[PATCH v2 1/3] Bluetooth: hci_qca: Add support for QTI Bluetooth chip wcn6750

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Added regulators,GPIOs and changes required to power on/off wcn6750.
Added support for firmware download for wcn6750.

Changes done in detail:
1. Added regulators and corresponding current values.
2. Added sw_ctrl GPIO pin which is output from BT SoC and indicates
   status of clock supply to BT SoC.
3. Added inline function to check if the SoC type is wcn399x or wcn6750.
4. Modified the function qca_wcn3990_init() to support wcn6750 and
   renamed it to qca_regulator_init().
5. Added BT_ON and BT_OFF macros.
6. Added support to download mbn type firmware image as wcn6750 supports
   mbn type image.
7. If mbn type image is not present then we will check for tlv type image.
8. Moved extracting rom version info to common place as this code is
   common in all if else ladder in qca_uart_setup.

Signed-off-by: Venkata Lakshmi Narayana Gubba <gubbaven@xxxxxxxxxxxxxx>
---
 drivers/bluetooth/btqca.c   |  88 ++++++++++++++++++++++++++----------
 drivers/bluetooth/btqca.h   |  15 ++++++-
 drivers/bluetooth/hci_qca.c | 106 ++++++++++++++++++++++++++++++++++----------
 3 files changed, 161 insertions(+), 48 deletions(-)

diff --git a/drivers/bluetooth/btqca.c b/drivers/bluetooth/btqca.c
index 25114f0..eec391a 100644
--- a/drivers/bluetooth/btqca.c
+++ b/drivers/bluetooth/btqca.c
@@ -182,7 +182,8 @@ int qca_send_pre_shutdown_cmd(struct hci_dev *hdev)
 }
 EXPORT_SYMBOL_GPL(qca_send_pre_shutdown_cmd);
 
-static void qca_tlv_check_data(struct qca_fw_config *config,
+static void qca_tlv_check_data(struct hci_dev *hdev,
+			       struct qca_fw_config *config,
 		const struct firmware *fw, enum qca_btsoc_type soc_type)
 {
 	const u8 *data;
@@ -194,19 +195,21 @@ static void qca_tlv_check_data(struct qca_fw_config *config,
 	struct tlv_type_nvm *tlv_nvm;
 	uint8_t nvm_baud_rate = config->user_baud_rate;
 
-	tlv = (struct tlv_type_hdr *)fw->data;
-
-	type_len = le32_to_cpu(tlv->type_len);
-	length = (type_len >> 8) & 0x00ffffff;
-
-	BT_DBG("TLV Type\t\t : 0x%x", type_len & 0x000000ff);
-	BT_DBG("Length\t\t : %d bytes", length);
-
 	config->dnld_mode = QCA_SKIP_EVT_NONE;
 	config->dnld_type = QCA_SKIP_EVT_NONE;
 
 	switch (config->type) {
+	case ELF_TYPE_PATCH:
+		config->dnld_mode = QCA_SKIP_EVT_VSE_CC;
+		config->dnld_type = QCA_SKIP_EVT_VSE_CC;
+
+		bt_dev_dbg(hdev, "File Class        : 0x%x", fw->data[4]);
+		bt_dev_dbg(hdev, "Data Encoding     : 0x%x", fw->data[5]);
+		bt_dev_dbg(hdev, "File version      : 0x%x", fw->data[6]);
+		break;
 	case TLV_TYPE_PATCH:
+		tlv = (struct tlv_type_hdr *)fw->data;
+		type_len = le32_to_cpu(tlv->type_len);
 		tlv_patch = (struct tlv_type_patch *)tlv->data;
 
 		/* For Rome version 1.1 to 3.1, all segment commands
@@ -218,6 +221,7 @@ static void qca_tlv_check_data(struct qca_fw_config *config,
 		config->dnld_mode = tlv_patch->download_mode;
 		config->dnld_type = config->dnld_mode;
 
