* [PATCH v2 0/4] usb: xhci: Add debug capability support in xhci
@ 2017-08-07 8:07 Lu Baolu
2017-08-07 8:07 ` [PATCH v2 1/4] usb: xhci: Make some static functions global Lu Baolu
` (3 more replies)
0 siblings, 4 replies; 9+ messages in thread
From: Lu Baolu @ 2017-08-07 8:07 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
Hi,
This series is for xHCI debug capability (spec section 7.6.8) support
in the xHCI driver.
xHCI compatible USB host controllers(i.e. super-speed USB3 controllers)
can be implemented with the Debug Capability(DbC). It presents a debug
device which is fully compliant with the USB framework and provides the
equivalent of a very high performance full-duplex serial link. The debug
capability operation model and registers interface are defined in 7.6.8
of the xHCI specification, revision 1.1.
The DbC debug device shares a root port with the xHCI host. By default,
the debug capability is disabled and the root port is assigned to xHCI.
When the DbC is enabled, the root port will be assigned to the DbC debug
device, and the xHCI sees nothing on this port. This implementation uses
a sysfs node named <dbc> under the xHCI device to manage the enabling
and disabling of the debug capability.
When the debug capability is enabled, it will present a debug device
through the debug port. This debug device is fully compliant with the
USB3 framework, and it can be enumerated by a debug host on the other
end of the USB link. As soon as the debug device is configured, a TTY
serial device named /dev/ttyGSn will be created.
One use of this link is running a login service on the debug target.
Hence it can be remote accessed by a debug host. Another use case can
probably be found in servers. It provides a peer-to-peer USB link
between two host-only machines. This provides a reasonable out-of-band
communication method between two servers.
Best regards,
Lu Baolu
---
Change log:
v1->v2:
- Add a new patch to move u_serial.c from drivers/usb/gadget/function
to drivers/usb/common/ and move u_serial.h to include/linux/usb/.
Lu Baolu (4):
usb: xhci: Make some static functions global
usb: common: Move u_serial from gadget/function to usb/common
usb: xhci: Add DbC support in xHCI driver
usb: doc: Update document for USB3 debug port usage
.../ABI/testing/sysfs-bus-pci-drivers-xhci_hcd | 25 +
Documentation/driver-api/usb/usb3-debug-port.rst | 68 +
drivers/usb/Kconfig | 3 +
drivers/usb/Makefile | 3 +-
drivers/usb/common/Makefile | 1 +
drivers/usb/common/u_serial.c | 1604 +++++++++++++++++++
drivers/usb/gadget/Kconfig | 3 -
drivers/usb/gadget/function/Makefile | 1 -
drivers/usb/gadget/function/f_acm.c | 4 +-
drivers/usb/gadget/function/f_obex.c | 4 +-
drivers/usb/gadget/function/f_serial.c | 3 +-
drivers/usb/gadget/function/u_serial.c | 1606 --------------------
drivers/usb/gadget/function/u_serial.h | 71 -
drivers/usb/gadget/legacy/acm_ms.c | 3 +-
drivers/usb/gadget/legacy/cdc2.c | 2 +-
drivers/usb/gadget/legacy/dbgp.c | 3 +-
drivers/usb/gadget/legacy/multi.c | 2 +-
drivers/usb/gadget/legacy/nokia.c | 2 +-
drivers/usb/gadget/legacy/serial.c | 3 +-
drivers/usb/host/Kconfig | 9 +
drivers/usb/host/Makefile | 5 +
drivers/usb/host/xhci-dbgcap.c | 1100 ++++++++++++++
drivers/usb/host/xhci-dbgcap.h | 194 +++
drivers/usb/host/xhci-mem.c | 94 +-
drivers/usb/host/xhci-ring.c | 4 +-
drivers/usb/host/xhci-trace.h | 65 +
drivers/usb/host/xhci.c | 10 +
drivers/usb/host/xhci.h | 17 +-
include/linux/usb/gadget.h | 52 +
include/linux/usb/u_serial.h | 71 +
30 files changed, 3290 insertions(+), 1742 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd
create mode 100644 drivers/usb/common/u_serial.c
delete mode 100644 drivers/usb/gadget/function/u_serial.c
delete mode 100644 drivers/usb/gadget/function/u_serial.h
create mode 100644 drivers/usb/host/xhci-dbgcap.c
create mode 100644 drivers/usb/host/xhci-dbgcap.h
create mode 100644 include/linux/usb/u_serial.h
--
2.7.4
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v2 1/4] usb: xhci: Make some static functions global
2017-08-07 8:07 [PATCH v2 0/4] usb: xhci: Add debug capability support in xhci Lu Baolu
@ 2017-08-07 8:07 ` Lu Baolu
2017-08-07 8:07 ` [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common Lu Baolu
` (2 subsequent siblings)
3 siblings, 0 replies; 9+ messages in thread
From: Lu Baolu @ 2017-08-07 8:07 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
This patch makes some static functions global to avoid duplications
in different files. These functions can be used in the implementation
of xHCI debug capability. There is no functional change.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/usb/host/xhci-mem.c | 94 ++++++++++++++++++++++++++------------------
drivers/usb/host/xhci-ring.c | 4 +-
drivers/usb/host/xhci.h | 16 +++++++-
3 files changed, 72 insertions(+), 42 deletions(-)
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 2a82c92..1ccb1c5 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -368,7 +368,7 @@ static int xhci_alloc_segments_for_ring(struct xhci_hcd *xhci,
* Set the end flag and the cycle toggle bit on the last segment.
* See section 4.9.1 and figures 15 and 16.
*/
-static struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci,
+struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci,
unsigned int num_segs, unsigned int cycle_state,
enum xhci_ring_type type, unsigned int max_packet, gfp_t flags)
{
@@ -467,7 +467,7 @@ int xhci_ring_expansion(struct xhci_hcd *xhci, struct xhci_ring *ring,
#define CTX_SIZE(_hcc) (HCC_64BYTE_CONTEXT(_hcc) ? 64 : 32)
-static struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
+struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
int type, gfp_t flags)
{
struct xhci_container_ctx *ctx;
@@ -492,7 +492,7 @@ static struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci
return ctx;
}
-static void xhci_free_container_ctx(struct xhci_hcd *xhci,
+void xhci_free_container_ctx(struct xhci_hcd *xhci,
struct xhci_container_ctx *ctx)
{
if (!ctx)
@@ -1762,21 +1762,61 @@ void xhci_free_command(struct xhci_hcd *xhci,
kfree(command);
}
+int xhci_alloc_erst(struct xhci_hcd *xhci,
+ struct xhci_ring *evt_ring,
+ struct xhci_erst *erst,
+ gfp_t flags)
+{
+ size_t size;
+ unsigned int val;
+ struct xhci_segment *seg;
+ struct xhci_erst_entry *entry;
+
+ size = sizeof(struct xhci_erst_entry) * evt_ring->num_segs;
+ erst->entries = dma_alloc_coherent(xhci_to_hcd(xhci)->self.sysdev,
+ size,
+ &erst->erst_dma_addr,
+ flags);
+ if (!erst->entries)
+ return -ENOMEM;
+
+ memset(erst->entries, 0, size);
+ erst->num_entries = evt_ring->num_segs;
+
+ seg = evt_ring->first_seg;
+ for (val = 0; val < evt_ring->num_segs; val++) {
+ entry = &erst->entries[val];
+ entry->seg_addr = cpu_to_le64(seg->dma);
+ entry->seg_size = cpu_to_le32(TRBS_PER_SEGMENT);
+ entry->rsvd = 0;
+ seg = seg->next;
+ }
+
+ return 0;
+}
+
+void xhci_free_erst(struct xhci_hcd *xhci, struct xhci_erst *erst)
+{
+ size_t size;
+ struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
+
+ size = sizeof(struct xhci_erst_entry) * (erst->num_entries);
+ if (erst->entries)
+ dma_free_coherent(dev, size,
+ erst->entries,
+ erst->erst_dma_addr);
+ erst->entries = NULL;
+}
+
void xhci_mem_cleanup(struct xhci_hcd *xhci)
{
struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
- int size;
int i, j, num_ports;
cancel_delayed_work_sync(&xhci->cmd_timer);
- /* Free the Event Ring Segment Table and the actual Event Ring */
- size = sizeof(struct xhci_erst_entry)*(xhci->erst.num_entries);
- if (xhci->erst.entries)
- dma_free_coherent(dev, size,
- xhci->erst.entries, xhci->erst.erst_dma_addr);
- xhci->erst.entries = NULL;
- xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Freed ERST");
+ xhci_free_erst(xhci, &xhci->erst);
+
if (xhci->event_ring)
xhci_ring_free(xhci, xhci->event_ring);
xhci->event_ring = NULL;
@@ -2313,9 +2353,8 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
unsigned int val, val2;
u64 val_64;
- struct xhci_segment *seg;
- u32 page_size, temp;
- int i;
+ u32 page_size, temp;
+ int i, ret;
INIT_LIST_HEAD(&xhci->cmd_list);
@@ -2454,32 +2493,9 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
if (xhci_check_trb_in_td_math(xhci) < 0)
goto fail;
- xhci->erst.entries = dma_alloc_coherent(dev,
- sizeof(struct xhci_erst_entry) * ERST_NUM_SEGS, &dma,
- flags);
- if (!xhci->erst.entries)
+ ret = xhci_alloc_erst(xhci, xhci->event_ring, &xhci->erst, flags);
+ if (ret)
goto fail;
- xhci_dbg_trace(xhci, trace_xhci_dbg_init,
- "// Allocated event ring segment table at 0x%llx",
- (unsigned long long)dma);
-
- memset(xhci->erst.entries, 0, sizeof(struct xhci_erst_entry)*ERST_NUM_SEGS);
- xhci->erst.num_entries = ERST_NUM_SEGS;
- xhci->erst.erst_dma_addr = dma;
- xhci_dbg_trace(xhci, trace_xhci_dbg_init,
- "Set ERST to 0; private num segs = %i, virt addr = %p, dma addr = 0x%llx",
- xhci->erst.num_entries,
- xhci->erst.entries,
- (unsigned long long)xhci->erst.erst_dma_addr);
-
- /* set ring base address and size for each segment table entry */
- for (val = 0, seg = xhci->event_ring->first_seg; val < ERST_NUM_SEGS; val++) {
- struct xhci_erst_entry *entry = &xhci->erst.entries[val];
- entry->seg_addr = cpu_to_le64(seg->dma);
- entry->seg_size = cpu_to_le32(TRBS_PER_SEGMENT);
- entry->rsvd = 0;
- seg = seg->next;
- }
/* set ERST count with the number of entries in the segment table */
val = readl(&xhci->ir_set->erst_size);
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index cc368ad..a55e377 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -165,7 +165,7 @@ static void next_trb(struct xhci_hcd *xhci,
* See Cycle bit rules. SW is the consumer for the event ring only.
