On 07/04/16 06:33, Marek Szyprowski wrote: > Hello, > > On 2016-04-06 22:33, Alison Schofield wrote: >> On Wed, Apr 06, 2016 at 09:03:00AM +0200, Marek Szyprowski wrote: >>> Hello, >>> >>> On 2016-04-06 07:15, Alison Schofield wrote: >>>> Driver includes struct regmap and struct device in its global data. >>>> Remove the struct device and use regmap API to retrieve device info. >>>> >>>> Patch created using Coccinelle plus manual edits. >>>> >>>> Signed-off-by: Alison Schofield <amsfield22@xxxxxxxxx> >>> This patch changes the struct device which is used by the driver to report >>> errors. The driver used correctly the struct device associated with its >>> device tree node, while after the patch it will use device which is >>> associated with PMU regmap, which is a different device. PMU regmap is there >>> only to enable/disable the ADC block and it is not the regmap used to access >>> registers of the ADC device. >>> >>> I would prefer to drop this patch. >> Thanks Marek! Please check my understanding. Driver is not carrying >> a duplicate struct device. The regmap in exynos_adc is *not* this >> devices regmap. It belongs to the PMU, (power mgmt unit?) > > Exactly. > >> It seemed excessive to carry around a struct device just for the >> dev_err messages, but, we need that struct to extract the correct >> iio_dev struct. Without a regmap belonging to this actual device, >> no efficiencies can be gained in exynos, and the patch will be >> dropped from set v2. > > Thanks. > >> Now I need to be able to recognize such cases elsewhere. I'm going >> back though other patches in this set looking for that, but I'm not >> so sure I would recognize it. >> >> Jonathan & all, Any hints on the rule of regmap? > > You may check how the regmap is initialized. When it is retrieved by > phandle from device tree, then you might be almost sure that it refers > to the different device. True enough. Most simple devices that stand alone should be fine for this sort of cleanup as the regmap is typically initiated directly for them. Jonathan > > Best regards -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
