[PATCH v7 4/4] Bluetooth: hci_qca: Add serdev support

[Thierry Escande]

Add support for Qualcomm serial slave devices. Probe the serial device,
retrieve its maximum speed and register a new hci uart device.

Signed-off-by: Thierry Escande 
Reviewed-by: Andy Shevchenko 
---

v7: no change

v6:
- Fix gpio name in error message

v5:
- Use gpio new name 'enable'

v4:
- Rename divclk4 as susclk (its name in the bt chip)
- Use gpiod_set_value_cansleep()
- Replace #include  with 
- Restore dependency on BT_HCIUART

v3:
- Remove redundant call to gpiod_set_value() after devm_gpiod_get()
- Check returned values for clk_set_rate() and clk_prepare_enable()
- Use clk_disable_unprepare()

v2:
- Fix author email

 drivers/bluetooth/Kconfig   |   1 +
 drivers/bluetooth/hci_qca.c | 110 +++-
 2 files changed, 109 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
index 07e55cd8f8c8..e0f1a6609b68 100644
--- a/drivers/bluetooth/Kconfig
+++ b/drivers/bluetooth/Kconfig
@@ -196,6 +196,7 @@ config BT_HCIUART_BCM
 config BT_HCIUART_QCA
bool "Qualcomm Atheros protocol support"
depends on BT_HCIUART
+   depends on BT_HCIUART_SERDEV
select BT_HCIUART_H4
select BT_QCA
help
diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index 05ec530b8a3a..1afa17ff6303 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -29,7 +29,12 @@
  */
 
 #include 
+#include 
 #include 
+#include 
+#include 
+#include 
+#include 
 
 #include 
 #include 
@@ -50,6 +55,9 @@
 #define IBS_TX_IDLE_TIMEOUT_MS 2000
 #define BAUDRATE_SETTLE_TIMEOUT_MS 300
 
+/* susclk rate */
+#define SUSCLK_RATE_32KHZ  32768
+
 /* HCI_IBS transmit side sleep protocol states */
 enum tx_ibs_states {
HCI_IBS_TX_ASLEEP,
@@ -111,6 +119,12 @@ struct qca_data {
u64 votes_off;
 };
 
+struct qca_serdev {
+   struct hci_uart  serdev_hu;
+   struct gpio_desc *bt_en;
+   struct clk   *susclk;
+};
+
 static void __serial_clock_on(struct tty_struct *tty)
 {
/* TODO: Some chipset requires to enable UART clock on client
@@ -386,6 +400,7 @@ static void hci_ibs_wake_retrans_timeout(struct timer_list 
*t)
 /* Initialize protocol */
 static int qca_open(struct hci_uart *hu)
 {
+   struct qca_serdev *qcadev;
struct qca_data *qca;
 
BT_DBG("hu %p qca_open", hu);
@@ -444,6 +459,13 @@ static int qca_open(struct hci_uart *hu)
timer_setup(>tx_idle_timer, hci_ibs_tx_idle_timeout, 0);
qca->tx_idle_delay = IBS_TX_IDLE_TIMEOUT_MS;
 
+   if (hu->serdev) {
+   serdev_device_open(hu->serdev);
+
+   qcadev = serdev_device_get_drvdata(hu->serdev);
+   gpiod_set_value_cansleep(qcadev->bt_en, 1);
+   }
+
BT_DBG("HCI_UART_QCA open, tx_idle_delay=%u, wake_retrans=%u",
   qca->tx_idle_delay, qca->wake_retrans);
 
@@ -512,6 +534,7 @@ static int qca_flush(struct hci_uart *hu)
 /* Close protocol */
 static int qca_close(struct hci_uart *hu)
 {
+   struct qca_serdev *qcadev;
struct qca_data *qca = hu->priv;
 
BT_DBG("hu %p qca close", hu);
@@ -525,6 +548,13 @@ static int qca_close(struct hci_uart *hu)
destroy_workqueue(qca->workqueue);
qca->hu = NULL;
 
