This driver is used to control the power state of the devices attached to
the PCI slots. Currently, it controls the voltage rails of the PCI slots
defined in the devicetree node of the root port.
The voltage rails for PCI slots are documented in the DT-schema:
https://github.com/devicetree-org/dt-schema/blob/v2024.11/dtschema/schemas/pci/pci-bus-common.yaml#L153
Since this driver has to work with different kind of slots (PCIe
x1/x4/x8/x16, Mini PCIe, PCI, etc.), the driver is thus using the
of_regulator_bulk_get_all() API to obtain the voltage regulators defined
in the DT node, instead of hardcoding them.
As such, the DT node of the root port should define the relevant supply
properties corresponding to the voltage rails of the PCI slot.
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20250116-pci-pwrctrl-slot-v3-5-827473c8fbf4@linaro.org
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
(cherry picked from commit 75996c92f4de309f855471927e6489f5a354cfd4)
Bug: 380139395
Change-Id: I26b93ff6503d52f3b87034d4dba82674332b88ab
Signed-off-by: Brian Norris <briannorris@google.com>
Current way of creating pwrctrl devices requires iterating through the
child devicetree nodes of the PCI bridge in pci_pwrctrl_create_devices().
Even though it works, it creates confusion as there is no symmetry between
this and pci_pwrctrl_unregister() function that removes the pwrctrl
devices.
So to make these two functions symmetric, move the creation of pwrctrl
devices to pci_scan_device(). During the scan of each device in a slot,
the devicetree node (if exists) for the PCI device will be checked. If it
has the supplies populated, then the pwrctrl device will be created.
Since the PCI device scan happens so early, there would be no "struct
pci_dev" available for the device. So the host bridge is used as the
parent of all pwrctrl devices.
One nice side effect of this move is that, it is now possible to have
pwrctrl devices for PCI bridges as well (to control the supplies of PCI
slots).
Suggested-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20250116-pci-pwrctrl-slot-v3-1-827473c8fbf4@linaro.org
[kwilczynski: commit log]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
(cherry picked from commit 957f40d039a98d630146f74f94b3f60a40a449e4)
Bug: 380139395
Change-Id: I519c1165cd4ad506bbbf9f993a5a34cb7e6d194b
Signed-off-by: Brian Norris <briannorris@google.com>
Rename pwrctrl functions and structures from "pwrctl" to "pwrctrl" to match
the similar file renames.
Link: https://lore.kernel.org/r/20241115214428.2061153-3-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Acked-by: Krzysztof Wilczyński <kw@linux.com>
(cherry picked from commit 3f925cd6287401bbc9d568f56d796a69c8bd292a)
[Brian: some v6.13 merge conflicts w.r.t. pwrctl vs pwrctrl naming]
Bug: 380139395
Change-Id: I494fa1b52a582780ede5aaf7179bbbae27bcfd18
Signed-off-by: Brian Norris <briannorris@google.com>
To slightly reduce confusion between "pwrctl" (the power controller and
power sequencing framework) and "bwctrl" (the bandwidth controller),
rename "pwrctl" to "pwrctrl" so they use the same "ctrl" suffix.
Rename drivers/pci/pwrctl/ to drivers/pci/pwrctrl/, including the related
MAINTAINERS, include file (include/linux/pci-pwrctl.h), Makefile, and
Kconfig changes.
This is the minimal rename of files only. A subsequent commit will rename
functions and data structures.
Link: https://lore.kernel.org/r/20241115214428.2061153-2-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Krzysztof Wilczyński <kwilczynski@kernel.org>
Acked-by: Krzysztof Wilczyński <kw@linux.com>
(cherry picked from commit b88cbaaa6fa109c2eb455d8fe2a318de0d197ea2)
Bug: 380139395
Change-Id: Ic62bba7be5bf652b995dd42bba9893a97c94d2a1
Signed-off-by: Brian Norris <briannorris@google.com>
Brian Norris
Manivannan Sadhasivam
Bjorn Helgaas