* Don't make a ring full of link TRBs. That would be dumb and this would loop.
*/
-static void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring)
+void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring)
{
/* event ring doesn't have link trbs, check for last trb */
if (ring->type == TYPE_EVENT) {
@@ -2961,7 +2961,7 @@ static int prepare_transfer(struct xhci_hcd *xhci,
return 0;
}
-static unsigned int count_trbs(u64 addr, u64 len)
+unsigned int count_trbs(u64 addr, u64 len)
{
unsigned int num_trbs;
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index e3e9352..62bcdcd 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1959,9 +1959,17 @@ void xhci_slot_copy(struct xhci_hcd *xhci,
int xhci_endpoint_init(struct xhci_hcd *xhci, struct xhci_virt_device *virt_dev,
struct usb_device *udev, struct usb_host_endpoint *ep,
gfp_t mem_flags);
+struct xhci_ring *xhci_ring_alloc(struct xhci_hcd *xhci,
+ unsigned int num_segs, unsigned int cycle_state,
+ enum xhci_ring_type type, unsigned int max_packet, gfp_t flags);
void xhci_ring_free(struct xhci_hcd *xhci, struct xhci_ring *ring);
int xhci_ring_expansion(struct xhci_hcd *xhci, struct xhci_ring *ring,
- unsigned int num_trbs, gfp_t flags);
+ unsigned int num_trbs, gfp_t flags);
+int xhci_alloc_erst(struct xhci_hcd *xhci,
+ struct xhci_ring *evt_ring,
+ struct xhci_erst *erst,
+ gfp_t flags);
+void xhci_free_erst(struct xhci_hcd *xhci, struct xhci_erst *erst);
void xhci_free_endpoint_ring(struct xhci_hcd *xhci,
struct xhci_virt_device *virt_dev,
unsigned int ep_index);
@@ -1991,6 +1999,10 @@ struct xhci_command *xhci_alloc_command(struct xhci_hcd *xhci,
void xhci_urb_free_priv(struct urb_priv *urb_priv);
void xhci_free_command(struct xhci_hcd *xhci,
struct xhci_command *command);
+struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
+ int type, gfp_t flags);
+void xhci_free_container_ctx(struct xhci_hcd *xhci,
+ struct xhci_container_ctx *ctx);
/* xHCI host controller glue */
typedef void (*xhci_get_quirks_t)(struct device *, struct xhci_hcd *);
@@ -2065,6 +2077,8 @@ void xhci_handle_command_timeout(struct work_struct *work);
void xhci_ring_ep_doorbell(struct xhci_hcd *xhci, unsigned int slot_id,
unsigned int ep_index, unsigned int stream_id);
void xhci_cleanup_command_queue(struct xhci_hcd *xhci);
+void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring);
+unsigned int count_trbs(u64 addr, u64 len);
/* xHCI roothub code */
void xhci_set_link_state(struct xhci_hcd *xhci, __le32 __iomem **port_array,
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common
2017-08-07 8:07 [PATCH v2 0/4] usb: xhci: Add debug capability support in xhci Lu Baolu
2017-08-07 8:07 ` [PATCH v2 1/4] usb: xhci: Make some static functions global Lu Baolu
@ 2017-08-07 8:07 ` Lu Baolu
2017-08-07 8:13 ` Felipe Balbi
2017-08-07 8:07 ` [PATCH v2 3/4] usb: xhci: Add DbC support in xHCI driver Lu Baolu
2017-08-07 8:07 ` [PATCH v2 4/4] usb: doc: Update document for USB3 debug port usage Lu Baolu
3 siblings, 1 reply; 9+ messages in thread
From: Lu Baolu @ 2017-08-07 8:07 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
The component u_serial provides a glue layer between TTY layer
and a USB gadget device needed to provide a basic serial port
functionality. Currently, u_serial sits under gadget/function
and depends on CONFIG_USB_GADGET to be compiled and used.
Most of the serial gadget devices are based on a UDC (USB device
controller) and implemented by making use of the Linux gadget
frameworks. But we are facing other implementions as well. One
example can be found with xHCI debug capability. The xHCI debug
capability implements a serial gadget with hardware and firmware,
and provides an interface similar with xHCI host for submitting
and reaping the transfer requests.
In order to make better use of u_serial when implementing xHCI
debug capability in xHCI driver, this patch moves u_serial.c
from gadget/function to usb/common, and moves u_serial.h from
gadget/function to include/linux/usb.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/usb/Kconfig | 3 +
drivers/usb/Makefile | 3 +-
drivers/usb/common/Makefile | 1 +
drivers/usb/common/u_serial.c | 1604 +++++++++++++++++++++++++++++++
drivers/usb/gadget/Kconfig | 3 -
drivers/usb/gadget/function/Makefile | 1 -
drivers/usb/gadget/function/f_acm.c | 4 +-
drivers/usb/gadget/function/f_obex.c | 4 +-
drivers/usb/gadget/function/f_serial.c | 3 +-
drivers/usb/gadget/function/u_serial.c | 1606 --------------------------------
drivers/usb/gadget/function/u_serial.h | 71 --
drivers/usb/gadget/legacy/acm_ms.c | 3 +-
drivers/usb/gadget/legacy/cdc2.c | 2 +-
drivers/usb/gadget/legacy/dbgp.c | 3 +-
drivers/usb/gadget/legacy/multi.c | 2 +-
drivers/usb/gadget/legacy/nokia.c | 2 +-
drivers/usb/gadget/legacy/serial.c | 3 +-
include/linux/usb/u_serial.h | 71 ++
18 files changed, 1689 insertions(+), 1700 deletions(-)
create mode 100644 drivers/usb/common/u_serial.c
delete mode 100644 drivers/usb/gadget/function/u_serial.c
delete mode 100644 drivers/usb/gadget/function/u_serial.h
create mode 100644 include/linux/usb/u_serial.h
diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig
index 939a63b..c39aceb 100644
--- a/drivers/usb/Kconfig
+++ b/drivers/usb/Kconfig
@@ -35,6 +35,9 @@ config USB_COMMON
config USB_ARCH_HAS_HCD
def_bool y
+config USB_U_SERIAL
+ tristate
+
config USB
tristate "Support for Host-side USB"
depends on USB_ARCH_HAS_HCD
diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile
index 9650b35..a3274aa 100644
--- a/drivers/usb/Makefile
+++ b/drivers/usb/Makefile
@@ -5,6 +5,7 @@
# Object files in subdirectories
obj-$(CONFIG_USB) += core/
+obj-$(CONFIG_USB_COMMON) += common/
obj-$(CONFIG_USB_SUPPORT) += phy/
obj-$(CONFIG_USB_DWC3) += dwc3/
@@ -59,8 +60,6 @@ obj-$(CONFIG_USB_CHIPIDEA) += chipidea/
obj-$(CONFIG_USB_RENESAS_USBHS) += renesas_usbhs/
obj-$(CONFIG_USB_GADGET) += gadget/
-obj-$(CONFIG_USB_COMMON) += common/
-
obj-$(CONFIG_USBIP_CORE) += usbip/
obj-$(CONFIG_TYPEC) += typec/
diff --git a/drivers/usb/common/Makefile b/drivers/usb/common/Makefile
index 6bbb3ec..dff720b 100644
--- a/drivers/usb/common/Makefile
+++ b/drivers/usb/common/Makefile
@@ -8,3 +8,4 @@ usb-common-$(CONFIG_USB_LED_TRIG) += led.o
obj-$(CONFIG_USB_OTG_FSM) += usb-otg-fsm.o
obj-$(CONFIG_USB_ULPI_BUS) += ulpi.o
+obj-$(CONFIG_USB_U_SERIAL) += u_serial.o
diff --git a/drivers/usb/common/u_serial.c b/drivers/usb/common/u_serial.c
new file mode 100644
index 0000000..da09602
--- /dev/null
+++ b/drivers/usb/common/u_serial.c
@@ -0,0 +1,1604 @@
+/*
+ * u_serial.c - utilities for USB gadget "serial port"/TTY support
+ *
+ * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
+ * Copyright (C) 2008 David Brownell
+ * Copyright (C) 2008 by Nokia Corporation
+ *
+ * This code also borrows from usbserial.c, which is
+ * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
+ * Copyright (C) 2000 Peter Berger (pberger@brimson.com)
+ * Copyright (C) 2000 Al Borchers (alborchers@steinerpoint.com)
+ *
+ * This software is distributed under the terms of the GNU General
+ * Public License ("GPL") as published by the Free Software Foundation,
+ * either version 2 of that License or (at your option) any later version.
