On Thu, 30 Apr 2020, Guru Das Srinagesh wrote:
> On Wed, Apr 29, 2020 at 08:50:10AM +0100, Lee Jones wrote:
> > On Tue, 28 Apr 2020, Guru Das Srinagesh wrote:
> >
> > > The Qualcomm Technologies, Inc. I2C PMIC Controller is used by
> > > multi-function PMIC devices which communicate over the I2C bus. The
> > > controller enumerates all child nodes as platform devices, and
> > > instantiates a regmap interface for them to communicate over the I2C
> > > bus.
> > >
> > > The controller also controls interrupts for all of the children platform
> > > devices. The controller handles the summary interrupt by deciphering
> > > which peripheral triggered the interrupt, and which of the peripheral
> > > interrupts were triggered. Finally, it calls the interrupt handlers for
> > > each of the virtual interrupts that were registered.
> > >
> > > Nicholas Troast is the original author of this driver.
> > >
> > > Signed-off-by: Guru Das Srinagesh <gurus@xxxxxxxxxxxxxx>
> > > ---
> > > drivers/mfd/Kconfig | 11 +
> > > drivers/mfd/Makefile | 1 +
> > > drivers/mfd/qcom-i2c-pmic.c | 737 ++++++++++++++++++++++++++++++++++++++++++++
> >
> > The vast majority of this driver deals with IRQ handling. Why can't
> > this be split out into its own IRQ Chip driver and moved to
> > drivers/irqchip?
>
> There appear to be quite a few in-tree MFD drivers that register IRQ
> controllers, like this driver does:
>
> $ grep --exclude-dir=.git -rnE "irq_domain_(add|create).+\(" drivers/mfd | wc -l
> 23
>
> As a further example, drivers/mfd/stpmic1.c closely resembles this
> driver in that it uses both devm_regmap_add_irq_chip() as well as
> devm_of_platform_populate().
>
> As such, it seems like this driver is in line with some of the
> architectural choices that have been accepted in already-merged drivers.
> Could you please elaborate on your concerns?
It is true that *basic* IRQ domain support has been added to these
drivers in the past. However, IMHO the support added to this driver
goes beyond those realms such that it would justify a driver of its
own.
--
Lee Jones [李琼斯]
Linaro Services Technical Lead
Linaro.org │ Open source software for ARM SoCs
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