ACPI: scan: Extract MIPI DisCo for Imaging data into swnodes
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>
Tue, 7 Nov 2023 19:19:42 +0000 (20:19 +0100)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Mon, 20 Nov 2023 15:50:48 +0000 (16:50 +0100)
Add information extracted from the MIPI DisCo for Imaging device
properties to software nodes created during the CSI-2 connection graph
discovery.

Link: https://www.mipi.org/specifications/mipi-disco-imaging
Co-developed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Sakari Ailus <sakari.ailus@linux.intel.com>
drivers/acpi/internal.h
drivers/acpi/mipi-disco-img.c
drivers/acpi/scan.c
include/acpi/acpi_bus.h

index 959a2bc6191668cd6fb0d1c95091f5ef1ada9fd8..86b670637f2f48a090b1dcb01a8b21591db168b5 100644 (file)
@@ -282,6 +282,7 @@ static inline void acpi_init_lpit(void) { }
 
 void acpi_mipi_check_crs_csi2(acpi_handle handle);
 void acpi_mipi_scan_crs_csi2(void);
+void acpi_mipi_init_crs_csi2_swnodes(void);
 void acpi_mipi_crs_csi2_cleanup(void);
 
 #endif /* _ACPI_INTERNAL_H_ */
index 5ff72d83fad2faeecf9573ee5c73efae86362495..dcbaba91d4fece18033480c468d236282f693f23 100644 (file)
@@ -6,12 +6,16 @@
  *
  * Support MIPI DisCo for Imaging by parsing ACPI _CRS CSI-2 records defined in
  * Section 6.4.3.8.2.4 "Camera Serial Interface (CSI-2) Connection Resource
- * Descriptor" of ACPI 6.5.
+ * Descriptor" of ACPI 6.5 and using device properties defined by the MIPI DisCo
+ * for Imaging specification.
  *
  * The implementation looks for the information in the ACPI namespace (CSI-2
  * resource descriptors in _CRS) and constructs software nodes compatible with
  * Documentation/firmware-guide/acpi/dsd/graph.rst to represent the CSI-2
- * connection graph.
+ * connection graph.  The software nodes are then populated with the data
+ * extracted from the _CRS CSI-2 resource descriptors and the MIPI DisCo
+ * for Imaging device properties present in _DSD for the ACPI device objects
+ * with CSI-2 connections.
  */
 
 #include <linux/acpi.h>
@@ -431,6 +435,250 @@ void acpi_mipi_scan_crs_csi2(void)
                prepare_crs_csi2_swnodes(csi2);
 }
 
