Commit Graph

3 Commits

Author SHA1 Message Date
Boris Brezillon dca1a4b5ff clk: at91: keep slow clk enabled to prevent system hang
All slow clk users are not properly claiming it (get + prepare + enable)
before using it.
If all users properly claiming this clock release it, the clock is
disabled, but faulty users still depends on it, and the system hangs.

This fix prevents the slow clock from being disabled, and should solve the
hanging issue, but offending drivers should be patched to properly claim
this clock.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reported-by: Bo Shen <voice.shen@atmel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Michael Turquette <mturquette@linaro.org>
2015-01-13 10:54:01 -08:00
Boris BREZILLON e8531ac8b2 clk: at91: fix num_parents test in at91sam9260 slow clk implementation
The slow clk block provided by at91sam9260 and derived SoCs should always
have 2 parents.

Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
2014-09-02 14:44:41 -07:00
Boris BREZILLON 80eded6ce8 clk: at91: add slow clks driver
AT91 slow clk is a clk multiplexer.

In some SoCs (sam9x5, sama5, sam9g45 families) this multiplexer can
choose among 2 sources: an internal RC oscillator circuit and an oscillator
using an external crystal.

In other Socs (sam9260 family) the multiplexer source is hardcoded with
the OSCSEL signal.

Signed-off-by: Boris BREZILLON <boris.brezillon@free-electrons.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
2014-05-07 18:27:45 +02:00