From: Roger Quadros <rogerq@ti.com> To: <peter.chen@freescale.com>, <robh@kernel.org> Cc: <balbi@kernel.org>, <tony@atomide.com>, <gregkh@linuxfoundation.org>, <dan.j.williams@intel.com>, <mathias.nyman@linux.intel.com>, <Joao.Pinto@synopsys.com>, <sergei.shtylyov@cogentembedded.com>, <jun.li@freescale.com>, <grygorii.strashko@ti.com>, <yoshihiro.shimoda.uh@renesas.com>, <nsekhar@ti.com>, <b-liu@ti.com>, <linux-usb@vger.kernel.org>, <linux-omap@vger.kernel.org>, <linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>, <rogerq@ti.com> Subject: [PATCH v9 10/14] usb: otg: add hcd companion support Date: Fri, 20 May 2016 12:32:27 +0300 [thread overview] Message-ID: <573ED9AB.6010508@ti.com> (raw) In-Reply-To: <1463133808-10630-11-git-send-email-rogerq@ti.com> Since some host controller (e.g. EHCI) needs a companion host controller (e.g. OHCI), this patch adds such a configuration to use it in the OTG core. Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Peter Chen <peter.chen@nxp.com> --- v9: - add DT property documentation under OTG controllers. Documentation/devicetree/bindings/usb/generic.txt | 3 +++ drivers/usb/common/usb-otg.c | 32 ++++++++++++++++------- include/linux/usb/otg.h | 7 ++++- 3 files changed, 32 insertions(+), 10 deletions(-) diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt index 0887d6e..6013296 100644 --- a/Documentation/devicetree/bindings/usb/generic.txt +++ b/Documentation/devicetree/bindings/usb/generic.txt @@ -26,6 +26,9 @@ Optional properties for OTG controllers: optional for OTG device. - adp-disable: tells OTG controllers we want to disable OTG ADP, ADP is optional for OTG device. + - hcd-needs-companion: must be present if otg controller is dealing with + EHCI host controller that needs a companion OHCI host + controller. Optional properties for host/device controllers: - otg-controller: phandle to otg controller. Host or gadget controllers can diff --git a/drivers/usb/common/usb-otg.c b/drivers/usb/common/usb-otg.c index 64be6df..8a2a0d4 100644 --- a/drivers/usb/common/usb-otg.c +++ b/drivers/usb/common/usb-otg.c @@ -18,6 +18,7 @@ #include <linux/list.h> #include <linux/of.h> #include <linux/of_platform.h> +#include <linux/usb/of.h> #include <linux/usb/otg.h> #include <linux/usb/gadget.h> #include <linux/workqueue.h> @@ -584,6 +585,10 @@ struct usb_otg *usb_otg_register(struct device *dev, else INIT_WORK(&otg->work, usb_drd_work); + if (of_find_property(dev->of_node, "hcd-needs-companion", NULL) || + config->hcd_needs_companion) /* needs companion ? */ + otg->flags |= OTG_FLAG_HCD_NEEDS_COMPANION; + otg->wq = create_freezable_workqueue("usb_otg"); if (!otg->wq) { dev_err(dev, "otg: %s: can't create workqueue\n", @@ -807,15 +812,18 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum, /* HCD will be started by OTG fsm when needed */ mutex_lock(&otg->fsm.lock); if (otg->primary_hcd.hcd) { - /* probably a shared HCD ? */ - if (usb_otg_hcd_is_primary_hcd(hcd)) { + /* probably a shared HCD or a companion OHCI HCD ? */ + if (!(otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION) && + usb_otg_hcd_is_primary_hcd(hcd)) { dev_err(otg_dev, "otg: primary host already registered\n"); goto err; } - if (hcd->shared_hcd == otg->primary_hcd.hcd) { + if (otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION || + (hcd->shared_hcd == otg->primary_hcd.hcd)) { if (otg->shared_hcd.hcd) { - dev_err(otg_dev, "otg: shared host already registered\n"); + dev_err(otg_dev, + "otg: shared/companion host already registered\n"); goto err; } @@ -823,10 +831,12 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum, otg->shared_hcd.irqnum = irqnum; otg->shared_hcd.irqflags = irqflags; otg->shared_hcd.ops = ops; - dev_info(otg_dev, "otg: shared host %s registered\n", + dev_info(otg_dev, + "otg: shared/companion host %s registered\n", dev_name(hcd->self.controller)); } else { - dev_err(otg_dev, "otg: invalid shared host %s\n", + dev_err(otg_dev, + "otg: invalid shared/companion host %s\n", dev_name(hcd->self.controller)); goto err; } @@ -849,14 +859,17 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum, * we're ready only if we have shared HCD * or we don't need shared HCD. */ - if (otg->shared_hcd.hcd || !otg->primary_hcd.hcd->shared_hcd) { + if (otg->shared_hcd.hcd || + (!(otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION) && + !otg->primary_hcd.hcd->shared_hcd)) { otg->host = hcd_to_bus(hcd); /* FIXME: set bus->otg_port if this is true OTG port with HNP */ /* start FSM */ usb_otg_start_fsm(otg); } else { - dev_dbg(otg_dev, "otg: can't start till shared host registers\n"); + dev_dbg(otg_dev, + "otg: can't start till shared/companion host registers\n"); } mutex_unlock(&otg->fsm.lock); @@ -907,7 +920,8 @@ int usb_otg_unregister_hcd(struct usb_hcd *hcd) dev_name(hcd_dev)); } else if (hcd == otg->shared_hcd.hcd) { otg->shared_hcd.hcd = NULL; - dev_info(otg_dev, "otg: shared host %s unregistered\n", + dev_info(otg_dev, + "otg: shared/companion host %s unregistered\n", dev_name(hcd_dev)); } else { dev_err(otg_dev, "otg: host %s wasn't registered with otg\n", diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h index b094352..6f4ca77 100644 --- a/include/linux/usb/otg.h +++ b/include/linux/usb/otg.h @@ -57,7 +57,8 @@ struct otg_hcd { * @list: list of otg controllers * @work: otg state machine work * @wq: otg state machine work queue - * @flags: to track if host/gadget is running + * @flags: to track if host/gadget is running, or to indicate if hcd needs + * companion */ struct usb_otg { u8 default_a; @@ -84,6 +85,7 @@ struct usb_otg { u32 flags; #define OTG_FLAG_GADGET_RUNNING (1 << 0) #define OTG_FLAG_HOST_RUNNING (1 << 1) +#define OTG_FLAG_HCD_NEEDS_COMPANION (1 << 2) /* use otg->fsm.lock for serializing access */ /*------------- deprecated interface -----------------------------*/ @@ -125,11 +127,14 @@ struct usb_otg_caps { * @caps: otg capabilities of the controller * @ops: otg fsm operations * @otg_work: optional custom otg state machine work function + * @hcd_needs_companion: Indicates if host controller needs a companion + * controller */ struct usb_otg_config { struct usb_otg_caps *otg_caps; struct otg_fsm_ops *fsm_ops; void (*otg_work)(struct work_struct *work); + bool hcd_needs_companion; }; extern const char *usb_otg_state_string(enum usb_otg_state state); -- 2.7.4
WARNING: multiple messages have this Message-ID (diff)
From: Roger Quadros <rogerq@ti.com> To: peter.chen@freescale.com, robh@kernel.org Cc: balbi@kernel.org, tony@atomide.com, gregkh@linuxfoundation.org, dan.j.williams@intel.com, mathias.nyman@linux.intel.com, Joao.Pinto@synopsys.com, sergei.shtylyov@cogentembedded.com, jun.li@freescale.com, grygorii.strashko@ti.com, yoshihiro.shimoda.uh@renesas.com, nsekhar@ti.com, b-liu@ti.com, linux-usb@vger.kernel.org, linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, rogerq@ti.com Subject: [PATCH v9 10/14] usb: otg: add hcd companion support Date: Fri, 20 May 2016 12:32:27 +0300 [thread overview] Message-ID: <573ED9AB.6010508@ti.com> (raw) In-Reply-To: <1463133808-10630-11-git-send-email-rogerq@ti.com> Since some host controller (e.g. EHCI) needs a companion host controller (e.g. OHCI), this patch adds such a configuration to use it in the OTG core. Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Peter Chen <peter.chen@nxp.com> --- v9: - add DT property documentation under OTG controllers. Documentation/devicetree/bindings/usb/generic.txt | 3 +++ drivers/usb/common/usb-otg.c | 32 ++++++++++++++++------- include/linux/usb/otg.h | 7 ++++- 3 files changed, 32 insertions(+), 10 deletions(-) diff --git a/Documentation/devicetree/bindings/usb/generic.txt b/Documentation/devicetree/bindings/usb/generic.txt index 0887d6e..6013296 100644 --- a/Documentation/devicetree/bindings/usb/generic.txt +++ b/Documentation/devicetree/bindings/usb/generic.txt @@ -26,6 +26,9 @@ Optional properties for OTG controllers: optional for OTG device. - adp-disable: tells OTG controllers we want to disable OTG ADP, ADP is optional for OTG device. + - hcd-needs-companion: must be present if otg controller is dealing with + EHCI host controller that needs a companion OHCI host + controller. Optional properties for host/device controllers: - otg-controller: phandle to otg controller. Host or gadget controllers can diff --git a/drivers/usb/common/usb-otg.c b/drivers/usb/common/usb-otg.c index 64be6df..8a2a0d4 100644 --- a/drivers/usb/common/usb-otg.c +++ b/drivers/usb/common/usb-otg.c @@ -18,6 +18,7 @@ #include <linux/list.h> #include <linux/of.h> #include <linux/of_platform.h> +#include <linux/usb/of.h> #include <linux/usb/otg.h> #include <linux/usb/gadget.h> #include <linux/workqueue.h> @@ -584,6 +585,10 @@ struct usb_otg *usb_otg_register(struct device *dev, else INIT_WORK(&otg->work, usb_drd_work); + if (of_find_property(dev->of_node, "hcd-needs-companion", NULL) || + config->hcd_needs_companion) /* needs companion ? */ + otg->flags |= OTG_FLAG_HCD_NEEDS_COMPANION; + otg->wq = create_freezable_workqueue("usb_otg"); if (!otg->wq) { dev_err(dev, "otg: %s: can't create workqueue\n", @@ -807,15 +812,18 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum, /* HCD will be started by OTG fsm when needed */ mutex_lock(&otg->fsm.lock); if (otg->primary_hcd.hcd) { - /* probably a shared HCD ? */ - if (usb_otg_hcd_is_primary_hcd(hcd)) { + /* probably a shared HCD or a companion OHCI HCD ? */ + if (!(otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION) && + usb_otg_hcd_is_primary_hcd(hcd)) { dev_err(otg_dev, "otg: primary host already registered\n"); goto err; } - if (hcd->shared_hcd == otg->primary_hcd.hcd) { + if (otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION || + (hcd->shared_hcd == otg->primary_hcd.hcd)) { if (otg->shared_hcd.hcd) { - dev_err(otg_dev, "otg: shared host already registered\n"); + dev_err(otg_dev, + "otg: shared/companion host already registered\n"); goto err; } @@ -823,10 +831,12 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum, otg->shared_hcd.irqnum = irqnum; otg->shared_hcd.irqflags = irqflags; otg->shared_hcd.ops = ops; - dev_info(otg_dev, "otg: shared host %s registered\n", + dev_info(otg_dev, + "otg: shared/companion host %s registered\n", dev_name(hcd->self.controller)); } else { - dev_err(otg_dev, "otg: invalid shared host %s\n", + dev_err(otg_dev, + "otg: invalid shared/companion host %s\n", dev_name(hcd->self.controller)); goto err; } @@ -849,14 +859,17 @@ int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum, * we're ready only if we have shared HCD * or we don't need shared HCD. */ - if (otg->shared_hcd.hcd || !otg->primary_hcd.hcd->shared_hcd) { + if (otg->shared_hcd.hcd || + (!