+/*
+ * Get the index of the next property in the property array, with a given
+ * maximum value.
+ */
+#define NEXT_PROPERTY(index, max)                      \
+       (WARN_ON((index) > ACPI_DEVICE_SWNODE_##max) ?  \
+        ACPI_DEVICE_SWNODE_##max : (index)++)
+
+static void init_csi2_port_local(struct acpi_device *adev,
+                                struct acpi_device_software_node_port *port,
+                                struct fwnode_handle *port_fwnode,
+                                unsigned int index)
+{
+       acpi_handle handle = acpi_device_handle(adev);
+       unsigned int num_link_freqs;
+       int ret;
+
+       ret = fwnode_property_count_u64(port_fwnode, "mipi-img-link-frequencies");
+       if (ret <= 0)
+               return;
+
+       num_link_freqs = ret;
+       if (num_link_freqs > ACPI_DEVICE_CSI2_DATA_LANES) {
+               acpi_handle_info(handle, "Too many link frequencies: %u\n",
+                                num_link_freqs);
+               num_link_freqs = ACPI_DEVICE_CSI2_DATA_LANES;
+       }
+
+       ret = fwnode_property_read_u64_array(port_fwnode,
+                                            "mipi-img-link-frequencies",
+                                            port->link_frequencies,
+                                            num_link_freqs);
+       if (ret) {
+               acpi_handle_info(handle, "Unable to get link frequencies (%d)\n",
+                                ret);
+               return;
+       }
+
+       port->ep_props[NEXT_PROPERTY(index, EP_LINK_FREQUENCIES)] =
+                               PROPERTY_ENTRY_U64_ARRAY_LEN("link-frequencies",
+                                                            port->link_frequencies,
+                                                            num_link_freqs);
+}
+
+static void init_csi2_port(struct acpi_device *adev,
+                          struct acpi_device_software_nodes *swnodes,
+                          struct acpi_device_software_node_port *port,
+                          struct fwnode_handle *port_fwnode,
+                          unsigned int port_index)
+{
+       unsigned int ep_prop_index = ACPI_DEVICE_SWNODE_EP_CLOCK_LANES;
+       acpi_handle handle = acpi_device_handle(adev);
+       u8 val[ACPI_DEVICE_CSI2_DATA_LANES];
+       int num_lanes = 0;
+       int ret;
+
+       if (GRAPH_PORT_NAME(port->port_name, port->port_nr))
+               return;
+
+       swnodes->nodes[ACPI_DEVICE_SWNODE_PORT(port_index)] =
+                       SOFTWARE_NODE(port->port_name, port->port_props,
+                                     &swnodes->nodes[ACPI_DEVICE_SWNODE_ROOT]);
+
+       ret = fwnode_property_read_u8(port_fwnode, "mipi-img-clock-lane", val);
+       if (!ret)
+               port->ep_props[NEXT_PROPERTY(ep_prop_index, EP_CLOCK_LANES)] =
+                       PROPERTY_ENTRY_U32("clock-lanes", val[0]);
+
+       ret = fwnode_property_count_u8(port_fwnode, "mipi-img-data-lanes");
+       if (ret > 0) {
+               num_lanes = ret;
+
+               if (num_lanes > ACPI_DEVICE_CSI2_DATA_LANES) {
+                       acpi_handle_info(handle, "Too many data lanes: %u\n",
+                                        num_lanes);
+                       num_lanes = ACPI_DEVICE_CSI2_DATA_LANES;
+               }
+
+               ret = fwnode_property_read_u8_array(port_fwnode,
+                                                   "mipi-img-data-lanes",
+                                                   val, num_lanes);
+               if (!ret) {
+                       unsigned int i;
+
+                       for (i = 0; i < num_lanes; i++)
+                               port->data_lanes[i] = val[i];
+
+                       port->ep_props[NEXT_PROPERTY(ep_prop_index, EP_DATA_LANES)] =
+                               PROPERTY_ENTRY_U32_ARRAY_LEN("data-lanes",
+                                                            port->data_lanes,
+                                                            num_lanes);
+               }
+       }
+
+       ret = fwnode_property_count_u8(port_fwnode, "mipi-img-lane-polarities");
+       if (ret < 0) {
+               acpi_handle_debug(handle, "Lane polarity bytes missing\n");
+       } else if (ret * BITS_PER_TYPE(u8) < num_lanes + 1) {
+               acpi_handle_info(handle, "Too few lane polarity bytes (%lu vs. %d)\n",
+                                ret * BITS_PER_TYPE(u8), num_lanes + 1);
+       } else {
+               unsigned long mask = 0;
+               int byte_count = ret;
+               unsigned int i;
+
+               /*
+                * The total number of lanes is ACPI_DEVICE_CSI2_DATA_LANES + 1
+                * (data lanes + clock lane).  It is not expected to ever be
+                * greater than the number of bits in an unsigned long
+                * variable, but ensure that this is the case.
+                */
+               BUILD_BUG_ON(BITS_PER_TYPE(unsigned long) <= ACPI_DEVICE_CSI2_DATA_LANES);
+
+               if (byte_count > sizeof(mask)) {
+                       acpi_handle_info(handle, "Too many lane polarities: %d\n",
+                                        byte_count);
