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authorLinus Torvalds <torvalds@linux-foundation.org>2019-09-18 10:33:46 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-09-18 10:33:46 -0700
commitc6b48dad92aedaa9bdc013ee495cb5b1bbdf1f11 (patch)
tree8d0bbf19d75fc1bf546ed1b05b560ea2df54689e /drivers/usb/common/usb-conn-gpio.c
parent1f7d290a7275edb270dbee13212c37cb59940221 (diff)
parentfb9617edf6c0e1b86a6595cd92dd3f84595221d9 (diff)
Merge tag 'usb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB updates from Greg KH: "Here is the big set of USB patches for 5.4-rc1. Two major chunks of code are moving out of the tree and into the staging directory, uwb and wusb (wireless USB support), because there are no devices that actually use this protocol anymore, and what we have today probably doesn't work at all given that the maintainers left many many years ago. So move it to staging where it will be removed in a few releases if no one screams. Other than that, lots of little things. The usual gadget and xhci and usb serial driver updates, along with a bunch of sysfs file cleanups due to the driver core changes to support that. Nothing really major, just constant forward progress. All of these have been in linux-next for a while with no reported issues" * tag 'usb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (159 commits) USB: usbcore: Fix slab-out-of-bounds bug during device reset usb: cdns3: Remove redundant dev_err call in cdns3_probe() USB: rio500: Fix lockdep violation USB: rio500: simplify locking usb: mtu3: register a USB Role Switch for dual role mode usb: common: add USB GPIO based connection detection driver usb: common: create Kconfig file usb: roles: get usb-role-switch from parent usb: roles: Add fwnode_usb_role_switch_get() function device connection: Add fwnode_connection_find_match() usb: roles: Introduce stubs for the exiting functions in role.h dt-bindings: usb: mtu3: add properties about USB Role Switch dt-bindings: usb: add binding for USB GPIO based connection detection driver dt-bindings: connector: add optional properties for Type-B dt-binding: usb: add usb-role-switch property usbip: Implement SG support to vhci-hcd and stub driver usb: roles: intel: Enable static DRD mode for role switch xhci-ext-caps.c: Add property to disable Intel SW switch usb: dwc3: remove generic PHY calibrate() calls usb: core: phy: add support for PHY calibration ...
Diffstat (limited to 'drivers/usb/common/usb-conn-gpio.c')
-rw-r--r--drivers/usb/common/usb-conn-gpio.c284
1 files changed, 284 insertions, 0 deletions
diff --git a/drivers/usb/common/usb-conn-gpio.c b/drivers/usb/common/usb-conn-gpio.c
new file mode 100644
index 000000000000..87338f9eb5be
--- /dev/null
+++ b/drivers/usb/common/usb-conn-gpio.c
@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * USB GPIO Based Connection Detection Driver
+ *
+ * Copyright (C) 2019 MediaTek Inc.
+ *
+ * Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
+ *
+ * Some code borrowed from drivers/extcon/extcon-usb-gpio.c
+ */
+
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/usb/role.h>
+
+#define USB_GPIO_DEB_MS 20 /* ms */
+#define USB_GPIO_DEB_US ((USB_GPIO_DEB_MS) * 1000) /* us */
+
+#define USB_CONN_IRQF \
+ (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT)
+
+struct usb_conn_info {
+ struct device *dev;
+ struct usb_role_switch *role_sw;
+ enum usb_role last_role;
+ struct regulator *vbus;
+ struct delayed_work dw_det;
+ unsigned long debounce_jiffies;
+
+ struct gpio_desc *id_gpiod;
+ struct gpio_desc *vbus_gpiod;
+ int id_irq;
+ int vbus_irq;
+};
+
+/**
+ * "DEVICE" = VBUS and "HOST" = !ID, so we have:
+ * Both "DEVICE" and "HOST" can't be set as active at the same time
+ * so if "HOST" is active (i.e. ID is 0) we keep "DEVICE" inactive
+ * even if VBUS is on.
