[PATCH v2 1/2] Bluetooth: hci_qca: Enable clocks required for BT SOC

From: Venkata Lakshmi Narayana Gubba
Date: Fri Jan 31 2020 - 02:39:42 EST


Instead of relying on other subsytem to turn ON clocks
required for BT SoC to operate, voting them from the driver.

Signed-off-by: Venkata Lakshmi Narayana Gubba <gubbaven@xxxxxxxxxxxxxx>
---
v2:
* addressed forward declarations
* updated with devm_clk_get_optional()

---
drivers/bluetooth/hci_qca.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index d6e0c99..73706f3 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -1738,6 +1738,15 @@ static int qca_power_off(struct hci_dev *hdev)
return 0;
}

+static int qca_setup_clock(struct clk *clk, bool enable)
+{
+ if (enable)
+ return clk_prepare_enable(clk);
+
+ clk_disable_unprepare(clk);
+ return 0;
+}
+
static int qca_regulator_enable(struct qca_serdev *qcadev)
{
struct qca_power *power = qcadev->bt_power;
@@ -1755,6 +1764,13 @@ static int qca_regulator_enable(struct qca_serdev *qcadev)

power->vregs_on = true;

+ ret = qca_setup_clock(qcadev->susclk, true);
+ if (ret) {
+ /* Turn off regulators to overcome power leakage */
+ qca_regulator_disable(qcadev);
+ return ret;
+ }
+
return 0;
}

@@ -1773,6 +1789,9 @@ static void qca_regulator_disable(struct qca_serdev *qcadev)

regulator_bulk_disable(power->num_vregs, power->vreg_bulk);
power->vregs_on = false;
+
+ if (qcadev->susclk)
+ qca_setup_clock(qcadev->susclk, false);
}

static int qca_init_regulators(struct qca_power *qca,
@@ -1839,6 +1858,12 @@ static int qca_serdev_probe(struct serdev_device *serdev)

qcadev->bt_power->vregs_on = false;

+ qcadev->susclk = devm_clk_get_optional(&serdev->dev, NULL);
+ if (IS_ERR(qcadev->susclk)) {
+ dev_err(&serdev->dev, "failed to acquire clk\n");
+ return PTR_ERR(qcadev->susclk);
+ }
+
device_property_read_u32(&serdev->dev, "max-speed",
&qcadev->oper_speed);
if (!qcadev->oper_speed)
--
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