clk: bcm-2835: Remove rounding up the dividers
authorMaxime Ripard <maxime@cerno.tech>
Wed, 22 Sep 2021 12:54:16 +0000 (14:54 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 27 Jan 2022 09:53:45 +0000 (10:53 +0100)
commitb9c2343373f6bf19358db4e50197f5b3a17831db
tree940be42bc33411b68a78af6814eeffaedf93d89f
parent836dd37fe2bb0931e86fef788cdf44c3de4ff46d
clk: bcm-2835: Remove rounding up the dividers

[ Upstream commit 8ca011ef4af48a7af7b15afd8a4a44039dd04cea ]

The driver, once it found a divider, tries to round it up by increasing
the least significant bit of the fractional part by one when the
round_up argument is set and there's a remainder.

However, since it increases the divider it will actually reduce the
clock rate below what we were asking for, leading to issues with
clk_set_min_rate() that will complain that our rounded clock rate is
below the minimum of the rate.

Since the dividers are fairly precise already, let's remove that part so
that we can have clk_set_min_rate() working.

This is effectively a revert of 9c95b32ca093 ("clk: bcm2835: add a round
up ability to the clock divisor").

Fixes: 9c95b32ca093 ("clk: bcm2835: add a round up ability to the clock divisor")
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/20210922125419.4125779-3-maxime@cerno.tech
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/clk/bcm/clk-bcm2835.c