Re: [PATCH net] net: phy: Don't trigger state machine while in suspend

From: Andrew Lunn <andrew@lunn.ch>
To: Lukas Wunner <lukas@wunner.de>
Cc: "David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Eric Dumazet <edumazet@google.com>,
	Heiner Kallweit <hkallweit1@gmail.com>,
	Russell King <linux@armlinux.org.uk>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	netdev@vger.kernel.org,
	Steve Glendinning <steve.glendinning@shawell.net>,
	UNGLinuxDriver@microchip.com, Oliver Neukum <oneukum@suse.com>,
	Andre Edich <andre.edich@microchip.com>,
	Oleksij Rempel <linux@rempel-privat.de>,
	Martyn Welch <martyn.welch@collabora.com>,
	Gabriel Hojda <ghojda@yo2urs.ro>,
	Christoph Fritz <chf.fritz@googlemail.com>,
	Lino Sanfilippo <LinoSanfilippo@gmx.de>,
	Philipp Rosenberger <p.rosenberger@kunbus.com>,
	Ferry Toth <fntoth@gmail.com>,
	Krzysztof Kozlowski <krzk@kernel.org>,
	linux-samsung-soc@vger.kernel.org
Subject: Re: [PATCH net] net: phy: Don't trigger state machine while in suspend
Date: Mon, 6 Jun 2022 03:40:49 +0200	[thread overview]
Message-ID: <Yp1bIdwLjiLftWgW@lunn.ch> (raw)
In-Reply-To: <688f559346ea747d3b47a4d16ef8277e093f9ebe.1653556322.git.lukas@wunner.de>

> +	if (phy_interrupt_is_valid(phydev)) {
> +		phydev->irq_suspended = 0;
> +		synchronize_irq(phydev->irq);
> +
> +		/* Rerun interrupts which were postponed by phy_interrupt()
> +		 * because they occurred during the system sleep transition.
> +		 */
> +		if (phydev->irq_rerun) {
> +			phydev->irq_rerun = 0;
> +			enable_irq(phydev->irq);
> +			irq_wake_thread(phydev->irq, phydev);
> +		}
> +	}

As i said in a previous thread, PHY interrupts are generally level,
not edge. So when you call enable_irq(phydev->irq), doesn't it
immediately fire? You need to first call the handler, and then
re-enable the interrupt.

      Andrew