Re: [PATCH 12/19] i2c: mux: pca954x: make use of raw_spinlock variants

From: Peter Rosin
Date: Thu Mar 16 2017 - 15:54:09 EST


On 2017-03-09 17:21, Julia Cartwright wrote:
> The pca954x i2c mux driver currently implements an irq_chip for handling
> interrupts; due to how irq_chip handling is done, it's necessary for the
> irq_chip methods to be invoked from hardirq context, even on a a
> real-time kernel. Because the spinlock_t type becomes a "sleeping"
> spinlock w/ RT kernels, it is not suitable to be used with irq_chips.
>
> A quick audit of the operations under the lock reveal that they do only
> minimal, bounded work, and are therefore safe to do under a raw spinlock.
>
> Signed-off-by: Julia Cartwright <julia@xxxxxx>

Patch applied to the i2c-mux repo. Thanks!

Cheers,
peda