+		BT_DBG("TLV Type\t\t : 0x%x", type_len & 0x000000ff);
 		BT_DBG("Total Length           : %d bytes",
 		       le32_to_cpu(tlv_patch->total_size));
 		BT_DBG("Patch Data Length      : %d bytes",
@@ -243,6 +247,14 @@ static void qca_tlv_check_data(struct qca_fw_config *config,
 		break;
 
 	case TLV_TYPE_NVM:
+		tlv = (struct tlv_type_hdr *)fw->data;
+
+		type_len = le32_to_cpu(tlv->type_len);
+		length = (type_len >> 8) & 0x00ffffff;
+
+		BT_DBG("TLV Type\t\t : 0x%x", type_len & 0x000000ff);
+		BT_DBG("Length\t\t : %d bytes", length);
+
 		idx = 0;
 		data = tlv->data;
 		while (idx < length) {
@@ -387,7 +399,8 @@ static int qca_inject_cmd_complete_event(struct hci_dev *hdev)
 
 static int qca_download_firmware(struct hci_dev *hdev,
 				 struct qca_fw_config *config,
-				 enum qca_btsoc_type soc_type)
+				 enum qca_btsoc_type soc_type,
+				 u8 rom_ver)
 {
 	const struct firmware *fw;
 	const u8 *segment;
@@ -397,12 +410,29 @@ static int qca_download_firmware(struct hci_dev *hdev,
 
 	ret = request_firmware(&fw, config->fwname, &hdev->dev);
 	if (ret) {
-		bt_dev_err(hdev, "QCA Failed to request file: %s (%d)",
-			   config->fwname, ret);
-		return ret;
+		/* For WCN6750, if mbn file is not present then check for
+		 * tlv file.
+		 */
+		if (soc_type == QCA_WCN6750 && config->type == ELF_TYPE_PATCH) {
+			bt_dev_dbg(hdev, "QCA Failed to request file: %s (%d)",
+				   config->fwname, ret);
+			config->type = TLV_TYPE_PATCH;
+			snprintf(config->fwname, sizeof(config->fwname),
+				 "qca/msbtfw%02x.tlv", rom_ver);
+			ret = request_firmware(&fw, config->fwname, &hdev->dev);
+			if (ret) {
+				bt_dev_err(hdev, "QCA Failed to request file: %s (%d)",
+					   config->fwname, ret);
+				return ret;
+			}
+		} else {
+			bt_dev_err(hdev, "QCA Failed to request file: %s (%d)",
+				   config->fwname, ret);
+			return ret;
+		}
 	}
 
-	qca_tlv_check_data(config, fw, soc_type);
+	qca_tlv_check_data(hdev, config, fw, soc_type);
 
 	segment = fw->data;
 	remain = fw->size;
@@ -502,27 +532,33 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t baudrate,
 
 	config.user_baud_rate = baudrate;
 
+	/* Firmware files to download are based on ROM version.
+	 * ROM version is derived from last two bytes of soc_ver.
+	 */
+	rom_ver = ((soc_ver & 0x00000f00) >> 0x04) |
+		    (soc_ver & 0x0000000f);
+
 	/* Download rampatch file */
 	config.type = TLV_TYPE_PATCH;
 	if (qca_is_wcn399x(soc_type)) {
-		/* Firmware files to download are based on ROM version.
-		 * ROM version is derived from last two bytes of soc_ver.
-		 */
-		rom_ver = ((soc_ver & 0x00000f00) >> 0x04) |
-			    (soc_ver & 0x0000000f);
 		snprintf(config.fwname, sizeof(config.fwname),
 			 "qca/crbtfw%02x.tlv", rom_ver);
 	} else if (soc_type == QCA_QCA6390) {
-		rom_ver = ((soc_ver & 0x00000f00) >> 0x04) |
-			    (soc_ver & 0x0000000f);
 		snprintf(config.fwname, sizeof(config.fwname),
 			 "qca/htbtfw%02x.tlv", rom_ver);
+	} else if (soc_type == QCA_WCN6750) {
+		/* Choose mbn file by default.If mbn file is not found
+		 * then choose tlv file
+		 */
+		config.type = ELF_TYPE_PATCH;
+		snprintf(config.fwname, sizeof(config.fwname),
+			 "qca/msbtfw%02x.mbn", rom_ver);
 	} else {
 		snprintf(config.fwname, sizeof(config.fwname),
 			 "qca/rampatch_%08x.bin", soc_ver);
 	}
 
