Re: [RFC,PATCH 1/2] Add a common struct clk

From: Lothar Waßmann
Date: Fri Jun 11 2010 - 06:08:15 EST


> > > > Using a mutex in clk_enable()/clk_disable() is a bad idea, since that
> > > > makes it impossible to call those functions in interrupt context.
> IMHO if a device generates an irq its clock should already be on. This
> way you don't need to enable or disable a clock in irq context.
You may want to disable a clock in the IRQ handler. The VPU driver in
the Freescale BSP for i.MX51 does exactly this.
Anyway I don't see any reason for using a mutex here instead of
spin_lock_irq_save() as all other implementations do.

Lothar Waßmann

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