Re: [PATCH] Add support for flag status register on Micron chips.

[Jingoo Han <jg1.han@samsung.com>]

On Wednesday, April 09, 2014 7:07 PM, Marek Vasut wrote:
> On Tuesday, April 08, 2014 at 06:12:50 PM, grmoore@altera.com wrote:
> > From: Graham Moore <grmoore@altera.com>
> >
> > Some new Micron flash chips require reading the flag
> > status register to determine when operations have completed.
> >
> > Furthermore, chips with multi-die stacks of the 65nm 256Mb QSPI also
> > require reading the status register before reading the flag status
> > register.
> >
> > This patch adds support for the flag status register in the n25q512a1 and
> > n25q00 Micron QSPI flash chips.
> 
> [...]
> 
> > +static int read_fsr(struct m25p *flash)
> > +{
> > +	ssize_t retval;
> > +	u8 code = OPCODE_RDFSR;
> > +	u8 val;
> > +
> > +	retval = spi_write_then_read(flash->spi, &code, 1, &val, 1);
> > +
> > +	if (retval < 0) {
> > +		dev_err(&flash->spi->dev, "error %d reading FSR\n",
> > +				(int) retval);
> 
> Is the type-cast really needed here? Why ?

The type-cast looks clumsy.
The type of 'retval' is retval; thus, '%zd' can be used,
instead of '%d', as below.

 +		dev_err(&flash->spi->dev, "error %zd reading FSR\n",
 +				retval);


> 
> > +		return retval;
> > +	}
> > +
> > +	return val;
> > +}
> > +/*
> >   * Read configuration register, returning its value in the
> >   * location. Return the configuration register value.
> >   * Returns negative if error occured.
> > @@ -233,7 +259,7 @@ static inline int set_4byte(struct m25p *flash, u32
> > jedec_id, int enable) * Service routine to read status register until
> > ready, or timeout occurs. * Returns non-zero if error.
> >   */
> > -static int wait_till_ready(struct m25p *flash)
> > +static int _wait_till_ready(struct m25p *flash)
> 
> Please avoid using function names that start with underscore .

+1

I agree with Marek Vasut's opinion.
If there is no reason, please don't use it.

Best regards,
Jingoo Han

> [...]
> 
> Thanks!
> 
> Best regards,
> Marek Vasut