wifi: brcmfmac: add support for vendor-specific firmware api

The driver is being used by multiple vendors who develop the firmware
api independently. So far the firmware api as used by the driver has
not diverged (yet). This change adds framework for supporting multiple
firmware apis. The vendor-specific support code has to provide a number
of callback operations. Right now it is only attach and detach callbacks
so no real functionality as the api is still common. This code only
adds WCC variant anyway, which is selected for all devices right now.
The vendor-specific part will be built in a separate module when the
driver is configured to be built as a module through Kconfig, ie. when
CONFIG_BRCMFMAC=m.

Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com>
Reviewed-by: Franky Lin <franky.lin@broadcom.com>
Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/20221129135446.151065-4-arend.vanspriel@broadcom.com

1 files changed, 190 insertions, 0 deletions

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwvid.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwvid.c
new file mode 100644
index 000000000000..f5cbb09b1c83
--- /dev/null
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/fwvid.c
@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: ISC
+/*
+ * Copyright (c) 2022 Broadcom Corporation
+ */
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/kmod.h>
+#include <linux/list.h>
+#include <linux/completion.h>
+#include <linux/mutex.h>
+#include <linux/printk.h>
+#include <linux/jiffies.h>
+#include <linux/workqueue.h>
+
+#include "core.h"
+#include "bus.h"
+#include "debug.h"
+#include "fwvid.h"
+
+#include "wcc/vops.h"
+
+struct brcmf_fwvid_entry {
+	const char *name;
+	const struct brcmf_fwvid_ops *vops;
+	struct list_head drvr_list;
+#if IS_MODULE(CONFIG_BRCMFMAC)
+	struct module *vmod;
+	struct completion reg_done;
+#endif
+};
+
+static DEFINE_MUTEX(fwvid_list_lock);
+
+#if IS_MODULE(CONFIG_BRCMFMAC)
+#define FWVID_ENTRY_INIT(_vid, _name) \
+	[BRCMF_FWVENDOR_ ## _vid] = { \
+		.name = #_name, \
+		.reg_done = COMPLETION_INITIALIZER(fwvid_list[BRCMF_FWVENDOR_ ## _vid].reg_done), \
+		.drvr_list = LIST_HEAD_INIT(fwvid_list[BRCMF_FWVENDOR_ ## _vid].drvr_list), \
+	}
+#else
+#define FWVID_ENTRY_INIT(_vid, _name) \
+	[BRCMF_FWVENDOR_ ## _vid] = { \
+		.name = #_name, \
+		.drvr_list = LIST_HEAD_INIT(fwvid_list[BRCMF_FWVENDOR_ ## _vid].drvr_list), \
+		.vops = _vid ## _VOPS \
+	}
+#endif /* IS_MODULE(CONFIG_BRCMFMAC) */
+
+static struct brcmf_fwvid_entry fwvid_list[BRCMF_FWVENDOR_NUM] = {
+	FWVID_ENTRY_INIT(WCC, wcc),
+};
+
+#if IS_MODULE(CONFIG_BRCMFMAC)
+static int brcmf_fwvid_request_module(enum brcmf_fwvendor fwvid)
+{
+	int ret;
+
+	if (!fwvid_list[fwvid].vmod) {
+		struct completion *reg_done = &fwvid_list[fwvid].reg_done;
+
+		mutex_unlock(&fwvid_list_lock);
+
