From: Linus Walleij <linus.walleij@linaro.org>

Date: Sun, 20 Mar 2022 23:27:49 +0100

Subject: Bluetooth: btbcm: Support per-board firmware variants

Patch-mainline: v5.19-rc1

Git-commit: 63fac3343b99e6726830bb40028fbe23c864eafe

References: jsc#PED-1407

There are provedly different firmware variants for the different

phones using some of these chips. These were extracted from a few

Samsung phones:

37446 BCM4334B0.samsung,codina-tmo.hcd

37366 BCM4334B0.samsung,golden.hcd

37403 BCM4334B0.samsung,kyle.hcd

37366 BCM4334B0.samsung,skomer.hcd

This patch supports the above naming schedule with inserting

[.board_name] between the firmware name and ".hcd". This scheme

is the same as used by the companion BRCM wireless chips

as can be seen in

drivers/net/wireless/broadcom/brcm80211/brcmfmac/firmware.c

or just by looking at the firmwares in linux-firmware/brcm.

Currently we only support board variants using the device

tree compatible string as board type, but other schemes are

possible.

This makes it possible to successfully load a few unique

firmware variants for some Samsung phones.

Cc: phone-devel@vger.kernel.org

Cc: Markuss Broks <markuss.broks@gmail.com>

Cc: Stephan Gerhold <stephan@gerhold.net>

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

Acked-by: Lee, Chun-Yi <jlee@suse.com>

---

 drivers/bluetooth/btbcm.c |   52 +++++++++++++++++++++++++++++++++++++++++++++-

 1 file changed, 51 insertions(+), 1 deletion(-)

--- a/drivers/bluetooth/btbcm.c

+++ b/drivers/bluetooth/btbcm.c

@@ -9,6 +9,7 @@

 #include <linux/module.h>

 #include <linux/firmware.h>

 #include <linux/dmi.h>

+#include <linux/of.h>

 #include <asm/unaligned.h>

 #include <net/bluetooth/bluetooth.h>

@@ -29,7 +30,7 @@

 #define BDADDR_BCM43341B (&(bdaddr_t) {{0xac, 0x1f, 0x00, 0x1b, 0x34, 0x43}})

 #define BCM_FW_NAME_LEN			64

-#define BCM_FW_NAME_COUNT_MAX		2

+#define BCM_FW_NAME_COUNT_MAX		4

 /* For kmalloc-ing the fw-name array instead of putting it on the stack */

 typedef char bcm_fw_name[BCM_FW_NAME_LEN];

@@ -476,6 +477,42 @@ static const struct bcm_subver_table bcm

 	{ }

 };

+/*

+ * This currently only looks up the device tree board appendix,

+ * but can be expanded to other mechanisms.

+ */

+static const char *btbcm_get_board_name(struct device *dev)

+{

+#ifdef CONFIG_OF

+	struct device_node *root;

+	char *board_type;

+	const char *tmp;

+	int len;

+	int i;

+

+	root = of_find_node_by_path("/");

+	if (!root)

+		return NULL;

+

+	if (of_property_read_string_index(root, "compatible", 0, &tmp))

+		return NULL;

+

+	/* get rid of any '/' in the compatible string */

+	len = strlen(tmp) + 1;

+	board_type = devm_kzalloc(dev, len, GFP_KERNEL);

+	strscpy(board_type, tmp, len);

+	for (i = 0; i < board_type[i]; i++) {

+		if (board_type[i] == '/')

+			board_type[i] = '-';

+	}

+	of_node_put(root);

+

+	return board_type;

+#else

+	return NULL;

+#endif

+}

+

 int btbcm_initialize(struct hci_dev *hdev, bool *fw_load_done)

 {

 	u16 subver, rev, pid, vid;

@@ -483,12 +520,15 @@ int btbcm_initialize(struct hci_dev *hde

 	struct hci_rp_read_local_version *ver;

 	const struct bcm_subver_table *bcm_subver_table;

 	const char *hw_name = NULL;

+	const char *board_name;

 	char postfix[16] = "";

 	int fw_name_count = 0;

 	bcm_fw_name *fw_name;

 	const struct firmware *fw;

 	int i, err;

+	board_name = btbcm_get_board_name(&hdev->dev);

+

 	/* Reset */

 	err = btbcm_reset(hdev);

 	if (err)

@@ -549,11 +589,21 @@ int btbcm_initialize(struct hci_dev *hde

 		return -ENOMEM;

 	if (hw_name) {

+		if (board_name) {

+			snprintf(fw_name[fw_name_count], BCM_FW_NAME_LEN,

+				 "brcm/%s%s.%s.hcd", hw_name, postfix, board_name);

+			fw_name_count++;

+		}

 		snprintf(fw_name[fw_name_count], BCM_FW_NAME_LEN,

 			 "brcm/%s%s.hcd", hw_name, postfix);

 		fw_name_count++;

 	}

+	if (board_name) {

+		snprintf(fw_name[fw_name_count], BCM_FW_NAME_LEN,

+			 "brcm/BCM%s.%s.hcd", postfix, board_name);

+		fw_name_count++;

+	}

 	snprintf(fw_name[fw_name_count], BCM_FW_NAME_LEN,

 		 "brcm/BCM%s.hcd", postfix);

 	fw_name_count++;