-	err = qca_download_firmware(hdev, &config, soc_type);
+	err = qca_download_firmware(hdev, &config, soc_type, rom_ver);
 	if (err < 0) {
 		bt_dev_err(hdev, "QCA Failed to download patch (%d)", err);
 		return err;
@@ -548,11 +584,14 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t baudrate,
 	else if (soc_type == QCA_QCA6390)
 		snprintf(config.fwname, sizeof(config.fwname),
 			 "qca/htnv%02x.bin", rom_ver);
+	else if (soc_type == QCA_WCN6750)
+		snprintf(config.fwname, sizeof(config.fwname),
+			 "qca/msnv%02x.bin", rom_ver);
 	else
 		snprintf(config.fwname, sizeof(config.fwname),
 			 "qca/nvm_%08x.bin", soc_ver);
 
-	err = qca_download_firmware(hdev, &config, soc_type);
+	err = qca_download_firmware(hdev, &config, soc_type, rom_ver);
 	if (err < 0) {
 		bt_dev_err(hdev, "QCA Failed to download NVM (%d)", err);
 		return err;
@@ -564,13 +603,14 @@ int qca_uart_setup(struct hci_dev *hdev, uint8_t baudrate,
 			return err;
 	}
 
-	/* WCN399x supports the Microsoft vendor extension with 0xFD70 as the
+	/* WCN399x and WCN6750 supports the Microsoft vendor extension with 0xFD70 as the
 	 * VsMsftOpCode.
 	 */
 	switch (soc_type) {
 	case QCA_WCN3990:
 	case QCA_WCN3991:
 	case QCA_WCN3998:
+	case QCA_WCN6750:
 		hci_set_msft_opcode(hdev, 0xFD70);
 		break;
 	default:
diff --git a/drivers/bluetooth/btqca.h b/drivers/bluetooth/btqca.h
index b19add7..3057bf8 100644
--- a/drivers/bluetooth/btqca.h
+++ b/drivers/bluetooth/btqca.h
@@ -80,7 +80,8 @@ enum qca_tlv_dnld_mode {
 
 enum qca_tlv_type {
 	TLV_TYPE_PATCH = 1,
-	TLV_TYPE_NVM
+	TLV_TYPE_NVM,
+	ELF_TYPE_PATCH
 };
 
 struct qca_fw_config {
@@ -143,6 +144,7 @@ enum qca_btsoc_type {
 	QCA_WCN3998,
 	QCA_WCN3991,
 	QCA_QCA6390,
+	QCA_WCN6750
 };
 
 #if IS_ENABLED(CONFIG_BT_QCA)
@@ -160,6 +162,12 @@ static inline bool qca_is_wcn399x(enum qca_btsoc_type soc_type)
 	return soc_type == QCA_WCN3990 || soc_type == QCA_WCN3991 ||
 	       soc_type == QCA_WCN3998;
 }
+static inline bool qca_is_wcn399x_wcn6750(enum qca_btsoc_type soc_type)
+{
+	return soc_type == QCA_WCN3990 || soc_type == QCA_WCN3991 ||
+	       soc_type == QCA_WCN3998 || soc_type == QCA_WCN6750;
+}
+
 #else
 
 static inline int qca_set_bdaddr_rome(struct hci_dev *hdev, const bdaddr_t *bdaddr)
@@ -192,6 +200,11 @@ static inline bool qca_is_wcn399x(enum qca_btsoc_type soc_type)
 	return false;
 }
 
+static inline bool qca_is_wcn399x_wcn6750(enum qca_btsoc_type soc_type)
+{
+	return false;
+}
+
 static inline int qca_send_pre_shutdown_cmd(struct hci_dev *hdev)
 {
 	return -EOPNOTSUPP;
diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index 0a00569..0d25ba9 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -70,6 +70,10 @@
 #define QCA_CRASHBYTE_PACKET_LEN	1096
 #define QCA_MEMDUMP_BYTE		0xFB
 
