@@ -32,3 +32,14 @@ config AMD_WBRF
This mechanism will only be activated on platforms that advertise a
need for it.
+
+config AMD_ISP_PLATFORM
+ tristate "AMD ISP4 platform driver"
+ depends on I2C && X86_64 && ACPI && AMD_ISP4
+ help
+ Platform driver for AMD platforms containing image signal processor
+ gen 4. Provides camera sensor module board information to allow
+ sensor and V4L drivers to work properly.
+
+ This driver can also be built as a module. If so, the module
+ will be called amd_isp4.
@@ -10,3 +10,4 @@ obj-$(CONFIG_AMD_PMC) += pmc/
obj-$(CONFIG_AMD_HSMP) += hsmp/
obj-$(CONFIG_AMD_PMF) += pmf/
obj-$(CONFIG_AMD_WBRF) += wbrf.o
+obj-$(CONFIG_AMD_ISP_PLATFORM) += amd_isp4.o
new file mode 100644
@@ -0,0 +1,295 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * AMD ISP platform driver for sensor i2-client instantiation
+ *
+ * Copyright 2025 Advanced Micro Devices, Inc.
+ */
+
+#include <linux/acpi.h>
+#include <linux/device/bus.h>
+#include <linux/dmi.h>
+#include <linux/gpio/machine.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/units.h>
+
+#define AMDISP_OV05C10_I2C_ADDR 0x10
+#define AMDISP_OV05C10_PLAT_NAME "amdisp_ov05c10_platform"
+#define AMDISP_OV05C10_HID "OMNI5C10"
+#define AMDISP_OV05C10_REMOTE_EP_NAME "ov05c10_isp_4_1_1"
+#define AMD_ISP_PLAT_DRV_NAME "amd-isp4"
+
+/*
+ * AMD ISP platform definition to configure the device properties
+ * missing in the ACPI table.
+ */
+struct amdisp_platform {
+ const char *name;
+ u8 i2c_addr;
+ u8 max_num_swnodes;
+ struct i2c_board_info board_info;
+ struct notifier_block i2c_nb;
+ struct i2c_client *i2c_dev;
+ struct software_node **swnodes;
+};
+
+/* Top-level OV05C10 camera node property table */
+static const struct property_entry ov05c10_camera_props[] = {
+ PROPERTY_ENTRY_U32("clock-frequency", 24 * HZ_PER_MHZ),
+ { }
+};
+
+/* Root AMD ISP OV05C10 camera node definition */
+static const struct software_node camera_node = {
+ .name = AMDISP_OV05C10_HID,
+ .properties = ov05c10_camera_props,
+};
+
+/*
+ * AMD ISP OV05C10 Ports node definition. No properties defined for
+ * ports node for OV05C10.
+ */
+static const struct software_node ports = {
+ .name = "ports",
+ .parent = &camera_node,
+};
+
+/*
+ * AMD ISP OV05C10 Port node definition. No properties defined for
+ * port node for OV05C10.
+ */
+static const struct software_node port_node = {
+ .name = "port@",
+ .parent = &ports,
+};
+
+/*
+ * Remote endpoint AMD ISP node definition. No properties defined for
+ * remote endpoint node for OV05C10.
+ */
+static const struct software_node remote_ep_isp_node = {
+ .name = AMDISP_OV05C10_REMOTE_EP_NAME,
+};
+
+/*
+ * Remote endpoint reference for isp node included in the
+ * OV05C10 endpoint.
+ */
+static const struct software_node_ref_args ov05c10_refs[] = {
+ SOFTWARE_NODE_REFERENCE(&remote_ep_isp_node),
+};
+
+/* OV05C supports one single link frequency */
+static const u64 ov05c10_link_freqs[] = {
+ 925 * HZ_PER_MHZ,
+};
+
+/* OV05C supports only 2-lane configuration */
+static const u32 ov05c10_data_lanes[] = {
+ 1,
+ 2,
+};
+
+/* OV05C10 endpoint node properties table */
+static const struct property_entry ov05c10_endpoint_props[] = {
+ PROPERTY_ENTRY_U32("bus-type", 4),
+ PROPERTY_ENTRY_U32_ARRAY_LEN("data-lanes", ov05c10_data_lanes,
+ ARRAY_SIZE(ov05c10_data_lanes)),
+ PROPERTY_ENTRY_U64_ARRAY_LEN("link-frequencies", ov05c10_link_freqs,
+ ARRAY_SIZE(ov05c10_link_freqs)),
+ PROPERTY_ENTRY_REF_ARRAY("remote-endpoint", ov05c10_refs),
+ { }
+};
+
+/* AMD ISP endpoint node definition */
+static const struct software_node endpoint_node = {
+ .name = "endpoint",
+ .parent = &port_node,
+ .properties = ov05c10_endpoint_props,
+};
+
+/*
+ * AMD ISP swnode graph uses 5 nodes and also its relationship is
+ * fixed to align with the structure that v4l2 expects for successful
+ * endpoint fwnode parsing.
+ *
+ * It is only the node property_entries that will vary for each platform
+ * supporting different sensor modules.
