Re: [PATCHv2] i2c: omap: Disable default probing of i2c devices for omap i2c.

[Nishanth Menon <nm-l0cyMroinI0@public.gmane.org>]

On 04/09/2014 05:36 AM, Sourav Poddar wrote:
> I2c core supports defualt probing functionality for devices not registered through
> dt/board files. If there are any client driver registered, i2c core will try to
> check if there is any device present corresponding to the address supplied by
> the client driver. If the device is actually present and not registered, core
> will register it, else the device default probe will fail and we get a omap i2c controller
> specific timeout messages.
> For example, Using multi_v7_config on omap5-uevm, CONFIG_SENSORS_LM90 and CONFIG_ICS932S401
> is the driver which is enabled and gets registered. I2c core tries to find a valid
> corresponding device on each of the address supplied by registered driver,
> but could not find anyone. Hence, keep dumping the controller timeout speciic message.
> 
> The patch tends to disable class based instantiation, default probing will not be attempted
> by the i2c-core for omap i2c. Device will always get registered through device tree(dt case)
> and board files(for non dt cases).


Conflicts against commit 04eceb00e5f793013392ad8713c645a8132f648c
(i2c: i2c-omap: deprecate class based instantiation) in next-20140409

if you are dropping HWMON
adap->class = I2C_CLASS_HWMON | I2C_CLASS_DEPRECATED;
this might be a good time to explain why.

Also drop the following testing information down into diffstat
section, there is no need to retain that information in git history.

> 
> Tested i2c enumeration and data transfer(using i2c utilities) with linux-next master
> on the following boards using omap2plus_defconfig:
> * Omap3 beagle-Xm (for dt and non dt case)
> * omap4 panda
> * omap5-uevm
> * Dra7xx
> * Beaglebone white
> * Beaglebone black
> * am335x-evm
> * AM43xx epos evm
> 
> Tested i2c enumeration with linux-next master(except omap5)
> on the following boards using multi_v7_defconfig:
> * Omap3 beagle-Xm (for dt and non dt case)
> * omap4 panda
> * omap5-uevm (tested on next-20140131 tag, where i2c problem can be seen) 
> * Dra7xx
> * Beaglebone white
> * Beaglebone black
> * am335x-evm
> * AM43xx epos evm
> 
> Cc: Felipe Balbi <balbi-l0cyMroinI0@public.gmane.org>
> Cc: Nishanth Menon <nm-l0cyMroinI0@public.gmane.org>
> Signed-off-by: Sourav Poddar <sourav.poddar-l0cyMroinI0@public.gmane.org>
> Reported-by: Nishanth Menon <nm-l0cyMroinI0@public.gmane.org>
> ---

also indicate here against which tree and branch this patch is for.

> v1->v2:
>  add "Reported-by" attribute
>  drivers/i2c/busses/i2c-omap.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
> index 85f8eac..4ec29a0 100644
> --- a/drivers/i2c/busses/i2c-omap.c
> +++ b/drivers/i2c/busses/i2c-omap.c
> @@ -1238,7 +1238,7 @@ omap_i2c_probe(struct platform_device *pdev)
>  	adap = &dev->adapter;
>  	i2c_set_adapdata(adap, dev);
>  	adap->owner = THIS_MODULE;
> -	adap->class = I2C_CLASS_HWMON | I2C_CLASS_DEPRECATED;
> +	adap->class = 0;
adap->class = I2C_CLASS_DEPRECATED
>  	strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
>  	adap->algo = &omap_i2c_algo;
>  	adap->dev.parent = &pdev->dev;
> 


-- 
Regards,
Nishanth Menon