(otg->flags & OTG_FLAG_HCD_NEEDS_COMPANION) && + !otg->primary_hcd.hcd->shared_hcd)) { otg->host = hcd_to_bus(hcd); /* FIXME: set bus->otg_port if this is true OTG port with HNP */ /* start FSM */ usb_otg_start_fsm(otg); } else { - dev_dbg(otg_dev, "otg: can't start till shared host registers\n"); + dev_dbg(otg_dev, + "otg: can't start till shared/companion host registers\n"); } mutex_unlock(&otg->fsm.lock); @@ -907,7 +920,8 @@ int usb_otg_unregister_hcd(struct usb_hcd *hcd) dev_name(hcd_dev)); } else if (hcd == otg->shared_hcd.hcd) { otg->shared_hcd.hcd = NULL; - dev_info(otg_dev, "otg: shared host %s unregistered\n", + dev_info(otg_dev, + "otg: shared/companion host %s unregistered\n", dev_name(hcd_dev)); } else { dev_err(otg_dev, "otg: host %s wasn't registered with otg\n", diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h index b094352..6f4ca77 100644 --- a/include/linux/usb/otg.h +++ b/include/linux/usb/otg.h @@ -57,7 +57,8 @@ struct otg_hcd { * @list: list of otg controllers * @work: otg state machine work * @wq: otg state machine work queue - * @flags: to track if host/gadget is running + * @flags: to track if host/gadget is running, or to indicate if hcd needs + * companion */ struct usb_otg { u8 default_a; @@ -84,6 +85,7 @@ struct usb_otg { u32 flags; #define OTG_FLAG_GADGET_RUNNING (1 << 0) #define OTG_FLAG_HOST_RUNNING (1 << 1) +#define OTG_FLAG_HCD_NEEDS_COMPANION (1 << 2) /* use otg->fsm.lock for serializing access */ /*------------- deprecated interface -----------------------------*/ @@ -125,11 +127,14 @@ struct usb_otg_caps { * @caps: otg capabilities of the controller * @ops: otg fsm operations * @otg_work: optional custom otg state machine work function + * @hcd_needs_companion: Indicates if host controller needs a companion + * controller */ struct usb_otg_config { struct usb_otg_caps *otg_caps; struct otg_fsm_ops *fsm_ops; void (*otg_work)(struct work_struct *work); + bool hcd_needs_companion; }; extern const char *usb_otg_state_string(enum usb_otg_state state); -- 2.7.4
next prev parent reply other threads:[~2016-05-20 9:32 UTC|newest] Thread overview: 123+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-05-13 10:03 [PATCH v8 00/14] USB OTG/dual-role framework Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 01/14] usb: hcd: Initialize hcd->flags to 0 Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 02/14] usb: otg-fsm: Prevent build warning "VDBG" redefined Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 03/14] usb: hcd.h: Add OTG to HCD interface Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 04/14] usb: otg-fsm: use usb_otg wherever possible Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 05/14] usb: otg-fsm: move host controller operations into usb_otg->hcd_ops Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 06/14] usb: gadget.h: Add OTG to gadget interface Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 07/14] usb: otg: get rid of CONFIG_USB_OTG_FSM in favour of CONFIG_USB_OTG Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 08/14] usb: otg: add OTG/dual-role core Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-16 9:00 ` Roger Quadros 2016-05-16 9:00 ` Roger Quadros 2016-05-18 7:45 ` Peter Chen 2016-05-18 12:59 ` Roger Quadros 2016-05-18 12:59 ` Roger Quadros 2016-05-20 8:31 ` Roger Quadros 2016-05-20 8:31 ` Roger Quadros 2016-05-20 9:19 ` Roger Quadros 2016-05-20 9:19 ` Roger Quadros 2016-05-20 9:53 ` Peter Chen 2016-05-20 9:53 ` Peter Chen 2016-05-23 10:06 ` Roger Quadros 2016-05-23 10:06 ` Roger Quadros 2016-05-24 9:45 ` Roger Quadros 2016-05-24 9:45 ` Roger Quadros 2016-05-25 2:44 ` Peter Chen 2016-05-25 3:19 ` Jun Li 2016-05-25 3:19 ` Jun Li 2016-05-25 12:26 ` Roger Quadros 2016-05-25 12:26 ` Roger Quadros 2016-05-25 12:21 ` Roger Quadros 2016-05-25 12:21 ` Roger Quadros 2016-05-25 14:44 ` Jun Li 2016-05-25 14:44 ` Jun Li 2016-05-27 8:03 ` Peter Chen 2016-05-27 8:12 ` Peter Chen 2016-05-13 10:03 ` [PATCH v8 09/14] usb: of: add an API to get OTG device from USB controller node Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-20 9:29 ` [PATCH v9 " Roger Quadros 2016-05-20 9:29 ` Roger Quadros 2016-05-23 21:06 ` Rob Herring 2016-05-13 10:03 ` [PATCH v8 10/14] usb: otg: add hcd companion support Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 18:13 ` Rob Herring 2016-05-13 18:13 ` Rob Herring 2016-05-16 8:12 ` Roger Quadros 2016-05-16 8:12 ` Roger Quadros 2016-05-20 9:32 ` Roger Quadros [this message] 2016-05-20 9:32 ` [PATCH v9 " Roger Quadros 2016-05-23 21:07 ` Rob Herring 2016-05-13 10:03 ` [PATCH v8 11/14] usb: otg: use dev_dbg() instead of VDBG() Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 12/14] usb: hcd: Adapt to OTG core Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 13/14] usb: gadget: udc: adapt " Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-16 7:02 ` Peter Chen 2016-05-16 8:26 ` Roger Quadros 2016-05-16 8:26 ` Roger Quadros 2016-05-16 9:23 ` Peter Chen 2016-05-16 9:23 ` Peter Chen 2016-05-16 9:51 ` Roger Quadros 2016-05-16 9:51 ` Roger Quadros 2016-05-17 7:38 ` Jun Li 2016-05-17 7:38 ` Jun Li 2016-05-17 8:08 ` Roger Quadros 2016-05-17 8:08 ` Roger Quadros 2016-05-17 8:28 ` Jun Li 2016-05-17 8:28 ` Jun Li 2016-05-18 12:42 ` Roger Quadros 2016-05-18 12:42 ` Roger Quadros 2016-05-18 13:12 ` Jun Li 2016-05-18 13:12 ` Jun Li 2016-05-18 13:43 ` Roger Quadros 2016-05-18 13:43 ` Roger Quadros 2016-05-18 14:46 ` Jun Li 2016-05-18 14:46 ` Jun Li 2016-05-19 7:32 ` Roger Quadros 2016-05-19 7:32 ` Roger Quadros 2016-05-21 2:29 ` Peter Chen 2016-05-21 2:29 ` Peter Chen 2016-05-23 3:21 ` Peter Chen 2016-05-23 3:21 ` Peter Chen 2016-05-23 10:11 ` Roger Quadros 2016-05-23 10:11 ` Roger Quadros 2016-05-23 10:34 ` Jun Li 2016-05-23 10:34 ` Jun Li 2016-05-23 10:36 ` Roger Quadros 2016-05-23 10:36 ` Roger Quadros 2016-05-24 2:53 ` Peter Chen 2016-05-24 2:53 ` Peter Chen 2016-06-08 7:32 ` Roger Quadros 2016-06-08 7:32 ` Roger Quadros 2016-06-08 9:05 ` Peter Chen 2016-06-08 9:05 ` Peter Chen 2016-05-18 3:18 ` Peter Chen 2016-05-18 12:45 ` Roger Quadros 2016-05-18 12:45 ` Roger Quadros 2016-05-20 1:39 ` Peter Chen 2016-05-20 1:39 ` Peter Chen 2016-05-20 7:26 ` Roger Quadros 2016-05-20 7:26 ` Roger Quadros 2016-05-21 2:44 ` Peter Chen 2016-05-21 2:44 ` Peter Chen 2016-06-01 7:38 ` Peter Chen 2016-06-02 11:07 ` Roger Quadros 2016-06-02 11:07 ` Roger Quadros 2016-05-13 10:03 ` [PATCH v8 14/14] usb: host: xhci-plat: Add otg device to platform data Roger Quadros 2016-05-13 10:03 ` Roger Quadros 2016-05-30 9:29 ` [PATCH v8 00/14] USB OTG/dual-role framework Peter Chen 2016-05-30 9:29 ` Peter Chen 2016-05-30 14:04 ` Roger Quadros 2016-05-30 14:04 ` Roger Quadros 2016-06-08 9:03 [PATCH v9 " Roger Quadros 2016-06-08 9:03 ` [PATCH v9 10/14] usb: otg: add hcd companion support Roger Quadros 2016-06-08 9:03 ` Roger Quadros
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