On Thu, Jul 30, 2015 at 2:59 PM, Chunyan Zhang <zhang.lyra@xxxxxxxxx> wrote: > On Thu, Jul 30, 2015 at 2:37 PM, Alexander Shishkin > <alexander.shishkin@xxxxxxxxxxxxxxx> wrote: >> Chunyan Zhang <zhang.lyra@xxxxxxxxx> writes: >> >>> Sure, I mean, the root reason of this problem is here ( i.e. >>> "stm_core_up" was zero then): >>> if (!stm_core_up) >>> return -EPROBE_DEFER; >>> >>> Why it was zero? >>> Because the function (i.e. stm_core_init() ) in which "stm_core_up" >>> would be added one hasn't been executed at this moment. It would be >>> executed on module_init stage for you this version of patch. >> >> Again, this is the indented behavior. >> >>> The reason of this warning is: >>> After stm_probe() failed, clk_core_disable() would be called from >>> amba_put_disable_pclk(), then WARN_ON() happened: >>> if (WARN_ON(core->enable_count == 0)) >>> return; >>> >>> I'm guessing the reason why "core->enable_count" was 0 at this moment is: >>> I don't know who created a thread to process the >>> amba_pm_runtime_suspend(), in which clk_core_disable() was already >>> called, "core->enable_count" was, of course, cleared to zero then. >>> And this thread run before amba_put_disable_pclk(pcdev) which is just >>> the one called from amba_probe() after >>> "->probe"(i.e. stm_probe in this case) returning a non-zero value. >> >> No, this is guesswork. In amba_probe(), clocks are enabled for the >> drv->probe() and then disabled afterwards and that's where the refcount >> ends up unbalanced, the probe is the culprit. >> >> I can debug your driver for you but you'll at least need to put the code >> up somewhere so I can see it. > > The code has already been submitted like I said in the earlier emails, > you may refer [1]. > > Thanks, > Chunyan > > [1] https://lkml.org/lkml/2015/2/4/729 Er, sorry, it's too old, I'll send out an updated version soon. Thanks for your patience, Chunyan > >> >> Regards, >> -- >> Alex >> -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
