Bluetooth: btmtkuart: add an implementation for clock osc property

Some board requires explicitily control external osscilator via GPIO.
So, add an implementation of a clock property for an external oscillator
to the device.

Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

1 files changed, 18 insertions, 3 deletions

diff --git a/drivers/bluetooth/btmtkuart.c b/drivers/bluetooth/btmtkuart.c
index 1257149cfdc4..e11169ad8247 100644
--- a/drivers/bluetooth/btmtkuart.c
+++ b/drivers/bluetooth/btmtkuart.c
@@ -115,8 +115,9 @@ struct btmtk_hci_wmt_params {
 struct btmtkuart_dev {
         struct hci_dev *hdev;
         struct serdev_device *serdev;
-        struct clk *clk;
 
+        struct clk *clk;
+        struct clk *osc;
         struct regulator *vcc;
         struct gpio_desc *reset;
         struct gpio_desc *boot;
@@ -912,6 +913,12 @@ static int btmtkuart_parse_dt(struct serdev_device *serdev)
                         return err;
                 }
 
+                bdev->osc = devm_clk_get_optional(&serdev->dev, "osc");
+                if (IS_ERR(bdev->osc)) {
+                        err = PTR_ERR(bdev->osc);
+                        return err;
+                }
+
                 bdev->boot = devm_gpiod_get_optional(&serdev->dev, "boot",
                                                      GPIOD_OUT_LOW);
                 if (IS_ERR(bdev->boot)) {
@@ -1006,6 +1013,10 @@ static int btmtkuart_probe(struct serdev_device *serdev)
         set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks);
 
         if (btmtkuart_is_standalone(bdev)) {
+                err = clk_prepare_enable(bdev->osc);
+                if (err < 0)
+                        return err;
+
                 if (bdev->boot) {
                         gpiod_set_value_cansleep(bdev->boot, 1);
                 } else {
@@ -1017,8 +1028,10 @@ static int btmtkuart_probe(struct serdev_device *serdev)
 
                 /* Power on */
                 err = regulator_enable(bdev->vcc);
-                if (err < 0)
+                if (err < 0) {
+                        clk_disable_unprepare(bdev->osc);
                         return err;
+                }
 
                 /* Reset if the reset-gpios is available otherwise the board
                  * -level design should be guaranteed.
@@ -1068,8 +1081,10 @@ static void btmtkuart_remove(struct serdev_device *serdev)
         struct btmtkuart_dev *bdev = serdev_device_get_drvdata(serdev);
         struct hci_dev *hdev = bdev->hdev;
 
-        if (btmtkuart_is_standalone(bdev))
+        if (btmtkuart_is_standalone(bdev)) {
                 regulator_disable(bdev->vcc);
+                clk_disable_unprepare(bdev->osc);
+        }
 
         hci_unregister_dev(hdev);
         hci_free_dev(hdev);