Re: [PATCH v3 1/6] soundwire: bus: Allow SoundWire peripherals to register IRQ handlers

From: andy.shevchenko@gmail.com
To: Charles Keepax <ckeepax@opensource.cirrus.com>
Cc: broonie@kernel.org, lee@kernel.org,
	krzysztof.kozlowski+dt@linaro.org, linus.walleij@linaro.org,
	vkoul@kernel.org, robh+dt@kernel.org, conor+dt@kernel.org,
	lgirdwood@gmail.com, yung-chuan.liao@linux.intel.com,
	sanyog.r.kale@intel.com, pierre-louis.bossart@linux.intel.com,
	alsa-devel@alsa-project.org, patches@opensource.cirrus.com,
	devicetree@vger.kernel.org, linux-gpio@vger.kernel.org,
	linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v3 1/6] soundwire: bus: Allow SoundWire peripherals to register IRQ handlers
Date: Fri, 16 Jun 2023 01:14:53 +0300	[thread overview]
Message-ID: <ZIuNXQIB3j6YjYa7@surfacebook> (raw)
In-Reply-To: <20230605125504.2570158-2-ckeepax@opensource.cirrus.com>

Mon, Jun 05, 2023 at 01:54:59PM +0100, Charles Keepax kirjoitti:
> From: Lucas Tanure <tanureal@opensource.cirrus.com>
> 
> Currently the in-band alerts for SoundWire peripherals can only
> be communicated to the driver through the interrupt_callback
> function. This however is slightly inconvient for devices that wish to
> share IRQ handling code between SoundWire and I2C/SPI, the later would
> normally register an IRQ handler with the IRQ subsystem. However there
> is no reason the SoundWire in-band IRQs can not also be communicated
> as an actual IRQ to the driver.
> 
> Add support for SoundWire peripherals to register a normal IRQ handler
> to receive SoundWire in-band alerts, allowing code to be shared across
> control buses. Note that we allow users to use both the
> interrupt_callback and the IRQ handler, this is useful for devices which
> must clear additional chip specific SoundWire registers that are not a
> part of the normal IRQ flow, or the SoundWire specification.

...

> +	bus->irq_chip.name = dev_name(bus->dev);
> +	bus->domain = irq_domain_add_linear(NULL, SDW_MAX_DEVICES, &sdw_domain_ops, bus);

I'm wondering why you are not using existing fwnode, if any
(e.g. from parent device).

> +	if (!bus->domain) {
> +		dev_err(bus->dev, "Failed to add IRQ domain\n");
> +		return -EINVAL;
> +	}

-- 
With Best Regards,
Andy Shevchenko