+ */
+
+/* #define VERBOSE_DEBUG */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/console.h>
+#include <linux/kthread.h>
+#include <linux/usb/u_serial.h>
+
+/*
+ * This component encapsulates the TTY layer glue needed to provide basic
+ * "serial port" functionality through the USB gadget stack. Each such
+ * port is exposed through a /dev/ttyGS* node.
+ *
+ * After this module has been loaded, the individual TTY port can be requested
+ * (gserial_alloc_line()) and it will stay available until they are removed
+ * (gserial_free_line()). Each one may be connected to a USB function
+ * (gserial_connect), or disconnected (with gserial_disconnect) when the USB
+ * host issues a config change event. Data can only flow when the port is
+ * connected to the host.
+ *
+ * A given TTY port can be made available in multiple configurations.
+ * For example, each one might expose a ttyGS0 node which provides a
+ * login application. In one case that might use CDC ACM interface 0,
+ * while another configuration might use interface 3 for that. The
+ * work to handle that (including descriptor management) is not part
+ * of this component.
+ *
+ * Configurations may expose more than one TTY port. For example, if
+ * ttyGS0 provides login service, then ttyGS1 might provide dialer access
+ * for a telephone or fax link. And ttyGS2 might be something that just
+ * needs a simple byte stream interface for some messaging protocol that
+ * is managed in userspace ... OBEX, PTP, and MTP have been mentioned.
+ *
+ *
+ * gserial is the lifecycle interface, used by USB functions
+ * gs_port is the I/O nexus, used by the tty driver
+ * tty_struct links to the tty/filesystem framework
+ *
+ * gserial <---> gs_port ... links will be null when the USB link is
+ * inactive; managed by gserial_{connect,disconnect}(). each gserial
+ * instance can wrap its own USB control protocol.
+ * gserial->ioport == usb_ep->driver_data ... gs_port
+ * gs_port->port_usb ... gserial
+ *
+ * gs_port <---> tty_struct ... links will be null when the TTY file
+ * isn't opened; managed by gs_open()/gs_close()
+ * gserial->port_tty ... tty_struct
+ * tty_struct->driver_data ... gserial
+ */
+
+/* RX and TX queues can buffer QUEUE_SIZE packets before they hit the
+ * next layer of buffering. For TX that's a circular buffer; for RX
+ * consider it a NOP. A third layer is provided by the TTY code.
+ */
+#define QUEUE_SIZE 16
+#define WRITE_BUF_SIZE 8192 /* TX only */
+#define GS_CONSOLE_BUF_SIZE 8192
+
+/* circular buffer */
+struct gs_buf {
+ unsigned buf_size;
+ char *buf_buf;
+ char *buf_get;
+ char *buf_put;
+};
+
+/* console info */
+struct gscons_info {
+ struct gs_port *port;
+ struct task_struct *console_thread;
+ struct gs_buf con_buf;
+ /* protect the buf and busy flag */
+ spinlock_t con_lock;
+ int req_busy;
+ struct usb_request *console_req;
+};
+
+/*
+ * The port structure holds info for each port, one for each minor number
+ * (and thus for each /dev/ node).
+ */
+struct gs_port {
+ struct tty_port port;
+ spinlock_t port_lock; /* guard port_* access */
+
+ struct gserial *port_usb;
+
+ bool openclose; /* open/close in progress */
+ u8 port_num;
+
+ struct list_head read_pool;
+ int read_started;
+ int read_allocated;
+ struct list_head read_queue;
+ unsigned n_read;
+ struct tasklet_struct push;
+
+ struct list_head write_pool;
+ int write_started;
+ int write_allocated;
+ struct gs_buf port_write_buf;
+ wait_queue_head_t drain_wait; /* wait while writes drain */
+ bool write_busy;
+ wait_queue_head_t close_wait;
+
+ /* REVISIT this state ... */
+ struct usb_cdc_line_coding port_line_coding; /* 8-N-1 etc */
+};
+
+static struct portmaster {
+ struct mutex lock; /* protect open/close */
+ struct gs_port *port;
+} ports[MAX_U_SERIAL_PORTS];
+
+#define GS_CLOSE_TIMEOUT 15 /* seconds */
+
+
+
+#ifdef VERBOSE_DEBUG
+#ifndef pr_vdebug
+#define pr_vdebug(fmt, arg...) \
+ pr_debug(fmt, ##arg)
+#endif /* pr_vdebug */
+#else
+#ifndef pr_vdebug
+#define pr_vdebug(fmt, arg...) \
+ ({ if (0) pr_debug(fmt, ##arg); })
+#endif /* pr_vdebug */
+#endif
+
+/*-------------------------------------------------------------------------*/
+
+/* Circular Buffer */
+
+/*
+ * gs_buf_alloc
+ *
+ * Allocate a circular buffer and all associated memory.
+ */
+static int gs_buf_alloc(struct gs_buf *gb, unsigned size)
+{
+ gb->buf_buf = kmalloc(size, GFP_KERNEL);
+ if (gb->buf_buf == NULL)
+ return -ENOMEM;
+
+ gb->buf_size = size;
+ gb->buf_put = gb->buf_buf;
+ gb->buf_get = gb->buf_buf;
+
+ return 0;
+}
+
+/*
+ * gs_buf_free
+ *
+ * Free the buffer and all associated memory.
+ */
+static void gs_buf_free(struct gs_buf *gb)
+{
+ kfree(gb->buf_buf);
+ gb->buf_buf = NULL;
+}
+
+/*
+ * gs_buf_clear
+ *
+ * Clear out all data in the circular buffer.
+ */
+static void gs_buf_clear(struct gs_buf *gb)
+{
+ gb->buf_get = gb->buf_put;
+ /* equivalent to a get of all data available */
+}
+
+/*
+ * gs_buf_data_avail
+ *
+ * Return the number of bytes of data written into the circular
+ * buffer.
+ */
+static unsigned gs_buf_data_avail(struct gs_buf *gb)
+{
+ return (gb->buf_size + gb->buf_put - gb->buf_get) % gb->buf_size;
+}
+
+/*
+ * gs_buf_space_avail
+ *
+ * Return the number of bytes of space available in the circular
+ * buffer.
+ */
+static unsigned gs_buf_space_avail(struct gs_buf *gb)
+{
+ return (gb->buf_size + gb->buf_get - gb->buf_put - 1) % gb->buf_size;
+}
+
+/*
+ * gs_buf_put
+ *
+ * Copy data data from a user buffer and put it into the circular buffer.
+ * Restrict to the amount of space available.
+ *
+ * Return the number of bytes copied.
+ */
+static unsigned
+gs_buf_put(struct gs_buf *gb, const char *buf, unsigned count)
+{
+ unsigned len;
+
+ len = gs_buf_space_avail(gb);
+ if (count > len)
+ count = len;
+
+ if (count == 0)
+ return 0;
+
+ len = gb->buf_buf + gb->buf_size - gb->buf_put;
+ if (count > len) {
+ memcpy(gb->buf_put, buf, len);
+ memcpy(gb->buf_buf, buf+len, count - len);
+ gb->buf_put = gb->buf_buf + count - len;
+ } else {
+ memcpy(gb->buf_put, buf, count);
+ if (count < len)
+ gb->buf_put += count;
+ else /* count == len */
+ gb->buf_put = gb->buf_buf;
+ }
+
+ return count;
+}
+
+/*
+ * gs_buf_get
+ *
+ * Get data from the circular buffer and copy to the given buffer.
+ * Restrict to the amount of data available.
+ *
+ * Return the number of bytes copied.
+ */
+static unsigned
+gs_buf_get(struct gs_buf *gb, char *buf, unsigned count)
+{
+ unsigned len;
+
+ len = gs_buf_data_avail(gb);
+ if (count > len)
+ count = len;
+
+ if (count == 0)
+ return 0;
+
+ len = gb->buf_buf + gb->buf_size - gb->buf_get;
+ if (count > len) {
+ memcpy(buf, gb->buf_get, len);
+ memcpy(buf+len, gb->buf_buf, count - len);
+ gb->buf_get = gb->buf_buf + count - len;
+ } else {
+ memcpy(buf, gb->buf_get, count);
+ if (count < len)
+ gb->buf_get += count;
+ else /* count == len */
+ gb->buf_get = gb->buf_buf;
+ }
+
+ return count;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* I/O glue between TTY (upper) and USB function (lower) driver layers */
+
+/*
+ * gs_alloc_req
+ *
+ * Allocate a usb_request and its buffer. Returns a pointer to the
+ * usb_request or NULL if there is an error.
+ */
+struct usb_request *
+gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t kmalloc_flags)
+{
+ struct usb_request *req;
+
+ req = usb_ep_alloc_request(ep, kmalloc_flags);
+
+ if (req != NULL) {
+ req->length = len;
+ req->buf = kmalloc(len, kmalloc_flags);
+ if (req->buf == NULL) {
+ usb_ep_free_request(ep, req);
+ return NULL;
+ }
+ }
+
+ return req;
+}
+EXPORT_SYMBOL_GPL(gs_alloc_req);
+
+/*
+ * gs_free_req
+ *
+ * Free a usb_request and its buffer.
