On 04/03/2012 12:55 PM, Thierry Reding wrote: > * Stephen Warren wrote: >> On 04/02/2012 02:37 AM, Thierry Reding wrote: >>> * Stephen Warren wrote: >>>> On 03/28/2012 08:33 AM, Thierry Reding wrote: >>>>> Add auxdata to instantiate the PWFM controller from a device tree, >>>>> include the corresponding nodes in the dtsi files for Tegra 20 and >>>>> Tegra 30 and add binding documentation. >>>>> >>>>> Signed-off-by: Thierry Reding <[email protected]> >>>>> Acked-by: Stephen Warren <[email protected]> >>>> >>>>> diff --git a/drivers/pwm/pwm-tegra.c b/drivers/pwm/pwm-tegra.c >>>> ... >>>>> +#ifdef CONFIG_OF >>>>> +static struct of_device_id tegra_pwm_of_match[] = { >>>>> + { .compatible = "nvidia,tegra20-pwm" }, >>>>> + { .compatible = "nvidia,tegra30-pwm" }, >>>> >>>> Could you swap those two lines, so that tegra30-pwm matches first. It >>>> makes no difference at present, but might in the future if the driver >>>> actually has to differentiate the two SoCs. >>> >>> I thought the matching order was determined by the compatible property in >>> the >>> device tree, not the OF match table of the driver. >> >> At least logically, yes. However, of_match_device() appears to iterate >> over each match table entry, checking whether it matches any string in >> the compatible flag. Perhaps this could be considered a bug? > > It certainly is counter-intuitive. Maybe Grant or Rob can comment?
I think the rule should be the match list is most specific to least specific and/or mutually exclusive like compatible strings. Most examples with multiple entries in the kernel seem to fall into the mutually exclusive case. For this case, I think would just drop tegra30-pwm altogether and only add it to the driver when you need to distinguish between the 2. The dts should have both though for Tegra3. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-tegra" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
