Re: [PATCH] ARM: davinci: register the usb20_phy clock on the DT file

From: David Lechner
Date: Wed Oct 26 2016 - 16:01:45 EST


On 10/26/2016 02:49 PM, ahaslam@xxxxxxxxxxxx wrote:
From: Axel Haslam <ahaslam@xxxxxxxxxxxx>

The usb20_phy clock needs to be registered for the driver to be able
to get and enable a clock. Currently the usb phy clocks are registered
form board files, which will not be called during a device tree based
boot.

To be able to probe correctly usb form a device tree boot, register
the usb phy clocks form the DT specific init.

Unfourtunatly, davinci does not have proper clock support on device tree
yet, so by registering the clock form de DT specific file we are
forced to hardcode the parent clock, and cannot select refclkin as
parent for any of the phy clocks of the da850 family.

As none of the current da850 based boards currently in mainline use
refclkin as source. I guess we can live with this limitation until clocks
are correctly represented through CCF/device tree.

Signed-off-by: Axel Haslam <ahaslam@xxxxxxxxxxxx>
---

This patch depends on David's series for usb clocks:

currently:
[PATCH v6 0/5] da8xx USB PHY platform devices and clocks
https://lkml.org/lkml/2016/10/25/867

arch/arm/mach-davinci/da8xx-dt.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/arm/mach-davinci/da8xx-dt.c b/arch/arm/mach-davinci/da8xx-dt.c
index c9f7e92..7947267 100644
--- a/arch/arm/mach-davinci/da8xx-dt.c
+++ b/arch/arm/mach-davinci/da8xx-dt.c
@@ -45,6 +45,8 @@

static void __init da850_init_machine(void)
{
+ da8xx_register_usb20_phy_clk(false);
+ da8xx_register_usb11_phy_clk(false);
of_platform_default_populate(NULL, da850_auxdata_lookup, NULL);
}




You should check for error on return and print a warning if there is an error. Like this: https://patchwork.kernel.org/patch/9395635/

(I actually just had to make this change a few minutes ago to troubleshoot a problem that I am working on. da8xx_register_usb11_phy_clk() is failing for some reason that I have not figured out yet.)