Re: [PATCH 3/3] iio: potentiometer: mcp4531: Add device tree binding

[Florian Vaussard <florian.vaussard@heig-vd.ch>]

Hello Peter,

Le 21. 06. 16 à 09:51, Peter Rosin a écrit :
> On 2016-06-21 08:55, Florian Vaussard wrote:
>> This patch adds the necessary device tree binding to allow DT probing of
>> currently supported parts.
>>
>> Signed-off-by: Florian Vaussard <florian.vaussard@heig-vd.ch>
>> ---
>>  drivers/iio/potentiometer/mcp4531.c | 83 ++++++++++++++++++++++++++++++++++++-
>>  1 file changed, 82 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/iio/potentiometer/mcp4531.c b/drivers/iio/potentiometer/mcp4531.c
>> index 2251173..41a1e46 100644
>> --- a/drivers/iio/potentiometer/mcp4531.c
>> +++ b/drivers/iio/potentiometer/mcp4531.c
>> @@ -31,6 +31,8 @@
>>  #include <linux/module.h>
>>  #include <linux/i2c.h>
>>  #include <linux/err.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>>  
>>  #include <linux/iio/iio.h>
>>  
>> @@ -188,12 +190,84 @@ static const struct iio_info mcp4531_info = {
>>  	.driver_module = THIS_MODULE,
>>  };
>>  
>> +#ifdef CONFIG_OF
>> +static const struct of_device_id mcp45xx_of_match[] = {
> 
> Should be named mcp4531_of_match, also the casting to void and
> then back to an integer type is ugly. Would it work to store a
> pointer directly into the mcp4531_cfg array instead? I.e.
> 
> 	{ .compatible = "microchip,mcp4531-502", .data = &mcp4531_cfg[MCP453x_502] },
> etc
> 
> and then adjust accordingly in mcp4531_probe()?
> 

Yes the casting is pretty ugly. And kbuild agrees with you :) I took this from
another driver (lame excuse). Your suggestion is sensible, I will give it a try.

> That is, if you need this patch at all, see my reply to 2/3...
> 

This seems necessary in order to have the vendor ID in the compatible string.

Thanks for your review.

Florian