+ *
+ * Role | ID | VBUS
+ * ------------------------------------
+ * [1] DEVICE | H | H
+ * [2] NONE | H | L
+ * [3] HOST | L | H
+ * [4] HOST | L | L
+ *
+ * In case we have only one of these signals:
+ * - VBUS only - we want to distinguish between [1] and [2], so ID is always 1
+ * - ID only - we want to distinguish between [1] and [4], so VBUS = ID
+ */
+static void usb_conn_detect_cable(struct work_struct *work)
+{
+ struct usb_conn_info *info;
+ enum usb_role role;
+ int id, vbus, ret;
+
+ info = container_of(to_delayed_work(work),
+ struct usb_conn_info, dw_det);
+
+ /* check ID and VBUS */
+ id = info->id_gpiod ?
+ gpiod_get_value_cansleep(info->id_gpiod) : 1;
+ vbus = info->vbus_gpiod ?
+ gpiod_get_value_cansleep(info->vbus_gpiod) : id;
+
+ if (!id)
+ role = USB_ROLE_HOST;
+ else if (vbus)
+ role = USB_ROLE_DEVICE;
+ else
+ role = USB_ROLE_NONE;
+
+ dev_dbg(info->dev, "role %d/%d, gpios: id %d, vbus %d\n",
+ info->last_role, role, id, vbus);
+
+ if (info->last_role == role) {
+ dev_warn(info->dev, "repeated role: %d\n", role);
+ return;
+ }
+
+ if (info->last_role == USB_ROLE_HOST)
+ regulator_disable(info->vbus);
+
+ ret = usb_role_switch_set_role(info->role_sw, role);
+ if (ret)
+ dev_err(info->dev, "failed to set role: %d\n", ret);
+
+ if (role == USB_ROLE_HOST) {
+ ret = regulator_enable(info->vbus);
+ if (ret)
+ dev_err(info->dev, "enable vbus regulator failed\n");
+ }
+
+ info->last_role = role;
+
+ dev_dbg(info->dev, "vbus regulator is %s\n",
+ regulator_is_enabled(info->vbus) ? "enabled" : "disabled");
+}
+
+static void usb_conn_queue_dwork(struct usb_conn_info *info,
+ unsigned long delay)
+{
+ queue_delayed_work(system_power_efficient_wq, &info->dw_det, delay);
+}
+
+static irqreturn_t usb_conn_isr(int irq, void *dev_id)
+{
+ struct usb_conn_info *info = dev_id;
+
+ usb_conn_queue_dwork(info, info->debounce_jiffies);
+
+ return IRQ_HANDLED;
+}
+
+static int usb_conn_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct usb_conn_info *info;
+ int ret = 0;
+
+ info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ info->dev = dev;
+ info->id_gpiod = devm_gpiod_get_optional(dev, "id", GPIOD_IN);
+ if (IS_ERR(info->id_gpiod))
+ return PTR_ERR(info->id_gpiod);
+
+ info->vbus_gpiod = devm_gpiod_get_optional(dev, "vbus", GPIOD_IN);
+ if (IS_ERR(info->vbus_gpiod))
+ return PTR_ERR(info->vbus_gpiod);
+
+ if (!info->id_gpiod && !info->vbus_gpiod) {
+ dev_err(dev, "failed to get gpios\n");
+ return -ENODEV;
+ }
+
+ if (info->id_gpiod)
+ ret = gpiod_set_debounce(info->id_gpiod, USB_GPIO_DEB_US);
+ if (!ret && info->vbus_gpiod)
+ ret = gpiod_set_debounce(info->vbus_gpiod, USB_GPIO_DEB_US);
+ if (ret < 0)
+ info->debounce_jiffies = msecs_to_jiffies(USB_GPIO_DEB_MS);
+
+ INIT_DELAYED_WORK(&info->dw_det, usb_conn_detect_cable);
+
+ info->vbus = devm_regulator_get(dev, "vbus");
+ if (IS_ERR(info->vbus)) {
