Re: [PATCH V3 02/12] misc: xilinx-sdfec: add core driver

[Greg KH]

On Sat, Apr 27, 2019 at 11:04:56PM +0100, Dragan Cvetic wrote:
> +#define DRIVER_NAME "xilinx_sdfec"
> +#define DRIVER_VERSION "0.3"

Version means nothing with the driver in the kernel tree, please remove
it.

> +#define DRIVER_MAX_DEV BIT(MINORBITS)

Why this number?  Why limit yourself to any number?

> +
> +static struct class *xsdfec_class;

Do you really need your own class?

> +static atomic_t xsdfec_ndevs = ATOMIC_INIT(0);

Why?

> +static dev_t xsdfec_devt;

Why?

Why not use misc_device for this?  Why do you need your own major with a
bunch of minor devices reserved ahead of time?  Why not just create a
new misc device for every individual device that happens to be found in
the system?  That will make the code a lot simpler and smaller and
easier.



> +
> +/**
> + * struct xsdfec_dev - Driver data for SDFEC
> + * @regs: device physical base address
> + * @dev: pointer to device struct
> + * @config: Configuration of the SDFEC device
> + * @open_count: Count of char device being opened
> + * @xsdfec_cdev: Character device handle
> + * @irq_lock: Driver spinlock
> + *
> + * This structure contains necessary state for SDFEC driver to operate
> + */
> +struct xsdfec_dev {
> +	void __iomem *regs;
> +	struct device *dev;
> +	struct xsdfec_config config;
> +	atomic_t open_count;
> +	struct cdev xsdfec_cdev;
> +	/* Spinlock to protect state_updated and stats_updated */
> +	spinlock_t irq_lock;
> +};
> +
> +static const struct file_operations xsdfec_fops = {
> +	.owner = THIS_MODULE,
> +};

No operations at all?  That's an easy driver :)

thanks,

greg k-h