+ */
+void gs_free_req(struct usb_ep *ep, struct usb_request *req)
+{
+ kfree(req->buf);
+ usb_ep_free_request(ep, req);
+}
+EXPORT_SYMBOL_GPL(gs_free_req);
+
+/*
+ * gs_send_packet
+ *
+ * If there is data to send, a packet is built in the given
+ * buffer and the size is returned. If there is no data to
+ * send, 0 is returned.
+ *
+ * Called with port_lock held.
+ */
+static unsigned
+gs_send_packet(struct gs_port *port, char *packet, unsigned size)
+{
+ unsigned len;
+
+ len = gs_buf_data_avail(&port->port_write_buf);
+ if (len < size)
+ size = len;
+ if (size != 0)
+ size = gs_buf_get(&port->port_write_buf, packet, size);
+ return size;
+}
+
+/*
+ * gs_start_tx
+ *
+ * This function finds available write requests, calls
+ * gs_send_packet to fill these packets with data, and
+ * continues until either there are no more write requests
+ * available or no more data to send. This function is
+ * run whenever data arrives or write requests are available.
+ *
+ * Context: caller owns port_lock; port_usb is non-null.
+ */
+static int gs_start_tx(struct gs_port *port)
+/*
+__releases(&port->port_lock)
+__acquires(&port->port_lock)
+*/
+{
+ struct list_head *pool = &port->write_pool;
+ struct usb_ep *in;
+ int status = 0;
+ bool do_tty_wake = false;
+
+ if (!port->port_usb)
+ return status;
+
+ in = port->port_usb->in;
+
+ while (!port->write_busy && !list_empty(pool)) {
+ struct usb_request *req;
+ int len;
+
+ if (port->write_started >= QUEUE_SIZE)
+ break;
+
+ req = list_entry(pool->next, struct usb_request, list);
+ len = gs_send_packet(port, req->buf, in->maxpacket);
+ if (len == 0) {
+ wake_up_interruptible(&port->drain_wait);
+ break;
+ }
+ do_tty_wake = true;
+
+ req->length = len;
+ list_del(&req->list);
+ req->zero = (gs_buf_data_avail(&port->port_write_buf) == 0);
+
+ pr_vdebug("ttyGS%d: tx len=%d, 0x%02x 0x%02x 0x%02x ...\n",
+ port->port_num, len, *((u8 *)req->buf),
+ *((u8 *)req->buf+1), *((u8 *)req->buf+2));
+
+ /* Drop lock while we call out of driver; completions
+ * could be issued while we do so. Disconnection may
+ * happen too; maybe immediately before we queue this!
+ *
+ * NOTE that we may keep sending data for a while after
+ * the TTY closed (dev->ioport->port_tty is NULL).
+ */
+ port->write_busy = true;
+ spin_unlock(&port->port_lock);
+ status = usb_ep_queue(in, req, GFP_ATOMIC);
+ spin_lock(&port->port_lock);
+ port->write_busy = false;
+
+ if (status) {
+ pr_debug("%s: %s %s err %d\n",
+ __func__, "queue", in->name, status);
+ list_add(&req->list, pool);
+ break;
+ }
+
+ port->write_started++;
+
+ /* abort immediately after disconnect */
+ if (!port->port_usb)
+ break;
+ }
+
+ if (do_tty_wake && port->port.tty)
+ tty_wakeup(port->port.tty);
+ return status;
+}
+
+/*
+ * Context: caller owns port_lock, and port_usb is set
+ */
+static unsigned gs_start_rx(struct gs_port *port)
+/*
+__releases(&port->port_lock)
+__acquires(&port->port_lock)
+*/
+{
+ struct list_head *pool = &port->read_pool;
+ struct usb_ep *out = port->port_usb->out;
+
+ while (!list_empty(pool)) {
+ struct usb_request *req;
+ int status;
+ struct tty_struct *tty;
+
+ /* no more rx if closed */
+ tty = port->port.tty;
+ if (!tty)
+ break;
+
+ if (port->read_started >= QUEUE_SIZE)
+ break;
+
+ req = list_entry(pool->next, struct usb_request, list);
+ list_del(&req->list);
+ req->length = out->maxpacket;
+
+ /* drop lock while we call out; the controller driver
+ * may need to call us back (e.g. for disconnect)
+ */
+ spin_unlock(&port->port_lock);
+ status = usb_ep_queue(out, req, GFP_ATOMIC);
+ spin_lock(&port->port_lock);
+
+ if (status) {
+ pr_debug("%s: %s %s err %d\n",
+ __func__, "queue", out->name, status);
+ list_add(&req->list, pool);
+ break;
+ }
+ port->read_started++;
+
+ /* abort immediately after disconnect */
+ if (!port->port_usb)
+ break;
+ }
+ return port->read_started;
+}
+
+/*
+ * RX tasklet takes data out of the RX queue and hands it up to the TTY
+ * layer until it refuses to take any more data (or is throttled back).
+ * Then it issues reads for any further data.
+ *
+ * If the RX queue becomes full enough that no usb_request is queued,
+ * the OUT endpoint may begin NAKing as soon as its FIFO fills up.
+ * So QUEUE_SIZE packets plus however many the FIFO holds (usually two)
+ * can be buffered before the TTY layer's buffers (currently 64 KB).
+ */
+static void gs_rx_push(unsigned long _port)
+{
+ struct gs_port *port = (void *)_port;
+ struct tty_struct *tty;
+ struct list_head *queue = &port->read_queue;
+ bool disconnect = false;
+ bool do_push = false;
+
+ /* hand any queued data to the tty */
+ spin_lock_irq(&port->port_lock);
+ tty = port->port.tty;
+ while (!list_empty(queue)) {
+ struct usb_request *req;
+
+ req = list_first_entry(queue, struct usb_request, list);
+
+ /* leave data queued if tty was rx throttled */
+ if (tty && tty_throttled(tty))
+ break;
+
+ switch (req->status) {
+ case -ESHUTDOWN:
+ disconnect = true;
+ pr_vdebug("ttyGS%d: shutdown\n", port->port_num);
+ break;
+
+ default:
+ /* presumably a transient fault */
+ pr_warn("ttyGS%d: unexpected RX status %d\n",
+ port->port_num, req->status);
+ /* FALLTHROUGH */
+ case 0:
+ /* normal completion */
+ break;
+ }
+
+ /* push data to (open) tty */
+ if (req->actual) {
+ char *packet = req->buf;
+ unsigned size = req->actual;
+ unsigned n;
+ int count;
+
+ /* we may have pushed part of this packet already... */
+ n = port->n_read;
+ if (n) {
+ packet += n;
+ size -= n;
+ }
+
+ count = tty_insert_flip_string(&port->port, packet,
+ size);
+ if (count)
+ do_push = true;
+ if (count != size) {
+ /* stop pushing; TTY layer can't handle more */
+ port->n_read += count;
+ pr_vdebug("ttyGS%d: rx block %d/%d\n",
+ port->port_num, count, req->actual);
+ break;
+ }
+ port->n_read = 0;
+ }
+
+ list_move(&req->list, &port->read_pool);
+ port->read_started--;
+ }
+
+ /* Push from tty to ldisc; this is handled by a workqueue,
+ * so we won't get callbacks and can hold port_lock
+ */
+ if (do_push)
+ tty_flip_buffer_push(&port->port);
+
+
+ /* We want our data queue to become empty ASAP, keeping data
+ * in the tty and ldisc (not here). If we couldn't push any
+ * this time around, there may be trouble unless there's an
+ * implicit tty_unthrottle() call on its way...
+ *
+ * REVISIT we should probably add a timer to keep the tasklet
+ * from starving ... but it's not clear that case ever happens.
+ */
+ if (!list_empty(queue) && tty) {
+ if (!tty_throttled(tty)) {
+ if (do_push)
+ tasklet_schedule(&port->push);
+ else
+ pr_warn("ttyGS%d: RX not scheduled?\n",
+ port->port_num);
+ }
+ }
+
+ /* If we're still connected, refill the USB RX queue. */
+ if (!disconnect && port->port_usb)
+ gs_start_rx(port);
+
+ spin_unlock_irq(&port->port_lock);
+}
+
+static void gs_read_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct gs_port *port = ep->driver_data;
+
+ /* Queue all received data until the tty layer is ready for it. */
+ spin_lock(&port->port_lock);
+ list_add_tail(&req->list, &port->read_queue);
+ tasklet_schedule(&port->push);
+ spin_unlock(&port->port_lock);
+}
+
+static void gs_write_complete(struct usb_ep *ep, struct usb_request *req)
+{
+ struct gs_port *port = ep->driver_data;
+
+ spin_lock(&port->port_lock);
+ list_add(&req->list, &port->write_pool);
+ port->write_started--;
+
+ switch (req->status) {
+ default:
+ /* presumably a transient fault */
+ pr_warn("%s: unexpected %s status %d\n",
+ __func__, ep->name, req->status);
+ /* FALL THROUGH */
+ case 0:
+ /* normal completion */
+ gs_start_tx(port);
+ break;
+
+ case -ESHUTDOWN:
+ /* disconnect */
+ pr_vdebug("%s: %s shutdown\n", __func__, ep->name);
+ break;
+ }
+
+ spin_unlock(&port->port_lock);
+}
+
+static void gs_free_requests(struct usb_ep *ep, struct list_head *head,
+ int *allocated)
+{
+ struct usb_request *req;
+
+ while (!list_empty(head)) {
+ req = list_entry(head->next, struct usb_request, list);
+ list_del(&req->list);
+ gs_free_req(ep, req);
+ if (allocated)
+ (*allocated)--;
+ }
+}
+
+static int gs_alloc_requests(struct usb_ep *ep, struct list_head *head,
+ void (*fn)(struct usb_ep *, struct usb_request *),
+ int *allocated)
+{
+ int i;
+ struct usb_request *req;
+ int n = allocated ? QUEUE_SIZE - *allocated : QUEUE_SIZE;
+
+ /* Pre-allocate up to QUEUE_SIZE transfers, but if we can't
+ * do quite that many this time, don't fail ... we just won't
+ * be as speedy as we might otherwise be.
