Re: [PATCH v2 1/2] eeprom: Add IDT 89HPESx EEPROM/CSR driver

[Serge Semin <fancer.lancer@gmail.com>]

On Tue, Nov 29, 2016 at 08:37:50PM +0100, Greg KH <gregkh@linuxfoundation.org> wrote:
> On Tue, Nov 29, 2016 at 01:38:20AM +0300, Serge Semin wrote:
> > +struct idt_89hpesx_dev {
> > +	u32 eesize;
> > +	bool eero;
> > +	u8 eeaddr;
> > +
> > +	u8 inieecmd;
> > +	u8 inicsrcmd;
> > +	u8 iniccode;
> > +
> > +	atomic_t csr;
> > +
> > +	int (*smb_write)(struct idt_89hpesx_dev *, const struct idt_smb_seq *);
> > +	int (*smb_read)(struct idt_89hpesx_dev *, struct idt_smb_seq *);
> > +	struct mutex smb_mtx;
> > +
> > +	struct i2c_client *client;
> > +
> > +	struct bin_attribute *ee_file;
> > +	struct dentry *csr_dir;
> > +	struct dentry *csr_file;
> > +};
> > +#define to_pdev_kobj(__kobj) \
> > +	dev_get_drvdata(container_of(__kobj, struct device, kobj))
> 
> Is it a struct device, or a kobject?  This is totally confusing to me.
> 
> And can't you just use kobj_to_dev()?
> 

I just didn't know about kobj_to_dev() inline function. Totally agree that
container_of() should be replaced with it.
What does look confusing to you? Do you mean the name "to_pdev_kobj" of the
macro?

> > +/*
> > + * eeprom_attribute - EEPROM sysfs-node attributes
> > + *
> > + * NOTE Size will be changed in compliance with OF node. EEPROM attribute will
> > + * be read-only as well if the corresponding flag is specified in OF node.
> > + */
> > +BIN_ATTR(eeprom, 0644, idt_sysfs_eeprom_read, idt_sysfs_eeprom_write,
> > +	 EEPROM_DEF_SIZE);
> 
> static?
> 
> And BIN_ATTR_RW()?
> 
> thanks,
> 
> greg k-h

Of course it should be static. Thanks for noticing that.
But I intentionally utilized BIN_ATTR() instead of BIN_ATTR_RW(), because
the last one implies to define the read/write methods with names
"_name##_read"/"_name##_write", which totally get out of naming within the
driver source code. To tell the truth macro BIN_ATTR_RW() isn't that
popular in the kernel. Neither is BIN_ATTR() macro, but it suites my driver
better than the another one.

Thanks,
-Sergey