[PATCH v2 03/22] usb: dwc3: glue: Allow more fine grained control over mode switches

[Sven Peter <sven@kernel.org>]

We need fine grained control over mode switched on the DWC3 controller
present on Apple Silicon. Export core, host and gadget init and exit,
ptrcap and susphy control functions. Also introduce an additional
parameter to probe_data that allows to skip the final initialization
step that would bring up host or gadget mode.

Signed-off-by: Sven Peter <sven@kernel.org>
---
 drivers/usb/dwc3/core.c   | 16 +++++++++++-----
 drivers/usb/dwc3/gadget.c |  2 ++
 drivers/usb/dwc3/glue.h   | 14 ++++++++++++++
 drivers/usb/dwc3/host.c   |  2 ++
 4 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 8002c23a5a02acb8f3e87b2662a53998a4cf4f5c..18056fac44c8732278a650ac2be8b493892c92dd 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -132,6 +132,7 @@ void dwc3_enable_susphy(struct dwc3 *dwc, bool enable)
 		dwc3_writel(dwc->regs, DWC3_GUSB2PHYCFG(i), reg);
 	}
 }
+EXPORT_SYMBOL_GPL(dwc3_enable_susphy);
 
 void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode, bool ignore_susphy)
 {
@@ -157,6 +158,7 @@ void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode, bool ignore_susphy)
 
 	dwc->current_dr_role = mode;
 }
+EXPORT_SYMBOL_GPL(dwc3_set_prtcap);
 
 static void __dwc3_set_mode(struct work_struct *work)
 {
@@ -974,7 +976,7 @@ static void dwc3_clk_disable(struct dwc3 *dwc)
 	clk_disable_unprepare(dwc->bus_clk);
 }
 
-static void dwc3_core_exit(struct dwc3 *dwc)
+void dwc3_core_exit(struct dwc3 *dwc)
 {
 	dwc3_event_buffers_cleanup(dwc);
 	dwc3_phy_power_off(dwc);
@@ -982,6 +984,7 @@ static void dwc3_core_exit(struct dwc3 *dwc)
 	dwc3_clk_disable(dwc);
 	reset_control_assert(dwc->reset);
 }
+EXPORT_SYMBOL_GPL(dwc3_core_exit);
 
 static bool dwc3_core_is_valid(struct dwc3 *dwc)
 {
@@ -1327,7 +1330,7 @@ static void dwc3_config_threshold(struct dwc3 *dwc)
  *
  * Returns 0 on success otherwise negative errno.
  */
-static int dwc3_core_init(struct dwc3 *dwc)
+int dwc3_core_init(struct dwc3 *dwc)
 {
 	unsigned int		hw_mode;
 	u32			reg;
@@ -1527,6 +1530,7 @@ static int dwc3_core_init(struct dwc3 *dwc)
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(dwc3_core_init);
 
 static int dwc3_core_get_phy(struct dwc3 *dwc)
 {
@@ -2298,9 +2302,11 @@ int dwc3_core_probe(const struct dwc3_probe_data *data)
 	dwc3_check_params(dwc);
 	dwc3_debugfs_init(dwc);
 
-	ret = dwc3_core_init_mode(dwc);
-	if (ret)
-		goto err_exit_debugfs;
+	if (!data->skip_core_init_mode) {
+		ret = dwc3_core_init_mode(dwc);
+		if (ret)
+			goto err_exit_debugfs;
+	}
 
 	pm_runtime_put(dev);
 
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 25db36c63951bf5654f4bf5a98d7073a028364cd..7b92eb8c4ccf118b81f27afaf3f31bf56e1b6f74 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -4794,6 +4794,7 @@ int dwc3_gadget_init(struct dwc3 *dwc)
 err0:
 	return ret;
 }
+EXPORT_SYMBOL_GPL(dwc3_gadget_init);
 
 /* -------------------------------------------------------------------------- */
 
@@ -4812,6 +4813,7 @@ void dwc3_gadget_exit(struct dwc3 *dwc)
 	dma_free_coherent(dwc->sysdev, sizeof(*dwc->ep0_trb) * 2,
 			  dwc->ep0_trb, dwc->ep0_trb_addr);
 }
+EXPORT_SYMBOL_GPL(dwc3_gadget_exit);
 
 int dwc3_gadget_suspend(struct dwc3 *dwc)
 {
diff --git a/drivers/usb/dwc3/glue.h b/drivers/usb/dwc3/glue.h
index 2efd00e763be4fc51911f32d43054059e61fb43a..633268c76fe4c7fdc312c9705dfa7cf7ccf3544c 100644
--- a/drivers/usb/dwc3/glue.h
+++ b/drivers/usb/dwc3/glue.h
@@ -15,16 +15,30 @@
  * @res: resource for the DWC3 core mmio region
  * @ignore_clocks_and_resets: clocks and resets defined for the device should
  *		be ignored by the DWC3 core, as they are managed by the glue
+ * @skip_core_init_mode: skip the finial initialization of the target mode, as
+ *		it must be managed by the glue
  */
 struct dwc3_probe_data {
 	struct dwc3 *dwc;
 	struct resource *res;
 	bool ignore_clocks_and_resets;
+	bool skip_core_init_mode;
 };
 
 int dwc3_core_probe(const struct dwc3_probe_data *data);
 void dwc3_core_remove(struct dwc3 *dwc);
 
+int dwc3_core_init(struct dwc3 *dwc);
+void dwc3_core_exit(struct dwc3 *dwc);
+
+int dwc3_host_init(struct dwc3 *dwc);
+void dwc3_host_exit(struct dwc3 *dwc);
+int dwc3_gadget_init(struct dwc3 *dwc);
+void dwc3_gadget_exit(struct dwc3 *dwc);
+
+void dwc3_enable_susphy(struct dwc3 *dwc, bool enable);
+void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode, bool ignore_susphy);
+
 int dwc3_runtime_suspend(struct dwc3 *dwc);
 int dwc3_runtime_resume(struct dwc3 *dwc);
 int dwc3_runtime_idle(struct dwc3 *dwc);
diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
index e77fd86d09cf0a36161c20ad3c83f10e67099775..cf6512ed17a69134e6ca1b884f76c1439693fab1 100644
--- a/drivers/usb/dwc3/host.c
+++ b/drivers/usb/dwc3/host.c
@@ -220,6 +220,7 @@ int dwc3_host_init(struct dwc3 *dwc)
 	platform_device_put(xhci);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(dwc3_host_init);
 
 void dwc3_host_exit(struct dwc3 *dwc)
 {
@@ -230,3 +231,4 @@ void dwc3_host_exit(struct dwc3 *dwc)
 	platform_device_unregister(dwc->xhci);
 	dwc->xhci = NULL;
 }
+EXPORT_SYMBOL_GPL(dwc3_host_exit);

-- 
2.34.1