[PATCH v12 1/3] Bluetooth: hci_uart: add prepare callbacks to hci_uart_proto structure.

[PATCH v12 1/3] Bluetooth: hci_uart: add prepare callbacks to hci_uart_proto structure.

[Amitkumar Karwar]

From: Ganapathi Bhat <gbhat-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>

The new callback is used to prepare the device before HCI becomes
ready. One can use this to download firmware if the download process
doesn't use HCI commands. Also recv_for_prepare callback is
introduced for receiving data from devices during prepare phase.

Signed-off-by: Ganapathi Bhat <gbhat-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
Signed-off-by: Amitkumar Karwar <akarwar-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
---
 drivers/bluetooth/hci_ldisc.c | 11 ++++++++++-
 drivers/bluetooth/hci_uart.h  |  3 +++
 2 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index dda9739..d7184dc 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -551,8 +551,11 @@ static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
 	if (!hu || tty != hu->tty)
 		return;
 
-	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags))
+	if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) {
+		if (hu->proto->recv_for_prepare)
+			hu->proto->recv_for_prepare(hu, data, count);
 		return;
+	}
 
 	/* It does not need a lock here as it is already protected by a mutex in
 	 * tty caller
@@ -639,6 +642,12 @@ static int hci_uart_set_proto(struct hci_uart *hu, int id)
 		return err;
 
 	hu->proto = p;
+	if (p->prepare) {
+		err = p->prepare(hu);
+		if (err)
+			return err;
+	}
+
 	set_bit(HCI_UART_PROTO_READY, &hu->flags);
 
 	err = hci_uart_register_dev(hu);
diff --git a/drivers/bluetooth/hci_uart.h b/drivers/bluetooth/hci_uart.h
index 839bad1..17ba3b4 100644
--- a/drivers/bluetooth/hci_uart.h
+++ b/drivers/bluetooth/hci_uart.h
@@ -67,8 +67,11 @@ struct hci_uart_proto {
 	int (*close)(struct hci_uart *hu);
 	int (*flush)(struct hci_uart *hu);
 	int (*setup)(struct hci_uart *hu);
+	int (*prepare)(struct hci_uart *hu);
 	int (*set_baudrate)(struct hci_uart *hu, unsigned int speed);
 	int (*recv)(struct hci_uart *hu, const void *data, int len);
+	int (*recv_for_prepare)(struct hci_uart *hu, const void *data,
+				int len);
 	int (*enqueue)(struct hci_uart *hu, struct sk_buff *skb);
 	struct sk_buff *(*dequeue)(struct hci_uart *hu);
 };
-- 
1.8.1.4

[PATCH v12 2/3] Bluetooth: hci_uart: check if hdev is present before using it

[Amitkumar Karwar]

From: Ganapathi Bhat <gbhat-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>

The hdev struct might not have initialized in protocol receive handler.
This patch adds necessary checks.

Signed-off-by: Ganapathi Bhat <gbhat-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
Signed-off-by: Amitkumar Karwar <akarwar-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
---
 drivers/bluetooth/hci_ldisc.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index d7184dc..2c88586 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -154,7 +154,9 @@ restart:
 
 		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
 		len = tty->ops->write(tty, skb->data, skb->len);
-		hdev->stat.byte_tx += len;
+
+		if (hdev)
+			hdev->stat.byte_tx += len;
 
 		skb_pull(skb, len);
 		if (skb->len) {
@@ -349,7 +351,7 @@ void hci_uart_set_baudrate(struct hci_uart *hu, unsigned int speed)
 	/* tty_set_termios() return not checked as it is always 0 */
 	tty_set_termios(tty, &ktermios);
 
-	BT_DBG("%s: New tty speeds: %d/%d", hu->hdev->name,
+	BT_DBG("%s: New tty speeds: %d/%d", hu->hdev ? hu->hdev->name : "",
 	       tty->termios.c_ispeed, tty->termios.c_ospeed);
 }
 
-- 
1.8.1.4

[PATCH v12 3/3] Bluetooth: hci_uart: Support firmware download for Marvell

[Amitkumar Karwar]

From: Ganapathi Bhat <gbhat-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>

This patch implement firmware download feature for
Marvell Bluetooth devices. If firmware is already
downloaded, it will skip downloading.

Signed-off-by: Ganapathi Bhat <gbhat-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
Signed-off-by: Amitkumar Karwar <akarwar-eYqpPyKDWXRBDgjK7y7TUQ@public.gmane.org>
Tested-by: Jeffy Chen <jeffy.chen-TNX95d0MmH7DzftRWevZcw@public.gmane.org>
---
v2: Fixed compilation warning reported by kbuild test robot
v3: Addressed review comments from Marcel Holtmann
    a) Removed vendor specific code from hci_ldisc.c
    b) Get rid of static forward declaration
    c) Removed unnecessary heavy nesting
    d) Git rid of module parameter and global variables
    e) Add logic to pick right firmware image
v4: Addresses review comments from Alan
    a) Use existing kernel helper APIs instead of writing own.
    b) Replace mdelay() with msleep()
v5: Addresses review comments from Loic Poulain
    a) Use bt_dev_err/warn/dbg helpers insted of BT_ERR/WARN/DBG
    b) Used static functions where required and removed forward delcarations
    c) Edited comments for the function hci_uart_recv_data
    d) Made HCI_UART_DNLD_FW flag a part of driver private data
v6: Addresses review comments from Loic Poulain
    a) Used skb instead of array to store firmware data during download
    b) Used hci_uart_tx_wakeup and enqueued packets instead of tty write
    c) Used GFP_KERNEL instead of GFP_ATOMIC
v7: Edited Kconfig to add dependency for BT_HCIUART_H4. The change resolves
    errors reported by kbuild test robot.
v8: Addressed review comments from Marcel Holtmann
    a) Removed unnecessary memory allocation failure messages
    b) Get rid of btmrvl.h header file and add definitions in hci_mrvl.c file
v9: Addressed review comments from Marcel Holtmann
    a) Moved firmware download code from setup to prepare handler.
    b) Change messages from bt_dev_*->BT_*, as hdev isn't available during firmware
     download.
v10: Addressed review comments from Marcel Holtmann
    a) Added new callback recv_for_prepare to receive data from device
     during prepare phase
    b) Avoided using private flags (HCI_UART_DNLD_FW) as new receive callback is
     added for the same purpose
    c) Used kernel API to handle unaligned data
    d) Moved mrvl_set_baud functionality inside setup callback
v11: Write data through ldisc in mrvl_send_ack() instead of directly calling
    write method(One Thousand Gnomes).
v12: a) Check for buffer length before copying to skb (Loic Poulain)
     b) Rearrange skb memory allocation check
---
 drivers/bluetooth/Kconfig     |  11 +
 drivers/bluetooth/Makefile    |   1 +
 drivers/bluetooth/hci_ldisc.c |   6 +
 drivers/bluetooth/hci_mrvl.c  | 545 ++++++++++++++++++++++++++++++++++++++++++
 drivers/bluetooth/hci_uart.h  |   8 +-
 5 files changed, 570 insertions(+), 1 deletion(-)
 create mode 100644 drivers/bluetooth/hci_mrvl.c

diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
index cf50fd2..daafd0c 100644
--- a/drivers/bluetooth/Kconfig
+++ b/drivers/bluetooth/Kconfig
@@ -180,6 +180,17 @@ config BT_HCIUART_AG6XX
 
 	  Say Y here to compile support for Intel AG6XX protocol.
 
+config BT_HCIUART_MRVL
+	bool "Marvell protocol support"
+	depends on BT_HCIUART
+	select BT_HCIUART_H4
+	help
+	  Marvell is serial protocol for communication between Bluetooth
+	  device and host. This protocol is required for most Marvell Bluetooth
+	  devices with UART interface.
+
+	  Say Y here to compile support for HCI MRVL protocol.
+
 config BT_HCIBCM203X
 	tristate "HCI BCM203x USB driver"
 	depends on USB
diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile
index 9c18939..364dbb6 100644
--- a/drivers/bluetooth/Makefile
+++ b/drivers/bluetooth/Makefile
@@ -37,6 +37,7 @@ hci_uart-$(CONFIG_BT_HCIUART_INTEL)	+= hci_intel.o
 hci_uart-$(CONFIG_BT_HCIUART_BCM)	+= hci_bcm.o
 hci_uart-$(CONFIG_BT_HCIUART_QCA)	+= hci_qca.o
 hci_uart-$(CONFIG_BT_HCIUART_AG6XX)	+= hci_ag6xx.o
+hci_uart-$(CONFIG_BT_HCIUART_MRVL)	+= hci_mrvl.o
 hci_uart-objs				:= $(hci_uart-y)
 
 ccflags-y += -D__CHECK_ENDIAN__
diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index 2c88586..ded13d3 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -821,6 +821,9 @@ static int __init hci_uart_init(void)
 #ifdef CONFIG_BT_HCIUART_AG6XX
 	ag6xx_init();
 #endif
+#ifdef CONFIG_BT_HCIUART_MRVL
+	mrvl_init();
+#endif
 
 	return 0;
 }
@@ -856,6 +859,9 @@ static void __exit hci_uart_exit(void)
 #ifdef CONFIG_BT_HCIUART_AG6XX
 	ag6xx_deinit();
 #endif
+#ifdef CONFIG_BT_HCIUART_MRVL
+	mrvl_deinit();
+#endif
 
