[v3] phy: rcar-gen2 usb: Add Host/Function switching for USB0

Message ID	1436270121-25924-1-git-send-email-phil.edworthy@renesas.com (mailing list archive)
State	Superseded
Delegated to:	Geert Uytterhoeven
Headers	show Return-Path: <linux-sh-owner@kernel.org> From: Phil Edworthy <phil.edworthy@renesas.com> To: Kishon Vijay Abraham I <kishon@ti.com> Cc: Rob Herring <robh+dt@kernel.org>, Pawel Moll <pawel.moll@arm.com>, Mark Rutland <mark.rutland@arm.com>, Ian Campbell <ijc+devicetree@hellion.org.uk>, Kumar Gala <galak@codeaurora.org>, Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>, Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>, <devicetree@vger.kernel.org>, <linux-kernel@vger.kernel.org>, <linux-usb@vger.kernel.org>, <linux-sh@vger.kernel.org>, Phil Edworthy <phil.edworthy@renesas.com> In-Reply-To: <SG2PR06MB0919835888EBD162D4B86C24D8930@SG2PR06MB0919.apcprd06.prod.outlook.com> References: <SG2PR06MB0919835888EBD162D4B86C24D8930@SG2PR06MB0919.apcprd06.prod.outlook.com> Message-ID: <1436270121-25924-1-git-send-email-phil.edworthy@renesas.com> Date: Tue, 7 Jul 2015 12:55:21 +0100 Subject: [PATCH v3] phy: rcar-gen2 usb: Add Host/Function switching for USB0 Sender: linux-sh-owner@vger.kernel.org Precedence: bulk

diff --git a/Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt b/Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt index 00fc52a..3a501fe 100644 --- a/Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt +++ b/Documentation/devicetree/bindings/phy/rcar-gen2-phy.txt @@ -30,6 +30,16 @@ the USB channel; see the selector meanings below: | 2 | PCI EHCI/OHCI | xHCI | +-----------+---------------+---------------+ +Optional properties: + - renesas,pwr-gpio: A gpio specifier that will be active when the + PHY is powered on. + - renesas,id-gpio: A gpio specifier that is read to get the USB + ID signal. + - renesas,vbus-gpio: A gpio specifier that is read to get the USB + VBUS signal. + - renesas,vbus-pwr-gpio: A gpio specifier that will be active when VBUS + is required to be powered. + Example (Lager board): usb-phy@e6590100 { diff --git a/drivers/phy/phy-rcar-gen2.c b/drivers/phy/phy-rcar-gen2.c index 97d45f4..1286892 100644 --- a/drivers/phy/phy-rcar-gen2.c +++ b/drivers/phy/phy-rcar-gen2.c @@ -1,5 +1,5 @@ /* - * Renesas R-Car Gen2 PHY driver + * Renesas R-Car Gen2 USB PHY driver * * Copyright (C) 2014 Renesas Solutions Corp. * Copyright (C) 2014 Cogent Embedded, Inc. @@ -12,11 +12,16 @@ #include <linux/clk.h> #include <linux/delay.h> #include <linux/io.h> +#include <linux/interrupt.h> #include <linux/module.h> #include <linux/of.h> +#include <linux/of_gpio.h> #include <linux/phy/phy.h> #include <linux/platform_device.h> #include <linux/spinlock.h> +#include <linux/usb/gadget.h> +#include <linux/usb/otg.h> +#include <linux/workqueue.h> #include <asm/cmpxchg.h> @@ -58,6 +63,18 @@ struct rcar_gen2_channel { struct rcar_gen2_phy phys[PHYS_PER_CHANNEL]; int selected_phy; u32 select_mask; + + /* external power enable pin */ + int gpio_pwr; + + /* Host/Function switching */ + struct delayed_work work; + int use_otg; + int gpio_vbus; + int gpio_id; + int gpio_vbus_pwr; + struct usb_phy *usbphy; + struct usb_otg *otg; }; struct rcar_gen2_phy_driver { @@ -68,31 +85,50 @@ struct rcar_gen2_phy_driver { struct rcar_gen2_channel *channels; }; -static int rcar_gen2_phy_init(struct phy *p) +static void rcar_gen2_phy_switch(struct rcar_gen2_channel *channel, + u32 select_value) { - struct rcar_gen2_phy *phy = phy_get_drvdata(p); - struct rcar_gen2_channel *channel = phy->channel; struct rcar_gen2_phy_driver *drv = channel->drv; unsigned long flags; u32 ugctrl2; - /* - * Try to acquire exclusive access to PHY. The first driver calling - * phy_init() on a given channel wins, and all attempts to use another - * PHY on this channel will fail until phy_exit() is called by the first - * driver. Achieving this with cmpxcgh() should be SMP-safe. - */ - if (cmpxchg(&channel->selected_phy, -1, phy->number) != -1) - return -EBUSY; - - clk_prepare_enable(drv->clk); - spin_lock_irqsave(&drv->lock, flags); ugctrl2 = readl(drv->base + USBHS_UGCTRL2); ugctrl2 &= ~channel->select_mask; - ugctrl2 |= phy->select_value; + ugctrl2 |= select_value; writel(ugctrl2, drv->base + USBHS_UGCTRL2); spin_unlock_irqrestore(&drv->lock, flags); +} + +static int rcar_gen2_phy_init(struct phy *p) +{ + struct rcar_gen2_phy *phy = phy_get_drvdata(p); + struct rcar_gen2_channel *channel = phy->channel; + struct rcar_gen2_phy_driver *drv = channel->drv; + + if (!channel->use_otg) { + /* + * Static Host/Function role. + * Try to acquire exclusive access to PHY. The first driver + * calling phy_init() on a given channel wins, and all attempts + * to use another PHY on this channel will fail until + * phy_exit() is called by the first driver. Achieving this + * with cmpxcgh() should be SMP-safe. + */ + if (cmpxchg(&channel->selected_phy, -1, phy->number) != -1) + return -EBUSY; + + clk_prepare_enable(drv->clk); + rcar_gen2_phy_switch(channel, phy->select_value); + } else { + /* + * Using Host/Function switching, so schedule work to determine + * which role to use. + */ + clk_prepare_enable(drv->clk); + schedule_delayed_work(&channel->work, 100); + } + return 0; } @@ -117,9 +153,9 @@ static int rcar_gen2_phy_power_on(struct phy *p) u32 value; int err = 0, i; - /* Skip if it's not USBHS */ - if (phy->select_value != USBHS_UGCTRL2_USB0SEL_HS_USB) - return 0; + /* Optional external power pin */ + if (gpio_is_valid(phy->channel->gpio_pwr)) + gpio_direction_output(phy->channel->gpio_pwr, 1); spin_lock_irqsave(&drv->lock, flags); @@ -160,9 +196,9 @@ static int rcar_gen2_phy_power_off(struct phy *p) unsigned long flags; u32 value; - /* Skip if it's not USBHS */ - if (phy->select_value != USBHS_UGCTRL2_USB0SEL_HS_USB) - return 0; + /* External power pin */ + if (gpio_is_valid(phy->channel->gpio_pwr)) + gpio_direction_output(phy->channel->gpio_pwr, 0); spin_lock_irqsave(&drv->lock, flags); @@ -236,6 +272,132 @@ static const u32 select_value[][PHYS_PER_CHANNEL] = { [2] = { USBHS_UGCTRL2_USB2SEL_PCI, USBHS_UGCTRL2_USB2SEL_USB30 }, }; + +#define VBUS_IRQ_FLAGS \ + (IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING) + +static void gpio_vbus_work(struct work_struct *work) +{ + struct rcar_gen2_channel *channel = container_of(work, + struct rcar_gen2_channel, work.work); + struct usb_phy *usbphy = channel->usbphy; + int status, vbus, id; + + vbus = !!gpio_get_value(channel->gpio_vbus); + id = !!gpio_get_value(channel->gpio_id); + + /* Switch the PHY over */ + if (id) + rcar_gen2_phy_switch(channel, USBHS_UGCTRL2_USB0SEL_HS_USB); + else + rcar_gen2_phy_switch(channel, USBHS_UGCTRL2_USB0SEL_PCI); + + /* If VBUS is powered and we are not the initial Host, turn off VBUS */ + if (gpio_is_valid(channel->gpio_vbus_pwr)) + gpio_direction_output(channel->gpio_vbus_pwr, !(id && vbus)); + + if (!channel->otg->gadget) + return; + + /* Function handling: vbus=1 when initially plugged into a Host */ + if (vbus) { + status = USB_EVENT_VBUS; + usbphy->otg->state = OTG_STATE_B_PERIPHERAL; + usbphy->last_event = status; + usb_gadget_vbus_connect(usbphy->otg->gadget); + + atomic_notifier_call_chain(&usbphy->notifier, + status, usbphy->otg->gadget); + } else { + usb_gadget_vbus_disconnect(usbphy->otg->gadget); + status = USB_EVENT_NONE; + usbphy->otg->state = OTG_STATE_B_IDLE; + usbphy->last_event = status; + + atomic_notifier_call_chain(&usbphy->notifier, + status, usbphy->otg->gadget); + } +} + +/* VBUS change IRQ handler */ +static irqreturn_t gpio_vbus_irq(int irq, void *data) +{ + struct rcar_gen2_channel *channel = data; + + /* Wait 20ms before doing anything as VBUS needs to settle */ + schedule_delayed_work(&channel->work, msecs_to_jiffies(20)); + + return IRQ_HANDLED; +} + +static int probe_otg(struct platform_device *pdev, + struct rcar_gen2_phy_driver *drv) +{ + struct device *dev = &pdev->dev; + struct rcar_gen2_channel *ch = drv->channels; + int irq; + int ret; + + /* GPIOs for Host/Fn switching */ + ch->gpio_id = of_get_named_gpio_flags(dev->of_node, + "renesas,id-gpio", 0, NULL); + ch->gpio_vbus = of_get_named_gpio_flags(dev->of_node, + "renesas,vbus-gpio", 