+		ret = request_module("brcmfmac-%s", fwvid_list[fwvid].name);
+		if (ret)
+			goto fail;
+
+		ret = wait_for_completion_interruptible(reg_done);
+		if (ret)
+			goto fail;
+
+		mutex_lock(&fwvid_list_lock);
+	}
+	return 0;
+
+fail:
+	brcmf_err("mod=%s: failed %d\n", fwvid_list[fwvid].name, ret);
+	return ret;
+}
+
+int brcmf_fwvid_register_vendor(enum brcmf_fwvendor fwvid, struct module *vmod,
+				const struct brcmf_fwvid_ops *vops)
+{
+	if (fwvid >= BRCMF_FWVENDOR_NUM)
+		return -ERANGE;
+
+	if (WARN_ON(!vmod) || WARN_ON(!vops) ||
+	    WARN_ON(!vops->attach) || WARN_ON(!vops->detach))
+		return -EINVAL;
+
+	if (WARN_ON(fwvid_list[fwvid].vmod))
+		return -EEXIST;
+
+	brcmf_dbg(TRACE, "mod=%s: enter\n", fwvid_list[fwvid].name);
+
+	mutex_lock(&fwvid_list_lock);
+
+	fwvid_list[fwvid].vmod = vmod;
+	fwvid_list[fwvid].vops = vops;
+
+	mutex_unlock(&fwvid_list_lock);
+
+	complete_all(&fwvid_list[fwvid].reg_done);
+
+	return 0;
+}
+EXPORT_SYMBOL(brcmf_fwvid_register_vendor);
+
+int brcmf_fwvid_unregister_vendor(enum brcmf_fwvendor fwvid, struct module *mod)
+{
+	struct brcmf_bus *bus, *tmp;
+
+	if (fwvid >= BRCMF_FWVENDOR_NUM)
+		return -ERANGE;
+
+	if (WARN_ON(fwvid_list[fwvid].vmod != mod))
+		return -ENOENT;
+
+	mutex_lock(&fwvid_list_lock);
+
+	list_for_each_entry_safe(bus, tmp, &fwvid_list[fwvid].drvr_list, list) {
+		mutex_unlock(&fwvid_list_lock);
+
+		brcmf_dbg(INFO, "mod=%s: removing %s\n", fwvid_list[fwvid].name,
+			  dev_name(bus->dev));
+		brcmf_bus_remove(bus);
+
+		mutex_lock(&fwvid_list_lock);
+	}
+
+	fwvid_list[fwvid].vmod = NULL;
+	fwvid_list[fwvid].vops = NULL;
+	reinit_completion(&fwvid_list[fwvid].reg_done);
+
+	brcmf_dbg(TRACE, "mod=%s: exit\n", fwvid_list[fwvid].name);
+	mutex_unlock(&fwvid_list_lock);
+
+	return 0;
+}
+EXPORT_SYMBOL(brcmf_fwvid_unregister_vendor);
+#else
+static inline int brcmf_fwvid_request_module(enum brcmf_fwvendor fwvid)
+{
+	return 0;
+}
+#endif
+
+int brcmf_fwvid_attach_ops(struct brcmf_pub *drvr)
+{
+	enum brcmf_fwvendor fwvid = drvr->bus_if->fwvid;
+	int ret;
+
+	if (fwvid >= ARRAY_SIZE(fwvid_list))
+		return -ERANGE;
+
+	brcmf_dbg(TRACE, "mod=%s: enter: dev %s\n", fwvid_list[fwvid].name,
+		  dev_name(drvr->bus_if->dev));
+
+	mutex_lock(&fwvid_list_lock);
+
+	ret = brcmf_fwvid_request_module(fwvid);
+	if (ret)
+		return ret;
+
+	drvr->vops = fwvid_list[fwvid].vops;
+	list_add(&drvr->bus_if->list, &fwvid_list[fwvid].drvr_list);
+
+	mutex_unlock(&fwvid_list_lock);
+
+	return ret;
+}
+
+void brcmf_fwvid_detach_ops(struct brcmf_pub *drvr)
+{
+	enum brcmf_fwvendor fwvid = drvr->bus_if->fwvid;
+
+	if (fwvid >= ARRAY_SIZE(fwvid_list))
+		return;
+
+	brcmf_dbg(TRACE, "mod=%s: enter: dev %s\n", fwvid_list[fwvid].name,
+		  dev_name(drvr->bus_if->dev));
+
+	mutex_lock(&fwvid_list_lock);
+
+	drvr->vops = NULL;
+	list_del(&drvr->bus_if->list);
+
+	mutex_unlock(&fwvid_list_lock);
+}