 	/* Release tty registration of line discipline */
 	err = tty_unregister_ldisc(N_HCI);
diff --git a/drivers/bluetooth/hci_mrvl.c b/drivers/bluetooth/hci_mrvl.c
new file mode 100644
index 0000000..c993c1b
--- /dev/null
+++ b/drivers/bluetooth/hci_mrvl.c
@@ -0,0 +1,545 @@
+/* Bluetooth HCI UART driver for Marvell devices
+ *
+ * Copyright (C) 2016, Marvell International Ltd.
+ *
+ *  Acknowledgements:
+ *  This file is based on hci_h4.c, which was written
+ *  by Maxim Krasnyansky and Marcel Holtmann.
+ *
+ * This software file (the "File") is distributed by Marvell International
+ * Ltd. under the terms of the GNU General Public License Version 2, June 1991
+ * (the "License").  You may use, redistribute and/or modify this File in
+ * accordance with the terms and conditions of the License, a copy of which
+ * is available on the worldwide web at
+ * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
+ *
+ * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
+ * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
+ * this warranty disclaimer.
+ */
+
+#include <linux/firmware.h>
+#include <linux/tty.h>
+#include <asm/unaligned.h>
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include "hci_uart.h"
+
+struct fw_data {
+	wait_queue_head_t init_wait_q;
+	u8 wait_fw;
+	int next_len;
+	u8 five_bytes[5];
+	u8 next_index;
+	u8 last_ack;
+	u8 expected_ack;
+	struct ktermios old_termios;
+	u8 chip_id;
+	u8 chip_rev;
+	struct sk_buff *skb;
+};
+
+#define MRVL_HELPER_NAME	"mrvl/helper_uart_3000000.bin"
+#define MRVL_8997_CHIP_ID	0x50
+#define MRVL_8997_FW_NAME	"mrvl/uart8997_bt.bin"
+#define MRVL_MAX_FW_BLOCK_SIZE	1024
+#define MRVL_MAX_RETRY_SEND	12
+#define MRVL_DNLD_DELAY		100
+#define MRVL_ACK		0x5A
+#define MRVL_NAK		0xBF
+#define MRVL_HDR_REQ_FW		0xA5
+#define MRVL_HDR_CHIP_VER	0xAA
+#define MRVL_HCI_OP_SET_BAUD	0xFC09
+#define MRVL_FW_HDR_LEN		5
+#define MRVL_WAIT_TIMEOUT	msecs_to_jiffies(12000)
+
+struct mrvl_data {
+	struct sk_buff *rx_skb;
+	struct sk_buff_head txq;
+	struct fw_data *fwdata;
+};
+
+static int get_cts(struct hci_uart *hu)
+{
+	struct tty_struct *tty = hu->tty;
+	u32 state =  tty->ops->tiocmget(tty);
+
+	if (state & TIOCM_CTS) {
+		bt_dev_dbg(hu->hdev, "CTS is low");
+		return 1;
+	}
+	bt_dev_dbg(hu->hdev, "CTS is high");
+
+	return 0;
+}
+
+/* Initialize protocol */
+static int mrvl_open(struct hci_uart *hu)
+{
+	struct mrvl_data *mrvl;
+
+	bt_dev_dbg(hu->hdev, "hu %p", hu);
+
+	mrvl = kzalloc(sizeof(*mrvl), GFP_KERNEL);
+	if (!mrvl)
+		return -ENOMEM;
+
+	skb_queue_head_init(&mrvl->txq);
+	hu->priv = mrvl;
+
+	return 0;
+}
+
+/* Flush protocol data */
+static int mrvl_flush(struct hci_uart *hu)
+{
+	struct mrvl_data *mrvl = hu->priv;
+
+	bt_dev_dbg(hu->hdev, "hu %p", hu);
+
+	skb_queue_purge(&mrvl->txq);
+
+	return 0;
+}
+
+/* Close protocol */
+static int mrvl_close(struct hci_uart *hu)
+{
+	struct mrvl_data *mrvl = hu->priv;
+
+	bt_dev_dbg(hu->hdev, "hu %p", hu);
+
+	skb_queue_purge(&mrvl->txq);
+	kfree_skb(mrvl->rx_skb);
+	hu->priv = NULL;
+	kfree(mrvl);
+
+	return 0;
+}
+
+/* Enqueue frame for transmittion (padding, crc, etc) */
+static int mrvl_enqueue(struct hci_uart *hu, struct sk_buff *skb)
+{
+	struct mrvl_data *mrvl = hu->priv;
+
+	bt_dev_dbg(hu->hdev, "hu %p skb %p", hu, skb);
+
+	/* Prepend skb with frame type */
+	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
+	skb_queue_tail(&mrvl->txq, skb);
+
+	return 0;
+}
+
+static const struct h4_recv_pkt mrvl_recv_pkts[] = {
+	{ H4_RECV_ACL,   .recv = hci_recv_frame },
+	{ H4_RECV_SCO,   .recv = hci_recv_frame },
+	{ H4_RECV_EVENT, .recv = hci_recv_frame },
+};
+
+/* Send ACK/NAK to the device */
+static void mrvl_send_ack(struct hci_uart *hu, unsigned char ack)
+{
+	struct mrvl_data *mrvl = hu->priv;
+	struct sk_buff *skb = NULL;
+
+	skb = bt_skb_alloc(sizeof(ack), GFP_KERNEL);
+	if (!skb)
+		return;
+
+	memcpy(skb->data, &ack, sizeof(ack));
+	skb_put(skb, sizeof(ack));
+	skb_queue_head(&mrvl->txq, skb);
+	hci_uart_tx_wakeup(hu);
+}
+
+/* Validate the feedback data from device */
+static void mrvl_pkt_complete(struct hci_uart *hu, struct sk_buff *skb)
+{
+	struct mrvl_data *mrvl = hu->priv;
+	struct fw_data *fw_data = mrvl->fwdata;
+	u16 lhs, rhs;
+
+	lhs = get_unaligned_le16(skb->data + 1);
+	rhs = get_unaligned_le16(skb->data + 3);
+	if ((lhs ^ rhs) == 0xffff) {
+		mrvl_send_ack(hu, MRVL_ACK);
+		fw_data->wait_fw = 1;
+		fw_data->next_len = lhs;
+		/* Firmware download is done, send the last ack */
+		if (!lhs)
+			fw_data->last_ack = 1;
+
+		if (fw_data->expected_ack == MRVL_HDR_CHIP_VER) {
+			fw_data->chip_id = skb->data[1];
+			fw_data->chip_rev = skb->data[2];
+		}
+		wake_up_interruptible(&fw_data->init_wait_q);
+	} else {
+		mrvl_send_ack(hu, MRVL_NAK);
+	}
+}
+
+/* This function receives data from the uart device during firmware download.
+ * Driver expects 5 bytes of data as per the protocal in the below format:
+ * <HEADER><BYTE_1><BYTE_2><BYTE_3><BYTE_4>
+ * BYTE_3 and BYTE_4 are compliment of BYTE_1 an BYTE_2. Data can come in chunks
+ * of any length. If length received is < 5, accumulate the data in an array,
+ * until we have a sequence of 5 bytes, starting with the expected HEADER. If
+ * the length received is > 5  bytes, then get the first 5 bytes, starting with
+ * the HEADER and process the same, ignoring the rest of the bytes as per the
+ * protocal.
+ */
+static struct sk_buff *mrvl_process_fw_data(struct hci_uart *hu,
+					    struct sk_buff *skb,
+					    u8 *buf, int count)
+{
+	struct mrvl_data *mrvl = hu->priv;
+	struct fw_data *fw_data = mrvl->fwdata;
+	int i = 0, len;
+
+	if (!skb) {
+		while ((i < count) && buf[i] != fw_data->expected_ack)
+			i++;
+		if (i == count)
+			return ERR_PTR(-EILSEQ);
+
+		skb = bt_skb_alloc(MRVL_FW_HDR_LEN, GFP_KERNEL);
+		if (!skb)
+			return ERR_PTR(-ENOMEM);
+	}
+
+	len = count - i;
+	if ((len + skb->len) > MRVL_FW_HDR_LEN)
+		return ERR_PTR(-EILSEQ);
+
+	memcpy(skb_put(skb, len), &buf[i], len);
+
+	if (skb->len == MRVL_FW_HDR_LEN) {
+		mrvl_pkt_complete(hu, skb);
+		kfree_skb(skb);
+		skb = NULL;
+	}
+
+	return skb;
+}
+
+/* Receive firmware feedback data */
+static int mrvl_recv_for_prepare(struct hci_uart *hu, const void *data,
+				 int count)
+{
+	struct mrvl_data *mrvl = hu->priv;
+
+	mrvl->fwdata->skb = mrvl_process_fw_data(hu, mrvl->fwdata->skb,
+						 (u8 *)data, count);
+	if (IS_ERR(mrvl->fwdata->skb)) {
+		int err = PTR_ERR(mrvl->fwdata->skb);
+
+		bt_dev_err(hu->hdev,
+			   "Receive firmware data failed (%d)", err);
+		mrvl->fwdata->skb = NULL;
+		return err;
+	}
+
+	return 0;
+}
+
+/* Receive data */
