[PATCH v4 2/3] usb: dwc3: add optional PHY interface clocks

Sebastian Reichel sebastian.reichel at collabora.com
Fri Oct 20 07:11:41 PDT 2023


On Rockchip RK3588 one of the DWC3 cores is integrated weirdly and
requires two extra clocks to be enabled. Without these extra clocks
hot-plugging USB devices is broken.

Signed-off-by: Sebastian Reichel <sebastian.reichel at collabora.com>
---
 drivers/usb/dwc3/core.c | 28 ++++++++++++++++++++++++++++
 drivers/usb/dwc3/core.h |  4 ++++
 2 files changed, 32 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 343d2570189f..639b768c3386 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -854,8 +854,20 @@ static int dwc3_clk_enable(struct dwc3 *dwc)
 	if (ret)
 		goto disable_ref_clk;
 
+	ret = clk_prepare_enable(dwc->utmi_clk);
+	if (ret)
+		goto disable_susp_clk;
+
+	ret = clk_prepare_enable(dwc->pipe_clk);
+	if (ret)
+		goto disable_utmi_clk;
+
 	return 0;
 
+disable_utmi_clk:
+	clk_disable_unprepare(dwc->utmi_clk);
+disable_susp_clk:
+	clk_disable_unprepare(dwc->susp_clk);
 disable_ref_clk:
 	clk_disable_unprepare(dwc->ref_clk);
 disable_bus_clk:
@@ -865,6 +877,8 @@ static int dwc3_clk_enable(struct dwc3 *dwc)
 
 static void dwc3_clk_disable(struct dwc3 *dwc)
 {
+	clk_disable_unprepare(dwc->pipe_clk);
+	clk_disable_unprepare(dwc->utmi_clk);
 	clk_disable_unprepare(dwc->susp_clk);
 	clk_disable_unprepare(dwc->ref_clk);
 	clk_disable_unprepare(dwc->bus_clk);
@@ -1785,6 +1799,20 @@ static int dwc3_get_clocks(struct dwc3 *dwc)
 		}
 	}
 
+	/* specific to Rockchip RK3588 */
+	dwc->utmi_clk = devm_clk_get_optional(dev, "utmi");
+	if (IS_ERR(dwc->utmi_clk)) {
+		return dev_err_probe(dev, PTR_ERR(dwc->utmi_clk),
+				"could not get utmi clock\n");
+	}
+
+	/* specific to Rockchip RK3588 */
+	dwc->pipe_clk = devm_clk_get_optional(dev, "pipe");
+	if (IS_ERR(dwc->pipe_clk)) {
+		return dev_err_probe(dev, PTR_ERR(dwc->pipe_clk),
+				"could not get pipe clock\n");
+	}
+
 	return 0;
 }
 
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index a69ac67d89fe..f5e6ae6e394e 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -991,6 +991,8 @@ struct dwc3_scratchpad_array {
  * @bus_clk: clock for accessing the registers
  * @ref_clk: reference clock
  * @susp_clk: clock used when the SS phy is in low power (S3) state
+ * @utmi_clk: clock used for USB2 PHY communication
+ * @pipe_clk: clock used for USB3 PHY communication
  * @reset: reset control
  * @regs: base address for our registers
  * @regs_size: address space size
@@ -1156,6 +1158,8 @@ struct dwc3 {
 	struct clk		*bus_clk;
 	struct clk		*ref_clk;
 	struct clk		*susp_clk;
+	struct clk		*utmi_clk;
+	struct clk		*pipe_clk;
 
 	struct reset_control	*reset;
 
-- 
2.42.0




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