When referencing clocks in DTS registered by another driver, clk_resolve_parent_clk() is supposed to return the name of the child device that provides the requested clock. However, in reality, it returns the name of the parent DTB node (e.g. clock-controller@1a240000). Such devices, for instance the exynos7870-cmu-peri driver, do not store any clock information in their dev->uclass_priv_ because they expect you to call dev->ops->get_rate with the appropriate clk->id. So when you try to resolve a clock that depends on an externally referenced clock, the resolution fails on the parent clock because it doesn't have a dev->uclass_priv_. With this change clk_resolve_parent_clk() will take an extra step to actually resolve the child device.
Signed-off-by: chiffathefox <[email protected]> --- drivers/clk/clk-uclass.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/clk/clk-uclass.c b/drivers/clk/clk-uclass.c index 0584429bed6..bea45fc396f 100644 --- a/drivers/clk/clk-uclass.c +++ b/drivers/clk/clk-uclass.c @@ -430,6 +430,7 @@ clk_resolve_parent_clk(struct udevice *dev, const char *name) { struct udevice *parent; struct clk clk; + struct clk *c; int ret; ret = uclass_get_device_by_name(UCLASS_CLK, name, &parent); @@ -440,7 +441,11 @@ clk_resolve_parent_clk(struct udevice *dev, const char *name) if (!clk.dev) return name; - return clk.dev->name; + ret = clk_get_by_id(clk.id, &c); + if (ret) + return name; + + return c->dev->name; } int clk_release_all(struct clk *clk, unsigned int count) -- 2.34.1