+static int mrvl_recv(struct hci_uart *hu, const void *data, int count)
+{
+	struct mrvl_data *mrvl = hu->priv;
+
+	if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
+		return -EUNATCH;
+
+	mrvl->rx_skb = h4_recv_buf(hu->hdev, mrvl->rx_skb, data, count,
+				   mrvl_recv_pkts, ARRAY_SIZE(mrvl_recv_pkts));
+	if (IS_ERR(mrvl->rx_skb)) {
+		int err = PTR_ERR(mrvl->rx_skb);
+
+		bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
+		mrvl->rx_skb = NULL;
+		return err;
+	}
+
+	return count;
+}
+
+static struct sk_buff *mrvl_dequeue(struct hci_uart *hu)
+{
+	struct mrvl_data *mrvl = hu->priv;
+
+	return skb_dequeue(&mrvl->txq);
+}
+
+static int mrvl_init_fw_data(struct hci_uart *hu)
+{
+	struct fw_data *fwdata;
+	struct mrvl_data *mrvl = hu->priv;
+
+	fwdata = kzalloc(sizeof(*fwdata), GFP_KERNEL);
+	if (!fwdata)
+		return -ENOMEM;
+
+	mrvl->fwdata = fwdata;
+	init_waitqueue_head(&fwdata->init_wait_q);
+
+	return 0;
+}
+
+/* Wait for the header from device */
+static int mrvl_wait_for_hdr(struct hci_uart *hu, u8 header)
+{
+	struct mrvl_data *mrvl = hu->priv;
+	struct fw_data *fw_data = mrvl->fwdata;
+
+	fw_data->expected_ack = header;
+	fw_data->wait_fw = 0;
+
+	if (!wait_event_interruptible_timeout(fw_data->init_wait_q,
+					      fw_data->wait_fw,
+					      MRVL_WAIT_TIMEOUT)) {
+		BT_ERR("TIMEOUT, waiting for:0x%x", fw_data->expected_ack);
+		return -1;
+	}
+
+	return 0;
+}
+
+/* Send bytes to device */
+static int mrvl_send_data(struct hci_uart *hu, struct sk_buff *skb)
+{
+	struct mrvl_data *mrvl = hu->priv;
+
+	skb_queue_head(&mrvl->txq, skb);
+	hci_uart_tx_wakeup(hu);
+
+	if (mrvl_wait_for_hdr(hu, MRVL_HDR_REQ_FW) == -1)
+		return -1;
+
+	return 0;
+}
+
+/* Download firmware to the device */
+static int mrvl_dnld_fw(struct hci_uart *hu, const char *file_name)
+{
+	const struct firmware *fw = NULL;
+	struct sk_buff *skb = NULL;
+	int offset = 0;
+	int ret, tx_len;
+	struct mrvl_data *mrvl = hu->priv;
+	struct fw_data *fw_data = mrvl->fwdata;
+
+	ret = request_firmware(&fw, file_name, hu->tty->dev);
+	if (ret < 0) {
+		BT_ERR("request_firmware() failed");
+		return -1;
+	}
+
+	BT_INFO("Downloading FW (%d bytes)", (u16)fw->size);
+
+	fw_data->last_ack = 0;
+
+	while (1) {
+		if ((offset >= fw->size) || (fw_data->last_ack))
+			break;
+		tx_len = fw_data->next_len;
+		if ((fw->size - offset) < tx_len)
+			tx_len = fw->size - offset;
+
+		skb = bt_skb_alloc(MRVL_MAX_FW_BLOCK_SIZE, GFP_KERNEL);
+		if (!skb) {
+			ret = -1;
+			goto done;
+		}
+
+		memcpy(skb->data, &fw->data[offset], tx_len);
+		skb_put(skb, tx_len);
+		if (mrvl_send_data(hu, skb) != 0) {
+			BT_ERR("Fail to download firmware");
+			ret = -1;
+			goto done;
+		}
+		offset += tx_len;
+	}
+
+	BT_INFO("Downloaded %d byte firmware", offset);
+done:
+	release_firmware(fw);
+
+	return ret;
+}
+
+/* Set the baud rate */
+static int mrvl_set_dev_baud(struct hci_uart *hu)
+{
+	struct hci_dev *hdev = hu->hdev;
+	struct sk_buff *skb;
+	static const u8 baud_param[] = { 0xc0, 0xc6, 0x2d, 0x00 };
+	int err;
+
+	skb = __hci_cmd_sync(hdev, MRVL_HCI_OP_SET_BAUD, sizeof(baud_param),
+			     baud_param, HCI_INIT_TIMEOUT);
+	if (IS_ERR(skb)) {
+		err = PTR_ERR(skb);
+		bt_dev_err(hu->hdev, "Set device baudrate failed (%d)", err);
+		return err;
+	}
+	kfree_skb(skb);
+
+	return 0;
+}
+
+/* Reset device */
+static int mrvl_reset(struct hci_uart *hu)
+{
+	struct hci_dev *hdev = hu->hdev;
+	struct sk_buff *skb;
+	int err;
+
+	skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_CMD_TIMEOUT);
+	if (IS_ERR(skb)) {
+		err = PTR_ERR(skb);
+		bt_dev_err(hu->hdev, "Reset device failed (%d)", err);
+		return err;
+	}
+	kfree_skb(skb);
+
+	return 0;
+}
+
+static int mrvl_get_fw_name(struct hci_uart *hu, char *fw_name)
+{
+	struct mrvl_data *mrvl = hu->priv;
+	struct fw_data *fw_data = mrvl->fwdata;
+
+	if (mrvl_wait_for_hdr(hu, MRVL_HDR_CHIP_VER) != 0) {
+		BT_ERR("Could not read chip id and revision");
+		return -1;
+	}
+
+	BT_DBG("chip_id=0x%x, chip_rev=0x%x",
+	       fw_data->chip_id, fw_data->chip_rev);
+
+	switch (fw_data->chip_id) {
+	case MRVL_8997_CHIP_ID:
+		memcpy(fw_name, MRVL_8997_FW_NAME, sizeof(MRVL_8997_FW_NAME));
+		return 0;
+	default:
+		BT_ERR("Invalid chip id");
+		return -1;
+	}
+}
+
+/* Download helper and firmare to device */
+static int hci_uart_dnld_fw(struct hci_uart *hu)
+{
+	struct tty_struct *tty = hu->tty;
+	struct ktermios new_termios;
+	struct ktermios old_termios;
+	char fw_name[128];
+	int ret;
+
+	old_termios = tty->termios;
+
+	if (get_cts(hu)) {
+		BT_INFO("fw is running");
+		return 0;
+	}
+
+	hci_uart_set_baudrate(hu, 115200);
+	hci_uart_set_flow_control(hu, true);
+
+	ret = mrvl_wait_for_hdr(hu, MRVL_HDR_REQ_FW);
+	if (ret)
+		goto fail;
+
+	ret = mrvl_dnld_fw(hu, MRVL_HELPER_NAME);
+	if (ret)
+		goto fail;
+
+	msleep(MRVL_DNLD_DELAY);
+
+	hci_uart_set_baudrate(hu, 3000000);
+	hci_uart_set_flow_control(hu, false);
+
+	ret = mrvl_get_fw_name(hu, fw_name);
+	if (ret)
+		goto fail;
+
+	ret = mrvl_wait_for_hdr(hu, MRVL_HDR_REQ_FW);
+	if (ret)
+		goto fail;
+
+	ret = mrvl_dnld_fw(hu, fw_name);
+	if (ret)
+		goto fail;
+
+	msleep(MRVL_DNLD_DELAY);
+fail:
+	/* restore uart settings */
+	new_termios = tty->termios;
+	tty->termios.c_cflag = old_termios.c_cflag;
+	tty_set_termios(tty, &new_termios);
+
+	return ret;
+}
+
+static int mrvl_setup(struct hci_uart *hu)
+{
+	int err;
+
+	hci_uart_set_baudrate(hu, 115200);
+	hci_uart_set_flow_control(hu, false);
+
+	err = mrvl_reset(hu);
+	if (!err) {
+		err = mrvl_set_dev_baud(hu);
+		if (err)
+			return -1;
+	}
+
+	hci_uart_set_baudrate(hu, 3000000);
+	hci_uart_set_flow_control(hu, false);
+	msleep(MRVL_DNLD_DELAY);
+
+	return 0;
+}
+
+static int mrvl_prepare(struct hci_uart *hu)
+{
+	struct mrvl_data *mrvl = hu->priv;
+	int err;
+
+	err = mrvl_init_fw_data(hu);
+	if (!err)
+		err = hci_uart_dnld_fw(hu);
+
+	kfree(mrvl->fwdata);
+	return err;
+}
+
+static const struct hci_uart_proto mrvlp = {
+	.id		= HCI_UART_MRVL,
+	.name		= "MRVL",
+	.open		= mrvl_open,
+	.close		= mrvl_close,
+	.recv		= mrvl_recv,
+	.enqueue	= mrvl_enqueue,
+	.dequeue	= mrvl_dequeue,
+	.flush		= mrvl_flush,
+	.setup		= mrvl_setup,
+	.prepare	= mrvl_prepare,
+	.recv_for_prepare	= mrvl_recv_for_prepare,
+};
+
+int __init mrvl_init(void)
+{
+	return hci_uart_register_proto(&mrvlp);
+}
+
+int __exit mrvl_deinit(void)
+{
+	return hci_uart_unregister_proto(&mrvlp);
+}
diff --git a/drivers/bluetooth/hci_uart.h b/drivers/bluetooth/hci_uart.h
index 17ba3b4..8c53b50 100644
--- a/drivers/bluetooth/hci_uart.h
+++ b/drivers/bluetooth/hci_uart.h
@@ -35,7 +35,7 @@
 #define HCIUARTGETFLAGS		_IOR('U', 204, int)
 
