[RFC PATCH 3/6] bus: Add basic sc7180 bus driver

[Stephen Boyd <swboyd@chromium.org>]

Add a bus driver that does nothing besides populate devices as a child
of the soc device.

Cc: Rob Herring <robh@kernel.org>
Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Konrad Dybcio <konradybcio@kernel.org>
Cc: <linux-arm-msm@vger.kernel.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
---
 drivers/bus/Kconfig            |  3 ++
 drivers/bus/Makefile           |  3 ++
 drivers/bus/qcom/Kconfig       | 16 +++++++++++
 drivers/bus/qcom/Makefile      |  3 ++
 drivers/bus/qcom/qcom-sc7180.c | 51 ++++++++++++++++++++++++++++++++++
 5 files changed, 76 insertions(+)
 create mode 100644 drivers/bus/qcom/Kconfig
 create mode 100644 drivers/bus/qcom/Makefile
 create mode 100644 drivers/bus/qcom/qcom-sc7180.c

diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 7c2aa1350578..69963f0f02f3 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -284,6 +284,9 @@ config OF_SIMPLE_BUS
 	  symbol if ALLOW_SIMPLE_BUS_OVERRIDE is set and there isn't another
 	  driver for the simple-bus compatible.
 
+# SoC specific drivers
+source "drivers/bus/qcom/Kconfig"
+
 source "drivers/bus/fsl-mc/Kconfig"
 source "drivers/bus/mhi/Kconfig"
 
diff --git a/drivers/bus/Makefile b/drivers/bus/Makefile
index f3968221d704..796dd0515578 100644
--- a/drivers/bus/Makefile
+++ b/drivers/bus/Makefile
@@ -40,6 +40,9 @@ obj-$(CONFIG_VEXPRESS_CONFIG)	+= vexpress-config.o
 
 obj-$(CONFIG_DA8XX_MSTPRI)	+= da8xx-mstpri.o
 
+# SoC specific drivers
+obj-y				+= qcom/
+
 # Must be last for driver registration ordering
 obj-$(CONFIG_OF_SIMPLE_BUS)	+= simple-bus.o
 
diff --git a/drivers/bus/qcom/Kconfig b/drivers/bus/qcom/Kconfig
new file mode 100644
index 000000000000..f4c5d05ec9ca
--- /dev/null
+++ b/drivers/bus/qcom/Kconfig
@@ -0,0 +1,16 @@
+# SPDX-License-Identifier: GPL-2.0
+
+menuconfig QCOM_SOC_BUS
+	tristate "Qualcomm SoC Bus Drivers"
+	depends on ARCH_QCOM || COMPILE_TEST
+
+if QCOM_SOC_BUS
+
+config QCOM_SOC_BUS_SC7180
+	tristate "Qualcomm SC7180 SoC Bus"
+	depends on ALLOW_SIMPLE_BUS_OVERRIDE
+	depends on OF_SIMPLE_BUS || !OF_SIMPLE_BUS
+	help
+	  Support for the Qualcomm SC7180 SoC bus.
+
+endif
diff --git a/drivers/bus/qcom/Makefile b/drivers/bus/qcom/Makefile
new file mode 100644
index 000000000000..5d41ad61fead
--- /dev/null
+++ b/drivers/bus/qcom/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_QCOM_SOC_BUS_SC7180)		+= qcom-sc7180.o
diff --git a/drivers/bus/qcom/qcom-sc7180.c b/drivers/bus/qcom/qcom-sc7180.c
new file mode 100644
index 000000000000..a615cf5a2129
--- /dev/null
+++ b/drivers/bus/qcom/qcom-sc7180.c
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * SoC bus driver for Qualcomm SC7180 SoCs
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+
+static int qcom_soc_sc7180_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
+
+	return of_platform_populate(np, NULL, NULL, dev);
+}
+
+static const struct of_device_id qcom_soc_sc7180_match[] = {
+	{ .compatible = "qcom,soc-sc7180", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, qcom_soc_sc7180_match);
+
+static struct platform_driver qcom_soc_sc7180_driver = {
+	.probe = qcom_soc_sc7180_probe,
+	.driver = {
+		.name = "qcom-soc-sc7180",
+		.of_match_table = qcom_soc_sc7180_match,
+		.suppress_bind_attrs = true,
+	},
+};
+
+static int __init qcom_soc_sc7180_driver_init(void)
+{
+	return platform_driver_register(&qcom_soc_sc7180_driver);
+}
+/* Register before simple-bus driver. */
+arch_initcall(qcom_soc_sc7180_driver_init);
+
+static void __exit qcom_soc_sc7180_driver_exit(void)
+{
+	platform_driver_unregister(&qcom_soc_sc7180_driver);
+}
+module_exit(qcom_soc_sc7180_driver_exit);
+
+MODULE_DESCRIPTION("Qualcomm SC7180 SoC Driver");
+MODULE_LICENSE("GPL");
-- 
https://chromeos.dev