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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/dwc2/drd.c
parentInitial commit. (diff)
downloadlinux-upstream.tar.xz
linux-upstream.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/dwc2/drd.c')
-rw-r--r--drivers/usb/dwc2/drd.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/drivers/usb/dwc2/drd.c b/drivers/usb/dwc2/drd.c
new file mode 100644
index 000000000..a8605b021
--- /dev/null
+++ b/drivers/usb/dwc2/drd.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * drd.c - DesignWare USB2 DRD Controller Dual-role support
+ *
+ * Copyright (C) 2020 STMicroelectronics
+ *
+ * Author(s): Amelie Delaunay <amelie.delaunay@st.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <linux/platform_device.h>
+#include <linux/usb/role.h>
+#include "core.h"
+
+#define dwc2_ovr_gotgctl(gotgctl) \
+ ((gotgctl) |= GOTGCTL_BVALOEN | GOTGCTL_AVALOEN | GOTGCTL_VBVALOEN | \
+ GOTGCTL_DBNCE_FLTR_BYPASS)
+
+static void dwc2_ovr_init(struct dwc2_hsotg *hsotg)
+{
+ unsigned long flags;
+ u32 gotgctl;
+
+ spin_lock_irqsave(&hsotg->lock, flags);
+
+ gotgctl = dwc2_readl(hsotg, GOTGCTL);
+ dwc2_ovr_gotgctl(gotgctl);
+ gotgctl &= ~(GOTGCTL_BVALOVAL | GOTGCTL_AVALOVAL | GOTGCTL_VBVALOVAL);
+ if (hsotg->role_sw_default_mode == USB_DR_MODE_HOST)
+ gotgctl |= GOTGCTL_AVALOVAL | GOTGCTL_VBVALOVAL;
+ else if (hsotg->role_sw_default_mode == USB_DR_MODE_PERIPHERAL)
+ gotgctl |= GOTGCTL_BVALOVAL | GOTGCTL_VBVALOVAL;
+ dwc2_writel(hsotg, gotgctl, GOTGCTL);
+
+ spin_unlock_irqrestore(&hsotg->lock, flags);
+
+ dwc2_force_mode(hsotg, (hsotg->dr_mode == USB_DR_MODE_HOST) ||
+ (hsotg->role_sw_default_mode == USB_DR_MODE_HOST));
+}
+
+static int dwc2_ovr_avalid(struct dwc2_hsotg *hsotg, bool valid)
+{
+ u32 gotgctl = dwc2_readl(hsotg, GOTGCTL);
+
+ /* Check if A-Session is already in the right state */
+ if ((valid && (gotgctl & GOTGCTL_ASESVLD)) ||
+ (!valid && !(gotgctl & GOTGCTL_ASESVLD)))
+ return -EALREADY;
+
+ /* Always enable overrides to handle the resume case */
+ dwc2_ovr_gotgctl(gotgctl);
+
+ gotgctl &= ~GOTGCTL_BVALOVAL;
+ if (valid)
+ gotgctl |= GOTGCTL_AVALOVAL | GOTGCTL_VBVALOVAL;
+ else
+ gotgctl &= ~(GOTGCTL_AVALOVAL | GOTGCTL_VBVALOVAL);
+ dwc2_writel(hsotg, gotgctl, GOTGCTL);
+
+ return 0;
+}
+
+static int dwc2_ovr_bvalid(struct dwc2_hsotg *hsotg, bool valid)
+{
+ u32 gotgctl = dwc2_readl(hsotg, GOTGCTL);
+
+ /* Check if B-Session is already in the right state */
+ if ((valid && (gotgctl & GOTGCTL_BSESVLD)) ||
+ (!valid && !(gotgctl & GOTGCTL_BSESVLD)))
