| From aa1aee0ffe7103a65f11866408bff2470c07ceb9 Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Mon, 30 Dec 2019 10:29:35 -0800 |
| Subject: clk: Use parent node pointer during registration if necessary |
| |
| From: Stephen Boyd <sboyd@kernel.org> |
| |
| [ Upstream commit 9011f92622e5ef2d075f45e5fa818776d4feb8c0 ] |
| |
| 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> |
| Link: https://lkml.kernel.org/r/20191230190455.141339-1-sboyd@kernel.org |
| [sboyd@kernel.org: Fixup kernel-doc notation] |
| Reviewed-by: Niklas Cassel <nks@flawful.org> |
| Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org> |
| Tested-by: Bjorn Andersson <bjorn.andersson@linaro.org> |
| Signed-off-by: Sasha Levin <sashal@kernel.org> |
| --- |
| 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 b0344a1a03704..62d0fc486d3a2 100644 |
| --- a/drivers/clk/clk.c |
| +++ b/drivers/clk/clk.c |
| @@ -3718,6 +3718,28 @@ fail_out: |
| 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 |
| + * |
| + * Return: device node pointer of @dev, or the device node pointer of |
| + * @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 |
| @@ -3733,7 +3755,7 @@ fail_out: |
| */ |
| 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); |
| |
| @@ -3749,7 +3771,8 @@ 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); |
| |
| -- |
| 2.20.1 |
| |