UART clock is divided using divisor values from DLM/DLL registers when
enable-bit is unset in clk register and clk's divider configuration isn't
taken onto account in this case. This doesn't cause any problems, but
let's add a check for the divider's enable-bit state, for consistency.
Acked-by: Peter De Schrijver <pdeschrijver@xxxxxxxxxx>
Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
Changelog:
v2: In the comment to v1 Peter De Schrijver pointed out that UART's DLM/DLL
registers configuration is used when enable bit is unset, thus the
commit's title and message are changed accordingly.
drivers/clk/tegra/clk-divider.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/clk/tegra/clk-divider.c b/drivers/clk/tegra/clk-divider.c
index e76731fb7d69..f33c19045386 100644
--- a/drivers/clk/tegra/clk-divider.c
+++ b/drivers/clk/tegra/clk-divider.c
@@ -40,8 +40,13 @@ static unsigned long clk_frac_div_recalc_rate(struct clk_hw *hw,
int div, mul;
u64 rate = parent_rate;
- reg = readl_relaxed(divider->reg) >> divider->shift;
- div = reg & div_mask(divider);
+ reg = readl_relaxed(divider->reg);
+
+ if ((divider->flags & TEGRA_DIVIDER_UART) &&
+ !(reg & PERIPH_CLK_UART_DIV_ENB))
+ return rate;
+
+ div = (reg >> divider->shift) & div_mask(divider);
mul = get_mul(divider);
div += mul;
--
2.23.0
