Parse newly added ACPI _CRS CSI-2 descriptor for CSI-2 and camera
configuration, associate it with appropriate devices and allocate memory for
software nodes needed to create a DT-like data structure for drivers.
Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
---
drivers/acpi/Makefile | 2 +-
drivers/acpi/internal.h | 27 ++++
drivers/acpi/mipi.c | 343 ++++++++++++++++++++++++++++++++++++++++
drivers/acpi/scan.c | 50 ++++--
include/acpi/acpi_bus.h | 11 ++
5 files changed, 418 insertions(+), 15 deletions(-)
create mode 100644 drivers/acpi/mipi.c
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index a5b649e71ab1..a98fa1bc1554 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.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 06ad497067ac..aa5f9c69dbbe 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -102,6 +102,24 @@ struct acpi_device_bus_id {
struct list_head node;
};
+/* Context for scanning ACPI device nodes for _CRS CSI2 resource descriptors */
+struct acpi_scan_context_csi2 {
+ struct list_head crs_csi2_head;
+ size_t handle_count;
+};
+
+/**
+ * struct acpi_scan_context - Context for scanning ACPI devices
+ * @postponed_head: The list head of the postponed ACPI handles
+ * @device: The first encountered device, typically the root of the scanned tree
+ * @csi2: Context for scanning _CRS CSI2 resource descriptors
+ */
+struct acpi_scan_context {
+ struct list_head postponed_head;
+ struct acpi_device *device;
+ struct acpi_scan_context_csi2 csi2;
+};
+
void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
int type, void (*release)(struct device *));
int acpi_tie_acpi_dev(struct acpi_device *adev);
@@ -282,4 +300,13 @@ void acpi_init_lpit(void);
static inline void acpi_init_lpit(void) { }
#endif
+/*--------------------------------------------------------------------------
+ ACPI _CRS CSI2 and MIPI DisCo for Imaging conversion
+ -------------------------------------------------------------------------- */
+
+void acpi_crs_csi2_swnodes_del_free(void);
+void acpi_bus_scan_check_crs_csi2(acpi_handle handle, struct acpi_scan_context *ctx);
+void acpi_bus_scan_crs_csi2_release(struct list_head *crs_csi2_handles);
+void acpi_bus_scan_crs_csi2(struct acpi_scan_context_csi2 *ctx);
+
#endif /* _ACPI_INTERNAL_H_ */
diff --git a/drivers/acpi/mipi.c b/drivers/acpi/mipi.c
new file mode 100644
index 000000000000..d719c879eb83
--- /dev/null
+++ b/drivers/acpi/mipi.c
@@ -0,0 +1,343 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * MIPI DisCo for Imaging support.
+ *
+ * Support MIPI DisCo for Imaging by parsing ACPI _CRS CSI2 records and DisCo
+ * for Imaging data structures.
+ *
+ * Also see <URL:https://www.mipi.org/specifications/mipi-disco-imaging>.
+ *
+ * Copyright (C) 2023 Intel Corporation
+ */
+
+#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/sort.h>
+#include <linux/string.h>
+
+#include "internal.h"
+
+/* Temporary ACPI device handle to software node data structure mapping */
+struct crs_csi2_swnodes {
+ struct list_head list;
+ acpi_handle handle;
+ struct acpi_device_software_nodes *ads;
+};
+
+static LIST_HEAD(crs_csi2_swnodes);
+
+static void crs_csi2_swnode_del_free(struct crs_csi2_swnodes *swnodes)
+{
+ list_del(&swnodes->list);
+ kfree(swnodes);
+}
+
+void acpi_crs_csi2_swnodes_del_free(void)
+{
+ struct crs_csi2_swnodes *swnodes, *swnodes_tmp;
+
+ list_for_each_entry_safe(swnodes, swnodes_tmp, &crs_csi2_swnodes, list)
+ crs_csi2_swnode_del_free(swnodes);
+}
+
+/*
+ * Description of a _CRS CSI2 resource descriptor before software node creation
+ */
+struct crs_csi2_instance {
+ struct list_head list;
+ struct acpi_resource_csi2_serialbus csi2;
+ acpi_handle remote_handle;
+ char remote_name[];
+};
+
+/* Temporary list of ACPI device nodes with _CRS CSI2 resource descriptors */
+struct crs_csi2 {
+ struct list_head list;
+ acpi_handle handle;
+ struct list_head buses;
+};
+
+/*
+ * Context for collecting _CRS CSI2 resource descriptors during ACPI namespace
+ * walk
+ */
+struct scan_check_crs_csi2_context {
+ struct list_head res_head;
+ acpi_handle handle;
+ size_t handle_count;
+};
+
+/* Scan a single CSI2 resource descriptor in _CRS. */
+static acpi_status scan_check_crs_csi2_instance(struct acpi_resource *res,
+ void *context)
+{
+ struct scan_check_crs_csi2_context *inst_context = context;
+ struct acpi_resource_csi2_serialbus *csi2;
+ struct crs_csi2_instance *inst;
+ acpi_handle remote_handle;
+
+ if (res->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
+ return AE_OK;
+
+ csi2 = &res->data.csi2_serial_bus;
+
+ if (csi2->type != ACPI_RESOURCE_SERIAL_TYPE_CSI2)
+ return AE_OK;
+
+ if (!csi2->resource_source.string_length) {
+ acpi_handle_debug(inst_context->handle,
+ "invalid resource source string length\n");
+ return AE_OK;
+ }
+
+ if (ACPI_FAILURE(acpi_get_handle(NULL, csi2->resource_source.string_ptr,
+ &remote_handle))) {
+ acpi_handle_warn(inst_context->handle,
+ "cannot get handle for %s\n",
+ csi2->resource_source.string_ptr);
+ return AE_OK;
+ }
+
+ /*
+ * Allocate space to store the _CRS CSI2 entry and its data and add it
+ * to the list.