 /* UART protocols */
-#define HCI_UART_MAX_PROTO	10
+#define HCI_UART_MAX_PROTO	11
 
 #define HCI_UART_H4	0
 #define HCI_UART_BCSP	1
@@ -47,6 +47,7 @@
 #define HCI_UART_BCM	7
 #define HCI_UART_QCA	8
 #define HCI_UART_AG6XX	9
+#define HCI_UART_MRVL	10
 
 #define HCI_UART_RAW_DEVICE	0
 #define HCI_UART_RESET_ON_INIT	1
@@ -192,3 +193,8 @@ int qca_deinit(void);
 int ag6xx_init(void);
 int ag6xx_deinit(void);
 #endif
+
+#ifdef CONFIG_BT_HCIUART_MRVL
+int mrvl_init(void);
+int mrvl_deinit(void);
+#endif
-- 
1.8.1.4

Re: [PATCH v12 3/3] Bluetooth: hci_uart: Support firmware download for Marvell

[Loic Poulain]

Hi Amit,

On 09/08/2016 18:32, Amitkumar Karwar wrote:
> From: Ganapathi Bhat <gbhat@marvell.com>
>
> This patch implement firmware download feature for
> Marvell Bluetooth devices. If firmware is already
> downloaded, it will skip downloading.
>
> Signed-off-by: Ganapathi Bhat <gbhat@marvell.com>
> Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
> Tested-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> ---
> v2: Fixed compilation warning reported by kbuild test robot
> v3: Addressed review comments from Marcel Holtmann
>      a) Removed vendor specific code from hci_ldisc.c
>      b) Get rid of static forward declaration
>      c) Removed unnecessary heavy nesting
>      d) Git rid of module parameter and global variables
>      e) Add logic to pick right firmware image
> v4: Addresses review comments from Alan
>      a) Use existing kernel helper APIs instead of writing own.
>      b) Replace mdelay() with msleep()
> v5: Addresses review comments from Loic Poulain
>      a) Use bt_dev_err/warn/dbg helpers insted of BT_ERR/WARN/DBG
>      b) Used static functions where required and removed forward delcarations
>      c) Edited comments for the function hci_uart_recv_data
>      d) Made HCI_UART_DNLD_FW flag a part of driver private data
> v6: Addresses review comments from Loic Poulain
>      a) Used skb instead of array to store firmware data during download
>      b) Used hci_uart_tx_wakeup and enqueued packets instead of tty write
>      c) Used GFP_KERNEL instead of GFP_ATOMIC
> v7: Edited Kconfig to add dependency for BT_HCIUART_H4. The change resolves
>      errors reported by kbuild test robot.
> v8: Addressed review comments from Marcel Holtmann
>      a) Removed unnecessary memory allocation failure messages
>      b) Get rid of btmrvl.h header file and add definitions in hci_mrvl.c file
> v9: Addressed review comments from Marcel Holtmann
>      a) Moved firmware download code from setup to prepare handler.
>      b) Change messages from bt_dev_*->BT_*, as hdev isn't available during firmware
>       download.
> v10: Addressed review comments from Marcel Holtmann
>      a) Added new callback recv_for_prepare to receive data from device
>       during prepare phase
>      b) Avoided using private flags (HCI_UART_DNLD_FW) as new receive callback is
>       added for the same purpose
>      c) Used kernel API to handle unaligned data
>      d) Moved mrvl_set_baud functionality inside setup callback
> v11: Write data through ldisc in mrvl_send_ack() instead of directly calling
>      write method(One Thousand Gnomes).
> v12: a) Check for buffer length before copying to skb (Loic Poulain)
>       b) Rearrange skb memory allocation check
> ---
>   drivers/bluetooth/Kconfig     |  11 +
>   drivers/bluetooth/Makefile    |   1 +
>   drivers/bluetooth/hci_ldisc.c |   6 +
>   drivers/bluetooth/hci_mrvl.c  | 545 ++++++++++++++++++++++++++++++++++++++++++
>   drivers/bluetooth/hci_uart.h  |   8 +-
>   5 files changed, 570 insertions(+), 1 deletion(-)
>   create mode 100644 drivers/bluetooth/hci_mrvl.c
>
> diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
> index cf50fd2..daafd0c 100644
> --- a/drivers/bluetooth/Kconfig
> +++ b/drivers/bluetooth/Kconfig
> @@ -180,6 +180,17 @@ config BT_HCIUART_AG6XX
>   
>   	  Say Y here to compile support for Intel AG6XX protocol.
>   
> +config BT_HCIUART_MRVL
> +	bool "Marvell protocol support"
> +	depends on BT_HCIUART
> +	select BT_HCIUART_H4
> +	help
> +	  Marvell is serial protocol for communication between Bluetooth
> +	  device and host. This protocol is required for most Marvell Bluetooth
> +	  devices with UART interface.
> +
> +	  Say Y here to compile support for HCI MRVL protocol.
> +
>   config BT_HCIBCM203X
>   	tristate "HCI BCM203x USB driver"
>   	depends on USB
> diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile
> index 9c18939..364dbb6 100644
> --- a/drivers/bluetooth/Makefile
> +++ b/drivers/bluetooth/Makefile
> @@ -37,6 +37,7 @@ hci_uart-$(CONFIG_BT_HCIUART_INTEL)	+= hci_intel.o
>   hci_uart-$(CONFIG_BT_HCIUART_BCM)	+= hci_bcm.o
>   hci_uart-$(CONFIG_BT_HCIUART_QCA)	+= hci_qca.o
>   hci_uart-$(CONFIG_BT_HCIUART_AG6XX)	+= hci_ag6xx.o
> +hci_uart-$(CONFIG_BT_HCIUART_MRVL)	+= hci_mrvl.o
>   hci_uart-objs				:= $(hci_uart-y)
>   
>   ccflags-y += -D__CHECK_ENDIAN__
> diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
> index 2c88586..ded13d3 100644
> --- a/drivers/bluetooth/hci_ldisc.c
> +++ b/drivers/bluetooth/hci_ldisc.c
> @@ -821,6 +821,9 @@ static int __init hci_uart_init(void)
>   #ifdef CONFIG_BT_HCIUART_AG6XX
>   	ag6xx_init();
>   #endif
> +#ifdef CONFIG_BT_HCIUART_MRVL
> +	mrvl_init();
> +#endif
>   
>   	return 0;
>   }
> @@ -856,6 +859,9 @@ static void __exit hci_uart_exit(void)
>   #ifdef CONFIG_BT_HCIUART_AG6XX
>   	ag6xx_deinit();
>   #endif
> +#ifdef CONFIG_BT_HCIUART_MRVL
> +	mrvl_deinit();
> +#endif
>   
>   	/* Release tty registration of line discipline */
>   	err = tty_unregister_ldisc(N_HCI);
> diff --git a/drivers/bluetooth/hci_mrvl.c b/drivers/bluetooth/hci_mrvl.c
> new file mode 100644
> index 0000000..c993c1b
> --- /dev/null
> +++ b/drivers/bluetooth/hci_mrvl.c
> @@ -0,0 +1,545 @@
> +/* Bluetooth HCI UART driver for Marvell devices
> + *
> + * Copyright (C) 2016, Marvell International Ltd.
> + *
> + *  Acknowledgements:
> + *  This file is based on hci_h4.c, which was written
> + *  by Maxim Krasnyansky and Marcel Holtmann.
> + *
> + * This software file (the "File") is distributed by Marvell International
> + * Ltd. under the terms of the GNU General Public License Version 2, June 1991
> + * (the "License").  You may use, redistribute and/or modify this File in
> + * accordance with the terms and conditions of the License, a copy of which
> + * is available on the worldwide web at
> + * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
> + *
> + * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
> + * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
> + * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
> + * this warranty disclaimer.
> + */
> +
> +#include <linux/firmware.h>
> +#include <linux/tty.h>
> +#include <asm/unaligned.h>
> +#include <net/bluetooth/bluetooth.h>
> +#include <net/bluetooth/hci_core.h>
> +#include "hci_uart.h"
> +
> +struct fw_data {
> +	wait_queue_head_t init_wait_q;
> +	u8 wait_fw;
> +	int next_len;
> +	u8 five_bytes[5];
> +	u8 next_index;
> +	u8 last_ack;
> +	u8 expected_ack;
> +	struct ktermios old_termios;
> +	u8 chip_id;
> +	u8 chip_rev;
> +	struct sk_buff *skb;
> +};
> +
> +#define MRVL_HELPER_NAME	"mrvl/helper_uart_3000000.bin"
> +#define MRVL_8997_CHIP_ID	0x50
> +#define MRVL_8997_FW_NAME	"mrvl/uart8997_bt.bin"
> +#define MRVL_MAX_FW_BLOCK_SIZE	1024
> +#define MRVL_MAX_RETRY_SEND	12
> +#define MRVL_DNLD_DELAY		100
> +#define MRVL_ACK		0x5A
> +#define MRVL_NAK		0xBF
> +#define MRVL_HDR_REQ_FW		0xA5
> +#define MRVL_HDR_CHIP_VER	0xAA
> +#define MRVL_HCI_OP_SET_BAUD	0xFC09
> +#define MRVL_FW_HDR_LEN		5
> +#define MRVL_WAIT_TIMEOUT	msecs_to_jiffies(12000)
> +
> +struct mrvl_data {
> +	struct sk_buff *rx_skb;
> +	struct sk_buff_head txq;
> +	struct fw_data *fwdata;
> +};
> +
> +static int get_cts(struct hci_uart *hu)
> +{
> +	struct tty_struct *tty = hu->tty;
> +	u32 state =  tty->ops->tiocmget(tty);
> +
> +	if (state & TIOCM_CTS) {
> +		bt_dev_dbg(hu->hdev, "CTS is low");
> +		return 1;
> +	}
> +	bt_dev_dbg(hu->hdev, "CTS is high");
> +
> +	return 0;
> +}
> +
> +/* Initialize protocol */
> +static int mrvl_open(struct hci_uart *hu)
> +{
> +	struct mrvl_data *mrvl;
> +
> +	bt_dev_dbg(hu->hdev, "hu %p", hu);
> +
> +	mrvl = kzalloc(sizeof(*mrvl), GFP_KERNEL);
> +	if (!mrvl)
> +		return -ENOMEM;
> +
> +	skb_queue_head_init(&mrvl->txq);
> +	hu->priv = mrvl;
> +
> +	return 0;
> +}
> +
> +/* Flush protocol data */
> +static int mrvl_flush(struct hci_uart *hu)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +
> +	bt_dev_dbg(hu->hdev, "hu %p", hu);
> +
> +	skb_queue_purge(&mrvl->txq);
> +
> +	return 0;
> +}
> +
> +/* Close protocol */
> +static int mrvl_close(struct hci_uart *hu)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +
> +	bt_dev_dbg(hu->hdev, "hu %p", hu);
> +
> +	skb_queue_purge(&mrvl->txq);
> +	kfree_skb(mrvl->rx_skb);
> +	hu->priv = NULL;
> +	kfree(mrvl);
> +
> +	return 0;
> +}
> +
> +/* Enqueue frame for transmittion (padding, crc, etc) */
> +static int mrvl_enqueue(struct hci_uart *hu, struct sk_buff *skb)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +
> +	bt_dev_dbg(hu->hdev, "hu %p skb %p", hu, skb);
> +
> +	/* Prepend skb with frame type */
> +	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
> +	skb_queue_tail(&mrvl->txq, skb);
> +
> +	return 0;
> +}
> +
> +static const struct h4_recv_pkt mrvl_recv_pkts[] = {
> +	{ H4_RECV_ACL,   .recv = hci_recv_frame },
> +	{ H4_RECV_SCO,   .recv = hci_recv_frame },
> +	{ H4_RECV_EVENT, .recv = hci_recv_frame },
> +};
> +
> +/* Send ACK/NAK to the device */
> +static void mrvl_send_ack(struct hci_uart *hu, unsigned char ack)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +	struct sk_buff *skb = NULL;
> +
> +	skb = bt_skb_alloc(sizeof(ack), GFP_KERNEL);
> +	if (!skb)
> +		return;
> +
> +	memcpy(skb->data, &ack, sizeof(ack));
> +	skb_put(skb, sizeof(ack));
> +	skb_queue_head(&mrvl->txq, skb);
> +	hci_uart_tx_wakeup(hu);
> +}
> +
> +/* Validate the feedback data from device */
> +static void mrvl_pkt_complete(struct hci_uart *hu, struct sk_buff *skb)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +	struct fw_data *fw_data = mrvl->fwdata;
> +	u16 lhs, rhs;
> +
> +	lhs = get_unaligned_le16(skb->data + 1);
> +	rhs = get_unaligned_le16(skb->data + 3);
> +	if ((lhs ^ rhs) == 0xffff) {
> +		mrvl_send_ack(hu, MRVL_ACK);
> +		fw_data->wait_fw = 1;
> +		fw_data->next_len = lhs;
> +		/* Firmware download is done, send the last ack */
> +		if (!lhs)
> +			fw_data->last_ack = 1;
> +
> +		if (fw_data->expected_ack == MRVL_HDR_CHIP_VER) {
> +			fw_data->chip_id = skb->data[1];
> +			fw_data->chip_rev = skb->data[2];
> +		}
> +		wake_up_interruptible(&fw_data->init_wait_q);
> +	} else {
> +		mrvl_send_ack(hu, MRVL_NAK);
> +	}
> +}
> +
> +/* This function receives data from the uart device during firmware download.
> + * Driver expects 5 bytes of data as per the protocal in the below format:
> + * <HEADER><BYTE_1><BYTE_2><BYTE_3><BYTE_4>
> + * BYTE_3 and BYTE_4 are compliment of BYTE_1 an BYTE_2. Data can come in chunks
> + * of any length. If length received is < 5, accumulate the data in an array,
> + * until we have a sequence of 5 bytes, starting with the expected HEADER. If
> + * the length received is > 5  bytes, then get the first 5 bytes, starting with
> + * the HEADER and process the same, ignoring the rest of the bytes as per the
> + * protocal.
> + */
> +static struct sk_buff *mrvl_process_fw_data(struct hci_uart *hu,
> +					    struct sk_buff *skb,
> +					    u8 *buf, int count)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +	struct fw_data *fw_data = mrvl->fwdata;
> +	int i = 0, len;
> +
> +	if (!skb) {
> +		while ((i < count) && buf[i] != fw_data->expected_ack)
> +			i++;
> +		if (i == count)
> +			return ERR_PTR(-EILSEQ);
> +
> +		skb = bt_skb_alloc(MRVL_FW_HDR_LEN, GFP_KERNEL);
> +		if (!skb)
> +			return ERR_PTR(-ENOMEM);
> +	}
> +
> +	len = count - i;
> +	if ((len + skb->len) > MRVL_FW_HDR_LEN)
> +		return ERR_PTR(-EILSEQ);
> +
> +	memcpy(skb_put(skb, len), &buf[i], len);
> +
> +	if (skb->len == MRVL_FW_HDR_LEN) {
> +		mrvl_pkt_complete(hu, skb);
> +		kfree_skb(skb);
> +		skb = NULL;
> +	}
> +
> +	return skb;
> +}
> +
> +/* Receive firmware feedback data */
> +static int mrvl_recv_for_prepare(struct hci_uart *hu, const void *data,
> +				 int count)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +
> +	mrvl->fwdata->skb = mrvl_process_fw_data(hu, mrvl->fwdata->skb,
> +						 (u8 *)data, count);
> +	if (IS_ERR(mrvl->fwdata->skb)) {
> +		int err = PTR_ERR(mrvl->fwdata->skb);
> +
> +		bt_dev_err(hu->hdev,
> +			   "Receive firmware data failed (%d)", err);
> +		mrvl->fwdata->skb = NULL;
> +		return err;
> +	}
> +
> +	return 0;
> +}

Don't understand why you need this 'prepare stuff', everything could be
done in setup procedure.

I think you only need to define your own vendor packets.

