diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/clk/clk.c | 37 |
1 files changed, 33 insertions, 4 deletions
diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 8e728f395b54..efbc802da3b3 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -2000,6 +2000,7 @@ EXPORT_SYMBOL_GPL(clk_set_rate_exclusive); int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max) { int ret = 0; + unsigned long old_min, old_max, rate; if (!clk) return 0; @@ -2016,10 +2017,38 @@ int clk_set_rate_range(struct clk *clk, unsigned long min, unsigned long max) if (clk->exclusive_count) clk_core_rate_unprotect(clk->core); - if (min != clk->min_rate || max != clk->max_rate) { - clk->min_rate = min; - clk->max_rate = max; - ret = clk_core_set_rate_nolock(clk->core, clk->core->req_rate); + /* Save the current values in case we need to rollback the change */ + old_min = clk->min_rate; + old_max = clk->max_rate; + clk->min_rate = min; + clk->max_rate = max; + + rate = clk_core_get_rate_nolock(clk->core); + if (rate < min || rate > max) { + /* + * FIXME: + * We are in bit of trouble here, current rate is outside the + * the requested range. We are going try to request appropriate + * range boundary but there is a catch. It may fail for the + * usual reason (clock broken, clock protected, etc) but also + * because: + * - round_rate() was not favorable and fell on the wrong + * side of the boundary + * - the determine_rate() callback does not really check for + * this corner case when determining the rate + */ + + if (rate < min) + rate = min; + else + rate = max; + + ret = clk_core_set_rate_nolock(clk->core, rate); + if (ret) { + /* rollback the changes */ + clk->min_rate = old_min; + clk->max_rate = old_max; + } } if (clk->exclusive_count) |