On 01/05/2018 11:09 AM, Jerome Brunet wrote:
When a divider clock has CLK_DIVIDER_READ_ONLY set, it means that the register shall be left un-touched, but it does not mean the clock should stop rate propagation if CLK_SET_RATE_PARENT is setThis is properly handled in qcom clk-regmap-divider but it was not in the generic divider Fixes: e6d5e7d90be9 ("clk-divider: Fix READ_ONLY when divider > 1") Signed-off-by: Jerome Brunet <[email protected]> --- drivers/clk/clk-divider.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c index b49942b9fe50..a851d3e04c7f 100644 --- a/drivers/clk/clk-divider.c +++ b/drivers/clk/clk-divider.c @@ -348,6 +348,7 @@ static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, unsigned long *prate) { struct clk_divider *divider = to_clk_divider(hw); + struct clk_hw *hw_parent = clk_hw_get_parent(hw);
Very minor suggestion: This could be moved inside the if block since it is only used there.
int bestdiv;/* if read only, just return current value */@@ -356,6 +357,15 @@ static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate, bestdiv &= div_mask(divider->width); bestdiv = _get_div(divider->table, bestdiv, divider->flags, divider->width); + + /* Even a read-only clock can propagate a rate change */ + if (clk_hw_get_flags(hw) & CLK_SET_RATE_PARENT) { + if (!hw_parent) + return -EINVAL; + + *prate = clk_hw_round_rate(hw_parent, rate * bestdiv); + } + return DIV_ROUND_UP_ULL((u64)*prate, bestdiv); }
Tested-by: David Lechner <[email protected]>
