If external source for the CLKS signal selection kept after the port is no longer in use the system might refuse to go suspend. There is also a chance that the external clock is not running when next time the McBSP port is started which can result errors when we try to access McBSP registers. Reset the CLKS source back to PRCM source unconditionally.
Signed-off-by: Peter Ujfalusi peter.ujfalusi@ti.com --- sound/soc/omap/mcbsp.c | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/sound/soc/omap/mcbsp.c b/sound/soc/omap/mcbsp.c index d716793..21dbb05 100644 --- a/sound/soc/omap/mcbsp.c +++ b/sound/soc/omap/mcbsp.c @@ -548,6 +548,16 @@ void omap_mcbsp_free(struct omap_mcbsp *mcbsp)
reg_cache = mcbsp->reg_cache;
+ /* + * Select CLKS source from internal source unconditionally before + * marking the McBSP port as free. + * If the external clock source via MCBSP_CLKS pin has been selected the + * system will refuse to enter idle if the CLKS pin source is not reset + * back to internal source. + */ + if (!cpu_class_is_omap1()) + omap2_mcbsp_set_clks_src(mcbsp, MCBSP_CLKS_PRCM_SRC); + spin_lock(&mcbsp->lock); if (mcbsp->free) dev_err(mcbsp->dev, "McBSP%d was not reserved\n", mcbsp->id);