Messages in this thread Patch in this message | | | From | Jernej Skrabec <> | Subject | [PATCH 1/4] clk: sunxi-ng: Fix fractional mode for N-M clocks | Date | Sun, 30 Jul 2017 18:41:47 +0200 |
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N-M factor clock driver is missing a call to ccu_frac_helper_enable() when fractional mode is used. Additionally, most SoCs require that M factor must be set to 0 when fractional mode is used.
Without this patch, clock keeps the old value and clk_set_rate() returns without error.
Fixes: 6174a1e24b0d ("clk: sunxi-ng: Add N-M-factor clock support") CC: Maxime Ripard <maxime.ripard@free-electrons.com> Signed-off-by: Jernej Skrabec <jernej.skrabec@siol.net> --- drivers/clk/sunxi-ng/ccu_nm.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/sunxi-ng/ccu_nm.c b/drivers/clk/sunxi-ng/ccu_nm.c index 5e5e90a4a50c..c6ba866b99d3 100644 --- a/drivers/clk/sunxi-ng/ccu_nm.c +++ b/drivers/clk/sunxi-ng/ccu_nm.c @@ -117,10 +117,22 @@ static int ccu_nm_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long flags; u32 reg; - if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) + if (ccu_frac_helper_has_rate(&nm->common, &nm->frac, rate)) { + spin_lock_irqsave(nm->common.lock, flags); + + /* most SoCs require M to be 0 if fractional mode is used */ + reg = readl(nm->common.base + nm->common.reg); + reg &= ~GENMASK(nm->m.width + nm->m.shift - 1, nm->m.shift); + writel(reg, nm->common.base + nm->common.reg); + + spin_unlock_irqrestore(nm->common.lock, flags); + + ccu_frac_helper_enable(&nm->common, &nm->frac); + return ccu_frac_helper_set_rate(&nm->common, &nm->frac, rate); - else + } else { ccu_frac_helper_disable(&nm->common, &nm->frac); + } _nm.min_n = nm->n.min ?: 1; _nm.max_n = nm->n.max ?: 1 << nm->n.width; -- 2.13.3
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