Re: [PATCH] w1-gpio: Add GPIO w1 bus master driver

["Ville Syrjälä" <syrjala@sci.fi>]

On Fri, Dec 21, 2007 at 01:41:28PM +0300, Evgeniy Polyakov wrote:
> Hi Ville.
> 
> On Fri, Dec 21, 2007 at 09:34:01AM +0200, Ville Syrjala (syrjala@sci.fi) wrote:
> > Add a GPIO 1-wire bus master driver. The driver used the GPIO API to
> > control the wire and the GPIO pin can be specified using platform data
> > similar to i2c-gpio. The driver was tested with AT91SAM9260 + DS2401.
> 
> This looks ok, only a minor nit about codying style below.
> 
> > Signed-off-by: Ville Syrjala <syrjala@sci.fi>
> 
> ACK.
> 
> > +static int __init w1_gpio_probe(struct platform_device *pdev)
> > +{
> > +	struct w1_bus_master *master;
> > +	struct w1_gpio_platform_data *pdata;
> > +	int err;
> > +
> > +	pdata = pdev->dev.platform_data;
> > +	if (!pdata)
> > +		return -ENXIO;
> > +
> > +	master = kzalloc(sizeof *master, GFP_KERNEL);
> > +	if (!master)
> > +		return -ENOMEM;
> 
> I think sizeof(struct w1_bus_master) is a better way.

Will change.

> > new file mode 100644
> > index 0000000..3b80bb2
> > --- /dev/null
> > +++ b/include/linux/w1-gpio.h
> 
> Does anyone use this file except driver itself?

It's supposed to be used by the code that registers the platform device
(see the example in the documentation). No in-tree users since the board
I'm using is not supported by the kernel.

I just had a better look at i2c-gpio and noticed that I missed
gpio_request()/gpio_free() calls from the driver. Also the open-drain
requirement could be removed like i2c-gpio does. I'll send a new patch
ASAP.

-- 
Ville Syrjälä
syrjala@sci.fi
http://www.sci.fi/~syrjala/