[PATCH v5 18/18] PCI/pwrctl: add a PCI power control driver for power sequenced devices

From: Bartosz Golaszewski <brgl@bgdev.pl>
To: Marcel Holtmann <marcel@holtmann.org>,
	Luiz Augusto von Dentz <luiz.dentz@gmail.com>,
	"David S . Miller" <davem@davemloft.net>,
	Eric Dumazet <edumazet@google.com>,
	Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>, Kalle Valo <kvalo@kernel.org>,
	Bjorn Andersson <andersson@kernel.org>,
	Konrad Dybcio <konrad.dybcio@linaro.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Bjorn Helgaas <bhelgaas@google.com>,
	Bartosz Golaszewski <brgl@bgdev.pl>,
	Saravana Kannan <saravanak@google.com>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Arnd Bergmann <arnd@arndb.de>,
	Neil Armstrong <neil.armstrong@linaro.org>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Alex Elder <elder@linaro.org>,
	Srini Kandagatla <srinivas.kandagatla@linaro.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Abel Vesa <abel.vesa@linaro.org>,
	Manivannan Sadhasivam <mani@kernel.org>,
	Lukas Wunner <lukas@wunner.de>,
	Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: linux-bluetooth@vger.kernel.org, netdev@vger.kernel.org,
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-wireless@vger.kernel.org, linux-arm-msm@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org,
	linux-pm@vger.kernel.org,
	Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Subject: [PATCH v5 18/18] PCI/pwrctl: add a PCI power control driver for power sequenced devices
Date: Fri, 16 Feb 2024 21:32:15 +0100	[thread overview]
Message-ID: <20240216203215.40870-19-brgl@bgdev.pl> (raw)
In-Reply-To: <20240216203215.40870-1-brgl@bgdev.pl>

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

Add a PCI power control driver that's capable of correctly powering up
devices using the power sequencing subsystem. The first user of this
driver is the ath11k module on QCA6390.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
 drivers/pci/pwrctl/Kconfig             |  9 +++
 drivers/pci/pwrctl/Makefile            |  1 +
 drivers/pci/pwrctl/pci-pwrctl-pwrseq.c | 84 ++++++++++++++++++++++++++
 3 files changed, 94 insertions(+)
 create mode 100644 drivers/pci/pwrctl/pci-pwrctl-pwrseq.c

diff --git a/drivers/pci/pwrctl/Kconfig b/drivers/pci/pwrctl/Kconfig
index b91170ebfb49..3880a88aa73b 100644
--- a/drivers/pci/pwrctl/Kconfig
+++ b/drivers/pci/pwrctl/Kconfig
@@ -5,6 +5,15 @@ menu "PCI Power control drivers"
 config PCI_PWRCTL
 	tristate
 
+config PCI_PWRCTL_PWRSEQ
+	tristate "PCI Power Control driver using the Power Sequencing subsystem"
+	select POWER_SEQUENCING
+	select PCI_PWRCTL
+	default m if (ATH11K_PCI && ARCH_QCOM)
+	help
+	  Enable support for the PCI power control driver for device
+	  drivers using the Power Sequencing subsystem.
+
 config PCI_PWRCTL_WCN7850
 	tristate "PCI Power Control driver for WCN7850"
 	select PCI_PWRCTL
diff --git a/drivers/pci/pwrctl/Makefile b/drivers/pci/pwrctl/Makefile
index de20c3af1b78..47ab9db1fb42 100644
--- a/drivers/pci/pwrctl/Makefile
+++ b/drivers/pci/pwrctl/Makefile
@@ -3,4 +3,5 @@
 obj-$(CONFIG_PCI_PWRCTL)		+= pci-pwrctl-core.o
 pci-pwrctl-core-y			:= core.o
 
+obj-$(CONFIG_PCI_PWRCTL_PWRSEQ)		+= pci-pwrctl-pwrseq.o
 obj-$(CONFIG_PCI_PWRCTL_WCN7850)	+= pci-pwrctl-wcn7850.o
diff --git a/drivers/pci/pwrctl/pci-pwrctl-pwrseq.c b/drivers/pci/pwrctl/pci-pwrctl-pwrseq.c
new file mode 100644
index 000000000000..43820a727b3f
--- /dev/null
+++ b/drivers/pci/pwrctl/pci-pwrctl-pwrseq.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2024 Linaro Ltd.
+ */
+
+#include <linux/device.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pci-pwrctl.h>
+#include <linux/platform_device.h>
+#include <linux/pwrseq/consumer.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+struct pci_pwrctl_pwrseq_data {
+	struct pci_pwrctl ctx;
+	struct pwrseq_desc *pwrseq;
+};
+
+static void devm_pci_pwrctl_pwrseq_power_off(void *data)
+{
+	struct pwrseq_desc *pwrseq = data;
+
+	pwrseq_power_off(pwrseq);
+}
+
+static int pci_pwrctl_pwrseq_probe(struct platform_device *pdev)
+{
+	struct pci_pwrctl_pwrseq_data *data;
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->pwrseq = devm_pwrseq_get(dev, of_device_get_match_data(dev));
+	if (IS_ERR(data->pwrseq))
+		return dev_err_probe(dev, PTR_ERR(data->pwrseq),
+				     "Failed to get the power sequencer\n");
+
+	ret = pwrseq_power_on(data->pwrseq);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "Failed to power-on the device\n");
+
+	ret = devm_add_action_or_reset(dev, devm_pci_pwrctl_pwrseq_power_off,
+				       data->pwrseq);
+	if (ret)
+		return ret;
+
+	data->ctx.dev = dev;
+
+	ret = devm_pci_pwrctl_device_set_ready(dev, &data->ctx);
+	if (ret)
+		return dev_err_probe(dev, ret,
+				     "Failed to register the pwrctl wrapper\n");
+
+	return 0;
+}
+
+static const struct of_device_id pci_pwrctl_pwrseq_of_match[] = {
+	{
+		/* ATH11K in QCA6390 package. */
+		.compatible = "pci17cb,1101",
+		.data = "wlan",
+	},
+	{ }
+};
+MODULE_DEVICE_TABLE(of, pci_pwrctl_pwrseq_of_match);
+
+static struct platform_driver pci_pwrctl_pwrseq_driver = {
+	.driver = {
+		.name = "pci-pwrctl-pwrseq",
+		.of_match_table = pci_pwrctl_pwrseq_of_match,
+	},
+	.probe = pci_pwrctl_pwrseq_probe,
+};
+module_platform_driver(pci_pwrctl_pwrseq_driver);
+
+MODULE_AUTHOR("Bartosz Golaszewski <bartosz.golaszewski@linaro.org>");
+MODULE_DESCRIPTION("Generic PCI Power Control module for power sequenced devices");
+MODULE_LICENSE("GPL");
-- 
2.40.1