+ */
+ for (i = 0; i < n; i++) {
+ req = gs_alloc_req(ep, ep->maxpacket, GFP_ATOMIC);
+ if (!req)
+ return list_empty(head) ? -ENOMEM : 0;
+ req->complete = fn;
+ list_add_tail(&req->list, head);
+ if (allocated)
+ (*allocated)++;
+ }
+ return 0;
+}
+
+/**
+ * gs_start_io - start USB I/O streams
+ * @dev: encapsulates endpoints to use
+ * Context: holding port_lock; port_tty and port_usb are non-null
+ *
+ * We only start I/O when something is connected to both sides of
+ * this port. If nothing is listening on the host side, we may
+ * be pointlessly filling up our TX buffers and FIFO.
+ */
+static int gs_start_io(struct gs_port *port)
+{
+ struct list_head *head = &port->read_pool;
+ struct usb_ep *ep = port->port_usb->out;
+ int status;
+ unsigned started;
+
+ /* Allocate RX and TX I/O buffers. We can't easily do this much
+ * earlier (with GFP_KERNEL) because the requests are coupled to
+ * endpoints, as are the packet sizes we'll be using. Different
+ * configurations may use different endpoints with a given port;
+ * and high speed vs full speed changes packet sizes too.
+ */
+ status = gs_alloc_requests(ep, head, gs_read_complete,
+ &port->read_allocated);
+ if (status)
+ return status;
+
+ status = gs_alloc_requests(port->port_usb->in, &port->write_pool,
+ gs_write_complete, &port->write_allocated);
+ if (status) {
+ gs_free_requests(ep, head, &port->read_allocated);
+ return status;
+ }
+
+ /* queue read requests */
+ port->n_read = 0;
+ started = gs_start_rx(port);
+
+ /* unblock any pending writes into our circular buffer */
+ if (started) {
+ tty_wakeup(port->port.tty);
+ } else {
+ gs_free_requests(ep, head, &port->read_allocated);
+ gs_free_requests(port->port_usb->in, &port->write_pool,
+ &port->write_allocated);
+ status = -EIO;
+ }
+
+ return status;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* TTY Driver */
+
+/*
+ * gs_open sets up the link between a gs_port and its associated TTY.
+ * That link is broken *only* by TTY close(), and all driver methods
+ * know that.
+ */
+static int gs_open(struct tty_struct *tty, struct file *file)
+{
+ int port_num = tty->index;
+ struct gs_port *port;
+ int status;
+
+ do {
+ mutex_lock(&ports[port_num].lock);
+ port = ports[port_num].port;
+ if (!port)
+ status = -ENODEV;
+ else {
+ spin_lock_irq(&port->port_lock);
+
+ /* already open? Great. */
+ if (port->port.count) {
+ status = 0;
+ port->port.count++;
+
+ /* currently opening/closing? wait ... */
+ } else if (port->openclose) {
+ status = -EBUSY;
+
+ /* ... else we do the work */
+ } else {
+ status = -EAGAIN;
+ port->openclose = true;
+ }
+ spin_unlock_irq(&port->port_lock);
+ }
+ mutex_unlock(&ports[port_num].lock);
+
+ switch (status) {
+ default:
+ /* fully handled */
+ return status;
+ case -EAGAIN:
+ /* must do the work */
+ break;
+ case -EBUSY:
+ /* wait for EAGAIN task to finish */
+ msleep(1);
+ /* REVISIT could have a waitchannel here, if
+ * concurrent open performance is important
+ */
+ break;
+ }
+ } while (status != -EAGAIN);
+
+ /* Do the "real open" */
+ spin_lock_irq(&port->port_lock);
+
+ /* allocate circular buffer on first open */
+ if (port->port_write_buf.buf_buf == NULL) {
+
+ spin_unlock_irq(&port->port_lock);
+ status = gs_buf_alloc(&port->port_write_buf, WRITE_BUF_SIZE);
+ spin_lock_irq(&port->port_lock);
+
+ if (status) {
+ pr_debug("gs_open: ttyGS%d (%p,%p) no buffer\n",
+ port->port_num, tty, file);
+ port->openclose = false;
+ goto exit_unlock_port;
+ }
+ }
+
+ /* REVISIT if REMOVED (ports[].port NULL), abort the open
+ * to let rmmod work faster (but this way isn't wrong).
+ */
+
+ /* REVISIT maybe wait for "carrier detect" */
+
+ tty->driver_data = port;
+ port->port.tty = tty;
+
+ port->port.count = 1;
+ port->openclose = false;
+
+ /* if connected, start the I/O stream */
+ if (port->port_usb) {
+ struct gserial *gser = port->port_usb;
+
+ pr_debug("gs_open: start ttyGS%d\n", port->port_num);
+ gs_start_io(port);
+
+ if (gser->connect)
+ gser->connect(gser);
+ }
+
+ pr_debug("gs_open: ttyGS%d (%p,%p)\n", port->port_num, tty, file);
+
+ status = 0;
+
+exit_unlock_port:
+ spin_unlock_irq(&port->port_lock);
+ return status;
+}
+
+static int gs_writes_finished(struct gs_port *p)
+{
+ int cond;
+
+ /* return true on disconnect or empty buffer */
+ spin_lock_irq(&p->port_lock);
+ cond = (p->port_usb == NULL) || !gs_buf_data_avail(&p->port_write_buf);
+ spin_unlock_irq(&p->port_lock);
+
+ return cond;
+}
+
+static void gs_close(struct tty_struct *tty, struct file *file)
+{
+ struct gs_port *port = tty->driver_data;
+ struct gserial *gser;
+
+ spin_lock_irq(&port->port_lock);
+
+ if (port->port.count != 1) {
+ if (port->port.count == 0)
+ WARN_ON(1);
+ else
+ --port->port.count;
+ goto exit;
+ }
+
+ pr_debug("gs_close: ttyGS%d (%p,%p) ...\n", port->port_num, tty, file);
+
+ /* mark port as closing but in use; we can drop port lock
+ * and sleep if necessary
+ */
+ port->openclose = true;
+ port->port.count = 0;
+
+ gser = port->port_usb;
+ if (gser && gser->disconnect)
+ gser->disconnect(gser);
+
+ /* wait for circular write buffer to drain, disconnect, or at
+ * most GS_CLOSE_TIMEOUT seconds; then discard the rest
+ */
+ if (gs_buf_data_avail(&port->port_write_buf) > 0 && gser) {
+ spin_unlock_irq(&port->port_lock);
+ wait_event_interruptible_timeout(port->drain_wait,
+ gs_writes_finished(port),
+ GS_CLOSE_TIMEOUT * HZ);
+ spin_lock_irq(&port->port_lock);
+ gser = port->port_usb;
+ }
+
+ /* Iff we're disconnected, there can be no I/O in flight so it's
+ * ok to free the circular buffer; else just scrub it. And don't
+ * let the push tasklet fire again until we're re-opened.
