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    Subject[PATCH 4.14 034/186] clk: bcm-2835: Pick the closest clock rate
    Date
    From: Maxime Ripard <maxime@cerno.tech>

    [ Upstream commit 5517357a4733d7cf7c17fc79d0530cfa47add372 ]

    The driver currently tries to pick the closest rate that is lower than
    the rate being requested.

    This causes an issue with clk_set_min_rate() since it actively checks
    for the rounded rate to be above the minimum that was just set.

    Let's change the logic a bit to pick the closest rate to the requested
    rate, no matter if it's actually higher or lower.

    Fixes: 6d18b8adbe67 ("clk: bcm2835: Support for clock parent selection")
    Signed-off-by: Maxime Ripard <maxime@cerno.tech>
    Acked-by: Stephen Boyd <sboyd@kernel.org>
    Reviewed-by: Nicolas Saenz Julienne <nsaenz@kernel.org>
    Tested-by: Nicolas Saenz Julienne <nsaenz@kernel.org> # boot and basic functionality
    Tested-by: Michael Stapelberg <michael@stapelberg.ch>
    Link: https://patchwork.freedesktop.org/patch/msgid/20210922125419.4125779-2-maxime@cerno.tech
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    drivers/clk/bcm/clk-bcm2835.c | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    diff --git a/drivers/clk/bcm/clk-bcm2835.c b/drivers/clk/bcm/clk-bcm2835.c
    index 98295b9703178..d6cd1cc3f8e4d 100644
    --- a/drivers/clk/bcm/clk-bcm2835.c
    +++ b/drivers/clk/bcm/clk-bcm2835.c
    @@ -1233,7 +1233,7 @@ static int bcm2835_clock_determine_rate(struct clk_hw *hw,
    rate = bcm2835_clock_choose_div_and_prate(hw, i, req->rate,
    &div, &prate,
    &avgrate);
    - if (rate > best_rate && rate <= req->rate) {
    + if (abs(req->rate - rate) < abs(req->rate - best_rate)) {
    best_parent = parent;
    best_prate = prate;
    best_rate = rate;
    --
    2.34.1


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