+/* BT_EN GPIO enable/disable */
+#define BT_ON		1
+#define BT_OFF		0
+
 enum qca_flags {
 	QCA_IBS_DISABLED,
 	QCA_DROP_VENDOR_EVENT,
@@ -218,6 +222,7 @@ struct qca_power {
 struct qca_serdev {
 	struct hci_uart	 serdev_hu;
 	struct gpio_desc *bt_en;
+	struct gpio_desc *sw_ctrl;
 	struct clk	 *susclk;
 	enum qca_btsoc_type btsoc_type;
 	struct qca_power *bt_power;
@@ -604,7 +609,7 @@ static int qca_open(struct hci_uart *hu)
 	if (hu->serdev) {
 		qcadev = serdev_device_get_drvdata(hu->serdev);
 
-		if (qca_is_wcn399x(qcadev->btsoc_type))
+		if (qca_is_wcn399x_wcn6750(qcadev->btsoc_type))
 			hu->init_speed = qcadev->init_speed;
 
 		if (qcadev->oper_speed)
@@ -1308,7 +1313,7 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t baudrate)
 		      msecs_to_jiffies(CMD_TRANS_TIMEOUT_MS));
 
 	/* Give the controller time to process the request */
-	if (qca_is_wcn399x(qca_soc_type(hu)))
+	if (qca_is_wcn399x_wcn6750(qca_soc_type(hu)))
 		usleep_range(1000, 10000);
 	else
 		msleep(300);
@@ -1384,7 +1389,7 @@ static unsigned int qca_get_speed(struct hci_uart *hu,
 
 static int qca_check_speeds(struct hci_uart *hu)
 {
-	if (qca_is_wcn399x(qca_soc_type(hu))) {
+	if (qca_is_wcn399x_wcn6750(qca_soc_type(hu))) {
 		if (!qca_get_speed(hu, QCA_INIT_SPEED) &&
 		    !qca_get_speed(hu, QCA_OPER_SPEED))
 			return -EINVAL;
@@ -1417,7 +1422,7 @@ static int qca_set_speed(struct hci_uart *hu, enum qca_speed_type speed_type)
 		/* Disable flow control for wcn3990 to deassert RTS while
 		 * changing the baudrate of chip and host.
 		 */
-		if (qca_is_wcn399x(soc_type))
+		if (qca_is_wcn399x_wcn6750(soc_type))
 			hci_uart_set_flow_control(hu, true);
 
 		if (soc_type == QCA_WCN3990) {
@@ -1434,7 +1439,7 @@ static int qca_set_speed(struct hci_uart *hu, enum qca_speed_type speed_type)
 		host_set_baudrate(hu, speed);
 
 error:
-		if (qca_is_wcn399x(soc_type))
+		if (qca_is_wcn399x_wcn6750(soc_type))
 			hci_uart_set_flow_control(hu, false);
 
 		if (soc_type == QCA_WCN3990) {
@@ -1585,10 +1590,12 @@ static bool qca_prevent_wake(struct hci_dev *hdev)
 	return !wakeup;
 }
 
-static int qca_wcn3990_init(struct hci_uart *hu)
+static int qca_regulator_init(struct hci_uart *hu)
 {
+	enum qca_btsoc_type soc_type = qca_soc_type(hu);
 	struct qca_serdev *qcadev;
 	int ret;
+	bool sw_ctrl_state;
 
 	/* Check for vregs status, may be hci down has turned
 	 * off the voltage regulator.
@@ -1607,16 +1614,31 @@ static int qca_wcn3990_init(struct hci_uart *hu)
 		}
 	}
 
-	/* Forcefully enable wcn3990 to enter in to boot mode. */
-	host_set_baudrate(hu, 2400);
-	ret = qca_send_power_pulse(hu, false);
-	if (ret)
-		return ret;
+	if (qca_is_wcn399x(soc_type)) {
+		/* Forcefully enable wcn3990 to enter in to boot mode. */
+		host_set_baudrate(hu, 2400);
+		ret = qca_send_power_pulse(hu, false);
+		if (ret)
+			return ret;
+	}
+
+	/* For wcn6750 need to enable gpio bt_en */
+	if (qcadev->bt_en) {
+		gpiod_set_value_cansleep(qcadev->bt_en, BT_OFF);
+		msleep(50);
+		gpiod_set_value_cansleep(qcadev->bt_en, BT_ON);
+		msleep(50);
+		sw_ctrl_state = gpiod_get_value_cansleep(qcadev->sw_ctrl);
+		bt_dev_dbg(hu->hdev, "SW_CTRL is %d", sw_ctrl_state);
+	}
 
