Re: [PATCH 05/10] spi: spi-dw-mmio: Spin off MSCC platforms into spi-dw-mchp

From: Lars Povlsen
Date: Tue May 19 2020 - 08:05:28 EST


On 13/05/20 16:18, Mark Brown wrote:
> Date: Wed, 13 May 2020 16:18:11 +0100
> From: Mark Brown <broonie@xxxxxxxxxx>
> To: Lars Povlsen <lars.povlsen@xxxxxxxxxxxxx>
> Cc: SoC Team <soc@xxxxxxxxxx>, Microchip Linux Driver Support
> <UNGLinuxDriver@xxxxxxxxxxxxx>, linux-spi@xxxxxxxxxxxxxxx,
> devicetree@xxxxxxxxxxxxxxx, linux-kernel@xxxxxxxxxxxxxxx,
> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx, Alexandre Belloni
> <alexandre.belloni@xxxxxxxxxxx>
> Subject: Re: [PATCH 05/10] spi: spi-dw-mmio: Spin off MSCC platforms into
> spi-dw-mchp
> User-Agent: Mutt/1.10.1 (2018-07-13)
>
> On Wed, May 13, 2020 at 04:00:26PM +0200, Lars Povlsen wrote:
>
> > +config SPI_DW_MCHP
> > + tristate "Memory-mapped io interface driver using DW SPI core of MSCC SoCs"
> > + default y if ARCH_SPARX5
> > + default y if SOC_VCOREIII
>
> Why the default ys?

The SoC will typically boot from SPI... But its not a requirement per
se. I will remove it.

>
> > +++ b/drivers/spi/Makefile
> > @@ -37,6 +37,7 @@ obj-$(CONFIG_SPI_DAVINCI) += spi-davinci.o
> > obj-$(CONFIG_SPI_DLN2) += spi-dln2.o
> > obj-$(CONFIG_SPI_DESIGNWARE) += spi-dw.o
> > obj-$(CONFIG_SPI_DW_MMIO) += spi-dw-mmio.o
> > +obj-$(CONFIG_SPI_DW_MCHP) += spi-dw-mchp.o
> > obj-$(CONFIG_SPI_DW_PCI) += spi-dw-midpci.o
> > spi-dw-midpci-objs := spi-dw-pci.o spi-dw-mid.o
> > obj-$(CONFIG_SPI_EFM32) += spi-efm32.o
>
> Please keep the file alphabetically sorted.
>

Noted.

> > +++ b/drivers/spi/spi-dw-mchp.c
> > @@ -0,0 +1,232 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Memory-mapped interface driver for MSCC SoCs
> > + *
>
> Please make the entire comment a C++ one so things look more
> intentional.

Sure, I can do that. The presented form matches that of the other
spi-dw-* drivers, but I can see other using // blocks. Ack.

>
> > +#define MAX_CS 4
>
> This should be namespaced.

Ack.

>
> > + rx_sample_dly = 0;
> > + device_property_read_u32(&pdev->dev, "spi-rx-delay-us", &rx_sample_dly);
> > + dws->rx_sample_dly = DIV_ROUND_UP(rx_sample_dly,
> > + (dws->max_freq / 1000000));
>
> If this is a standard feature of the DesignWare IP why parse it here and
> not in the generic code?

This is a standard feature of the DesignWare IP, so good suggestion. I
will arrange with Serge.

Thank you for your comments!

---Lars