diff options
| -rw-r--r-- | drivers/acpi/Makefile | 2 | ||||
| -rw-r--r-- | drivers/acpi/internal.h | 8 | ||||
| -rw-r--r-- | drivers/acpi/mipi-disco-img.c | 292 | ||||
| -rw-r--r-- | drivers/acpi/scan.c | 48 | ||||
| -rw-r--r-- | include/acpi/acpi_bus.h | 18 |
5 files changed, 358 insertions, 10 deletions
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index eaa09bf52f17..d367e649714f 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -37,7 +37,7 @@ acpi-$(CONFIG_ACPI_SLEEP) += proc.o # ACPI Bus and Device Drivers # acpi-y += bus.o glue.o -acpi-y += scan.o +acpi-y += scan.o mipi-disco-img.o acpi-y += resource.o acpi-y += acpi_processor.o acpi-y += processor_core.o diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 866c7c4ed233..959a2bc61916 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -276,4 +276,12 @@ void acpi_init_lpit(void); static inline void acpi_init_lpit(void) { } #endif +/*-------------------------------------------------------------------------- + ACPI _CRS CSI-2 and MIPI DisCo for Imaging + -------------------------------------------------------------------------- */ + +void acpi_mipi_check_crs_csi2(acpi_handle handle); +void acpi_mipi_scan_crs_csi2(void); +void acpi_mipi_crs_csi2_cleanup(void); + #endif /* _ACPI_INTERNAL_H_ */ diff --git a/drivers/acpi/mipi-disco-img.c b/drivers/acpi/mipi-disco-img.c new file mode 100644 index 000000000000..91281c8cb4f2 --- /dev/null +++ b/drivers/acpi/mipi-disco-img.c @@ -0,0 +1,292 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * MIPI DisCo for Imaging support. + * + * Copyright (C) 2023 Intel Corporation + * + * 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. + * + * 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. + */ + +#include <linux/acpi.h> +#include <linux/limits.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/overflow.h> +#include <linux/types.h> +#include <linux/slab.h> +#include <linux/string.h> + +#include "internal.h" + +static LIST_HEAD(acpi_mipi_crs_csi2_list); + +static void acpi_mipi_data_tag(acpi_handle handle, void *context) +{ +} + +/* Connection data extracted from one _CRS CSI-2 resource descriptor. */ +struct crs_csi2_connection { + struct list_head entry; + struct acpi_resource_csi2_serialbus csi2_data; + acpi_handle remote_handle; + char remote_name[]; +}; + +/* Data extracted from _CRS CSI-2 resource descriptors for one device. */ +struct crs_csi2 { + struct list_head entry; + acpi_handle handle; + struct acpi_device_software_nodes *swnodes; + struct list_head connections; + u32 port_count; +}; + +struct csi2_resources_walk_data { + acpi_handle handle; + struct list_head connections; +}; + +static acpi_status parse_csi2_resource(struct acpi_resource *res, void *context) +{ + struct csi2_resources_walk_data *crwd = context; + struct acpi_resource_csi2_serialbus *csi2_res; + struct acpi_resource_source *csi2_res_src; + u16 csi2_res_src_length; + struct crs_csi2_connection *conn; + acpi_handle remote_handle; + + if (res->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) + return AE_OK; + + csi2_res = &res->data.csi2_serial_bus; + + if (csi2_res->type != ACPI_RESOURCE_SERIAL_TYPE_CSI2) + return AE_OK; + + csi2_res_src = &csi2_res->resource_source; + if (ACPI_FAILURE(acpi_get_handle(NULL, csi2_res_src->string_ptr, + &remote_handle))) { + acpi_handle_debug(crwd->handle, + "unable to find resource source\n"); + return AE_OK; + } + csi2_res_src_length = csi2_res_src->string_length; + if (!csi2_res_src_length) { + acpi_handle_debug(crwd->handle, + "invalid resource source string length\n"); + return AE_OK; + } + + conn = kmalloc(struct_size(conn, remote_name, csi2_res_src_length + 1), + GFP_KERNEL); + if (!conn) + return AE_OK; + + conn->csi2_data = *csi2_res; + strscpy(conn->remote_name, csi2_res_src->string_ptr, csi2_res_src_length); + conn->csi2_data.resource_source.string_ptr = conn->remote_name; + conn->remote_handle = remote_handle; + + list_add(&conn->entry, &crwd->connections); + + return AE_OK; +} + +static struct crs_csi2 *acpi_mipi_add_crs_csi2(acpi_handle handle, + struct list_head *list) +{ + struct crs_csi2 *csi2; + + csi2 = kzalloc(sizeof(*csi2), GFP_KERNEL); + if (!csi2) + return NULL; + + csi2->handle = handle; + INIT_LIST_HEAD(&csi2->connections); + csi2->port_count = 1; + + if (ACPI_FAILURE(acpi_attach_data(handle, acpi_mipi_data_tag, csi2))) { + kfree(csi2); + return NULL; + } + + list_add(&csi2->entry, list); + + return csi2; +} + +static struct crs_csi2 *acpi_mipi_get_crs_csi2(acpi_handle handle) +{ + struct crs_csi2 *csi2; + + if (ACPI_FAILURE(acpi_get_data_full(handle, acpi_mipi_data_tag, + (void **)&csi2, NULL))) + return NULL; + + return csi2; +} + +static void csi_csr2_release_connections(struct list_head *list) +{ + struct crs_csi2_connection *conn, *conn_tmp; + + list_for_each_entry_safe(conn, conn_tmp, list, entry) { + list_del(&conn->entry); + kfree(conn); + } +} + +static void acpi_mipi_del_crs_csi2(struct crs_csi2 *csi2) +{ + list_del(&csi2->entry); + acpi_detach_data(csi2->handle, acpi_mipi_data_tag); + kfree(csi2->swnodes); + csi_csr2_release_connections(&csi2->connections); + kfree(csi2); +} + +/** + * acpi_mipi_check_crs_csi2 - Look for CSI-2 resources in _CRS + * @handle: Device object handle to evaluate _CRS for. + * + * Find all CSI-2 resource descriptors in the given device's _CRS + * and collect them into a list. + */ +void acpi_mipi_check_crs_csi2(acpi_handle handle) +{ + struct csi2_resources_walk_data crwd = { + .handle = handle, + .connections = LIST_HEAD_INIT(crwd.connections), + }; + struct crs_csi2 *csi2; + + /* + * Avoid allocating _CRS CSI-2 objects for devices without any CSI-2 + * resource descriptions in _CRS to reduce overhead. + */ + acpi_walk_resources(handle, METHOD_NAME__CRS, parse_csi2_resource, &crwd); + if (list_empty(&crwd.connections)) + return; + + /* + * Create a _CRS CSI-2 entry to store the extracted connection + * information and add it to the global list. + */ + csi2 = acpi_mipi_add_crs_csi2(handle, &acpi_mipi_crs_csi2_list); + if (!csi2) { + csi_csr2_release_connections(&crwd.connections); + return; /* Nothing really can be done about this. */ + } + + list_replace(&crwd.connections, &csi2->connections); +} + +#define NO_CSI2_PORT (UINT_MAX - 1) + +static void alloc_crs_csi2_swnodes(struct crs_csi2 *csi2) +{ + size_t port_count = csi2->port_count; + struct acpi_device_software_nodes *swnodes; + size_t alloc_size; + unsigned int i; + + /* + * Allocate memory for ports, node pointers (number of nodes + + * 1 (guardian), nodes (root + number of ports * 2 (because for + * every port there is an endpoint)). + */ + if (check_mul_overflow(sizeof(*swnodes->ports) + + sizeof(*swnodes->nodes) * 2 + + sizeof(*swnodes->nodeptrs) * 2, + port_count, &alloc_size) || + check_add_overflow(sizeof(*swnodes) + + sizeof(*swnodes->nodes) + + sizeof(*swnodes->nodeptrs) * 2, + alloc_size, &alloc_size)) { + acpi_handle_info(csi2->handle, + "too many _CRS CSI-2 resource handles (%zu)", + port_count); + return; + } + + swnodes = kmalloc(alloc_size, GFP_KERNEL); + if (!swnodes) + return; + + swnodes->ports = (struct acpi_device_software_node_port *)(swnodes + 1); + swnodes->nodes = (struct software_node *)(swnodes->ports + port_count); + swnodes->nodeptrs = (const struct software_node **)(swnodes->nodes + 1 + + 2 * port_count); + swnodes->num_ports = port_count; + + for (i = 0; i < 2 * port_count + 1; i++) + swnodes->nodeptrs[i] = &swnodes->nodes[i]; + + swnodes->nodeptrs[i] = NULL; + + for (i = 0; i < port_count; i++) + swnodes->ports[i].port_nr = NO_CSI2_PORT; + + csi2->swnodes = swnodes; +} + +/** + * acpi_mipi_scan_crs_csi2 - Create ACPI _CRS CSI-2 software nodes + * + * Note that this function must be called before any struct acpi_device objects + * are bound to any ACPI drivers or scan handlers, so it cannot assume the + * existence of struct acpi_device objects for every device present in the ACPI + * namespace. + * + * acpi_scan_lock in scan.c must be held when calling this function. + */ +void acpi_mipi_scan_crs_csi2(void) +{ + struct crs_csi2 *csi2; + LIST_HEAD(aux_list); + + /* Count references to each ACPI handle in the CSI-2 connection graph. */ + list_for_each_entry(csi2, &acpi_mipi_crs_csi2_list, entry) { + struct crs_csi2_connection *conn; + + list_for_each_entry(conn, &csi2->connections, entry) { + struct crs_csi2 *remote_csi2; + + csi2->port_count++; + + remote_csi2 = acpi_mipi_get_crs_csi2(conn->remote_handle); + if (remote_csi2) { + remote_csi2->port_count++; + continue; + } + /* + * The remote endpoint has no _CRS CSI-2 list entry yet, + * so create one for it and add it to the list. + */ + acpi_mipi_add_crs_csi2(conn->remote_handle, &aux_list); + } + } + list_splice(&aux_list, &acpi_mipi_crs_csi2_list); + + /* Allocate software nodes for representing the CSI-2 information. */ + list_for_each_entry(csi2, &acpi_mipi_crs_csi2_list, entry) + alloc_crs_csi2_swnodes(csi2); +} + +/** + * acpi_mipi_crs_csi2_cleanup - Free _CRS CSI-2 temporary data + */ +void acpi_mipi_crs_csi2_cleanup(void) +{ + struct crs_csi2 *csi2, *csi2_tmp; + + list_for_each_entry_safe(csi2, csi2_tmp, &acpi_mipi_crs_csi2_list, entry) + acpi_mipi_del_crs_csi2(csi2); +} diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index fa5dd71a80fa..8e12c558b8db 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1976,7 +1976,7 @@ static void acpi_scan_init_hotplug(struct acpi_device *adev) } } -static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep) +static u32 acpi_scan_check_dep(acpi_handle handle) { struct acpi_handle_list dep_devices; acpi_status status; @@ -1989,8 +1989,7 @@ static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep) * 2. ACPI nodes describing USB ports. * Still, checking for _HID catches more then just these cases ... */ - if (!check_dep || !acpi_has_method(handle, "_DEP") || - !acpi_has_method(handle, "_HID")) + if (!acpi_has_method(handle, "_DEP") || !acpi_has_method(handle, "_HID")) return 0; status = acpi_evaluate_reference(handle, "_DEP", NULL, &dep_devices); @@ -2036,7 +2035,13 @@ static u32 acpi_scan_check_dep(acpi_handle handle, bool check_dep) return count; } -static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep, +static acpi_status acpi_scan_check_crs_csi2_cb(acpi_handle handle, u32 a, void *b, void **c) +{ + acpi_mipi_check_crs_csi2(handle); + return AE_OK; +} + +static acpi_status acpi_bus_check_add(acpi_handle handle, bool first_pass, struct acpi_device **adev_p) { struct acpi_device *device = acpi_fetch_acpi_dev(handle); @@ -2054,9 +2059,25 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep, if (acpi_device_should_be_hidden(handle)) return AE_OK; - /* Bail out if there are dependencies. */ - if (acpi_scan_check_dep(handle, check_dep) > 0) - return AE_CTRL_DEPTH; + if (first_pass) { + acpi_mipi_check_crs_csi2(handle); + + /* Bail out if there are dependencies. */ + if (acpi_scan_check_dep(handle) > 0) { + /* + * The entire CSI-2 connection graph needs to be + * extracted before any drivers or scan handlers + * are bound to struct device objects, so scan + * _CRS CSI-2 resource descriptors for all + * devices below the current handle. + */ + acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, + ACPI_UINT32_MAX, + acpi_scan_check_crs_csi2_cb, + NULL, NULL, NULL); + return AE_CTRL_DEPTH; + } + } fallthrough; case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */ @@ -2079,10 +2100,10 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep, } /* - * If check_dep is true at this point, the device has no dependencies, + * If first_pass is true at this point, the device has no dependencies, * or the creation of the device object would have been postponed above. */ - acpi_add_single_object(&device, handle, type, !check_dep); + acpi_add_single_object(&device, handle, type, !first_pass); if (!device) return AE_CTRL_DEPTH; @@ -2494,12 +2515,21 @@ int acpi_bus_scan(acpi_handle handle) if (!device) return -ENODEV; + /* + * Allocate ACPI _CRS CSI-2 software nodes using information extracted + * from the _CRS CSI-2 resource descriptors during the ACPI namespace + * walk above. + */ + acpi_mipi_scan_crs_csi2(); + acpi_bus_attach(device, (void *)true); /* Pass 2: Enumerate all of the remaining devices. */ acpi_scan_postponed(); + acpi_mipi_crs_csi2_cleanup(); + return 0; } EXPORT_SYMBOL(acpi_bus_scan); diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index afeed6e72049..f122fa1c10a8 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -366,6 +366,24 @@ struct acpi_device_data { struct acpi_gpio_mapping; +struct acpi_device_software_node_port { + unsigned int port_nr; +}; + +/** + * struct acpi_device_software_nodes - Software nodes for an ACPI device + * @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 software_node *nodes; + const struct software_node **nodeptrs; + struct acpi_device_software_node_port *ports; + unsigned int num_ports; +}; + /* Device */ struct acpi_device { u32 pld_crc; |