+ */
+ if (gser == NULL)
+ gs_buf_free(&port->port_write_buf);
+ else
+ gs_buf_clear(&port->port_write_buf);
+
+ port->port.tty = NULL;
+
+ port->openclose = false;
+
+ pr_debug("gs_close: ttyGS%d (%p,%p) done!\n",
+ port->port_num, tty, file);
+
+ wake_up(&port->close_wait);
+exit:
+ spin_unlock_irq(&port->port_lock);
+}
+
+static int gs_write(struct tty_struct *tty, const unsigned char *buf, int count)
+{
+ struct gs_port *port = tty->driver_data;
+ unsigned long flags;
+
+ pr_vdebug("gs_write: ttyGS%d (%p) writing %d bytes\n",
+ port->port_num, tty, count);
+
+ spin_lock_irqsave(&port->port_lock, flags);
+ if (count)
+ count = gs_buf_put(&port->port_write_buf, buf, count);
+ /* treat count == 0 as flush_chars() */
+ if (port->port_usb)
+ gs_start_tx(port);
+ spin_unlock_irqrestore(&port->port_lock, flags);
+
+ return count;
+}
+
+static int gs_put_char(struct tty_struct *tty, unsigned char ch)
+{
+ struct gs_port *port = tty->driver_data;
+ unsigned long flags;
+ int status;
+
+ pr_vdebug("gs_put_char: (%d,%p) char=0x%x, called from %ps\n",
+ port->port_num, tty, ch, __builtin_return_address(0));
+
+ spin_lock_irqsave(&port->port_lock, flags);
+ status = gs_buf_put(&port->port_write_buf, &ch, 1);
+ spin_unlock_irqrestore(&port->port_lock, flags);
+
+ return status;
+}
+
+static void gs_flush_chars(struct tty_struct *tty)
+{
+ struct gs_port *port = tty->driver_data;
+ unsigned long flags;
+
+ pr_vdebug("gs_flush_chars: (%d,%p)\n", port->port_num, tty);
+
+ spin_lock_irqsave(&port->port_lock, flags);
+ if (port->port_usb)
+ gs_start_tx(port);
+ spin_unlock_irqrestore(&port->port_lock, flags);
+}
+
+static int gs_write_room(struct tty_struct *tty)
+{
+ struct gs_port *port = tty->driver_data;
+ unsigned long flags;
+ int room = 0;
+
+ spin_lock_irqsave(&port->port_lock, flags);
+ if (port->port_usb)
+ room = gs_buf_space_avail(&port->port_write_buf);
+ spin_unlock_irqrestore(&port->port_lock, flags);
+
+ pr_vdebug("gs_write_room: (%d,%p) room=%d\n",
+ port->port_num, tty, room);
+
+ return room;
+}
+
+static int gs_chars_in_buffer(struct tty_struct *tty)
+{
+ struct gs_port *port = tty->driver_data;
+ unsigned long flags;
+ int chars = 0;
+
+ spin_lock_irqsave(&port->port_lock, flags);
+ chars = gs_buf_data_avail(&port->port_write_buf);
+ spin_unlock_irqrestore(&port->port_lock, flags);
+
+ pr_vdebug("gs_chars_in_buffer: (%d,%p) chars=%d\n",
+ port->port_num, tty, chars);
+
+ return chars;
+}
+
+/* undo side effects of setting TTY_THROTTLED */
+static void gs_unthrottle(struct tty_struct *tty)
+{
+ struct gs_port *port = tty->driver_data;
+ unsigned long flags;
+
+ spin_lock_irqsave(&port->port_lock, flags);
+ if (port->port_usb) {
+ /* Kickstart read queue processing. We don't do xon/xoff,
+ * rts/cts, or other handshaking with the host, but if the
+ * read queue backs up enough we'll be NAKing OUT packets.
+ */
+ tasklet_schedule(&port->push);
+ pr_vdebug("ttyGS%d: unthrottle\n", port->port_num);
+ }
+ spin_unlock_irqrestore(&port->port_lock, flags);
+}
+
+static int gs_break_ctl(struct tty_struct *tty, int duration)
+{
+ struct gs_port *port = tty->driver_data;
+ int status = 0;
+ struct gserial *gser;
+
+ pr_vdebug("gs_break_ctl: ttyGS%d, send break (%d) \n",
+ port->port_num, duration);
+
+ spin_lock_irq(&port->port_lock);
+ gser = port->port_usb;
+ if (gser && gser->send_break)
+ status = gser->send_break(gser, duration);
+ spin_unlock_irq(&port->port_lock);
+
+ return status;
+}
+
+static const struct tty_operations gs_tty_ops = {
+ .open = gs_open,
+ .close = gs_close,
+ .write = gs_write,
+ .put_char = gs_put_char,
+ .flush_chars = gs_flush_chars,
+ .write_room = gs_write_room,
+ .chars_in_buffer = gs_chars_in_buffer,
+ .unthrottle = gs_unthrottle,
+ .break_ctl = gs_break_ctl,
+};
+
+/*-------------------------------------------------------------------------*/
+
+static struct tty_driver *gs_tty_driver;
+
+#ifdef CONFIG_U_SERIAL_CONSOLE
+
+static struct gscons_info gscons_info;
+static struct console gserial_cons;
+
+static struct usb_request *gs_request_new(struct usb_ep *ep)
+{
+ struct usb_request *req = usb_ep_alloc_request(ep, GFP_ATOMIC);
+ if (!req)
+ return NULL;
+
+ req->buf = kmalloc(ep->maxpacket, GFP_ATOMIC);
+ if (!req->buf) {
+ usb_ep_free_request(ep, req);
+ return NULL;
+ }
+
+ return req;
+}
+
+static void gs_request_free(struct usb_request *req, struct usb_ep *ep)
+{
+ if (!req)
+ return;
+
+ kfree(req->buf);
+ usb_ep_free_request(ep, req);
+}
+
+static void gs_complete_out(struct usb_ep *ep, struct usb_request *req)
+{
+ struct gscons_info *info = &gscons_info;
+
+ switch (req->status) {
+ default:
+ pr_warn("%s: unexpected %s status %d\n",
+ __func__, ep->name, req->status);
+ case 0:
+ /* normal completion */
+ spin_lock(&info->con_lock);
+ info->req_busy = 0;
+ spin_unlock(&info->con_lock);
+
+ wake_up_process(info->console_thread);
+ break;
+ case -ESHUTDOWN:
+ /* disconnect */
+ pr_vdebug("%s: %s shutdown\n", __func__, ep->name);
+ break;
+ }
+}
+
+static int gs_console_connect(int port_num)
+{
+ struct gscons_info *info = &gscons_info;
+ struct gs_port *port;
+ struct usb_ep *ep;
+
+ if (port_num != gserial_cons.index) {
+ pr_err("%s: port num [%d] is not support console\n",
+ __func__, port_num);
+ return -ENXIO;
+ }
+
+ port = ports[port_num].port;
+ ep = port->port_usb->in;
+ if (!info->console_req) {
+ info->console_req = gs_request_new(ep);
+ if (!info->console_req)
+ return -ENOMEM;
+ info->console_req->complete = gs_complete_out;
+ }
+
+ info->port = port;
+ spin_lock(&info->con_lock);
+ info->req_busy = 0;
+ spin_unlock(&info->con_lock);
+ pr_vdebug("port[%d] console connect!\n", port_num);
+ return 0;
+}
+
+static void gs_console_disconnect(struct usb_ep *ep)
+{
+ struct gscons_info *info = &gscons_info;
+ struct usb_request *req = info->console_req;
+
+ gs_request_free(req, ep);
+ info->console_req = NULL;
+}
+
+static int gs_console_thread(void *data)
+{
+ struct gscons_info *info = &gscons_info;
+ struct gs_port *port;
+ struct usb_request *req;
+ struct usb_ep *ep;
+ int xfer, ret, count, size;
+
+ do {
+ port = info->port;
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (!port || !port->port_usb
+ || !port->port_usb->in || !info->console_req)
+ goto sched;
+
+ req = info->console_req;
+ ep = port->port_usb->in;
+
+ spin_lock_irq(&info->con_lock);
+ count = gs_buf_data_avail(&info->con_buf);
+ size = ep->maxpacket;
+
+ if (count > 0 && !info->req_busy) {
+ set_current_state(TASK_RUNNING);
+ if (count < size)
+ size = count;
+
+ xfer = gs_buf_get(&info->con_buf, req->buf, size);
+ req->length = xfer;
+
+ spin_unlock(&info->con_lock);
+ ret = usb_ep_queue(ep, req, GFP_ATOMIC);
+ spin_lock(&info->con_lock);
+ if (ret < 0)
+ info->req_busy = 0;
+ else
+ info->req_busy = 1;
+
+ spin_unlock_irq(&info->con_lock);
+ } else {
+ spin_unlock_irq(&info->con_lock);
+sched:
+ if (kthread_should_stop()) {
+ set_current_state(TASK_RUNNING);
+ break;
+ }
+ schedule();
+ }
+ } while (1);
+
+ return 0;
+}
+
+static int gs_console_setup(struct console *co, char *options)
+{
+ struct gscons_info *info = &gscons_info;
+ int status;
+
+ info->port = NULL;
+ info->console_req = NULL;
+ info->req_busy = 0;
+ spin_lock_init(&info->con_lock);
+
+ status = gs_buf_alloc(&info->con_buf, GS_CONSOLE_BUF_SIZE);
+ if (status) {
+ pr_err("%s: allocate console buffer failed\n", __func__);
+ return status;
+ }
+
+ info->console_thread = kthread_create(gs_console_thread,
+ co, "gs_console");
+ if (IS_ERR(info->console_thread)) {
+ pr_err("%s: cannot create console thread\n", __func__);
+ gs_buf_free(&info->con_buf);
+ return PTR_ERR(info->console_thread);
+ }
+ wake_up_process(info->console_thread);
+
+ return 0;
+}
+
+static void gs_console_write(struct console *co,
+ const char *buf, unsigned count)
+{
+ struct gscons_info *info = &gscons_info;
+ unsigned long flags;
+
+ spin_lock_irqsave(&info->con_lock, flags);
+ gs_buf_put(&info->con_buf, buf, count);
+ spin_unlock_irqrestore(&info->con_lock, flags);
+
+ wake_up_process(info->console_thread);
+}
+
+static struct tty_driver *gs_console_device(struct console *co, int *index)
+{
+ struct tty_driver **p = (struct tty_driver **)co->data;
+
+ if (!*p)
+ return NULL;
+
+ *index = co->index;
+ return *p;
+}
+
+static struct console gserial_cons = {
+ .name = "ttyGS",
+ .write = gs_console_write,
+ .device = gs_console_device,
+ .setup = gs_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = -1,