 	qca_set_speed(hu, QCA_INIT_SPEED);
-	ret = qca_send_power_pulse(hu, true);
-	if (ret)
-		return ret;
+
+	if (qca_is_wcn399x(soc_type)) {
+		ret = qca_send_power_pulse(hu, true);
+		if (ret)
+			return ret;
+	}
 
 	/* Now the device is in ready state to communicate with host.
 	 * To sync host with device we need to reopen port.
@@ -1649,12 +1671,12 @@ static int qca_power_on(struct hci_dev *hdev)
 	if (!hu->serdev)
 		return 0;
 
-	if (qca_is_wcn399x(soc_type)) {
-		ret = qca_wcn3990_init(hu);
+	if (qca_is_wcn399x_wcn6750(soc_type)) {
+		ret = qca_regulator_init(hu);
 	} else {
 		qcadev = serdev_device_get_drvdata(hu->serdev);
 		if (qcadev->bt_en) {
-			gpiod_set_value_cansleep(qcadev->bt_en, 1);
+			gpiod_set_value_cansleep(qcadev->bt_en, BT_ON);
 			/* Controller needs time to bootup. */
 			msleep(150);
 		}
@@ -1689,7 +1711,8 @@ static int qca_setup(struct hci_uart *hu)
 	set_bit(HCI_QUIRK_SIMULTANEOUS_DISCOVERY, &hdev->quirks);
 
 	bt_dev_info(hdev, "setting up %s",
-		qca_is_wcn399x(soc_type) ? "wcn399x" : "ROME/QCA6390");
+		qca_is_wcn399x(soc_type) ? "wcn399x" :
+		(soc_type == QCA_WCN6750) ? "wcn6750" : "ROME/QCA6390");
 
 	qca->memdump_state = QCA_MEMDUMP_IDLE;
 
@@ -1700,7 +1723,7 @@ static int qca_setup(struct hci_uart *hu)
 
 	clear_bit(QCA_SSR_TRIGGERED, &qca->flags);
 
-	if (qca_is_wcn399x(soc_type)) {
+	if (qca_is_wcn399x_wcn6750(soc_type)) {
 		set_bit(HCI_QUIRK_USE_BDADDR_PROPERTY, &hdev->quirks);
 
 		ret = qca_read_soc_version(hdev, &ver, soc_type);
@@ -1720,7 +1743,7 @@ static int qca_setup(struct hci_uart *hu)
 		qca_baudrate = qca_get_baudrate_value(speed);
 	}
 
-	if (!qca_is_wcn399x(soc_type)) {
+	if (!qca_is_wcn399x_wcn6750(soc_type)) {
 		/* Get QCA version information */
 		ret = qca_read_soc_version(hdev, &ver, soc_type);
 		if (ret)
@@ -1828,12 +1851,30 @@ static const struct qca_device_data qca_soc_data_qca6390 = {
 	.num_vregs = 0,
 };
 
+static const struct qca_device_data qca_soc_data_wcn6750 = {
+	.soc_type = QCA_WCN6750,
+	.vregs = (struct qca_vreg []) {
+		{ "vddio", 5000 },
+		{ "vddaon", 26000 },
+		{ "vddbtcxmx", 126000 },
+		{ "vddrfacmn", 12500 },
+		{ "vddrfa0p8", 102000 },
+		{ "vddrfa1p7", 302000 },
+		{ "vddrfa1p2", 257000 },
+		{ "vddrfa2p2", 1700000 },
+		{ "vddasd", 200 },
+	},
+	.num_vregs = 9,
+	.capabilities = QCA_CAP_WIDEBAND_SPEECH | QCA_CAP_VALID_LE_STATES,
+};
+
 static void qca_power_shutdown(struct hci_uart *hu)
 {
 	struct qca_serdev *qcadev;
 	struct qca_data *qca = hu->priv;
 	unsigned long flags;
 	enum qca_btsoc_type soc_type = qca_soc_type(hu);
+	bool sw_ctrl_state;
 
 	qcadev = serdev_device_get_drvdata(hu->serdev);
 