0, NULL); + + /* Need valid ID and VBUS gpios for Host/Fn switching */ + if (gpio_is_valid(ch->gpio_id) && gpio_is_valid(ch->gpio_vbus)) { + ch->use_otg = 1; + + /* GPIO for ID input */ + ret = devm_gpio_request_one(dev, ch->gpio_id, GPIOF_IN, "id"); + if (ret) + return ret; + + /* GPIO for VBUS input */ + ret = devm_gpio_request_one(dev, ch->gpio_vbus, GPIOF_IN, "vbus"); + if (ret) + return ret; + + irq = gpio_to_irq(ch->gpio_vbus); + ret = devm_request_irq(dev, irq, gpio_vbus_irq, VBUS_IRQ_FLAGS, + "vbus_detect", ch); + if (ret) + return ret; + + /* Optional GPIO for VBUS power */ + ch->gpio_vbus_pwr = of_get_named_gpio_flags(dev->of_node, + "renesas,vbus-pwr-gpio", 0, NULL); + if (gpio_is_valid(ch->gpio_id)) { + ret = devm_gpio_request_one(dev, ch->gpio_vbus_pwr, + GPIOF_OUT_INIT_LOW, "vbus-pwr"); + if (ret) + return ret; + } + + } else if (gpio_is_valid(ch->gpio_id)) { + dev_err(dev, "Failed to get VBUS gpio\n"); + return ch->gpio_vbus; + } else if (gpio_is_valid(ch->gpio_vbus)) { + dev_err(dev, "Failed to get ID gpio\n"); + return ch->gpio_id; + } + + return 0; +} + +/* bind/unbind the peripheral controller */ +static int rcar_gen2_usb_set_peripheral(struct usb_otg *otg, + struct usb_gadget *gadget) +{ + if (!gadget) { + usb_gadget_vbus_disconnect(otg->gadget); + otg->state = OTG_STATE_UNDEFINED; + } + otg->gadget = gadget; + + return 0; +} + static int rcar_gen2_phy_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -245,7 +407,9 @@ static int rcar_gen2_phy_probe(struct platform_device *pdev) struct resource *res; void __iomem *base; struct clk *clk; + struct usb_otg *otg; int i = 0; + int err; if (!dev->of_node) { dev_err(dev, @@ -280,6 +444,57 @@ static int rcar_gen2_phy_probe(struct platform_device *pdev) if (!drv->channels) return -ENOMEM; + /* USB0 optional GPIO power pin for external devices */ + drv->channels->gpio_pwr = of_get_named_gpio_flags(dev->of_node, + "renesas,pwr-gpio", 0, NULL); + if (drv->channels->gpio_pwr == -EPROBE_DEFER) + return -EPROBE_DEFER; + + if (gpio_is_valid(drv->channels->gpio_pwr)) { + err = devm_gpio_request(dev, drv->channels->gpio_pwr, "pwr"); + if (err) + return err; + } + + /* USB0 Host/Function switching info */ + err = probe_otg(pdev, drv); + if (err) + return err; + + /* + * The PHY connected to channel 0 can be used to steer signals to the + * USB Host IP that stils behind a PCI bridge (pci0), or the USB Func + * IP (hsusb). We can dynamically switch this based on VBUS and ID + * signals connected to gpios, to get something approaching OTG. + */ + if (drv->channels->use_otg) { + struct usb_phy *usbphy; + + usbphy = devm_kzalloc(dev, sizeof(*usbphy), GFP_KERNEL); + if (!usbphy) + return -ENOMEM; + + otg = devm_kzalloc(dev, sizeof(*otg), GFP_KERNEL); + if (!otg) + return -ENOMEM; + + usbphy->dev = dev; + usbphy->otg = otg; + + otg->usb_phy = usbphy; + otg->state = OTG_STATE_UNDEFINED; + otg->set_peripheral = rcar_gen2_usb_set_peripheral; + + drv->channels->otg = otg; + drv->channels->usbphy = usbphy; + + ATOMIC_INIT_NOTIFIER_HEAD(&usbphy->notifier); + + INIT_DELAYED_WORK(&drv->channels->work, gpio_vbus_work); + + usb_add_phy_dev(usbphy); + } + for_each_child_of_node(dev->of_node, np) { struct rcar_gen2_channel *channel = drv->channels + i; u32 channel_num; @@ -288,6 +503,8 @@ static int rcar_gen2_phy_probe(struct platform_device *pdev) channel->of_node = np; channel->drv = drv; channel->selected_phy = -1; + if (i != 0) + channel->gpio_pwr = -ENOENT; error = of_property_read_u32(np, "reg", &channel_num); if (error || channel_num > 2) { @@ -323,6 +540,14 @@ static int rcar_gen2_phy_probe(struct platform_device *pdev) dev_set_drvdata(dev, drv); + /* + * If we already have something plugged into USB0, we won't get an edge + * on VBUS, so we have to manually schedule work to look at the VBUS + * and ID signals. + */ + if (drv->channels->use_otg) + schedule_delayed_work(&drv->channels->work, msecs_to_jiffies(100)); + return 0; }

[v3] phy: rcar-gen2 usb: Add Host/Function switching for USB0

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