#define HCI_RECV_CHIP_VER \
     .type = HCI_CHIP_VER_PKT, \
     .hlen = HCI_MRVL_PKT_SIZE, \
     .loff = 0, \
     .lsize = 0, \
     .maxlen = HCI_MRVL_PKT_SIZE

#define HCI_RECV_FW_REQ \
     .type = HCI_FW_REQ_PKT, \
     .hlen = HCI_MRVL_PKT_SIZE, \
     .loff = 0, \
     .lsize = 0, \
     .maxlen = HCI_MRVL_PKT_SIZE

And add them in your supported list:

static const struct h4_recv_pkt mrvl_recv_pkts[] = {
     { H4_RECV_ACL,       .recv = hci_recv_frame   },
     { H4_RECV_SCO,       .recv = hci_recv_frame   },
     { H4_RECV_EVENT,     .recv = hci_recv_frame   },
     { HCI_RECV_FW_REQ,   .recv = mrvl_vendor_recv },
     { HCI_RECV_CHIP_VER, .recv = mrvl_vendor_recv },
};

>   
> +
> +/* Receive data */
> +static int mrvl_recv(struct hci_uart *hu, const void *data, int count)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +
> +	if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
> +		return -EUNATCH;
> +
> +	mrvl->rx_skb = h4_recv_buf(hu->hdev, mrvl->rx_skb, data, count,
> +				   mrvl_recv_pkts, ARRAY_SIZE(mrvl_recv_pkts));
> +	if (IS_ERR(mrvl->rx_skb)) {
> +		int err = PTR_ERR(mrvl->rx_skb);
> +
> +		bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
> +		mrvl->rx_skb = NULL;
> +		return err;
> +	}
> +
> +	return count;
> +}
> +
> +static struct sk_buff *mrvl_dequeue(struct hci_uart *hu)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +
> +	return skb_dequeue(&mrvl->txq);
> +}
> +
> +static int mrvl_init_fw_data(struct hci_uart *hu)
> +{
> +	struct fw_data *fwdata;
> +	struct mrvl_data *mrvl = hu->priv;
> +
> +	fwdata = kzalloc(sizeof(*fwdata), GFP_KERNEL);
> +	if (!fwdata)
> +		return -ENOMEM;
> +
> +	mrvl->fwdata = fwdata;
> +	init_waitqueue_head(&fwdata->init_wait_q);
> +
> +	return 0;
> +}
> +
> +/* Wait for the header from device */
> +static int mrvl_wait_for_hdr(struct hci_uart *hu, u8 header)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +	struct fw_data *fw_data = mrvl->fwdata;
> +
> +	fw_data->expected_ack = header;
> +	fw_data->wait_fw = 0;
> +
> +	if (!wait_event_interruptible_timeout(fw_data->init_wait_q,
> +					      fw_data->wait_fw,
> +					      MRVL_WAIT_TIMEOUT)) {
> +		BT_ERR("TIMEOUT, waiting for:0x%x", fw_data->expected_ack);
> +		return -1;
> +	}
> +
> +	return 0;
> +}
> +
> +/* Send bytes to device */
> +static int mrvl_send_data(struct hci_uart *hu, struct sk_buff *skb)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +
> +	skb_queue_head(&mrvl->txq, skb);
> +	hci_uart_tx_wakeup(hu);
> +
> +	if (mrvl_wait_for_hdr(hu, MRVL_HDR_REQ_FW) == -1)
> +		return -1;
> +
> +	return 0;
> +}
> +
> +/* Download firmware to the device */
> +static int mrvl_dnld_fw(struct hci_uart *hu, const char *file_name)
> +{
> +	const struct firmware *fw = NULL;
> +	struct sk_buff *skb = NULL;
> +	int offset = 0;
> +	int ret, tx_len;
> +	struct mrvl_data *mrvl = hu->priv;
> +	struct fw_data *fw_data = mrvl->fwdata;
> +
> +	ret = request_firmware(&fw, file_name, hu->tty->dev);
> +	if (ret < 0) {
> +		BT_ERR("request_firmware() failed");
> +		return -1;
> +	}
> +
> +	BT_INFO("Downloading FW (%d bytes)", (u16)fw->size);
> +
> +	fw_data->last_ack = 0;
> +
> +	while (1) {
> +		if ((offset >= fw->size) || (fw_data->last_ack))
> +			break;
> +		tx_len = fw_data->next_len;
> +		if ((fw->size - offset) < tx_len)
> +			tx_len = fw->size - offset;
> +
> +		skb = bt_skb_alloc(MRVL_MAX_FW_BLOCK_SIZE, GFP_KERNEL);

Why allocating the max size? you know the tx_len.

> +		if (!skb) {
> +			ret = -1;
> +			goto done;
> +		}
> +
> +		memcpy(skb->data, &fw->data[offset], tx_len);
> +		skb_put(skb, tx_len);
> +		if (mrvl_send_data(hu, skb) != 0) {
> +			BT_ERR("Fail to download firmware");
> +			ret = -1;
> +			goto done;
> +		}
> +		offset += tx_len;
> +	}
> +
> +	BT_INFO("Downloaded %d byte firmware", offset);
> +done:
> +	release_firmware(fw);
> +
> +	return ret;
> +}
> +
> +/* Set the baud rate */
> +static int mrvl_set_dev_baud(struct hci_uart *hu)
> +{
> +	struct hci_dev *hdev = hu->hdev;
> +	struct sk_buff *skb;
> +	static const u8 baud_param[] = { 0xc0, 0xc6, 0x2d, 0x00 };
> +	int err;
> +
> +	skb = __hci_cmd_sync(hdev, MRVL_HCI_OP_SET_BAUD, sizeof(baud_param),
> +			     baud_param, HCI_INIT_TIMEOUT);
> +	if (IS_ERR(skb)) {
> +		err = PTR_ERR(skb);
> +		bt_dev_err(hu->hdev, "Set device baudrate failed (%d)", err);
> +		return err;
> +	}
> +	kfree_skb(skb);
> +
> +	return 0;
> +}
> +
> +/* Reset device */
> +static int mrvl_reset(struct hci_uart *hu)
> +{
> +	struct hci_dev *hdev = hu->hdev;
> +	struct sk_buff *skb;
> +	int err;
> +
> +	skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_CMD_TIMEOUT);
> +	if (IS_ERR(skb)) {
> +		err = PTR_ERR(skb);
> +		bt_dev_err(hu->hdev, "Reset device failed (%d)", err);
> +		return err;
> +	}
> +	kfree_skb(skb);
> +
> +	return 0;
> +}
> +
> +static int mrvl_get_fw_name(struct hci_uart *hu, char *fw_name)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +	struct fw_data *fw_data = mrvl->fwdata;
> +
> +	if (mrvl_wait_for_hdr(hu, MRVL_HDR_CHIP_VER) != 0) {
> +		BT_ERR("Could not read chip id and revision");
> +		return -1;
> +	}
> +
> +	BT_DBG("chip_id=0x%x, chip_rev=0x%x",
> +	       fw_data->chip_id, fw_data->chip_rev);
> +
> +	switch (fw_data->chip_id) {
> +	case MRVL_8997_CHIP_ID:
> +		memcpy(fw_name, MRVL_8997_FW_NAME, sizeof(MRVL_8997_FW_NAME));
> +		return 0;
> +	default:
> +		BT_ERR("Invalid chip id");
> +		return -1;
> +	}
> +}
> +
> +/* Download helper and firmare to device */
> +static int hci_uart_dnld_fw(struct hci_uart *hu)
> +{
> +	struct tty_struct *tty = hu->tty;
> +	struct ktermios new_termios;
> +	struct ktermios old_termios;
> +	char fw_name[128];
> +	int ret;
> +
> +	old_termios = tty->termios;
> +
> +	if (get_cts(hu)) {
> +		BT_INFO("fw is running");
> +		return 0;
> +	}
> +
> +	hci_uart_set_baudrate(hu, 115200);
> +	hci_uart_set_flow_control(hu, true);
> +
> +	ret = mrvl_wait_for_hdr(hu, MRVL_HDR_REQ_FW);
> +	if (ret)
> +		goto fail;
> +
> +	ret = mrvl_dnld_fw(hu, MRVL_HELPER_NAME);
> +	if (ret)
> +		goto fail;
> +
> +	msleep(MRVL_DNLD_DELAY);
> +
> +	hci_uart_set_baudrate(hu, 3000000);
> +	hci_uart_set_flow_control(hu, false);
> +
> +	ret = mrvl_get_fw_name(hu, fw_name);
> +	if (ret)
> +		goto fail;
> +
> +	ret = mrvl_wait_for_hdr(hu, MRVL_HDR_REQ_FW);
> +	if (ret)
> +		goto fail;
> +
> +	ret = mrvl_dnld_fw(hu, fw_name);
> +	if (ret)
> +		goto fail;
> +
> +	msleep(MRVL_DNLD_DELAY);
> +fail:
> +	/* restore uart settings */
> +	new_termios = tty->termios;
> +	tty->termios.c_cflag = old_termios.c_cflag;
> +	tty_set_termios(tty, &new_termios);
> +
> +	return ret;
> +}
> +
> +static int mrvl_setup(struct hci_uart *hu)
> +{
> +	int err;
> +
> +	hci_uart_set_baudrate(hu, 115200);

Should be done with init_speed.

> +	hci_uart_set_flow_control(hu, false);
> +
> +	err = mrvl_reset(hu);
> +	if (!err) {
> +		err = mrvl_set_dev_baud(hu);
> +		if (err)
> +			return -1;
> +	}
> +
> +	hci_uart_set_baudrate(hu, 3000000);
> +	hci_uart_set_flow_control(hu, false);
> +	msleep(MRVL_DNLD_DELAY);
> +
> +	return 0;
> +}
> +
> +static int mrvl_prepare(struct hci_uart *hu)
> +{
> +	struct mrvl_data *mrvl = hu->priv;
> +	int err;
> +
> +	err = mrvl_init_fw_data(hu);
> +	if (!err)
> +		err = hci_uart_dnld_fw(hu);
> +
> +	kfree(mrvl->fwdata);
> +	return err;
> +}
>

Regards,
Loic

RE: [PATCH v12 3/3] Bluetooth: hci_uart: Support firmware download for Marvell

[Amitkumar Karwar]

Hi Loic,

Thanks for your comments.

