lkml.org 
[lkml]   [2020]   [Jan]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] clk: Use parent node pointer during registration if necessary
On Mon 30 Dec 11:04 PST 2019, Stephen Boyd wrote:

> Sometimes clk drivers are attached to devices which are children of a
> parent device that is connected to a node in DT. This happens when
> devices are MFD-ish and the parent device driver mostly registers child
> devices to match against drivers placed in their respective subsystem
> directories like drivers/clk, drivers/regulator, etc. When the clk
> driver calls clk_register() with a device pointer, that struct device
> pointer won't have a device_node associated with it because it was
> created purely in software as a way to partition logic to a subsystem.
>
> This causes problems for the way we find parent clks for the clks
> registered by these child devices because we look at the registering
> device's device_node pointer to lookup 'clocks' and 'clock-names'
> properties. Let's use the parent device's device_node pointer if the
> registering device doesn't have a device_node but the parent does. This
> simplifies clk registration code by avoiding the need to assign some
> device_node to the device registering the clk.
>
> Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
> Reported-by: Niklas Cassel <niklas.cassel@linaro.org>
> Signed-off-by: Stephen Boyd <sboyd@kernel.org>
> ---
>
> I decided to introduce a new function instead of trying to jam it all
> in the one line where we assign np. This way the function gets the
> true 'np' as an argument all the time.
>

Looks better.

> drivers/clk/clk.c | 27 +++++++++++++++++++++++++--
> 1 file changed, 25 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
> index b68e200829f2..a743fffe8e46 100644
> --- a/drivers/clk/clk.c
> +++ b/drivers/clk/clk.c
> @@ -3719,6 +3719,28 @@ __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw)
> return ERR_PTR(ret);
> }
>
> +/**
> + * dev_or_parent_of_node - Get device node of @dev or @dev's parent

()

> + * @dev: Device to get device node of
> + *
> + * Returns: device node pointer of @dev, or the device node pointer of

Return: (no 's')


With that,

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Tested-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Regards,
Bjorn

> + * @dev->parent if dev doesn't have a device node, or NULL if neither
> + * @dev or @dev->parent have a device node.
> + */
> +static struct device_node *dev_or_parent_of_node(struct device *dev)
> +{
> + struct device_node *np;
> +
> + if (!dev)
> + return NULL;
> +
> + np = dev_of_node(dev);
> + if (!np)
> + np = dev_of_node(dev->parent);
> +
> + return np;
> +}
> +
> /**
> * clk_register - allocate a new clock, register it and return an opaque cookie
> * @dev: device that is registering this clock
> @@ -3734,7 +3756,7 @@ __clk_register(struct device *dev, struct device_node *np, struct clk_hw *hw)
> */
> struct clk *clk_register(struct device *dev, struct clk_hw *hw)
> {
> - return __clk_register(dev, dev_of_node(dev), hw);
> + return __clk_register(dev, dev_or_parent_of_node(dev), hw);
> }
> EXPORT_SYMBOL_GPL(clk_register);
>
> @@ -3750,7 +3772,8 @@ EXPORT_SYMBOL_GPL(clk_register);
> */
> int clk_hw_register(struct device *dev, struct clk_hw *hw)
> {
> - return PTR_ERR_OR_ZERO(__clk_register(dev, dev_of_node(dev), hw));
> + return PTR_ERR_OR_ZERO(__clk_register(dev, dev_or_parent_of_node(dev),
> + hw));
> }
> EXPORT_SYMBOL_GPL(clk_hw_register);
>
>
> base-commit: e42617b825f8073569da76dc4510bfa019b1c35a
> --
> Sent by a computer, using git, on the internet
>

\
 
 \ /
  Last update: 2020-01-03 08:40    [W:0.056 / U:0.036 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site