+ */
+ inst = kmalloc(struct_size(inst, remote_name, csi2->resource_source.string_length),
+ GFP_KERNEL);
+ if (!inst)
+ return AE_OK;
+
+ inst->csi2 = *csi2;
+ strscpy(inst->remote_name, csi2->resource_source.string_ptr,
+ csi2->resource_source.string_length);
+ inst->csi2.resource_source.string_ptr = inst->remote_name;
+ inst->remote_handle = remote_handle;
+
+ list_add(&inst->list, &inst_context->res_head);
+
+ inst_context->handle_count++;
+
+ return AE_OK;
+}
+
+/*
+ * Find all devices with _CRS CSI2 resource descriptors and collect them
+ * into a list for later use.
+ */
+void acpi_bus_scan_check_crs_csi2(acpi_handle handle, struct acpi_scan_context *ctx)
+{
+ struct scan_check_crs_csi2_context inst_context = {
+ .handle = handle,
+ .res_head = LIST_HEAD_INIT(inst_context.res_head),
+ };
+ struct crs_csi2 *csi2;
+
+ acpi_walk_resources(handle, METHOD_NAME__CRS,
+ scan_check_crs_csi2_instance, &inst_context);
+
+ if (list_empty(&inst_context.res_head))
+ return;
+
+ /*
+ * Found entry, so allocate memory for it, fill it and add it to the
+ * list.
+ */
+ csi2 = kmalloc(sizeof(*csi2), GFP_KERNEL);
+ if (!csi2)
+ return; /* There's nothing we really can do about this. */
+
+ csi2->handle = handle;
+ list_replace(&inst_context.res_head, &csi2->buses);
+ list_add(&csi2->list, &ctx->csi2.crs_csi2_head);
+
+ /* This handle plus remote handles in _CRS CSI2 resource descriptors */
+ ctx->csi2.handle_count += 1 + inst_context.handle_count;
+}
+
+struct acpi_handle_ref {
+ acpi_handle handle;
+ unsigned int count;
+};
+
+#define NO_CSI2_PORT (UINT_MAX - 1)
+
+static int crs_handle_cmp(const void *__a, const void *__b)
+{
+ const struct acpi_handle_ref *a = __a, *b = __b;
+
+ return a->handle < b->handle ? -1 : a->handle > b->handle;
+}
+
+/*
+ * Release entries in temporary storage of ACPI device nodes with _CRS CSI2
+ * resource descriptors.
+ */
+void acpi_bus_scan_crs_csi2_release(struct list_head *crs_csi2_handles)
+{
+ struct crs_csi2 *csi2, *csi2_tmp;
+
+ list_for_each_entry_safe(csi2, csi2_tmp, crs_csi2_handles, list) {
+ struct crs_csi2_instance *inst, *inst_tmp;
+
+ list_for_each_entry_safe(inst, inst_tmp, &csi2->buses, list) {
+ list_del(&inst->list);
+ kfree(inst);
+ }
+
+ list_del(&csi2->list);
+ kfree(csi2);
+ }
+}
+
+/*
+ * Allocate memory and set up software nodes for an ACPI device with given
+ * number of CSI-2 ports.
+ */
+static void acpi_crs_csi2_alloc_fill_swnodes(size_t ports_count, acpi_handle handle)
+{
+ struct acpi_device_software_nodes *ads;
+ struct crs_csi2_swnodes *swnodes;
+ size_t alloc_size;
+ unsigned int i;
+ bool overflow;
+ void *end;
+
+ /*
+ * 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)).