+ return -EALREADY;
+
+ /* Always enable overrides to handle the resume case */
+ dwc2_ovr_gotgctl(gotgctl);
+
+ gotgctl &= ~GOTGCTL_AVALOVAL;
+ if (valid)
+ gotgctl |= GOTGCTL_BVALOVAL | GOTGCTL_VBVALOVAL;
+ else
+ gotgctl &= ~(GOTGCTL_BVALOVAL | GOTGCTL_VBVALOVAL);
+ dwc2_writel(hsotg, gotgctl, GOTGCTL);
+
+ return 0;
+}
+
+static int dwc2_drd_role_sw_set(struct usb_role_switch *sw, enum usb_role role)
+{
+ struct dwc2_hsotg *hsotg = usb_role_switch_get_drvdata(sw);
+ unsigned long flags;
+ int already = 0;
+
+ /* Skip session not in line with dr_mode */
+ if ((role == USB_ROLE_DEVICE && hsotg->dr_mode == USB_DR_MODE_HOST) ||
+ (role == USB_ROLE_HOST && hsotg->dr_mode == USB_DR_MODE_PERIPHERAL))
+ return -EINVAL;
+
+#if IS_ENABLED(CONFIG_USB_DWC2_PERIPHERAL) || \
+ IS_ENABLED(CONFIG_USB_DWC2_DUAL_ROLE)
+ /* Skip session if core is in test mode */
+ if (role == USB_ROLE_NONE && hsotg->test_mode) {
+ dev_dbg(hsotg->dev, "Core is in test mode\n");
+ return -EBUSY;
+ }
+#endif
+
+ /*
+ * In case of USB_DR_MODE_PERIPHERAL, clock is disabled at the end of
+ * the probe and enabled on udc_start.
+ * If role-switch set is called before the udc_start, we need to enable
+ * the clock to read/write GOTGCTL and GUSBCFG registers to override
+ * mode and sessions. It is the case if cable is plugged at boot.
+ */
+ if (!hsotg->ll_hw_enabled && hsotg->clk) {
+ int ret = clk_prepare_enable(hsotg->clk);
+
+ if (ret)
+ return ret;
+ }
+
+ spin_lock_irqsave(&hsotg->lock, flags);
+
+ if (role == USB_ROLE_NONE) {
+ /* default operation mode when usb role is USB_ROLE_NONE */
+ if (hsotg->role_sw_default_mode == USB_DR_MODE_HOST)
+ role = USB_ROLE_HOST;
+ else if (hsotg->role_sw_default_mode == USB_DR_MODE_PERIPHERAL)
+ role = USB_ROLE_DEVICE;
+ }
+
+ if (role == USB_ROLE_HOST) {
+ already = dwc2_ovr_avalid(hsotg, true);
+ } else if (role == USB_ROLE_DEVICE) {
+ already = dwc2_ovr_bvalid(hsotg, true);
+ if (dwc2_is_device_enabled(hsotg)) {
+ /* This clear DCTL.SFTDISCON bit */
+ dwc2_hsotg_core_connect(hsotg);
+ }
+ } else {
+ if (dwc2_is_device_mode(hsotg)) {
+ if (!dwc2_ovr_bvalid(hsotg, false))
+ /* This set DCTL.SFTDISCON bit */
+ dwc2_hsotg_core_disconnect(hsotg);
+ } else {
+ dwc2_ovr_avalid(hsotg, false);
+ }
+ }
+
+ spin_unlock_irqrestore(&hsotg->lock, flags);
+
+ if (!already && hsotg->dr_mode == USB_DR_MODE_OTG)
+ /* This will raise a Connector ID Status Change Interrupt */
+ dwc2_force_mode(hsotg, role == USB_ROLE_HOST);
+
+ if (!hsotg->ll_hw_enabled && hsotg->clk)
+ clk_disable_unprepare(hsotg->clk);
+
