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