+ .data = &gs_tty_driver,
+};
+
+static void gserial_console_init(void)
+{
+ register_console(&gserial_cons);
+}
+
+static void gserial_console_exit(void)
+{
+ struct gscons_info *info = &gscons_info;
+
+ unregister_console(&gserial_cons);
+ if (!IS_ERR_OR_NULL(info->console_thread))
+ kthread_stop(info->console_thread);
+ gs_buf_free(&info->con_buf);
+}
+
+#else
+
+static int gs_console_connect(int port_num)
+{
+ return 0;
+}
+
+static void gs_console_disconnect(struct usb_ep *ep)
+{
+}
+
+static void gserial_console_init(void)
+{
+}
+
+static void gserial_console_exit(void)
+{
+}
+
+#endif
+
+static int
+gs_port_alloc(unsigned port_num, struct usb_cdc_line_coding *coding)
+{
+ struct gs_port *port;
+ int ret = 0;
+
+ mutex_lock(&ports[port_num].lock);
+ if (ports[port_num].port) {
+ ret = -EBUSY;
+ goto out;
+ }
+
+ port = kzalloc(sizeof(struct gs_port), GFP_KERNEL);
+ if (port == NULL) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ tty_port_init(&port->port);
+ spin_lock_init(&port->port_lock);
+ init_waitqueue_head(&port->drain_wait);
+ init_waitqueue_head(&port->close_wait);
+
+ tasklet_init(&port->push, gs_rx_push, (unsigned long) port);
+
+ INIT_LIST_HEAD(&port->read_pool);
+ INIT_LIST_HEAD(&port->read_queue);
+ INIT_LIST_HEAD(&port->write_pool);
+
+ port->port_num = port_num;
+ port->port_line_coding = *coding;
+
+ ports[port_num].port = port;
+out:
+ mutex_unlock(&ports[port_num].lock);
+ return ret;
+}
+
+static int gs_closed(struct gs_port *port)
+{
+ int cond;
+
+ spin_lock_irq(&port->port_lock);
+ cond = (port->port.count == 0) && !port->openclose;
+ spin_unlock_irq(&port->port_lock);
+ return cond;
+}
+
+static void gserial_free_port(struct gs_port *port)
+{
+ tasklet_kill(&port->push);
+ /* wait for old opens to finish */
+ wait_event(port->close_wait, gs_closed(port));
+ WARN_ON(port->port_usb != NULL);
+ tty_port_destroy(&port->port);
+ kfree(port);
+}
+
+void gserial_free_line(unsigned char port_num)
+{
+ struct gs_port *port;
+
+ mutex_lock(&ports[port_num].lock);
+ if (WARN_ON(!ports[port_num].port)) {
+ mutex_unlock(&ports[port_num].lock);
+ return;
+ }
+ port = ports[port_num].port;
+ ports[port_num].port = NULL;
+ mutex_unlock(&ports[port_num].lock);
+
+ gserial_free_port(port);
+ tty_unregister_device(gs_tty_driver, port_num);
+ gserial_console_exit();
+}
+EXPORT_SYMBOL_GPL(gserial_free_line);
+
+int gserial_alloc_line(unsigned char *line_num)
+{
+ struct usb_cdc_line_coding coding;
+ struct device *tty_dev;
+ int ret;
+ int port_num;
+
+ coding.dwDTERate = cpu_to_le32(9600);
+ coding.bCharFormat = 8;
+ coding.bParityType = USB_CDC_NO_PARITY;
+ coding.bDataBits = USB_CDC_1_STOP_BITS;
+
+ for (port_num = 0; port_num < MAX_U_SERIAL_PORTS; port_num++) {
+ ret = gs_port_alloc(port_num, &coding);
+ if (ret == -EBUSY)
+ continue;
+ if (ret)
+ return ret;
+ break;
+ }
+ if (ret)
+ return ret;
+
+ /* ... and sysfs class devices, so mdev/udev make /dev/ttyGS* */
+
+ tty_dev = tty_port_register_device(&ports[port_num].port->port,
+ gs_tty_driver, port_num, NULL);
+ if (IS_ERR(tty_dev)) {
+ struct gs_port *port;
+ pr_err("%s: failed to register tty for port %d, err %ld\n",
+ __func__, port_num, PTR_ERR(tty_dev));
+
+ ret = PTR_ERR(tty_dev);
+ port = ports[port_num].port;
+ ports[port_num].port = NULL;
+ gserial_free_port(port);
+ goto err;
+ }
+ *line_num = port_num;
+ gserial_console_init();
+err:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(gserial_alloc_line);
+
+/**
+ * gserial_connect - notify TTY I/O glue that USB link is active
+ * @gser: the function, set up with endpoints and descriptors
+ * @port_num: which port is active
+ * Context: any (usually from irq)
+ *
+ * This is called activate endpoints and let the TTY layer know that
+ * the connection is active ... not unlike "carrier detect". It won't
+ * necessarily start I/O queues; unless the TTY is held open by any
+ * task, there would be no point. However, the endpoints will be
+ * activated so the USB host can perform I/O, subject to basic USB
+ * hardware flow control.
+ *
+ * Caller needs to have set up the endpoints and USB function in @dev
+ * before calling this, as well as the appropriate (speed-specific)
+ * endpoint descriptors, and also have allocate @port_num by calling
+ * @gserial_alloc_line().
+ *
+ * Returns negative errno or zero.
+ * On success, ep->driver_data will be overwritten.
+ */
+int gserial_connect(struct gserial *gser, u8 port_num)
+{
+ struct gs_port *port;
+ unsigned long flags;
+ int status;
+
+ if (port_num >= MAX_U_SERIAL_PORTS)
+ return -ENXIO;
+
+ port = ports[port_num].port;
+ if (!port) {
+ pr_err("serial line %d not allocated.\n", port_num);
+ return -EINVAL;
+ }
+ if (port->port_usb) {
+ pr_err("serial line %d is in use.\n", port_num);
+ return -EBUSY;
+ }
+
+ /* activate the endpoints */
+ status = usb_ep_enable(gser->in);
+ if (status < 0)
+ return status;
+ gser->in->driver_data = port;
+
+ status = usb_ep_enable(gser->out);
+ if (status < 0)
+ goto fail_out;
+ gser->out->driver_data = port;
+
+ /* then tell the tty glue that I/O can work */
+ spin_lock_irqsave(&port->port_lock, flags);
+ gser->ioport = port;
+ port->port_usb = gser;
+
+ /* REVISIT unclear how best to handle this state...
+ * we don't really couple it with the Linux TTY.
+ */
+ gser->port_line_coding = port->port_line_coding;
+
+ /* REVISIT if waiting on "carrier detect", signal. */
+
+ /* if it's already open, start I/O ... and notify the serial
+ * protocol about open/close status (connect/disconnect).
+ */
+ if (port->port.count) {
+ pr_debug("gserial_connect: start ttyGS%d\n", port->port_num);
+ gs_start_io(port);
+ if (gser->connect)
+ gser->connect(gser);
+ } else {
+ if (gser->disconnect)
+ gser->disconnect(gser);
+ }
+
+ status = gs_console_connect(port_num);
+ spin_unlock_irqrestore(&port->port_lock, flags);
+
+ return status;
+
+fail_out:
+ usb_ep_disable(gser->in);
+ return status;
+}
+EXPORT_SYMBOL_GPL(gserial_connect);
+/**
+ * gserial_disconnect - notify TTY I/O glue that USB link is inactive
+ * @gser: the function, on which gserial_connect() was called
+ * Context: any (usually from irq)
+ *
+ * This is called to deactivate endpoints and let the TTY layer know
+ * that the connection went inactive ... not unlike "hangup".
+ *
+ * On return, the state is as if gserial_connect() had never been called;
+ * there is no active USB I/O on these endpoints.
+ */
+void gserial_disconnect(struct gserial *gser)
+{
+ struct gs_port *port = gser->ioport;
+ unsigned long flags;
+
+ if (!port)
+ return;
+
+ /* tell the TTY glue not to do I/O here any more */
+ spin_lock_irqsave(&port->port_lock, flags);
+
+ /* REVISIT as above: how best to track this? */
+ port->port_line_coding = gser->port_line_coding;
+
+ port->port_usb = NULL;
+ gser->ioport = NULL;
+ if (port->port.count > 0 || port->openclose) {
+ wake_up_interruptible(&port->drain_wait);
+ if (port->port.tty)
+ tty_hangup(port->port.tty);
+ }
+ spin_unlock_irqrestore(&port->port_lock, flags);
+
+ /* disable endpoints, aborting down any active I/O */
+ usb_ep_disable(gser->out);
+ usb_ep_disable(gser->in);
+
+ /* finally, free any unused/unusable I/O buffers */
+ spin_lock_irqsave(&port->port_lock, flags);
+ if (port->port.count == 0 && !port->openclose)
+ gs_buf_free(&port->port_write_buf);
+ gs_free_requests(gser->out, &port->read_pool, NULL);
+ gs_free_requests(gser->out, &port->read_queue, NULL);
+ gs_free_requests(gser->in, &port->write_pool, NULL);
+
+ port->read_allocated = port->read_started =
+ port->write_allocated = port->write_started = 0;
+
+ gs_console_disconnect(gser->in);
+ spin_unlock_irqrestore(&port->port_lock, flags);
+}
+EXPORT_SYMBOL_GPL(gserial_disconnect);
+
+static int userial_init(void)
+{
+ unsigned i;
+ int status;
+
+ gs_tty_driver = alloc_tty_driver(MAX_U_SERIAL_PORTS);
+ if (!gs_tty_driver)
+ return -ENOMEM;
+
+ gs_tty_driver->driver_name = "g_serial";
+ gs_tty_driver->name = "ttyGS";
+ /* uses dynamically assigned dev_t values */
+
+ gs_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
+ gs_tty_driver->subtype = SERIAL_TYPE_NORMAL;
+ gs_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
+ gs_tty_driver->init_termios = tty_std_termios;
+
+ /* 9600-8-N-1 ... matches defaults expected by "usbser.sys" on
+ * MS-Windows. Otherwise, most of these flags shouldn't affect
+ * anything unless we were to actually hook up to a serial line.
