missed the following:

/* Absence of TE IRQ is not critical */
if (!te)
return 0;

> irq = gpiod_to_irq(te); // this value you have to save in the
> driver's (per device) data structure.
>
> /* GPIO is locked as an IRQ, we may drop the reference */
> gpiod_put(te);

...and here:

if (irq < 0)
return irq;

> init_completion(&spi_panel_te); // should be in the (per device)
> data structure
> rc = devm_request_irq(dev, irq, spi_panel_te_handler,
> IRQF_TRIGGER_RISING, "TE_GPIO", par);
> if (rc)
> return dev_err_probe(dev, rc, "TE IRQ request failed.\n");
> disable_irq_nosync(irq);
> return irq;
> }

--
With Best Regards,
Andy Shevchenko