+   if (hu->serdev) {
+   serdev_device_close(hu->serdev);
+
+   qcadev = serdev_device_get_drvdata(hu->serdev);
+   gpiod_set_value_cansleep(qcadev->bt_en, 0);
+   }
+
kfree_skb(qca->rx_skb);
 
hu->priv = NULL;
@@ -885,6 +915,14 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t 
baudrate)
return 0;
 }
 
+static inline void host_set_baudrate(struct hci_uart *hu, unsigned int speed)
+{
+   if (hu->serdev)
+   serdev_device_set_baudrate(hu->serdev, speed);
+   else
+   hci_uart_set_baudrate(hu, speed);
+}
+
 static int qca_setup(struct hci_uart *hu)
 {
struct hci_dev *hdev = hu->hdev;
@@ -905,7 +943,7 @@ static int qca_setup(struct hci_uart *hu)
speed = hu->proto->init_speed;
 
if (speed)
-   hci_uart_set_baudrate(hu, speed);
+   host_set_baudrate(hu, speed);
 
/* Setup user speed if needed */
speed = 0;
@@ -924,7 +962,7 @@ static int qca_setup(struct hci_uart *hu)
   ret);
return ret;
}
-   hci_uart_set_baudrate(hu, speed);
+   host_set_baudrate(hu, speed);
}
 
/* Setup patch / NVM configurations */
@@ -958,12 +996,80 @@ static struct hci_uart_proto qca_proto = {
.dequeue= qca_dequeue,
 };
 
+static int qca_serdev_probe(struct serdev_device *serdev)
+{
+   struct qca_serdev *qcadev;
+   int err;
+
+   qcadev = devm_kzalloc(>dev, sizeof(*qcadev), GFP_KERNEL);
+   if (!qcadev)
+   return 

[PATCH v7 4/4] Bluetooth: hci_qca: Add serdev support

[Thierry Escande]

Add support for Qualcomm serial slave devices. Probe the serial device,
retrieve its maximum speed and register a new hci uart device.

Signed-off-by: Thierry Escande 
Reviewed-by: Andy Shevchenko 
---

v7: no change

v6:
- Fix gpio name in error message

v5:
- Use gpio new name 'enable'

v4:
- Rename divclk4 as susclk (its name in the bt chip)
- Use gpiod_set_value_cansleep()
- Replace #include  with 
- Restore dependency on BT_HCIUART

v3:
- Remove redundant call to gpiod_set_value() after devm_gpiod_get()
- Check returned values for clk_set_rate() and clk_prepare_enable()
- Use clk_disable_unprepare()

v2:
- Fix author email

 drivers/bluetooth/Kconfig   |   1 +
 drivers/bluetooth/hci_qca.c | 110 +++-
 2 files changed, 109 insertions(+), 2 deletions(-)

diff --git a/drivers/bluetooth/Kconfig b/drivers/bluetooth/Kconfig
index 07e55cd8f8c8..e0f1a6609b68 100644
--- a/drivers/bluetooth/Kconfig
+++ b/drivers/bluetooth/Kconfig
@@ -196,6 +196,7 @@ config BT_HCIUART_BCM
 config BT_HCIUART_QCA
bool "Qualcomm Atheros protocol support"
depends on BT_HCIUART
+   depends on BT_HCIUART_SERDEV
select BT_HCIUART_H4
select BT_QCA
help
diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index 05ec530b8a3a..1afa17ff6303 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -29,7 +29,12 @@
  */
 
 #include 
+#include 
 #include 
+#include 
+#include 
+#include 
+#include 
 
 #include 
 #include 
@@ -50,6 +55,9 @@
 #define IBS_TX_IDLE_TIMEOUT_MS 2000
 #define BAUDRATE_SETTLE_TIMEOUT_MS 300
 
