Hi Javier, On 11.07.2014 03:45, Javier Martinez Canillas wrote: > On 07/10/2014 11:59 AM, amit daniel kachhap wrote: >> On Sat, Jul 5, 2014 at 1:54 AM, Javier Martinez Canillas >> <javier.marti...@collabora.co.uk> wrote:
[snip] >>> @@ -111,6 +223,13 @@ static struct max77686_platform_data >>> *max77686_i2c_parse_dt_pdata(struct device >>> return NULL; >>> >>> dev->platform_data = pd; >>> + >>> + /* Read default index and ignore errors, since default is 0 */ >>> + of_property_read_u32(np, "max77686,pmic-buck-default-dvs-idx", >>> + &pd->buck_default_idx); >> Any error checking code here. Say if pmic-buck-default-dvs-idx exceed 8? > > I'm not a DT expert but AFAIK the kernel should expect the data in a FDT to be > correct and should not validate it on runtime. There is work-in-progress to > add > a proper schema checking for DTS to the dtc so on build time it can be > validated > that a DTS is valid. > > AFAIU the only thing that the kernel should check is if a required property > does > not exist. I'd disagree on this. IMHO schema (if it progresses further, as unfortunately I can't find time to dedicate to it and looks like it's similar for other people that used to be involved) should be focused on structural checks, i.e. proper layout of nodes and properties, basic data types and so, to figure out common errors earlier than at boot-up time. On kernel side this should be treated in the same way as platform data. I agree that some existing drivers do little to validate incoming data, but I believe it is a good practice to validate things that the driver has no control over, especially when it's about a PMIC, when invalid data can have quite serious effects and detecting even some of them (e.g. value to big, which would overflow in target bit field) might prevent a failure. Best regards, Tomasz -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
