Re: Problem with nbcon console and amba-pl011 serial port

["Russell King (Oracle)" <linux@armlinux.org.uk>]

On Wed, Jun 04, 2025 at 09:50:03AM +0206, John Ogness wrote:
> You are correct. I wasn't aware that the clock framework had a usage
> counter to allow recursive calls. Sorry for the noise.

It's documented:

/**
 * clk_disable - inform the system when the clock source is no longer required.
 * @clk: clock source
 *
 * Inform the system that a clock source is no longer required by
 * a driver and may be shut down.
 *
 * May be called from atomic contexts.
 *
 * Implementation detail: if the clock source is shared between
 * multiple drivers, clk_enable() calls must be balanced by the
 * same number of clk_disable() calls for the clock source to be
 * disabled.
 */

similarly for clk_unprepare(). It has to be this way if you think about
the fact that clock sources are not unique to clock consumers, otherwise
the first clock consumer to disable a clock will disrupt other
consumers of that same clock.

It's been that way since I created the clk API, which predates CCF.

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