From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Dooks Subject: [PATCH] ASoC: rsnd: use fast_io for bus Date: Fri, 28 Mar 2014 11:20:59 +0000 Message-ID: <1396005659-14557-1-git-send-email-ben.dooks@codethink.co.uk> Return-path: Sender: linux-sh-owner@vger.kernel.org To: alsa-devel@alsa-project.org Cc: kuninori.morimoto.gx@renesas.com, broonie@kernel.org, lgirdwood@gmail.com, linux-sh@vger.kernel.org, magnus.damm@opensource.se, Ben Dooks List-Id: alsa-devel@alsa-project.org The rcar sound driver uses regmap to access registers in various parts of the block and uses regmap to manage mappings. The regmap is created without fast_io set, which means it locks with a mutex rather than a lighter-spinlock. The use of the mutex lock causes issues when the IRQ handler is entered as the code needs to read/write register values and thus with lock debugging enabled the system outputs a number of warnings such as: BUG: sleeping function called from invalid context at rnel/locking/mutex.c:616 The rcar registers are all connected via APB bus and thus not that slow to access. The fix is to set the fast_io in the code so that regmap creates the regmap structures using the faster spinlock functions. Signed-off-by: Ben Dooks --- sound/soc/sh/rcar/gen.c | 1 + 1 file changed, 1 insertion(+) diff --git a/sound/soc/sh/rcar/gen.c b/sound/soc/sh/rcar/gen.c index 9094970..6468962 100644 --- a/sound/soc/sh/rcar/gen.c +++ b/sound/soc/sh/rcar/gen.c @@ -66,6 +66,7 @@ static int rsnd_regmap_read32(void *context, } static struct regmap_bus rsnd_regmap_bus = { + .fast_io = true, .write = rsnd_regmap_write32, .read = rsnd_regmap_read32, .reg_format_endian_default = REGMAP_ENDIAN_NATIVE, -- 1.9.0