From b482b0d6f099e282c7499b5b1a3a69747bf4fa8b Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@hovoldconsulting.com>
Date: Sat, 23 Apr 2016 18:47:31 +0200
Subject: [PATCH] greybus: svc: implement interface mailbox event
Implement the new interface mailbox-event operation.
The event is sent by the SVC under certain conditions when an interface
updates its mailbox value. Specifically, this event will be used to
implement the new mode-switch functionality.
Upon reception the AP verifies that the interface is known and that the
mailbox has the expected MAILBOX_GREYBUS value. If so, the interface is
disabled before being re-enabled (re-enumerated).
Note that during mode-switch, the interface will typically already be in
a disabled state when the mailbox is written (with the ES3 bootrom being
the notable exception).
Signed-off-by: Johan Hovold <johan@hovoldconsulting.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
---
drivers/staging/greybus/greybus_protocols.h | 13 +++
drivers/staging/greybus/svc.c | 96 +++++++++++++++++++++
2 files changed, 109 insertions(+)
diff --git a/drivers/staging/greybus/greybus_protocols.h b/drivers/staging/greybus/greybus_protocols.h
index ece8c64ef13d2..bf3c132a32666 100644
--- a/drivers/staging/greybus/greybus_protocols.h
+++ b/drivers/staging/greybus/greybus_protocols.h
@@ -805,6 +805,7 @@ struct gb_spi_transfer_response {
#define GB_SVC_TYPE_MODULE_INSERTED 0x1f
#define GB_SVC_TYPE_MODULE_REMOVED 0x20
#define GB_SVC_TYPE_INTF_ACTIVATE 0x27
+#define GB_SVC_TYPE_INTF_MAILBOX_EVENT 0x29
/*
* SVC version request/response has the same payload as
@@ -1038,6 +1039,18 @@ struct gb_svc_intf_activate_response {
__u8 intf_type;
} __packed;
+#define GB_SVC_INTF_MAILBOX_NONE 0x00
+#define GB_SVC_INTF_MAILBOX_AP 0x01
+#define GB_SVC_INTF_MAILBOX_GREYBUS 0x02
+
+struct gb_svc_intf_mailbox_event_request {
+ __u8 intf_id;
+ __le16 result_code;
+ __le32 mailbox;
+} __packed;
+/* intf_mailbox_event response has no payload */
+
+
/* RAW */
/* Version of the Greybus raw protocol we support */
diff --git a/drivers/staging/greybus/svc.c b/drivers/staging/greybus/svc.c
index 9d90014ab2988..0a49698ce298f 100644
--- a/drivers/staging/greybus/svc.c
+++ b/drivers/staging/greybus/svc.c
@@ -695,6 +695,27 @@ static int gb_svc_hello(struct gb_operation *op)
return 0;
}
+static struct gb_interface *gb_svc_interface_lookup(struct gb_svc *svc,
+ u8 intf_id)
+{
+ struct gb_host_device *hd = svc->hd;
+ struct gb_module *module;
+ size_t num_interfaces;
+ u8 module_id;
+
+ list_for_each_entry(module, &hd->modules, hd_node) {
+ module_id = module->module_id;
+ num_interfaces = module->num_interfaces;
+
+ if (intf_id >= module_id &&
+ intf_id < module_id + num_interfaces) {
+ return module->interfaces[intf_id - module_id];
+ }
+ }
+
+ return NULL;
+}
+
static struct gb_module *gb_svc_module_lookup(struct gb_svc *svc, u8 module_id)
{
struct gb_host_device *hd = svc->hd;
@@ -874,6 +895,58 @@ static void gb_svc_process_module_removed(struct gb_operation *operation)
gb_module_put(module);
}
+static void gb_svc_process_intf_mailbox_event(struct gb_operation *operation)
+{
+ struct gb_svc_intf_mailbox_event_request *request;
+ struct gb_connection *connection = operation->connection;
+ struct gb_svc *svc = gb_connection_get_data(connection);
+ struct gb_interface *intf;
+ u8 intf_id;
+ u16 result_code;
+ u32 mailbox;
+
+ /* The request message size has already been verified. */
+ request = operation->request->payload;
+ intf_id = request->intf_id;
+ result_code = le16_to_cpu(request->result_code);
+ mailbox = le32_to_cpu(request->mailbox);
+
+ dev_dbg(&svc->dev, "%s - id = %u, result = 0x%04x, mailbox = 0x%08x\n",
+ __func__, intf_id, result_code, mailbox);
+
+ intf = gb_svc_interface_lookup(svc, intf_id);
+ if (!intf) {
+ dev_warn(&svc->dev, "unexpected mailbox event %u\n", intf_id);
+ return;
+ }
+
+ if (result_code) {
+ dev_warn(&svc->dev,
+ "mailbox event %u with UniPro error: 0x%04x\n",
+ intf_id, result_code);
+ goto err_disable_interface;
+ }
+
+ if (mailbox != GB_SVC_INTF_MAILBOX_GREYBUS) {
+ dev_warn(&svc->dev,
+ "mailbox event %u with unexected value: 0x%08x\n",
+ intf_id, mailbox);
+ goto err_disable_interface;
+ }
+
+ dev_info(&svc->dev, "mode switch detected on interface %u\n", intf_id);
+
+ gb_svc_intf_reenable(svc, intf);
+
+ return;
+
+err_disable_interface:
+ mutex_lock(&intf->mutex);
+ gb_interface_disable(intf);
+ gb_interface_deactivate(intf);
+ mutex_unlock(&intf->mutex);
+}
+
static void gb_svc_process_deferred_request(struct work_struct *work)
{
struct gb_svc_deferred_request *dr;
@@ -899,6 +972,9 @@ static void gb_svc_process_deferred_request(struct work_struct *work)
case GB_SVC_TYPE_MODULE_REMOVED:
gb_svc_process_module_removed(operation);
break;
+ case GB_SVC_TYPE_INTF_MAILBOX_EVENT:
+ gb_svc_process_intf_mailbox_event(operation);
+ break;
default:
dev_err(&svc->dev, "bad deferred request type: 0x%02x\n", type);
}
@@ -1077,6 +1153,24 @@ static int gb_svc_module_removed_recv(struct gb_operation *op)
return gb_svc_queue_deferred_request(op);
}
+static int gb_svc_intf_mailbox_event_recv(struct gb_operation *op)
+{
+ struct gb_svc *svc = gb_connection_get_data(op->connection);
+ struct gb_svc_intf_mailbox_event_request *request;
+
+ if (op->request->payload_size < sizeof(*request)) {
+ dev_warn(&svc->dev, "short mailbox request received (%zu < %zu)\n",
+ op->request->payload_size, sizeof(*request));
+ return -EINVAL;
+ }
+
+ request = op->request->payload;
+
+ dev_dbg(&svc->dev, "%s - id = %u\n", __func__, request->intf_id);
+
+ return gb_svc_queue_deferred_request(op);
+}
+
static int gb_svc_request_handler(struct gb_operation *op)
{
struct gb_connection *connection = op->connection;
@@ -1138,6 +1232,8 @@ static int gb_svc_request_handler(struct gb_operation *op)
return gb_svc_module_inserted_recv(op);
case GB_SVC_TYPE_MODULE_REMOVED:
return gb_svc_module_removed_recv(op);
+ case GB_SVC_TYPE_INTF_MAILBOX_EVENT:
+ return gb_svc_intf_mailbox_event_recv(op);
default:
dev_warn(&svc->dev, "unsupported request 0x%02x\n", type);
return -EINVAL;
--
2.30.2