> -----Original Message-----
> From: Loic Poulain [mailto:loic.poulain@intel.com]
> Sent: Tuesday, August 16, 2016 1:20 PM
> To: Amitkumar Karwar; linux-bluetooth@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org; linux-rockchip@lists.infradead.org;
> marcel@holtmann.org; Ganapathi Bhat
> Subject: Re: [PATCH v12 3/3] Bluetooth: hci_uart: Support firmware
> download for Marvell
> 
> Hi Amit,
> 
> On 09/08/2016 18:32, Amitkumar Karwar wrote:
> > From: Ganapathi Bhat <gbhat@marvell.com>
> >
> > This patch implement firmware download feature for Marvell Bluetooth
> > devices. If firmware is already downloaded, it will skip downloading.
> >
> > Signed-off-by: Ganapathi Bhat <gbhat@marvell.com>
> > Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
> > Tested-by: Jeffy Chen <jeffy.chen@rock-chips.com>
> > ---
> > v2: Fixed compilation warning reported by kbuild test robot
> > v3: Addressed review comments from Marcel Holtmann
> >      a) Removed vendor specific code from hci_ldisc.c
> >      b) Get rid of static forward declaration
> >      c) Removed unnecessary heavy nesting
> >      d) Git rid of module parameter and global variables
> >      e) Add logic to pick right firmware image
> > v4: Addresses review comments from Alan
> >      a) Use existing kernel helper APIs instead of writing own.
> >      b) Replace mdelay() with msleep()
> > v5: Addresses review comments from Loic Poulain
> >      a) Use bt_dev_err/warn/dbg helpers insted of BT_ERR/WARN/DBG
> >      b) Used static functions where required and removed forward
> delcarations
> >      c) Edited comments for the function hci_uart_recv_data
> >      d) Made HCI_UART_DNLD_FW flag a part of driver private data
> > v6: Addresses review comments from Loic Poulain
> >      a) Used skb instead of array to store firmware data during
> download
> >      b) Used hci_uart_tx_wakeup and enqueued packets instead of tty
> write
> >      c) Used GFP_KERNEL instead of GFP_ATOMIC
> > v7: Edited Kconfig to add dependency for BT_HCIUART_H4. The change
> resolves
> >      errors reported by kbuild test robot.
> > v8: Addressed review comments from Marcel Holtmann
> >      a) Removed unnecessary memory allocation failure messages
> >      b) Get rid of btmrvl.h header file and add definitions in
> > hci_mrvl.c file
> > v9: Addressed review comments from Marcel Holtmann
> >      a) Moved firmware download code from setup to prepare handler.
> >      b) Change messages from bt_dev_*->BT_*, as hdev isn't available
> during firmware
> >       download.
> > v10: Addressed review comments from Marcel Holtmann
> >      a) Added new callback recv_for_prepare to receive data from
> device
> >       during prepare phase
> >      b) Avoided using private flags (HCI_UART_DNLD_FW) as new receive
> callback is
> >       added for the same purpose
> >      c) Used kernel API to handle unaligned data
> >      d) Moved mrvl_set_baud functionality inside setup callback
> > v11: Write data through ldisc in mrvl_send_ack() instead of directly
> calling
> >      write method(One Thousand Gnomes).
> > v12: a) Check for buffer length before copying to skb (Loic Poulain)
> >       b) Rearrange skb memory allocation check
> > ---
> >   drivers/bluetooth/Kconfig     |  11 +
> >   drivers/bluetooth/Makefile    |   1 +
> >   drivers/bluetooth/hci_ldisc.c |   6 +
> >   drivers/bluetooth/hci_mrvl.c  | 545
> ++++++++++++++++++++++++++++++++++++++++++
> >   drivers/bluetooth/hci_uart.h  |   8 +-
> >   5 files changed, 570 insertions(+), 1 deletion(-)
> >   create mode 100644 drivers/bluetooth/hci_mrvl.c
> >
> > diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
> > index cf50fd2..daafd0c 100644
> > --- a/drivers/bluetooth/Kconfig
> > +++ b/drivers/bluetooth/Kconfig
> > @@ -180,6 +180,17 @@ config BT_HCIUART_AG6XX
> >
> >   	  Say Y here to compile support for Intel AG6XX protocol.
> >
> > +config BT_HCIUART_MRVL
> > +	bool "Marvell protocol support"
> > +	depends on BT_HCIUART
> > +	select BT_HCIUART_H4
> > +	help
> > +	  Marvell is serial protocol for communication between Bluetooth
> > +	  device and host. This protocol is required for most Marvell
> Bluetooth
> > +	  devices with UART interface.
> > +
> > +	  Say Y here to compile support for HCI MRVL protocol.
> > +
> >   config BT_HCIBCM203X
> >   	tristate "HCI BCM203x USB driver"
> >   	depends on USB
> > diff --git a/drivers/bluetooth/Makefile b/drivers/bluetooth/Makefile
> > index 9c18939..364dbb6 100644
> > --- a/drivers/bluetooth/Makefile
> > +++ b/drivers/bluetooth/Makefile
> > @@ -37,6 +37,7 @@ hci_uart-$(CONFIG_BT_HCIUART_INTEL)	+= hci_intel.o
> >   hci_uart-$(CONFIG_BT_HCIUART_BCM)	+= hci_bcm.o
> >   hci_uart-$(CONFIG_BT_HCIUART_QCA)	+= hci_qca.o
> >   hci_uart-$(CONFIG_BT_HCIUART_AG6XX)	+= hci_ag6xx.o
> > +hci_uart-$(CONFIG_BT_HCIUART_MRVL)	+= hci_mrvl.o
> >   hci_uart-objs				:= $(hci_uart-y)
> >
> >   ccflags-y += -D__CHECK_ENDIAN__
> > diff --git a/drivers/bluetooth/hci_ldisc.c
> > b/drivers/bluetooth/hci_ldisc.c index 2c88586..ded13d3 100644
> > --- a/drivers/bluetooth/hci_ldisc.c
> > +++ b/drivers/bluetooth/hci_ldisc.c
> > @@ -821,6 +821,9 @@ static int __init hci_uart_init(void)
> >   #ifdef CONFIG_BT_HCIUART_AG6XX
> >   	ag6xx_init();
> >   #endif
> > +#ifdef CONFIG_BT_HCIUART_MRVL
> > +	mrvl_init();
> > +#endif
> >
> >   	return 0;
> >   }
> > @@ -856,6 +859,9 @@ static void __exit hci_uart_exit(void)
> >   #ifdef CONFIG_BT_HCIUART_AG6XX
> >   	ag6xx_deinit();
> >   #endif
> > +#ifdef CONFIG_BT_HCIUART_MRVL
> > +	mrvl_deinit();
> > +#endif
> >
> >   	/* Release tty registration of line discipline */
> >   	err = tty_unregister_ldisc(N_HCI);
> > diff --git a/drivers/bluetooth/hci_mrvl.c
> > b/drivers/bluetooth/hci_mrvl.c new file mode 100644 index
> > 0000000..c993c1b
> > --- /dev/null
> > +++ b/drivers/bluetooth/hci_mrvl.c
> > @@ -0,0 +1,545 @@
> > +/* Bluetooth HCI UART driver for Marvell devices
> > + *
> > + * Copyright (C) 2016, Marvell International Ltd.
> > + *
> > + *  Acknowledgements:
> > + *  This file is based on hci_h4.c, which was written
> > + *  by Maxim Krasnyansky and Marcel Holtmann.
> > + *
> > + * This software file (the "File") is distributed by Marvell
> > +International
> > + * Ltd. under the terms of the GNU General Public License Version 2,
> > +June 1991
> > + * (the "License").  You may use, redistribute and/or modify this
> > +File in
> > + * accordance with the terms and conditions of the License, a copy of
> > +which
> > + * is available on the worldwide web at
> > + * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
> > + *
> > + * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND
> > +THE
> > + * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
> > +PURPOSE
> > + * ARE EXPRESSLY DISCLAIMED.  The License provides additional details
> > +about
> > + * this warranty disclaimer.
> > + */
> > +
> > +#include <linux/firmware.h>
> > +#include <linux/tty.h>