+ */
+ overflow = check_mul_overflow(sizeof(*ads->ports) +
+ sizeof(*ads->nodes) * 2 +
+ sizeof(*ads->nodeptrs) * 2,
+ ports_count, &alloc_size);
+ overflow = overflow ||
+ check_add_overflow(sizeof(*ads) + sizeof(*ads->nodes) +
+ sizeof(*ads->nodeptrs) * 2,
+ alloc_size, &alloc_size);
+ if (overflow) {
+ acpi_handle_warn(handle,
+ "too many _CRS CSI2 resource handles (%zu)",
+ ports_count);
+ return;
+ }
+
+ swnodes = kzalloc(sizeof(*swnodes), GFP_KERNEL);
+ ads = kmalloc(alloc_size, GFP_KERNEL);
+ if (!swnodes || !ads)
+ goto out_free;
+
+ ads->ports = (void *)(ads + 1);
+ ads->nodes = (void *)(ads->ports + ports_count);
+ ads->nodeptrs = (void *)(ads->nodes + ports_count * 2 + 1);
+ end = ads->nodeptrs + ports_count * 2 + 2;
+ if (WARN_ON((void *)ads + alloc_size != end))
+ goto out_free;
+
+ ads->num_ports = ports_count;
+ for (i = 0; i < ports_count * 2 + 1; i++)
+ ads->nodeptrs[i] = &ads->nodes[i];
+ ads->nodeptrs[i] = NULL;
+ for (i = 0; i < ports_count; i++)
+ ads->ports[i].port_nr = NO_CSI2_PORT;
+ swnodes->handle = handle;
+ swnodes->ads = ads;
+ list_add(&swnodes->list, &crs_csi2_swnodes);
+
+ return;
+
+out_free:
+ kfree(swnodes);
+ kfree(ads);
+ acpi_handle_debug(handle, "cannot allocate for %zu software nodes\n",
+ ports_count);
+}
+
+/**
+ * acpi_bus_scan_crs_csi2 - Construct software nodes out of ACPI _CRS CSI2
+ * resource descriptors
+ * @ctx: ACPI _CRS CSI2 context, gathered during tree walk earlier
+ *
+ * This function does a number of things:
+ *
+ * 1. Count how many references to other devices _CRS CSI-2 instances have in
+ * total.
+ *
+ * 2. Count the number of references to other devices for each _CRS CSI-2
+ * instance.
+ *
+ * 3. Allocate memory for swnodes each ACPI device requires later on, and
+ * generate a list of such allocations.
+ *
+ * Note that struct acpi_device may not be available yet at this time.
+ *
+ * acpi_scan_lock in scan.c must be held when calling this function.
+ */
+void acpi_bus_scan_crs_csi2(struct acpi_scan_context_csi2 *ctx)
+{
+ struct acpi_handle_ref *handle_refs;
+ struct acpi_handle_ref *this = NULL;
+ size_t this_count;
+ unsigned int curr = 0;
+ struct crs_csi2 *csi2;
+
+ /* No handles? Bail out here. */
+ if (!ctx->handle_count)
+ return;
+
+ handle_refs = kcalloc(ctx->handle_count + 1, sizeof(*handle_refs),
+ GFP_KERNEL);
+ if (!handle_refs) {
+ pr_debug("no memory for %zu handle refs\n",
+ ctx->handle_count + 1);
+ return;
+ }
+
+ /* Associate handles to the number of references. */
+ list_for_each_entry(csi2, &ctx->crs_csi2_head, list) {
+ struct crs_csi2_instance *inst;
+ struct acpi_handle_ref *handle_ref;
+
+ handle_ref = &handle_refs[curr++];
+ handle_ref->handle = csi2->handle;
+
+ list_for_each_entry(inst, &csi2->buses, list) {
+ handle_refs[curr].handle = inst->remote_handle;
+ handle_refs[curr].count = 1;
+ handle_ref->count++;
+ curr++;
+ }
+ }
+
+ handle_refs[curr].handle = NULL;
+
+ /* Sort the handles by remote so duplicates canbe easily found. */
+ sort(handle_refs, ctx->handle_count, sizeof(*handle_refs), crs_handle_cmp, NULL);
+
+ /*
+ * Finally count references in each handle, allocate space for device
+ * specific ports, properties and fill the _CRS CSI2 descriptor
+ * originated data.
