Re: [RESEND PATCH] gpio: omap: Fix lost edge interrupts

From: Santosh Shilimkar
Date: Tue Oct 03 2017 - 12:41:24 EST




On 10/3/2017 9:17 AM, Grygorii Strashko wrote:
Now acking of edge irqs happens the following way:
- omap_gpio_irq_handler
- "isr" = read irq status
- omap_clear_gpio_irqbank(bank, isr_saved & ~level_mask);
^ clear edge status, so irq can be accepted
- loop while "isr"
generic_handle_irq()
- handle_edge_irq()
- desc->irq_data.chip->irq_ack(&desc->irq_data);
- omap_gpio_ack_irq()
it might be that at this moment edge IRQ was triggered again and it will be
cleared and IRQ will be lost.

Use handle_simple_irq and clear edge interrupts early without disabling them in
omap_gpio_irq_handler to avoid loosing interrupts.

[1] https://urldefense.proofpoint.com/v2/url?u=https-3A__marc.info_-3Fl-3Dlinux-2Domap-26m-3D149004465313534-26w-3D2&d=DwIBAg&c=RoP1YumCXCgaWHvlZYR8PQcxBKCX5YTpkKY057SbK10&r=XBn1JQGPwR8CsE7xpP3wPlG6DQU7qw8ym65xieNZ4hY&m=-JZAaXlsRBFYNqtZ-2KOemoupa4pL7ka9D3wKn6hX9o&s=c-1XuQUl3_1uYedoNhmY70xCO3fAftWB7cmFxgyC3j4&e=
Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
Signed-off-by: Ladislav Michl <ladis@xxxxxxxxxxxxxx>
---
Resend with proper cc list.

This was one of the concern I was thinking when GPIO IRQ conversion
was done. Grygorii since you did that conversion, can you please
check since I see now that the irq code is becoming increasingly
complex.

Regards,
Santosh