+ dev_err(dev, "failed to get vbus\n");
+ return PTR_ERR(info->vbus);
+ }
+
+ info->role_sw = usb_role_switch_get(dev);
+ if (IS_ERR(info->role_sw)) {
+ if (PTR_ERR(info->role_sw) != -EPROBE_DEFER)
+ dev_err(dev, "failed to get role switch\n");
+
+ return PTR_ERR(info->role_sw);
+ }
+
+ if (info->id_gpiod) {
+ info->id_irq = gpiod_to_irq(info->id_gpiod);
+ if (info->id_irq < 0) {
+ dev_err(dev, "failed to get ID IRQ\n");
+ ret = info->id_irq;
+ goto put_role_sw;
+ }
+
+ ret = devm_request_threaded_irq(dev, info->id_irq, NULL,
+ usb_conn_isr, USB_CONN_IRQF,
+ pdev->name, info);
+ if (ret < 0) {
+ dev_err(dev, "failed to request ID IRQ\n");
+ goto put_role_sw;
+ }
+ }
+
+ if (info->vbus_gpiod) {
+ info->vbus_irq = gpiod_to_irq(info->vbus_gpiod);
+ if (info->vbus_irq < 0) {
+ dev_err(dev, "failed to get VBUS IRQ\n");
+ ret = info->vbus_irq;
+ goto put_role_sw;
+ }
+
+ ret = devm_request_threaded_irq(dev, info->vbus_irq, NULL,
+ usb_conn_isr, USB_CONN_IRQF,
+ pdev->name, info);
+ if (ret < 0) {
+ dev_err(dev, "failed to request VBUS IRQ\n");
+ goto put_role_sw;
+ }
+ }
+
+ platform_set_drvdata(pdev, info);
+
+ /* Perform initial detection */
+ usb_conn_queue_dwork(info, 0);
+
+ return 0;
+
+put_role_sw:
+ usb_role_switch_put(info->role_sw);
+ return ret;
+}
+
+static int usb_conn_remove(struct platform_device *pdev)
+{
+ struct usb_conn_info *info = platform_get_drvdata(pdev);
+
+ cancel_delayed_work_sync(&info->dw_det);
+
+ if (info->last_role == USB_ROLE_HOST)
+ regulator_disable(info->vbus);
+
+ usb_role_switch_put(info->role_sw);
+
+ return 0;
+}
+
+static int __maybe_unused usb_conn_suspend(struct device *dev)
+{
+ struct usb_conn_info *info = dev_get_drvdata(dev);
+
+ if (info->id_gpiod)
+ disable_irq(info->id_irq);
+ if (info->vbus_gpiod)
+ disable_irq(info->vbus_irq);
+
+ pinctrl_pm_select_sleep_state(dev);
+
+ return 0;
+}
+
+static int __maybe_unused usb_conn_resume(struct device *dev)
+{
+ struct usb_conn_info *info = dev_get_drvdata(dev);
+
+ pinctrl_pm_select_default_state(dev);
+
+ if (info->id_gpiod)
+ enable_irq(info->id_irq);
+ if (info->vbus_gpiod)
+ enable_irq(info->vbus_irq);
+
+ usb_conn_queue_dwork(info, 0);
+
+ return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(usb_conn_pm_ops,
+ usb_conn_suspend, usb_conn_resume);
+
+static const struct of_device_id usb_conn_dt_match[] = {
+ { .compatible = "gpio-usb-b-connector", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, usb_conn_dt_match);
+
+static struct platform_driver usb_conn_driver = {
+ .probe = usb_conn_probe,
+ .remove = usb_conn_remove,
+ .driver = {
+ .name = "usb-conn-gpio",
+ .pm = &usb_conn_pm_ops,
+ .of_match_table = usb_conn_dt_match,
+ },
+};
+
+module_platform_driver(usb_conn_driver);
+
+MODULE_AUTHOR("Chunfeng Yun <chunfeng.yun@mediatek.com>");
+MODULE_DESCRIPTION("USB GPIO based connection detection driver");
+MODULE_LICENSE("GPL v2");