Re: [PATCH v6 2/2] spi: loongson: add bus driver for the loongson spi controller

[zhuyinbo <zhuyinbo@loongson.cn>]

在 2023/4/2 下午6:04, Krzysztof Kozlowski 写道:
> On 01/04/2023 11:56, Yinbo Zhu wrote:
>> This bus driver supports the Loongson spi hardware controller in the
>> Loongson platforms and supports to use DTS and PCI framework to
>> register spi device resources.
>>
>> Signed-off-by: Yinbo Zhu <zhuyinbo@loongson.cn>
>> ---
> 
> 
> ...
> 
>> +
>> +#include <linux/init.h>
>> +#include <linux/module.h>
>> +#include <linux/kernel.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/delay.h>
>> +#include <linux/err.h>
>> +#include <linux/spi/spi.h>
>> +#include <linux/clk.h>
>> +#include <linux/io.h>
>> +
>> +#include "spi-loongson.h"
>> +
>> +static inline void loongson_spi_write_reg(struct loongson_spi *spi, unsigned char reg,
>> +					  unsigned char data)
>> +{
>> +	writeb(data, spi->base + reg);
> 
> This wrapper does not simplify anything.
Mark seems to have other viewpoint.
> 
>> +}
>> +
>> +static inline char loongson_spi_read_reg(struct loongson_spi *spi, unsigned char reg)
>> +{
>> +	return readb(spi->base + reg);
> 
> Neither this one.
> 
>> +}
>> +
>> +static void loongson_spi_set_cs(struct spi_device *spi, bool val)
>> +{
>> +	int cs;
>> +	struct loongson_spi *loongson_spi = spi_master_get_devdata(spi->master);
>> +
> 
> (...)
> 
>> +
>> +static int __init loongson_spi_pci_init(void)
>> +{
>> +	int ret;
>> +
>> +	ret = pci_register_driver(&loongson_spi_pci_driver);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return 0;
>> +}
>> +
>> +static void __exit loongson_spi_pci_exit(void)
>> +{
>> +	pci_unregister_driver(&loongson_spi_pci_driver);
>> +}
>> +
>> +module_init(loongson_spi_pci_init);
>> +module_exit(loongson_spi_pci_exit);
> 
> module_xxx_driver?
okay, I got it.
> 
>> +
>> +MODULE_DESCRIPTION("Loongson spi pci driver");
>> +MODULE_LICENSE("GPL");
>> diff --git a/drivers/spi/spi-loongson-plat.c b/drivers/spi/spi-loongson-plat.c
>> new file mode 100644
>> index 000000000000..8f4aa70168f3
>> --- /dev/null
>> +++ b/drivers/spi/spi-loongson-plat.c
>> @@ -0,0 +1,66 @@
>> +// SPDX-License-Identifier: GPL-2.0+
>> +// Platform driver for Loongson SPI Support
>> +// Copyright (C) 2023 Loongson Technology Corporation Limited
>> +
>> +#include <linux/platform_device.h>
>> +#include <linux/of.h>
>> +
>> +#include "spi-loongson.h"
>> +
>> +static int loongson_spi_platform_probe(struct platform_device *pdev)
>> +{
>> +	struct device *dev = &pdev->dev;
>> +	struct resource *res;
>> +	int ret;
>> +
>> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>> +	if (res == NULL) {
>> +		dev_err(dev, "cannot get io resource memory\n");
>> +		return -ENOENT;
>> +	}
>> +
>> +	ret = loongson_spi_init_master(dev, res);
>> +	if (ret)
>> +		dev_err(dev, "failed to initialize master\n");
>> +
>> +	return ret;
>> +}
>> +
>> +static const struct of_device_id loongson_spi_id_table[] = {
>> +	{ .compatible = "loongson,ls2k-spi", },
>> +	{ }
>> +};
>> +MODULE_DEVICE_TABLE(of, loongson_spi_id_table);
>> +
>> +static struct platform_driver loongson_spi_plat_driver = {
>> +	.probe = loongson_spi_platform_probe,
>> +	.driver	= {
>> +		.name	= "loongson-spi",
>> +		.owner	= THIS_MODULE,
> 
> Really? We get rid of it years ago. I bet you did not run coccicheck,
> smatch, sparse...
okay, I got it, I will remove this line.

Thanks.
> 
>> +		.bus = &platform_bus_type,
>> +		.pm = &loongson_spi_dev_pm_ops,
>> +		.of_match_table = loongson_spi_id_table,
>> +	},
>> +};
>> +
>> +static int __init loongson_spi_plat_init(void)
>> +{
>> +	int ret;
>> +
>> +	ret = platform_driver_register(&loongson_spi_plat_driver);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return 0;
>> +}
>> +
>> +static void __exit loongson_spi_plat_exit(void)
>> +{
>> +	platform_driver_unregister(&loongson_spi_plat_driver);
>> +}
>> +
>> +module_init(loongson_spi_plat_init);
>> +module_exit(loongson_spi_plat_exit);
> 
> module_platform_driver.
okay, I will use it.
> 
>> +
>> +MODULE_DESCRIPTION("Loongson spi platform driver");
>> +MODULE_LICENSE("GPL");
>> diff --git a/drivers/spi/spi-loongson.h b/drivers/spi/spi-loongson.h
>> new file mode 100644
>> index 000000000000..44818340188d
>> --- /dev/null
>> +++ b/drivers/spi/spi-loongson.h
>> @@ -0,0 +1,41 @@
>> +/* SPDX-License-Identifier: GPL-2.0+ */
>> +/* Header File for Loongson SPI Driver. */
>> +/* Copyright (C) 2023 Loongson Technology Corporation Limited */
>> +
>> +#ifndef __LINUX_SPI_LOONGSON_H
>> +#define __LINUX_SPI_LOONGSON_H
>> +
>> +#define	LOONGSON_SPI_SPCR_REG	0x00
> 
> There is just one space after #define.
Mark seems to have other viewpoint.
> 
> 
> Best regards,
> Krzysztof
>