> > +#include <asm/unaligned.h>
> > +#include <net/bluetooth/bluetooth.h>
> > +#include <net/bluetooth/hci_core.h>
> > +#include "hci_uart.h"
> > +
> > +struct fw_data {
> > +	wait_queue_head_t init_wait_q;
> > +	u8 wait_fw;
> > +	int next_len;
> > +	u8 five_bytes[5];
> > +	u8 next_index;
> > +	u8 last_ack;
> > +	u8 expected_ack;
> > +	struct ktermios old_termios;
> > +	u8 chip_id;
> > +	u8 chip_rev;
> > +	struct sk_buff *skb;
> > +};
> > +
> > +#define MRVL_HELPER_NAME	"mrvl/helper_uart_3000000.bin"
> > +#define MRVL_8997_CHIP_ID	0x50
> > +#define MRVL_8997_FW_NAME	"mrvl/uart8997_bt.bin"
> > +#define MRVL_MAX_FW_BLOCK_SIZE	1024
> > +#define MRVL_MAX_RETRY_SEND	12
> > +#define MRVL_DNLD_DELAY		100
> > +#define MRVL_ACK		0x5A
> > +#define MRVL_NAK		0xBF
> > +#define MRVL_HDR_REQ_FW		0xA5
> > +#define MRVL_HDR_CHIP_VER	0xAA
> > +#define MRVL_HCI_OP_SET_BAUD	0xFC09
> > +#define MRVL_FW_HDR_LEN		5
> > +#define MRVL_WAIT_TIMEOUT	msecs_to_jiffies(12000)
> > +
> > +struct mrvl_data {
> > +	struct sk_buff *rx_skb;
> > +	struct sk_buff_head txq;
> > +	struct fw_data *fwdata;
> > +};
> > +
> > +static int get_cts(struct hci_uart *hu) {
> > +	struct tty_struct *tty = hu->tty;
> > +	u32 state =  tty->ops->tiocmget(tty);
> > +
> > +	if (state & TIOCM_CTS) {
> > +		bt_dev_dbg(hu->hdev, "CTS is low");
> > +		return 1;
> > +	}
> > +	bt_dev_dbg(hu->hdev, "CTS is high");
> > +
> > +	return 0;
> > +}
> > +
> > +/* Initialize protocol */
> > +static int mrvl_open(struct hci_uart *hu) {
> > +	struct mrvl_data *mrvl;
> > +
> > +	bt_dev_dbg(hu->hdev, "hu %p", hu);
> > +
> > +	mrvl = kzalloc(sizeof(*mrvl), GFP_KERNEL);
> > +	if (!mrvl)
> > +		return -ENOMEM;
> > +
> > +	skb_queue_head_init(&mrvl->txq);
> > +	hu->priv = mrvl;
> > +
> > +	return 0;
> > +}
> > +
> > +/* Flush protocol data */
> > +static int mrvl_flush(struct hci_uart *hu) {
> > +	struct mrvl_data *mrvl = hu->priv;
> > +
> > +	bt_dev_dbg(hu->hdev, "hu %p", hu);
> > +
> > +	skb_queue_purge(&mrvl->txq);
> > +
> > +	return 0;
> > +}
> > +
> > +/* Close protocol */
> > +static int mrvl_close(struct hci_uart *hu) {
> > +	struct mrvl_data *mrvl = hu->priv;
> > +
> > +	bt_dev_dbg(hu->hdev, "hu %p", hu);
> > +
> > +	skb_queue_purge(&mrvl->txq);
> > +	kfree_skb(mrvl->rx_skb);
> > +	hu->priv = NULL;
> > +	kfree(mrvl);
> > +
> > +	return 0;
> > +}
> > +
> > +/* Enqueue frame for transmittion (padding, crc, etc) */ static int
> > +mrvl_enqueue(struct hci_uart *hu, struct sk_buff *skb) {
> > +	struct mrvl_data *mrvl = hu->priv;
> > +
> > +	bt_dev_dbg(hu->hdev, "hu %p skb %p", hu, skb);
> > +
> > +	/* Prepend skb with frame type */
> > +	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
> > +	skb_queue_tail(&mrvl->txq, skb);
> > +
> > +	return 0;
> > +}
> > +
> > +static const struct h4_recv_pkt mrvl_recv_pkts[] = {
> > +	{ H4_RECV_ACL,   .recv = hci_recv_frame },
> > +	{ H4_RECV_SCO,   .recv = hci_recv_frame },
> > +	{ H4_RECV_EVENT, .recv = hci_recv_frame }, };
> > +
> > +/* Send ACK/NAK to the device */
> > +static void mrvl_send_ack(struct hci_uart *hu, unsigned char ack) {
> > +	struct mrvl_data *mrvl = hu->priv;
> > +	struct sk_buff *skb = NULL;
> > +
> > +	skb = bt_skb_alloc(sizeof(ack), GFP_KERNEL);
> > +	if (!skb)
> > +		return;
> > +
> > +	memcpy(skb->data, &ack, sizeof(ack));
> > +	skb_put(skb, sizeof(ack));
> > +	skb_queue_head(&mrvl->txq, skb);
> > +	hci_uart_tx_wakeup(hu);
> > +}
> > +
> > +/* Validate the feedback data from device */ static void
> > +mrvl_pkt_complete(struct hci_uart *hu, struct sk_buff *skb) {
> > +	struct mrvl_data *mrvl = hu->priv;
> > +	struct fw_data *fw_data = mrvl->fwdata;
> > +	u16 lhs, rhs;
> > +
> > +	lhs = get_unaligned_le16(skb->data + 1);
> > +	rhs = get_unaligned_le16(skb->data + 3);
> > +	if ((lhs ^ rhs) == 0xffff) {
> > +		mrvl_send_ack(hu, MRVL_ACK);
> > +		fw_data->wait_fw = 1;
> > +		fw_data->next_len = lhs;
> > +		/* Firmware download is done, send the last ack */
> > +		if (!lhs)
> > +			fw_data->last_ack = 1;
> > +
> > +		if (fw_data->expected_ack == MRVL_HDR_CHIP_VER) {
> > +			fw_data->chip_id = skb->data[1];
> > +			fw_data->chip_rev = skb->data[2];
> > +		}
> > +		wake_up_interruptible(&fw_data->init_wait_q);
> > +	} else {
> > +		mrvl_send_ack(hu, MRVL_NAK);
> > +	}
> > +}
> > +
> > +/* This function receives data from the uart device during firmware
> download.
> > + * Driver expects 5 bytes of data as per the protocal in the below
> format:
> > + * <HEADER><BYTE_1><BYTE_2><BYTE_3><BYTE_4>
> > + * BYTE_3 and BYTE_4 are compliment of BYTE_1 an BYTE_2. Data can
> > +come in chunks
> > + * of any length. If length received is < 5, accumulate the data in
> > +an array,
> > + * until we have a sequence of 5 bytes, starting with the expected
> > +HEADER. If
> > + * the length received is > 5  bytes, then get the first 5 bytes,
> > +starting with
> > + * the HEADER and process the same, ignoring the rest of the bytes as
> > +per the
> > + * protocal.
> > + */
> > +static struct sk_buff *mrvl_process_fw_data(struct hci_uart *hu,
> > +					    struct sk_buff *skb,
> > +					    u8 *buf, int count)
> > +{
> > +	struct mrvl_data *mrvl = hu->priv;
> > +	struct fw_data *fw_data = mrvl->fwdata;
> > +	int i = 0, len;
> > +
> > +	if (!skb) {
> > +		while ((i < count) && buf[i] != fw_data->expected_ack)
> > +			i++;
> > +		if (i == count)
> > +			return ERR_PTR(-EILSEQ);
> > +
> > +		skb = bt_skb_alloc(MRVL_FW_HDR_LEN, GFP_KERNEL);
> > +		if (!skb)
> > +			return ERR_PTR(-ENOMEM);
> > +	}
> > +
> > +	len = count - i;
> > +	if ((len + skb->len) > MRVL_FW_HDR_LEN)
> > +		return ERR_PTR(-EILSEQ);
> > +
> > +	memcpy(skb_put(skb, len), &buf[i], len);
> > +
> > +	if (skb->len == MRVL_FW_HDR_LEN) {
> > +		mrvl_pkt_complete(hu, skb);
> > +		kfree_skb(skb);
> > +		skb = NULL;
> > +	}
> > +
> > +	return skb;
> > +}
> > +
> > +/* Receive firmware feedback data */
> > +static int mrvl_recv_for_prepare(struct hci_uart *hu, const void
> *data,
> > +				 int count)
> > +{
> > +	struct mrvl_data *mrvl = hu->priv;
> > +
> > +	mrvl->fwdata->skb = mrvl_process_fw_data(hu, mrvl->fwdata->skb,
> > +						 (u8 *)data, count);
> > +	if (IS_ERR(mrvl->fwdata->skb)) {
> > +		int err = PTR_ERR(mrvl->fwdata->skb);
> > +
> > +		bt_dev_err(hu->hdev,
> > +			   "Receive firmware data failed (%d)", err);
> > +		mrvl->fwdata->skb = NULL;
> > +		return err;
> > +	}
> > +
> > +	return 0;
> > +}
> 
> Don't understand why you need this 'prepare stuff', everything could be
> done in setup procedure.

We had our firmware download code in setup handler in initial versions of this patch. Marcel pointed out that firmware download in ->setup() is fine as long as it uses HCI commands. We don't use HCI commands for FW download. Assumption in ->setup handler is we are in an HCI capable transport and it is ready.

So we came up with prepare handler.

I have addressed your other comments in V13 patch. I will send it shortly.

Regards,
Amitkumar Karwar