brcmfmac: expose device memory to devcoredump subsystem

Upon PSM watchdog event received from firmware the driver will obtain
a memory snapshot of the device and expose it to user-space through
the devcoredump framework. This will trigger a uevent.

Reviewed-by: Hante Meuleman <meuleman@broadcom.com>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
diff --git a/drivers/net/wireless/brcm80211/brcmfmac/debug.c b/drivers/net/wireless/brcm80211/brcmfmac/debug.c
index 2d6d005..1299dcc 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/debug.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/debug.c
@@ -16,15 +16,45 @@
 #include <linux/debugfs.h>
 #include <linux/netdevice.h>
 #include <linux/module.h>
+#include <linux/devcoredump.h>
 
 #include <brcmu_wifi.h>
 #include <brcmu_utils.h>
 #include "core.h"
 #include "bus.h"
+#include "fweh.h"
 #include "debug.h"
 
 static struct dentry *root_folder;
 
+static int brcmf_debug_create_memdump(struct brcmf_bus *bus, const void *data,
+				      size_t len)
+{
+	void *dump;
+	size_t ramsize;
+
+	ramsize = brcmf_bus_get_ramsize(bus);
+	if (ramsize) {
+		dump = vzalloc(len + ramsize);
+		if (!dump)
+			return -ENOMEM;
+		memcpy(dump, data, len);
+		brcmf_bus_get_memdump(bus, dump + len, ramsize);
+		dev_coredumpv(bus->dev, dump, len + ramsize, GFP_KERNEL);
+	}
+	return 0;
+}
+
+static int brcmf_debug_psm_watchdog_notify(struct brcmf_if *ifp,
+					   const struct brcmf_event_msg *evtmsg,
+					   void *data)
+{
+	brcmf_dbg(TRACE, "enter: idx=%d\n", ifp->bssidx);
+
+	return brcmf_debug_create_memdump(ifp->drvr->bus_if, data,
+					  evtmsg->datalen);
+}
+
 void brcmf_debugfs_init(void)
 {
 	root_folder = debugfs_create_dir(KBUILD_MODNAME, NULL);
@@ -41,7 +71,7 @@
 	root_folder = NULL;
 }
 
-int brcmf_debugfs_attach(struct brcmf_pub *drvr)
+int brcmf_debug_attach(struct brcmf_pub *drvr)
 {
 	struct device *dev = drvr->bus_if->dev;
 
@@ -49,12 +79,18 @@
 		return -ENODEV;
 
 	drvr->dbgfs_dir = debugfs_create_dir(dev_name(dev), root_folder);
+	if (IS_ERR(drvr->dbgfs_dir))
+		return PTR_ERR(drvr->dbgfs_dir);
 
-	return PTR_ERR_OR_ZERO(drvr->dbgfs_dir);
+
+	return brcmf_fweh_register(drvr, BRCMF_E_PSM_WATCHDOG,
+				   brcmf_debug_psm_watchdog_notify);
 }
 
-void brcmf_debugfs_detach(struct brcmf_pub *drvr)
+void brcmf_debug_detach(struct brcmf_pub *drvr)
 {
+	brcmf_fweh_unregister(drvr, BRCMF_E_PSM_WATCHDOG);
+
 	if (!IS_ERR_OR_NULL(drvr->dbgfs_dir))
 		debugfs_remove_recursive(drvr->dbgfs_dir);
 }