+ */
+#define NUM_SW_NODES 5
+
+static const struct software_node *ov05c10_nodes[NUM_SW_NODES + 1] = {
+ &camera_node,
+ &ports,
+ &port_node,
+ &endpoint_node,
+ &remote_ep_isp_node,
+ NULL
+};
+
+/* OV05C10 specific AMD ISP platform configuration */
+static const struct amdisp_platform amdisp_ov05c10_platform_config = {
+ .name = AMDISP_OV05C10_PLAT_NAME,
+ .board_info = {
+ .dev_name = "ov05c10",
+ I2C_BOARD_INFO("ov05c10", AMDISP_OV05C10_I2C_ADDR),
+ },
+ .i2c_addr = AMDISP_OV05C10_I2C_ADDR,
+ .max_num_swnodes = NUM_SW_NODES,
+ .swnodes = (struct software_node **)ov05c10_nodes,
+};
+
+static const struct acpi_device_id amdisp_sensor_ids[] = {
+ { AMDISP_OV05C10_HID },
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, amdisp_sensor_ids);
+
+static bool is_isp_i2c_adapter(struct i2c_adapter *adap)
+{
+ return !strcmp(adap->owner->name, "i2c_designware_amdisp");
+}
+
+static void instantiate_isp_i2c_client(struct amdisp_platform *ov05c10, struct i2c_adapter *adap)
+{
+ struct i2c_board_info *info = &ov05c10->board_info;
+ struct i2c_client *i2c_dev;
+
+ if (ov05c10->i2c_dev)
+ return;
+
+ if (!info->addr) {
+ dev_err(&adap->dev, "invalid i2c_addr 0x%x detected\n",
+ ov05c10->i2c_addr);
+ return;
+ }
+
+ i2c_dev = i2c_new_client_device(adap, info);
+ if (IS_ERR(i2c_dev)) {
+ dev_err(&adap->dev, "error %pe registering isp i2c_client\n",
+ i2c_dev);
+ return;
+ }
+ ov05c10->i2c_dev = i2c_dev;
+}
+
+static int isp_i2c_bus_notify(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct amdisp_platform *ov05c10 = container_of(nb, struct amdisp_platform, i2c_nb);
+ struct device *dev = data;
+ struct i2c_client *client;
+ struct i2c_adapter *adap;
+
+ switch (action) {
+ case BUS_NOTIFY_ADD_DEVICE:
+ adap = i2c_verify_adapter(dev);
+ if (!adap)
+ break;
+ if (is_isp_i2c_adapter(adap))
+ instantiate_isp_i2c_client(ov05c10, adap);
+ break;
+ case BUS_NOTIFY_REMOVED_DEVICE:
+ client = i2c_verify_client(dev);
+ if (!client)
+ break;
+ if (ov05c10->i2c_dev == client) {
+ dev_dbg(&client->adapter->dev, "amdisp i2c_client removed\n");
+ ov05c10->i2c_dev = NULL;
+ }
+ break;
+ default:
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct amdisp_platform *prepare_amdisp_platform(const struct amdisp_platform *src)
+{
+ struct amdisp_platform *isp_ov05c10;
+ const struct software_node **sw_nodes;
+ const struct software_node *sw_node;
+ struct i2c_board_info *info;
+ int ret;
+
+ isp_ov05c10 = kmemdup(src, sizeof(*isp_ov05c10), GFP_KERNEL);
+ if (!isp_ov05c10)
+ return ERR_PTR(-ENOMEM);
+
+ info = &isp_ov05c10->board_info;
+
+ sw_nodes = (const struct software_node **)src->swnodes;
+ ret = software_node_register_node_group(sw_nodes);
+ if (ret)
+ goto error_unregister_sw_node;
+
+ sw_node = (const struct software_node *)src->swnodes[0];
+ info->swnode = sw_node;
+
+ return isp_ov05c10;
+
+error_unregister_sw_node:
+ software_node_unregister_node_group(sw_nodes);
+ kfree(isp_ov05c10);
+ return ERR_PTR(ret);
+}
+
+static int amd_isp_probe(struct platform_device *pdev)
+{
+ struct amdisp_platform *ov05c10;
+ int ret;
+
+ ov05c10 = prepare_amdisp_platform(&amdisp_ov05c10_platform_config);
+ if (IS_ERR(ov05c10))
+ return dev_err_probe(&pdev->dev, PTR_ERR(ov05c10),
+ "failed to prepare amdisp platform fw node\n");
+
+ ov05c10->i2c_nb.notifier_call = isp_i2c_bus_notify;
+
+ ret = bus_register_notifier(&i2c_bus_type, &ov05c10->i2c_nb);
+ if (ret)
+ goto error_free_platform;
+
+ platform_set_drvdata(pdev, ov05c10);
+ return ret;
+
+error_free_platform:
+ kfree(ov05c10);
+ return ret;
+}
+
+static void amd_isp_remove(struct platform_device *pdev)
+{
+ struct amdisp_platform *ov05c10 = platform_get_drvdata(pdev);
+
+ if (IS_ERR_OR_NULL(ov05c10))
+ return;
+
+ bus_unregister_notifier(&i2c_bus_type, &ov05c10->i2c_nb);
+ i2c_unregister_device(ov05c10->i2c_dev);
+ software_node_unregister_node_group((const struct software_node **)
+ ov05c10->swnodes);
+ kfree(ov05c10);
+}
+
+static struct platform_driver amd_isp_platform_driver = {
+ .driver = {
+ .name = AMD_ISP_PLAT_DRV_NAME,
+ .acpi_match_table = amdisp_sensor_ids,
+ },
+ .probe = amd_isp_probe,
+ .remove = amd_isp_remove,
+};
+
+module_platform_driver(amd_isp_platform_driver);
+
+MODULE_AUTHOR("Benjamin Chan <benjamin.chan@amd.com>");
+MODULE_AUTHOR("Pratap Nirujogi <pratap.nirujogi@amd.com>");
+MODULE_DESCRIPTION("AMD ISP4 Platform Driver");
+MODULE_LICENSE("GPL");