netdev - [PATCH v8 13/17] PCI/pwrctl: reuse the OF node for power controlled devices

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Message-Id: <20240528-pwrseq-v8-13-d354d52b763c@linaro.org>
Date: Tue, 28 May 2024 21:03:21 +0200
From: Bartosz Golaszewski <brgl@...ev.pl>
To: Liam Girdwood <lgirdwood@...il.com>, Mark Brown <broonie@...nel.org>, 
 Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>, 
 Conor Dooley <conor+dt@...nel.org>, Marcel Holtmann <marcel@...tmann.org>, 
 Luiz Augusto von Dentz <luiz.dentz@...il.com>, 
 "David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, 
 Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, 
 Balakrishna Godavarthi <quic_bgodavar@...cinc.com>, 
 Rocky Liao <quic_rjliao@...cinc.com>, Kalle Valo <kvalo@...nel.org>, 
 Jeff Johnson <jjohnson@...nel.org>, Bjorn Andersson <andersson@...nel.org>, 
 Konrad Dybcio <konrad.dybcio@...aro.org>, 
 Bartosz Golaszewski <brgl@...ev.pl>, Bjorn Helgaas <bhelgaas@...gle.com>, 
 Srini Kandagatla <srinivas.kandagatla@...aro.org>, 
 Elliot Berman <quic_eberman@...cinc.com>, 
 Caleb Connolly <caleb.connolly@...aro.org>, 
 Neil Armstrong <neil.armstrong@...aro.org>, 
 Dmitry Baryshkov <dmitry.baryshkov@...aro.org>, 
 Alex Elder <elder@...nel.org>
Cc: linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org, 
 devicetree@...r.kernel.org, linux-bluetooth@...r.kernel.org, 
 netdev@...r.kernel.org, linux-wireless@...r.kernel.org, 
 ath11k@...ts.infradead.org, Jeff Johnson <quic_jjohnson@...cinc.com>, 
 ath12k@...ts.infradead.org, linux-pm@...r.kernel.org, 
 linux-pci@...r.kernel.org, 
 Bartosz Golaszewski <bartosz.golaszewski@...aro.org>, kernel@...cinc.com, 
 Amit Pundir <amit.pundir@...aro.org>
Subject: [PATCH v8 13/17] PCI/pwrctl: reuse the OF node for power
 controlled devices

From: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>

With PCI power control we deal with two struct device objects bound to
two different drivers but consuming the same OF node. We must not bind
the pinctrl twice. To that end: before setting the OF node of the newly
instantiated PCI device, check if a platform device consuming the same
OF node doesn't already exist on the platform bus and - if so - mark the
PCI device as reusing the OF node.

Tested-by: Amit Pundir <amit.pundir@...aro.org>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@...aro.org>
---
 drivers/pci/of.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/of.c b/drivers/pci/of.c
index 51e3dd0ea5ab..b908fe1ae951 100644
--- a/drivers/pci/of.c
+++ b/drivers/pci/of.c
@@ -6,6 +6,7 @@
  */
 #define pr_fmt(fmt)	"PCI: OF: " fmt

+#include <linux/cleanup.h>
 #include <linux/irqdomain.h>
 #include <linux/kernel.h>
 #include <linux/pci.h>
@@ -13,6 +14,7 @@
 #include <linux/of_irq.h>
 #include <linux/of_address.h>
 #include <linux/of_pci.h>
+#include <linux/platform_device.h>
 #include "pci.h"

 #ifdef CONFIG_PCI
@@ -25,16 +27,20 @@
  */
 int pci_set_of_node(struct pci_dev *dev)
 {
-	struct device_node *node;
-
 	if (!dev->bus->dev.of_node)
 		return 0;

-	node = of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
+	struct device_node *node __free(device_node) =
+		of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn);
 	if (!node)
 		return 0;

-	device_set_node(&dev->dev, of_fwnode_handle(node));
+	struct device *pdev __free(put_device) =
+		bus_find_device_by_of_node(&platform_bus_type, node);
+	if (pdev)
+		dev->bus->dev.of_node_reused = true;
+
+	device_set_node(&dev->dev, of_fwnode_handle(no_free_ptr(node)));
 	return 0;
 }

-- 
2.43.0