Re: [PATCH v2] pinctrl: qcom: Add irq_enable callback for msm gpio

From: Neeraj Upadhyay
Date: Tue Jun 25 2019 - 06:29:21 EST

On 6/25/19 2:28 PM, Linus Walleij wrote:
On Mon, Jun 17, 2019 at 11:35 AM Neeraj Upadhyay <neeraju@xxxxxxxxxxxxxx> wrote:

From: Srinivas Ramana <sramana@xxxxxxxxxxxxxx>

Introduce the irq_enable callback which will be same as irq_unmask
except that it will also clear the status bit before unmask.

This will help in clearing any erroneous interrupts that would
have got latched when the interrupt is not in use.

There may be devices like UART which can use the same gpio line
for data rx as well as a wakeup gpio when in suspend. The data that
was flowing on the line may latch the interrupt and when we enable
the interrupt before going to suspend, this would trigger the
unexpected interrupt. This change helps clearing the interrupt
so that these unexpected interrupts gets cleared.

Signed-off-by: Srinivas Ramana <sramana@xxxxxxxxxxxxxx>
Signed-off-by: Neeraj Upadhyay <neeraju@xxxxxxxxxxxxxx>
Overall this looks good to me, waiting for Bjorn's review.

Changes since v1:
- Extracted common code into __msm_gpio_irq_unmask().
Please don't name functions __like __that.

-static void msm_gpio_irq_unmask(struct irq_data *d)
+static void __msm_gpio_irq_unmask(struct irq_data *d, bool status_clear)
Instead of __unclear __underscore __semantic use something
really descriptive like

static void msm_gpio_irq_clear_irq()

That is what it does, right?

Is below ok? as it clears (if status_clear set) and then unmasks irq

static void msm_gpio_irq_clear_unmask()

Other than that it looks fine.

Linus Walleij

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