+/* susclk rate */
+#define SUSCLK_RATE_32KHZ  32768
+
 /* HCI_IBS transmit side sleep protocol states */
 enum tx_ibs_states {
HCI_IBS_TX_ASLEEP,
@@ -111,6 +119,12 @@ struct qca_data {
u64 votes_off;
 };
 
+struct qca_serdev {
+   struct hci_uart  serdev_hu;
+   struct gpio_desc *bt_en;
+   struct clk   *susclk;
+};
+
 static void __serial_clock_on(struct tty_struct *tty)
 {
/* TODO: Some chipset requires to enable UART clock on client
@@ -386,6 +400,7 @@ static void hci_ibs_wake_retrans_timeout(struct timer_list 
*t)
 /* Initialize protocol */
 static int qca_open(struct hci_uart *hu)
 {
+   struct qca_serdev *qcadev;
struct qca_data *qca;
 
BT_DBG("hu %p qca_open", hu);
@@ -444,6 +459,13 @@ static int qca_open(struct hci_uart *hu)
timer_setup(>tx_idle_timer, hci_ibs_tx_idle_timeout, 0);
qca->tx_idle_delay = IBS_TX_IDLE_TIMEOUT_MS;
 
+   if (hu->serdev) {
+   serdev_device_open(hu->serdev);
+
+   qcadev = serdev_device_get_drvdata(hu->serdev);
+   gpiod_set_value_cansleep(qcadev->bt_en, 1);
+   }
+
BT_DBG("HCI_UART_QCA open, tx_idle_delay=%u, wake_retrans=%u",
   qca->tx_idle_delay, qca->wake_retrans);
 
@@ -512,6 +534,7 @@ static int qca_flush(struct hci_uart *hu)
 /* Close protocol */
 static int qca_close(struct hci_uart *hu)
 {
+   struct qca_serdev *qcadev;
struct qca_data *qca = hu->priv;
 
BT_DBG("hu %p qca close", hu);
@@ -525,6 +548,13 @@ static int qca_close(struct hci_uart *hu)
destroy_workqueue(qca->workqueue);
qca->hu = NULL;
 
+   if (hu->serdev) {
+   serdev_device_close(hu->serdev);
+
+   qcadev = serdev_device_get_drvdata(hu->serdev);
+   gpiod_set_value_cansleep(qcadev->bt_en, 0);
+   }
+
kfree_skb(qca->rx_skb);
 
hu->priv = NULL;
@@ -885,6 +915,14 @@ static int qca_set_baudrate(struct hci_dev *hdev, uint8_t 
baudrate)
return 0;
 }
 
+static inline void host_set_baudrate(struct hci_uart *hu, unsigned int speed)
+{
+   if (hu->serdev)
+   serdev_device_set_baudrate(hu->serdev, speed);
+   else
+   hci_uart_set_baudrate(hu, speed);
+}
+
 static int qca_setup(struct hci_uart *hu)
 {
struct hci_dev *hdev = hu->hdev;
@@ -905,7 +943,7 @@ static int qca_setup(struct hci_uart *hu)
speed = hu->proto->init_speed;
 
if (speed)
-   hci_uart_set_baudrate(hu, speed);
+   host_set_baudrate(hu, speed);
 
/* Setup user speed if needed */
speed = 0;
@@ -924,7 +962,7 @@ static int qca_setup(struct hci_uart *hu)
   ret);
return ret;
}
-   hci_uart_set_baudrate(hu, speed);
+   host_set_baudrate(hu, speed);
}
 
/* Setup patch / NVM configurations */
@@ -958,12 +996,80 @@ static struct hci_uart_proto qca_proto = {
.dequeue= qca_dequeue,
 };
 
+static int qca_serdev_probe(struct serdev_device *serdev)
+{
+   struct qca_serdev *qcadev;
+   int err;
+
+   qcadev = devm_kzalloc(>dev, sizeof(*qcadev), GFP_KERNEL);
+   if (!qcadev)
+   return -ENOMEM;
+
+   qcadev->serdev_hu.serdev = serdev;
+