+                       byte_count = sizeof(mask);
+               }
+               fwnode_property_read_u8_array(port_fwnode, "mipi-img-lane-polarities",
+                                             val, byte_count);
+
+               for (i = 0; i < byte_count; i++)
+                       mask |= (unsigned long)val[i] << BITS_PER_TYPE(u8) * i;
+
+               for (i = 0; i <= num_lanes; i++)
+                       port->lane_polarities[i] = test_bit(i, &mask);
+
+               port->ep_props[NEXT_PROPERTY(ep_prop_index, EP_LANE_POLARITIES)] =
+                               PROPERTY_ENTRY_U32_ARRAY_LEN("lane-polarities",
+                                                            port->lane_polarities,
+                                                            num_lanes + 1);
+       }
+
+       swnodes->nodes[ACPI_DEVICE_SWNODE_EP(port_index)] =
+               SOFTWARE_NODE("endpoint@0", swnodes->ports[port_index].ep_props,
+                             &swnodes->nodes[ACPI_DEVICE_SWNODE_PORT(port_index)]);
+
+       if (port->crs_csi2_local)
+               init_csi2_port_local(adev, port, port_fwnode, ep_prop_index);
+}
+
+#define MIPI_IMG_PORT_PREFIX "mipi-img-port-"
+
+static struct fwnode_handle *get_mipi_port_handle(struct fwnode_handle *adev_fwnode,
+                                                 unsigned int port_nr)
+{
+       char port_name[sizeof(MIPI_IMG_PORT_PREFIX) + 2];
+
+       if (snprintf(port_name, sizeof(port_name), "%s%u",
+                    MIPI_IMG_PORT_PREFIX, port_nr) >= sizeof(port_name))
+               return NULL;
+
+       return fwnode_get_named_child_node(adev_fwnode, port_name);
+}
+
+static void init_crs_csi2_swnodes(struct crs_csi2 *csi2)
+{
+       struct acpi_buffer buffer = { .length = ACPI_ALLOCATE_BUFFER };
+       struct acpi_device_software_nodes *swnodes = csi2->swnodes;
+       acpi_handle handle = csi2->handle;
+       struct fwnode_handle *adev_fwnode;
+       struct acpi_device *adev;
+       acpi_status status;
+       unsigned int i;
+       int ret;
+
+       /*
+        * Bail out if the swnodes are not available (either they have not been
+        * allocated or they have been assigned to the device already).
+        */
+       if (!swnodes)
+               return;
+
+       adev = acpi_fetch_acpi_dev(handle);
+       if (!adev)
+               return;
+
+       adev_fwnode = acpi_fwnode_handle(adev);
+
+       status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
+       if (ACPI_FAILURE(status)) {
+               acpi_handle_info(handle, "Unable to get the path name\n");
+               return;
+       }
+
+       swnodes->nodes[ACPI_DEVICE_SWNODE_ROOT] =
+                       SOFTWARE_NODE(buffer.pointer, swnodes->dev_props, NULL);
+
+       for (i = 0; i < swnodes->num_ports; i++) {
+               struct acpi_device_software_node_port *port = &swnodes->ports[i];
+               struct fwnode_handle *port_fwnode;
+
+               /*
+                * The MIPI DisCo for Imaging specification defines _DSD device
+                * properties for providing CSI-2 port parameters that can be
+                * accessed through the generic device properties framework.  To
+                * access them, it is first necessary to find the data node
+                * representing the port under the given ACPI device object.
+                */
+               port_fwnode = get_mipi_port_handle(adev_fwnode, port->port_nr);
+               if (!port_fwnode) {
+                       acpi_handle_info(handle,
+                                        "MIPI port name too long for port %u\n",
+                                        port->port_nr);
+                       continue;
+               }
+
+               init_csi2_port(adev, swnodes, port, port_fwnode, i);
+
+               fwnode_handle_put(port_fwnode);
+       }
+
+       ret = software_node_register_node_group(swnodes->nodeptrs);
+       if (ret < 0) {
+               acpi_handle_info(handle,
+                                "Unable to register software nodes (%d)\n", ret);
+               return;
+       }
+
+       adev->swnodes = swnodes;
+       adev_fwnode->secondary = software_node_fwnode(swnodes->nodes);
+
+       /*
+        * Prevents the swnodes from this csi2 entry from being assigned again
+        * or freed prematurely.
+        */
+       csi2->swnodes = NULL;
+}
+
+/**
+ * acpi_mipi_init_crs_csi2_swnodes - Initialize _CRS CSI-2 software nodes
+ *
+ * Use MIPI DisCo for Imaging device properties to finalize the initialization
+ * of CSI-2 software nodes for all ACPI device objects that have been already
+ * enumerated.
+ */
+void acpi_mipi_init_crs_csi2_swnodes(void)
+{
+       struct crs_csi2 *csi2, *csi2_tmp;
+
+       list_for_each_entry_safe(csi2, csi2_tmp, &acpi_mipi_crs_csi2_list, entry)
+               init_crs_csi2_swnodes(csi2);
+}
+
 /**
  * acpi_mipi_crs_csi2_cleanup - Free _CRS CSI-2 temporary data
  */
index 8e12c558b8db7c42edda557119d016ce9ed8c53b..b8df047799049650ffc97343d365bd3cdcb9f014 100644 (file)
@@ -2447,6 +2447,13 @@ static void acpi_scan_postponed_branch(acpi_handle handle)
 
