Re: [PATCH v3 2/3] spi: Add Amlogic SPISG driver

[Xianwei Zhao]

Hi Krzysztof,
   Thanks for your reply.

On 2025/6/23 17:17, Krzysztof Kozlowski wrote:
> [ EXTERNAL EMAIL ]
>
> On 23/06/2025 10:53, Xianwei Zhao via B4 Relay wrote:
> > From: Sunny Luo <sunny.luo@xxxxxxxxxxx>
> >
> > Introduced support for the new SPI IP (SPISG) driver. The SPISG is
> > a communication-oriented SPI controller from Amlogic,supporting
> > three operation modes: PIO, block DMA, and scatter-gather DMA.
> >
> > Signed-off-by: Sunny Luo <sunny.luo@xxxxxxxxxxx>
> > Signed-off-by: Xianwei Zhao <xianwei.zhao@xxxxxxxxxxx>
> > ---
> >   drivers/spi/Kconfig             |   9 +
> >   drivers/spi/Makefile            |   1 +
> >   drivers/spi/spi-amlogic-spisg.c | 876 ++++++++++++++++++++++++++++++++++++++++
> >   3 files changed, 886 insertions(+)
> >
> > diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> > index c51da3fc3604..e11341df2ecf 100644
> > --- a/drivers/spi/Kconfig
> > +++ b/drivers/spi/Kconfig
> > @@ -99,6 +99,15 @@ config SPI_AMLOGIC_SPIFC_A1
> >          This enables master mode support for the SPIFC (SPI flash
> >          controller) available in Amlogic A1 (A113L SoC).
> >
> > +config SPI_AMLOGIC_SPISG
> > +     tristate "Amlogic SPISG controller"
> > +     depends on COMMON_CLK
> > +     depends on ARCH_MESON || COMPILE_TEST
> > +     help
> > +       This enables master mode support for the SPISG (SPI scatter-gather
> > +       communication controller), which is available on platforms such as
> > +       Amlogic A4 SoCs.
> > +
> >   config SPI_APPLE
> >        tristate "Apple SoC SPI Controller platform driver"
> >        depends on ARCH_APPLE || COMPILE_TEST
> > diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> > index 4ea89f6fc531..b74e3104d71f 100644
> > --- a/drivers/spi/Makefile
> > +++ b/drivers/spi/Makefile
> > @@ -20,6 +20,7 @@ obj-$(CONFIG_SPI_ALTERA)            += spi-altera-platform.o
> >   obj-$(CONFIG_SPI_ALTERA_CORE)                += spi-altera-core.o
> >   obj-$(CONFIG_SPI_ALTERA_DFL)         += spi-altera-dfl.o
> >   obj-$(CONFIG_SPI_AMLOGIC_SPIFC_A1)   += spi-amlogic-spifc-a1.o
> > +obj-$(CONFIG_SPI_AMLOGIC_SPISG)              += spi-amlogic-spisg.o
> >   obj-$(CONFIG_SPI_APPLE)                      += spi-apple.o
> >   obj-$(CONFIG_SPI_AR934X)             += spi-ar934x.o
> >   obj-$(CONFIG_SPI_ARMADA_3700)                += spi-armada-3700.o
> > diff --git a/drivers/spi/spi-amlogic-spisg.c b/drivers/spi/spi-amlogic-spisg.c
> > new file mode 100644
> > index 000000000000..2f2982154d49
> > --- /dev/null
> > +++ b/drivers/spi/spi-amlogic-spisg.c
> > @@ -0,0 +1,876 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Driver for Amlogic SPI communication Scatter-Gather Controller
> > + *
> > + * Copyright (C) 2025 Amlogic, Inc. All rights reserved
> > + *
> > + * Author: Sunny Luo <sunny.luo@xxxxxxxxxxx>
> > + * Author: Xianwei Zhao <xianwei.zhao@xxxxxxxxxxx>
> > + */
> > +
> > +#include <linux/bitfield.h>
> > +#include <linux/clk.h>
> > +#include <linux/device.h>
> > +#include <linux/io.h>
> > +#include <linux/kernel.h>
> > +#include <linux/module.h>
> > +#include <linux/of.h>
> > +#include <linux/clk-provider.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/pm_domain.h>
>
> cacheflush
>
> > +#include <linux/platform_device.h>
> > +#include <linux/spi/spi.h>
> > +#include <linux/types.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/reset.h>
>
> So this you take to reset device... but your device does not have any
> resets! Just look at your binding.

Will add resets prop in binding.

> > +#include <linux/pinctrl/consumer.h>
> > +#include <linux/delay.h>
> > +#include <linux/cacheflush.h>
>
> Where do you use it?
Will remove it.
> > +#include <linux/regmap.h>
>
> Actually several other headers looks unused. I am not going to keep
> checking one by one - you should check and do not include irrelevant
> headers.

Will do.

> > +
> > +static int aml_spisg_probe(struct platform_device *pdev)
> > +{
> > +     struct spi_controller *ctlr;
> > +     struct spisg_device *spisg;
> > +     struct device *dev = &pdev->dev;
> > +     void __iomem *base;
> > +     int ret, irq;
> > +
> > +     const struct regmap_config aml_regmap_config = {
> > +             .reg_bits = 32,
> > +             .val_bits = 32,
> > +             .reg_stride = 4,
> > +             .max_register = SPISG_MAX_REG,
> > +     };
> > +
> > +     if (of_property_read_bool(dev->of_node, "slave"))
>
> "slave" is not a bool. You want to check for child presence, don't you?
> You need to use appropriate API for that otherwise you just add one of
> the issues which was being fixed recently.

The correct property name  should be "spi-salve". I will fix it.

> > +             ctlr = spi_alloc_target(dev, sizeof(*spisg));
> > +     else
> > +             ctlr = spi_alloc_host(dev, sizeof(*spisg));
> > +     if (!ctlr)
> > +             return dev_err_probe(dev, -ENOMEM, "controller allocation failed\n");
> > +
>
>
>
> > +
> > +static struct platform_driver amlogic_spisg_driver = {
> > +     .probe = aml_spisg_probe,
> > +     .remove = aml_spisg_remove,
> > +     .driver  = {
> > +             .name = "amlogic-spisg",
> > +             .of_match_table = of_match_ptr(amlogic_spisg_of_match),
>
> So now you will have warnings... drop of_match_ptr.

Will drop it.

> Both suggest you send us some old code, instead of working on something
> recent.

The following is the link of my first version:
https://lore.kernel.org/all/20250604-spisg-v1-0-5893dbe9d953@xxxxxxxxxxx/

> > +             .pm = &amlogic_spisg_pm_ops,
> > +     },
> > +};
> > +
> > +module_platform_driver(amlogic_spisg_driver);
> > +
> > +MODULE_DESCRIPTION("Amlogic SPI Scatter-Gather Controller driver");
> > +MODULE_AUTHOR("Sunny Luo <sunny.luo@xxxxxxxxxxx>");
> > +MODULE_LICENSE("GPL");
>
>
> Best regards,
> Krzysztof