summaryrefslogtreecommitdiff
path: root/drivers/clk/clk-fractional-divider.c
diff options
context:
space:
mode:
authorA.s. Dong <aisheng.dong@nxp.com>2018-11-14 13:01:39 +0000
committerStephen Boyd <sboyd@kernel.org>2018-12-03 11:31:24 -0800
commite983da27f70e8d29f4ae7262d52e4d07129498f3 (patch)
tree595b5d52cc4c85ac86e31c70d47a4f64b51c5944 /drivers/clk/clk-fractional-divider.c
parent404680794224334bcbea498d571c645e1838c879 (diff)
clk: fractional-divider: add CLK_FRAC_DIVIDER_ZERO_BASED flag support
Adding CLK_FRAC_DIVIDER_ZERO_BASED flag to indicate the numerator and denominator value in register are start from 0. This can be used to support frac dividers like below: Divider output clock = Divider input clock x [(frac +1) / (div +1)] where frac/div in register is: 000b - Divide by 1. 001b - Divide by 2. 010b - Divide by 3. Cc: Stephen Boyd <sboyd@codeaurora.org> Cc: Michael Turquette <mturquette@baylibre.com> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Diffstat (limited to 'drivers/clk/clk-fractional-divider.c')
-rw-r--r--drivers/clk/clk-fractional-divider.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/clk/clk-fractional-divider.c b/drivers/clk/clk-fractional-divider.c
index fdf625fb10fa..7ccde6bd8dd5 100644
--- a/drivers/clk/clk-fractional-divider.c
+++ b/drivers/clk/clk-fractional-divider.c
@@ -40,6 +40,11 @@ static unsigned long clk_fd_recalc_rate(struct clk_hw *hw,
m = (val & fd->mmask) >> fd->mshift;
n = (val & fd->nmask) >> fd->nshift;
+ if (fd->flags & CLK_FRAC_DIVIDER_ZERO_BASED) {
+ m++;
+ n++;
+ }
+
if (!n || !m)
return parent_rate;
@@ -103,6 +108,11 @@ static int clk_fd_set_rate(struct clk_hw *hw, unsigned long rate,
GENMASK(fd->mwidth - 1, 0), GENMASK(fd->nwidth - 1, 0),
&m, &n);
+ if (fd->flags & CLK_FRAC_DIVIDER_ZERO_BASED) {
+ m--;
+ n--;
+ }
+
if (fd->lock)
spin_lock_irqsave(fd->lock, flags);
else