        acpi_walk_namespace(ACPI_TYPE_ANY, handle, ACPI_UINT32_MAX,
                            acpi_bus_check_add_2, NULL, NULL, (void **)&adev);
+
+       /*
+        * Populate the ACPI _CRS CSI-2 software nodes for the ACPI devices that
+        * have been added above.
+        */
+       acpi_mipi_init_crs_csi2_swnodes();
+
        acpi_bus_attach(adev, NULL);
 }
 
@@ -2516,11 +2523,12 @@ int acpi_bus_scan(acpi_handle handle)
                return -ENODEV;
 
        /*
-        * Allocate ACPI _CRS CSI-2 software nodes using information extracted
+        * Set up ACPI _CRS CSI-2 software nodes using information extracted
         * from the _CRS CSI-2 resource descriptors during the ACPI namespace
-        * walk above.
+        * walk above and MIPI DisCo for Imaging device properties.
         */
        acpi_mipi_scan_crs_csi2();
+       acpi_mipi_init_crs_csi2_swnodes();
 
        acpi_bus_attach(device, (void *)true);
 
index a7fa24f1af4606efe49d42eed8688b846d7ac71b..c299fb974e49697fa4a53031707da4bf54d6a811 100644 (file)
@@ -366,10 +366,24 @@ struct acpi_device_data {
 
 struct acpi_gpio_mapping;
 
+#define ACPI_DEVICE_SWNODE_ROOT                        0
+
+/*
+ * The maximum expected number of CSI-2 data lanes.
+ *
+ * This number is not expected to ever have to be equal to or greater than the
+ * number of bits in an unsigned long variable, but if it needs to be increased
+ * above that limit, code will need to be adjusted accordingly.
+ */
 #define ACPI_DEVICE_CSI2_DATA_LANES            8
 
 #define ACPI_DEVICE_SWNODE_PORT_NAME_LENGTH    8
 
+enum acpi_device_swnode_dev_props {
+       ACPI_DEVICE_SWNODE_DEV_NUM_OF,
+       ACPI_DEVICE_SWNODE_DEV_NUM_ENTRIES
+};
+
 enum acpi_device_swnode_port_props {
        ACPI_DEVICE_SWNODE_PORT_REG,
        ACPI_DEVICE_SWNODE_PORT_NUM_OF,
@@ -425,12 +439,14 @@ struct acpi_device_software_node_port {
 
 /**
  * struct acpi_device_software_nodes - Software nodes for an ACPI device
+ * @dev_props: Device properties.
  * @nodes: Software nodes for root as well as ports and endpoints.
  * @nodeprts: Array of software node pointers, for (un)registering them.
  * @ports: Information related to each port and endpoint within a port.
  * @num_ports: The number of ports.
  */
 struct acpi_device_software_nodes {
+       struct property_entry dev_props[ACPI_DEVICE_SWNODE_DEV_NUM_ENTRIES];
        struct software_node *nodes;
        const struct software_node **nodeptrs;
        struct acpi_device_software_node_port *ports;
@@ -455,6 +471,7 @@ struct acpi_device {
        struct acpi_device_data data;
        struct acpi_scan_handler *handler;
        struct acpi_hotplug_context *hp;
+       struct acpi_device_software_nodes *swnodes;
        const struct acpi_gpio_mapping *driver_gpios;
        void *driver_data;
        struct device dev;