@@ -1856,8 +1897,14 @@ static void qca_power_shutdown(struct hci_uart *hu)
 		host_set_baudrate(hu, 2400);
 		qca_send_power_pulse(hu, false);
 		qca_regulator_disable(qcadev);
+	} else if (soc_type == QCA_WCN6750) {
+		gpiod_set_value_cansleep(qcadev->bt_en, BT_OFF);
+		msleep(100);
+		qca_regulator_disable(qcadev);
+		sw_ctrl_state = gpiod_get_value_cansleep(qcadev->sw_ctrl);
+		bt_dev_dbg(hu->hdev, "SW_CTRL is %d", sw_ctrl_state);
 	} else if (qcadev->bt_en) {
-		gpiod_set_value_cansleep(qcadev->bt_en, 0);
+		gpiod_set_value_cansleep(qcadev->bt_en, BT_OFF);
 	}
 
 	set_bit(QCA_BT_OFF, &qca->flags);
@@ -1978,7 +2025,7 @@ static int qca_serdev_probe(struct serdev_device *serdev)
 	if (!qcadev->oper_speed)
 		BT_DBG("UART will pick default operating speed");
 
-	if (data && qca_is_wcn399x(data->soc_type)) {
+	if (data && qca_is_wcn399x_wcn6750(data->soc_type)) {
 		qcadev->btsoc_type = data->soc_type;
 		qcadev->bt_power = devm_kzalloc(&serdev->dev,
 						sizeof(struct qca_power),
@@ -1996,6 +2043,18 @@ static int qca_serdev_probe(struct serdev_device *serdev)
 
 		qcadev->bt_power->vregs_on = false;
 
+		qcadev->bt_en = devm_gpiod_get_optional(&serdev->dev, "enable",
+					       GPIOD_OUT_LOW);
+		if (!qcadev->bt_en && data->soc_type == QCA_WCN6750) {
+			dev_err(&serdev->dev, "failed to acquire BT_EN gpio\n");
+			power_ctrl_enabled = false;
+		}
+
+		qcadev->sw_ctrl = devm_gpiod_get_optional(&serdev->dev, "swctrl",
+					       GPIOD_IN);
+		if (!qcadev->sw_ctrl && data->soc_type == QCA_WCN6750)
+			dev_warn(&serdev->dev, "failed to acquire SW_CTRL gpio\n");
+
 		qcadev->susclk = devm_clk_get_optional(&serdev->dev, NULL);
 		if (IS_ERR(qcadev->susclk)) {
 			dev_err(&serdev->dev, "failed to acquire clk\n");
@@ -2068,7 +2127,7 @@ static void qca_serdev_remove(struct serdev_device *serdev)
 	struct qca_serdev *qcadev = serdev_device_get_drvdata(serdev);
 	struct qca_power *power = qcadev->bt_power;
 
-	if (qca_is_wcn399x(qcadev->btsoc_type) && power->vregs_on)
+	if (qca_is_wcn399x_wcn6750(qcadev->btsoc_type) && power->vregs_on)
 		qca_power_shutdown(&qcadev->serdev_hu);
 	else if (qcadev->susclk)
 		clk_disable_unprepare(qcadev->susclk);
@@ -2244,6 +2303,7 @@ static const struct of_device_id qca_bluetooth_of_match[] = {
 	{ .compatible = "qcom,wcn3990-bt", .data = &qca_soc_data_wcn3990},
 	{ .compatible = "qcom,wcn3991-bt", .data = &qca_soc_data_wcn3991},
 	{ .compatible = "qcom,wcn3998-bt", .data = &qca_soc_data_wcn3998},
+	{ .compatible = "qcom,wcn6750-bt", .data = &qca_soc_data_wcn6750},
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, qca_bluetooth_of_match);
-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member 
of Code Aurora Forum, hosted by The Linux Foundation




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