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author | Soren Brinkmann <soren.brinkmann@xilinx.com> | 2013-04-03 12:17:12 -0700 |
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committer | Mike Turquette <mturquette@linaro.org> | 2013-04-10 16:33:53 -0700 |
commit | fb72a0590b770f7da6a02bde6b8a147a3d9f6168 (patch) | |
tree | b842b02beb3a44b0d595f0b6020b8ed71c8f448e /include/linux/clk.h | |
parent | 312f0f0b9a4e3e2cc8ad1bbc4577a6dff025cdf6 (diff) | |
download | linux-stable-fb72a0590b770f7da6a02bde6b8a147a3d9f6168.tar.gz linux-stable-fb72a0590b770f7da6a02bde6b8a147a3d9f6168.tar.bz2 linux-stable-fb72a0590b770f7da6a02bde6b8a147a3d9f6168.zip |
clk: Properly handle notifier return values
Notifiers may return NOTIFY_(OK|DONE|STOP|BAD). The CCF uses an
inconsistent mix of checking against NOTIFY_STOP or NOTIFY_BAD.
This inconsistency leaves errors undetected in some cases:
clk_set_parent() calls __clk_speculate_rates(), which stops when it
hits a NOTIFIER_BAD (STOP is ignored), and passes this value back to the
caller.
clk_set_parent() compares this return value against NOTIFY_STOP only,
ignoring NOTIFY_BAD returns.
Use NOTIFY_STOP_MASK to detect a negative notifier return value and
document all four return value options.
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Diffstat (limited to 'include/linux/clk.h')
-rw-r--r-- | include/linux/clk.h | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/include/linux/clk.h b/include/linux/clk.h index b3ac22d0fc1f..9a6d04524b1a 100644 --- a/include/linux/clk.h +++ b/include/linux/clk.h @@ -28,16 +28,16 @@ struct clk; * PRE_RATE_CHANGE - called immediately before the clk rate is changed, * to indicate that the rate change will proceed. Drivers must * immediately terminate any operations that will be affected by the - * rate change. Callbacks may either return NOTIFY_DONE or - * NOTIFY_STOP. + * rate change. Callbacks may either return NOTIFY_DONE, NOTIFY_OK, + * NOTIFY_STOP or NOTIFY_BAD. * * ABORT_RATE_CHANGE: called if the rate change failed for some reason * after PRE_RATE_CHANGE. In this case, all registered notifiers on * the clk will be called with ABORT_RATE_CHANGE. Callbacks must - * always return NOTIFY_DONE. + * always return NOTIFY_DONE or NOTIFY_OK. * * POST_RATE_CHANGE - called after the clk rate change has successfully - * completed. Callbacks must always return NOTIFY_DONE. + * completed. Callbacks must always return NOTIFY_DONE or NOTIFY_OK. * */ #define PRE_RATE_CHANGE BIT(0) |