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 10:03:03 +0000 (11:03 +0100)
commit49b570f5d2e4c8ec6f83d2d92fa0a523a367db86
tree256692a0e55f07ed6c4f7db8ecd90d963b605350
parent2ff7b32f6b3efbf021c151c01208386e62618aac
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