+ */
+ this = handle_refs;
+ this_count = this->count;
+ for (curr = 1; curr < ctx->handle_count + 1; curr++) {
+ /* Weed out duplicate receiver devices. */
+ if (this->handle == handle_refs[curr].handle) {
+ this_count += handle_refs[curr].count;
+ continue;
+ }
+
+ acpi_crs_csi2_alloc_fill_swnodes(this_count, this->handle);
+
+ this = &handle_refs[curr];
+ this_count = this->count;
+ }
+
+ kfree(handle_refs);
+}
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 280d12e0aa2f..ddf7701a57d0 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -2042,16 +2042,6 @@ struct acpi_postponed_handle {
acpi_handle handle;
};
-/**
- * struct acpi_scan_context - Context for scanning ACPI devices
- * @postponed_head: The list head of the postponed ACPI handles
- * @device: The first encountered device, typically the root of the scanned tree
- */
-struct acpi_scan_context {
- struct list_head postponed_head;
- struct acpi_device *device;
-};
-
/**
* acpi_bus_handle_postpone - Add an ACPI handle to a given postponed list
* @handle: The ACPI handle
@@ -2073,7 +2063,7 @@ static void acpi_bus_handle_postpone(acpi_handle handle,
list_add(&ph->list, head);
}
-static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep,
+static acpi_status acpi_bus_check_add(acpi_handle handle, bool first_pass,
struct acpi_scan_context *ctx)
{
struct acpi_device *device = acpi_fetch_acpi_dev(handle);
@@ -2091,8 +2081,11 @@ static acpi_status acpi_bus_check_add(acpi_handle handle, bool check_dep,
if (acpi_device_should_be_hidden(handle))
return AE_OK;
+ if (first_pass)
+ acpi_bus_scan_check_crs_csi2(handle, ctx);
+
/* Bail out if there are dependencies. */
- if (acpi_scan_check_dep(handle, check_dep) > 0) {
+ if (acpi_scan_check_dep(handle, first_pass) > 0) {
acpi_bus_handle_postpone(handle, &ctx->postponed_head);
return AE_CTRL_DEPTH;
}
@@ -2118,10 +2111,10 @@ 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;
@@ -2146,6 +2139,14 @@ static acpi_status acpi_bus_check_add_2(acpi_handle handle, u32 lvl_not_used,
return acpi_bus_check_add(handle, false, (struct acpi_scan_context *)ctx);
}
+static acpi_status acpi_bus_check_csi2(acpi_handle handle, u32 lvl_not_used,
+ void *ctx, void **unused)
+{
+ acpi_bus_scan_check_crs_csi2(handle, ctx);
+
+ return AE_OK;
+}
+
static void acpi_default_enumeration(struct acpi_device *device)
{
/*
@@ -2466,6 +2467,7 @@ int acpi_bus_scan(acpi_handle handle)
{
struct acpi_scan_context ctx = {
.postponed_head = LIST_HEAD_INIT(ctx.postponed_head),
+ .csi2.crs_csi2_head = LIST_HEAD_INIT(ctx.csi2.crs_csi2_head),
};
struct acpi_postponed_handle *ph, *tmp_ph;
int ret = 0;
@@ -2480,6 +2482,24 @@ int acpi_bus_scan(acpi_handle handle)
goto out_release;
}
+ /*
+ * Check _CRS CSI2 resource descriptors for devices that were not
+ * traversed during the previous pass.
+ */
+ list_for_each_entry_safe(ph, tmp_ph, &ctx.postponed_head, list) {
+ acpi_bus_check_csi2(ph->handle, 0, &ctx, NULL);
+ acpi_walk_namespace(ACPI_TYPE_DEVICE, ph->handle, ACPI_UINT32_MAX,
+ acpi_bus_check_csi2, NULL, (void *)&ctx,
+ NULL);
+ }
+
+ /*
+ * Construct software nodes out of _CRS CSI2 records and release the
+ * _CRS CSI2 records.
+ */
+ acpi_bus_scan_crs_csi2(&ctx.csi2);
+ acpi_bus_scan_crs_csi2_release(&ctx.csi2.crs_csi2_head);
+
acpi_bus_attach(ctx.device, (void *)true);
/*
@@ -2511,6 +2531,8 @@ int acpi_bus_scan(acpi_handle handle)
kfree(ph);
}
+ acpi_crs_csi2_swnodes_del_free();
+
return ret;
}
EXPORT_SYMBOL(acpi_bus_scan);
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 57acb895c038..e4e8faac9212 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -360,6 +360,17 @@ struct acpi_device_data {
struct acpi_gpio_mapping;
+struct acpi_device_software_node_port {
+ unsigned int port_nr;
+};
+
+struct acpi_device_software_nodes {
+ struct acpi_device_software_node_port *ports;
+ struct software_node *nodes;
+ const struct software_node **nodeptrs;
+ unsigned int num_ports;
+};
+
/* Device */
struct acpi_device {
u32 pld_crc;
--
2.30.2
