On Friday 21 March 2014 20:17:39 Maxime Ripard wrote: > On Fri, Mar 21, 2014 at 11:49:59AM -0400, Paul Gortmaker wrote: > > On Mon, Mar 10, 2014 at 7:29 AM, Russell King - ARM Linux > > <linux@xxxxxxxxxxxxxxxx> wrote: > > > On Mon, Mar 10, 2014 at 11:58:08AM +0100, Maxime Ripard wrote: > > >> On Fri, Mar 07, 2014 at 04:08:36PM +0000, Russell King - ARM Linux wrote: > > >> > On Fri, Mar 07, 2014 at 03:59:30PM +0100, Maxime Ripard wrote: > > >> > > @@ -900,7 +902,8 @@ mv64xxx_i2c_probe(struct platform_device *pd) > > >> > > exit_free_irq: > > >> > > free_irq(drv_data->irq, drv_data); > > >> > > exit_reset: > > >> > > - if (pd->dev.of_node && !IS_ERR(drv_data->rstc)) > > >> > > + if (pd->dev.of_node && IS_ENABLED(CONFIG_RESET_CONTROLLER) && > > >> > > + !IS_ERR(drv_data->rstc)) > > >> > > reset_control_assert(drv_data->rstc); > > >> > > > >> > Another question is... why do we need to check pd->dev.of_node here? > > >> > If CONFIG_RESET_CONTROLLER is set, we always try to get the reset > > >> > controller node, so drv_data->rstc is either going to be a valid > > >> > pointer, or it's going to be an error pointer - neither > > >> > reset_control_get() nor devm_reset_control_get return NULL. > > >> > > >> Following back on this as I was doing the patch, actually, > > >> drv_data->rstc will be NULL if we're not probed by DT, and hence never > > >> call reset_control_get, that would set an error pointer. > > >> > > >> But then, we can use IS_ERR_OR_NULL on drv_data->rstc. > > > > > > I think you can also move the devm_reset_control_get() into the main > > > probe function: you're only checking for -EPROBE_DEFER from it to fail, > > > allowing other errors to continue with the driver init. This means > > > that on non-OF, devm_reset_control_get() will fail with -ENOENT. > > > > Looping linux-next into the CC since this is the cause of the failure > > in orion5x_defconfig there, and no point in anyone else re-doing the > > same bisect. > > I sent a fix for this that hasn't been picked up yet: > http://lists.infradead.org/pipermail/linux-arm-kernel/2014-March/239069.html > > IIRC, Wolfram's away until Monday, so I guess it will be merged some > time next week. I think there is something wrong with an interface that makes you use IS_ERR_OR_NULL(). If you are calling reset_control_get_optional(), that' should not return an error when there is no reset controller listed in the device tree. We should still have a way to propagate -EPROBE_DEFER, or bail out if there is a reset controller but there is something wrong with it, but otherwise I'd suggest just leaving NULL as a valid pointer in drv_data->rstc and making sure that the reset controller functions can just deal with a NULL argument, so you never have to check it again. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
