[PATCH AUTOSEL 4.19 40/50] clk: qcom: gcc-sdm845: Use floor ops for sdcc clks

From: Sasha Levin
Date: Tue Sep 24 2019 - 12:50:20 EST


From: Stephen Boyd <swboyd@xxxxxxxxxxxx>

[ Upstream commit 5e4b7e82d497580bc430576c4c9bce157dd72512 ]

Some MMC cards fail to enumerate properly when inserted into an MMC slot
on sdm845 devices. This is because the clk ops for qcom clks round the
frequency up to the nearest rate instead of down to the nearest rate.
For example, the MMC driver requests a frequency of 52MHz from
clk_set_rate() but the qcom implementation for these clks rounds 52MHz
up to the next supported frequency of 100MHz. The MMC driver could be
modified to request clk rate ranges but for now we can fix this in the
clk driver by changing the rounding policy for this clk to be round down
instead of round up.

Fixes: 06391eddb60a ("clk: qcom: Add Global Clock controller (GCC) driver for SDM845")
Reported-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Cc: Taniya Das <tdas@xxxxxxxxxxxxxx>
Signed-off-by: Stephen Boyd <swboyd@xxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/20190830195142.103564-1-swboyd@xxxxxxxxxxxx
Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Signed-off-by: Stephen Boyd <sboyd@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/clk/qcom/gcc-sdm845.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/qcom/gcc-sdm845.c b/drivers/clk/qcom/gcc-sdm845.c
index 3bf11a6200942..ada3e4aeb38f9 100644
--- a/drivers/clk/qcom/gcc-sdm845.c
+++ b/drivers/clk/qcom/gcc-sdm845.c
@@ -647,7 +647,7 @@ static struct clk_rcg2 gcc_sdcc2_apps_clk_src = {
.name = "gcc_sdcc2_apps_clk_src",
.parent_names = gcc_parent_names_10,
.num_parents = 5,
- .ops = &clk_rcg2_ops,
+ .ops = &clk_rcg2_floor_ops,
},
};

@@ -671,7 +671,7 @@ static struct clk_rcg2 gcc_sdcc4_apps_clk_src = {
.name = "gcc_sdcc4_apps_clk_src",
.parent_names = gcc_parent_names_0,
.num_parents = 4,
- .ops = &clk_rcg2_ops,
+ .ops = &clk_rcg2_floor_ops,
},
};

--
2.20.1