+ dev_dbg(hsotg->dev, "%s-session valid\n",
+ role == USB_ROLE_NONE ? "No" :
+ role == USB_ROLE_HOST ? "A" : "B");
+
+ return 0;
+}
+
+int dwc2_drd_init(struct dwc2_hsotg *hsotg)
+{
+ struct usb_role_switch_desc role_sw_desc = {0};
+ struct usb_role_switch *role_sw;
+ int ret;
+
+ if (!device_property_read_bool(hsotg->dev, "usb-role-switch"))
+ return 0;
+
+ hsotg->role_sw_default_mode = usb_get_role_switch_default_mode(hsotg->dev);
+ role_sw_desc.driver_data = hsotg;
+ role_sw_desc.fwnode = dev_fwnode(hsotg->dev);
+ role_sw_desc.set = dwc2_drd_role_sw_set;
+ role_sw_desc.allow_userspace_control = true;
+
+ role_sw = usb_role_switch_register(hsotg->dev, &role_sw_desc);
+ if (IS_ERR(role_sw)) {
+ ret = PTR_ERR(role_sw);
+ dev_err(hsotg->dev,
+ "failed to register role switch: %d\n", ret);
+ return ret;
+ }
+
+ hsotg->role_sw = role_sw;
+
+ /* Enable override and initialize values */
+ dwc2_ovr_init(hsotg);
+
+ return 0;
+}
+
+void dwc2_drd_suspend(struct dwc2_hsotg *hsotg)
+{
+ u32 gintsts, gintmsk;
+
+ if (hsotg->role_sw && !hsotg->params.external_id_pin_ctl) {
+ gintmsk = dwc2_readl(hsotg, GINTMSK);
+ gintmsk &= ~GINTSTS_CONIDSTSCHNG;
+ dwc2_writel(hsotg, gintmsk, GINTMSK);
+ gintsts = dwc2_readl(hsotg, GINTSTS);
+ dwc2_writel(hsotg, gintsts | GINTSTS_CONIDSTSCHNG, GINTSTS);
+ }
+}
+
+void dwc2_drd_resume(struct dwc2_hsotg *hsotg)
+{
+ u32 gintsts, gintmsk;
+ enum usb_role role;
+
+ if (hsotg->role_sw) {
+ /* get last known role (as the get ops isn't implemented by this driver) */
+ role = usb_role_switch_get_role(hsotg->role_sw);
+
+ if (role == USB_ROLE_NONE) {
+ if (hsotg->role_sw_default_mode == USB_DR_MODE_HOST)
+ role = USB_ROLE_HOST;
+ else if (hsotg->role_sw_default_mode == USB_DR_MODE_PERIPHERAL)
+ role = USB_ROLE_DEVICE;
+ }
+
+ /* restore last role that may have been lost */
+ if (role == USB_ROLE_HOST)
+ dwc2_ovr_avalid(hsotg, true);
+ else if (role == USB_ROLE_DEVICE)
+ dwc2_ovr_bvalid(hsotg, true);
+
+ dwc2_force_mode(hsotg, role == USB_ROLE_HOST);
+
+ dev_dbg(hsotg->dev, "resuming %s-session valid\n",
+ role == USB_ROLE_NONE ? "No" :
+ role == USB_ROLE_HOST ? "A" : "B");
+ }
+
+ if (hsotg->role_sw && !hsotg->params.external_id_pin_ctl) {
+ gintsts = dwc2_readl(hsotg, GINTSTS);
+ dwc2_writel(hsotg, gintsts | GINTSTS_CONIDSTSCHNG, GINTSTS);
+ gintmsk = dwc2_readl(hsotg, GINTMSK);
+ gintmsk |= GINTSTS_CONIDSTSCHNG;
+ dwc2_writel(hsotg, gintmsk, GINTMSK);
+ }
+}
+
+void dwc2_drd_exit(struct dwc2_hsotg *hsotg)
+{
+ if (hsotg->role_sw)
+ usb_role_switch_unregister(hsotg->role_sw);
+}