| Message ID | 1417452162-20046-1-git-send-email-p.zabel@pengutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Mon, Dec 01, 2014 at 05:42:42PM +0100, Philipp Zabel wrote: > Assigning a clock parent to a mux with the CLK_MUX_READ_ONLY flag causes an > error "clk: failed to reparent read_only_mux to already_set_parent: -38" > even if the hardware is already set to the correct parent clock. > > This patch avoids the error message by checking whether the correct parent > is already set before calling clk_set_parent. This allows to use the > assigned-clock-parents device tree binding for clock muxes that are not > allowed to be changed anymore at the time of_clk_set_defaults is called. > > Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> Philipp, The patch should be sent to Mike Turquette <mturquette@linaro.org>. The patch itself makes sense to me, so Acked-by: Shawn Guo <shawn.guo@linaro.org> Shawn > --- > drivers/clk/clk-conf.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/clk/clk-conf.c b/drivers/clk/clk-conf.c > index aad4796..ca8dc86 100644 > --- a/drivers/clk/clk-conf.c > +++ b/drivers/clk/clk-conf.c > @@ -62,7 +62,8 @@ static int __set_clk_parents(struct device_node *node, bool clk_supplier) > goto err; > } > > - rc = clk_set_parent(clk, pclk); > + if (pclk != __clk_get_parent(clk)) > + rc = clk_set_parent(clk, pclk); > if (rc < 0) > pr_err("clk: failed to reparent %s to %s: %d\n", > __clk_get_name(clk), __clk_get_name(pclk), rc); > -- > 2.1.3 >
Hello Philipp, On Mon, Dec 01, 2014 at 05:42:42PM +0100, Philipp Zabel wrote: > diff --git a/drivers/clk/clk-conf.c b/drivers/clk/clk-conf.c > index aad4796..ca8dc86 100644 > --- a/drivers/clk/clk-conf.c > +++ b/drivers/clk/clk-conf.c > @@ -62,7 +62,8 @@ static int __set_clk_parents(struct device_node *node, bool clk_supplier) > goto err; > } > > - rc = clk_set_parent(clk, pclk); > + if (pclk != __clk_get_parent(clk)) > + rc = clk_set_parent(clk, pclk); > if (rc < 0) > pr_err("clk: failed to reparent %s to %s: %d\n", > __clk_get_name(clk), __clk_get_name(pclk), rc); I'd move the check for rc < 0 into the body of the if you introduced. i.e.: if (pclk != __clk_get_parent(clk)) { rc = clk_set_parent(clk, pclk); if (rc < 0) ... } Semantically it doesn't make a difference because rc is zero when this code is reached, but it makes it a bit clearer. Best regards Uwe
diff --git a/drivers/clk/clk-conf.c b/drivers/clk/clk-conf.c index aad4796..ca8dc86 100644 --- a/drivers/clk/clk-conf.c +++ b/drivers/clk/clk-conf.c @@ -62,7 +62,8 @@ static int __set_clk_parents(struct device_node *node, bool clk_supplier) goto err; } - rc = clk_set_parent(clk, pclk); + if (pclk != __clk_get_parent(clk)) + rc = clk_set_parent(clk, pclk); if (rc < 0) pr_err("clk: failed to reparent %s to %s: %d\n", __clk_get_name(clk), __clk_get_name(pclk), rc);
Assigning a clock parent to a mux with the CLK_MUX_READ_ONLY flag causes an error "clk: failed to reparent read_only_mux to already_set_parent: -38" even if the hardware is already set to the correct parent clock. This patch avoids the error message by checking whether the correct parent is already set before calling clk_set_parent. This allows to use the assigned-clock-parents device tree binding for clock muxes that are not allowed to be changed anymore at the time of_clk_set_defaults is called. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de> --- drivers/clk/clk-conf.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)