Re: [PATCH] ARM: dts: r8a7791: Don't disable referenced optional clocks

[Sergei Shtylyov]

On 04/06/2016 03:52 PM, Sjoerd Simons wrote:

clk_get on a disabled clock node will return EPROBE_DEFER, which can
cause drivers to be deferred forever if such clocks are referenced in
their clocks property.
Update the various disabled external clock nodes to default to a
frequency of 0, but don't disable them to prevent this.

Signed-off-by: Sjoerd Simons <sjoerd.sim...@collabora.co.uk>

---

  arch/arm/boot/dts/r8a7791-koelsch.dts | 1 +
  arch/arm/boot/dts/r8a7791-porter.dts  | 1 +
  arch/arm/boot/dts/r8a7791.dtsi        | 5 +----
  3 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/arm/boot/dts/r8a7791-koelsch.dts 
b/arch/arm/boot/dts/r8a7791-koelsch.dts
index 1adf877..da59c28 100644
--- a/arch/arm/boot/dts/r8a7791-koelsch.dts
+++ b/arch/arm/boot/dts/r8a7791-koelsch.dts
@@ -660,6 +660,7 @@
  };

  &pcie_bus_clk {
+       clock-frequency = <100000000>;

   Hmmm, looking at the Koelsch schematics, I don't see this clock. :-/

        status = "okay";
  };

diff --git a/arch/arm/boot/dts/r8a7791-porter.dts 
b/arch/arm/boot/dts/r8a7791-porter.dts
index 9554d13..19b257e 100644
--- a/arch/arm/boot/dts/r8a7791-porter.dts
+++ b/arch/arm/boot/dts/r8a7791-porter.dts
@@ -413,6 +413,7 @@
  };

  &pcie_bus_clk {
+       clock-frequency = <100000000>;
        status = "okay";
  };


   Again, looking at the Porter schematics, I don't see this clock either. :-/

diff --git a/arch/arm/boot/dts/r8a7791.dtsi b/arch/arm/boot/dts/r8a7791.dtsi
index 8693888..676df63 100644
--- a/arch/arm/boot/dts/r8a7791.dtsi
+++ b/arch/arm/boot/dts/r8a7791.dtsi
@@ -1104,8 +1104,7 @@
                pcie_bus_clk: pcie_bus {
                        compatible = "fixed-clock";
                        #clock-cells = <0>;
-                       clock-frequency = <100000000>;
-                       status = "disabled";
+                       clock-frequency = <0>;

   If the clock has a good default frequency, I don't think you need to 
remove it. Otherwise you missed USB_EXTAL which is 48 MHz (and can be overridden).

[...]

MBR, Sergei