On Tue, Aug 20, 2019 at 08:07:53AM -0500, Samuel Holland wrote:
> On 8/20/19 6:18 AM, Ondřej Jirman wrote:
> >> + reset = devm_reset_control_get(dev, NULL);
> >> + if (IS_ERR(reset)) {
> >> + ret = PTR_ERR(reset);
> >> + dev_err(dev, "Failed to get reset control: %d\n", ret);
> >> + goto err_disable_unprepare;
> >> + }
> >> +
> >> + ret = reset_control_deassert(reset);
> >> + if (ret) {
> >> + dev_err(dev, "Failed to deassert reset: %d\n", ret);
> >> + goto err_disable_unprepare;
> >> + }
> >
> > You need to assert the reset again from now on, in error paths. devm
> > will not do that for you.
>
> I know, and that's intentional. This same message box device is used for ATF
> to
> communicate with SCP firmware (on a different channel). This could be
> happening
> on a different core while Linux is running. So Linux is not allowed to
> deassert
> the reset. clk_disable_unprepare() is only okay because the clock is marked as
> critical.I agree with Ondrej that since this is clearly not the standard use of the API, this must have a big comment explaining why we're doing it this way. Maxime -- Maxime Ripard, Bootlin Embedded Linux and Kernel engineering https://bootlin.com -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/linux-sunxi/20190821123035.tl4aakijjhw3bwbk%40flea.
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