+ */
+ gs_tty_driver->init_termios.c_cflag =
+ B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+ gs_tty_driver->init_termios.c_ispeed = 9600;
+ gs_tty_driver->init_termios.c_ospeed = 9600;
+
+ tty_set_operations(gs_tty_driver, &gs_tty_ops);
+ for (i = 0; i < MAX_U_SERIAL_PORTS; i++)
+ mutex_init(&ports[i].lock);
+
+ /* export the driver ... */
+ status = tty_register_driver(gs_tty_driver);
+ if (status) {
+ pr_err("%s: cannot register, err %d\n",
+ __func__, status);
+ goto fail;
+ }
+
+ pr_debug("%s: registered %d ttyGS* device%s\n", __func__,
+ MAX_U_SERIAL_PORTS,
+ (MAX_U_SERIAL_PORTS == 1) ? "" : "s");
+
+ return status;
+fail:
+ put_tty_driver(gs_tty_driver);
+ gs_tty_driver = NULL;
+ return status;
+}
+module_init(userial_init);
+
+static void userial_cleanup(void)
+{
+ tty_unregister_driver(gs_tty_driver);
+ put_tty_driver(gs_tty_driver);
+ gs_tty_driver = NULL;
+}
+module_exit(userial_cleanup);
+
+MODULE_LICENSE("GPL");
diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig
index 35cc641..304c9b4 100644
--- a/drivers/usb/gadget/Kconfig
+++ b/drivers/usb/gadget/Kconfig
@@ -152,9 +152,6 @@ config USB_F_ACM
config USB_F_SS_LB
tristate
-config USB_U_SERIAL
- tristate
-
config USB_U_ETHER
tristate
diff --git a/drivers/usb/gadget/function/Makefile b/drivers/usb/gadget/function/Makefile
index 86e8252..57f5ed0 100644
--- a/drivers/usb/gadget/function/Makefile
+++ b/drivers/usb/gadget/function/Makefile
@@ -10,7 +10,6 @@ usb_f_acm-y := f_acm.o
obj-$(CONFIG_USB_F_ACM) += usb_f_acm.o
usb_f_ss_lb-y := f_loopback.o f_sourcesink.o
obj-$(CONFIG_USB_F_SS_LB) += usb_f_ss_lb.o
-obj-$(CONFIG_USB_U_SERIAL) += u_serial.o
usb_f_serial-y := f_serial.o
obj-$(CONFIG_USB_F_SERIAL) += usb_f_serial.o
usb_f_obex-y := f_obex.o
diff --git a/drivers/usb/gadget/function/f_acm.c b/drivers/usb/gadget/function/f_acm.c
index 5e3828d..5d00da1 100644
--- a/drivers/usb/gadget/function/f_acm.c
+++ b/drivers/usb/gadget/function/f_acm.c
@@ -19,9 +19,7 @@
#include <linux/module.h>
#include <linux/device.h>
#include <linux/err.h>
-
-#include "u_serial.h"
-
+#include <linux/usb/u_serial.h>
/*
* This CDC ACM function support just wraps control functions and
diff --git a/drivers/usb/gadget/function/f_obex.c b/drivers/usb/gadget/function/f_obex.c
index d43e86c..6e7acd4 100644
--- a/drivers/usb/gadget/function/f_obex.c
+++ b/drivers/usb/gadget/function/f_obex.c
@@ -18,9 +18,7 @@
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
-
-#include "u_serial.h"
-
+#include <linux/usb/u_serial.h>
/*
* This CDC OBEX function support just packages a TTY-ish byte stream.
diff --git a/drivers/usb/gadget/function/f_serial.c b/drivers/usb/gadget/function/f_serial.c
index cb00ada..c589982 100644
--- a/drivers/usb/gadget/function/f_serial.c
+++ b/drivers/usb/gadget/function/f_serial.c
@@ -14,8 +14,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
-
-#include "u_serial.h"
+#include <linux/usb/u_serial.h>
/*
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c
deleted file mode 100644
index 9b0805f..0000000
--- a/drivers/usb/gadget/function/u_serial.c
+++ /dev/null
@@ -1,1606 +0,0 @@
-/*
- * u_serial.c - utilities for USB gadget "serial port"/TTY support
- *
- * Copyright (C) 2003 Al Borchers (alborchers@steinerpoint.com)
- * Copyright (C) 2008 David Brownell
- * Copyright (C) 2008 by Nokia Corporation
- *
- * This code also borrows from usbserial.c, which is
- * Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
- * Copyright (C) 2000 Peter Berger (pberger@brimson.com)
- * Copyright (C) 2000 Al Borchers (alborchers@steinerpoint.com)
- *
- * This software is distributed under the terms of the GNU General
- * Public License ("GPL") as published by the Free Software Foundation,
- * either version 2 of that License or (at your option) any later version.
- */
-
-/* #define VERBOSE_DEBUG */
-
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/interrupt.h>
-#include <linux/device.h>
-#include <linux/delay.h>
-#include <linux/tty.h>
-#include <linux/tty_flip.h>
-#include <linux/slab.h>
-#include <linux/export.h>
-#include <linux/module.h>
-#include <linux/console.h>
-#include <linux/kthread.h>
-
-#include "u_serial.h"
-
-
-/*
- * This component encapsulates the TTY layer glue needed to provide basic
- * "serial port" functionality through the USB gadget stack. Each such
- * port is exposed through a /dev/ttyGS* node.
- *
- * After this module has been loaded, the individual TTY port can be requested
- * (gserial_alloc_line()) and it will stay available until they are removed
- * (gserial_free_line()). Each one may be connected to a USB function
- * (gserial_connect), or disconnected (with gserial_disconnect) when the USB
- * host issues a config change event. Data can only flow when the port is
- * connected to the host.
- *
- * A given TTY port can be made available in multiple configurations.
- * For example, each one might expose a ttyGS0 node which provides a
- * login application. In one case that might use CDC ACM interface 0,
- * while another configuration might use interface 3 for that. The
- * work to handle that (including descriptor management) is not part
- * of this component.
- *
- * Configurations may expose more than one TTY port. For example, if
- * ttyGS0 provides login service, then ttyGS1 might provide dialer access
- * for a telephone or fax link. And ttyGS2 might be something that just
- * needs a simple byte stream interface for some messaging protocol that
- * is managed in userspace ... OBEX, PTP, and MTP have been mentioned.
- *
- *
- * gserial is the lifecycle interface, used by USB functions
- * gs_port is the I/O nexus, used by the tty driver
- * tty_struct links to the tty/filesystem framework
- *
- * gserial <---> gs_port ... links will be null when the USB link is
- * inactive; managed by gserial_{connect,disconnect}(). each gserial
- * instance can wrap its own USB control protocol.
- * gserial->ioport == usb_ep->driver_data ... gs_port
- * gs_port->port_usb ... gserial
- *
- * gs_port <---> tty_struct ... links will be null when the TTY file
- * isn't opened; managed by gs_open()/gs_close()
- * gserial->port_tty ... tty_struct
- * tty_struct->driver_data ... gserial
- */
-
-/* RX and TX queues can buffer QUEUE_SIZE packets before they hit the
- * next layer of buffering. For TX that's a circular buffer; for RX
- * consider it a NOP. A third layer is provided by the TTY code.
- */
-#define QUEUE_SIZE 16
-#define WRITE_BUF_SIZE 8192 /* TX only */
-#define GS_CONSOLE_BUF_SIZE 8192
-
-/* circular buffer */
-struct gs_buf {
- unsigned buf_size;
- char *buf_buf;
- char *buf_get;
- char *buf_put;
-};
-
-/* console info */
-struct gscons_info {
- struct gs_port *port;
- struct task_struct *console_thread;
- struct gs_buf con_buf;
- /* protect the buf and busy flag */
- spinlock_t con_lock;
- int req_busy;
- struct usb_request *console_req;
-};
-
-/*
- * The port structure holds info for each port, one for each minor number
- * (and thus for each /dev/ node).
- */
-struct gs_port {
- struct tty_port port;
- spinlock_t port_lock; /* guard port_* access */
-
- struct gserial *port_usb;
-
- bool openclose; /* open/close in progress */
- u8 port_num;
-
- struct list_head read_pool;
- int read_started;
- int read_allocated;
- struct list_head read_queue;
- unsigned n_read;
- struct tasklet_struct push;
-
- struct list_head write_pool;
- int write_started;
- int write_allocated;
- struct gs_buf port_write_buf;
- wait_queue_head_t drain_wait; /* wait while writes drain */
- bool write_busy;
- wait_queue_head_t close_wait;
-
- /* REVISIT this state ... */
- struct usb_cdc_line_coding port_line_coding; /* 8-N-1 etc */
-};
-
-static struct portmaster {
- struct mutex lock; /* protect open/close */
- struct gs_port *port;
-} ports[MAX_U_SERIAL_PORTS];
-
-#define GS_CLOSE_TIMEOUT 15 /* seconds */
-
-
-
-#ifdef VERBOSE_DEBUG
-#ifndef pr_vdebug
-#define pr_vdebug(fmt, arg...) \
- pr_debug(fmt, ##arg)
-#endif /* pr_vdebug */
-#else
-#ifndef pr_vdebug
-#define pr_vdebug(fmt, arg...) \
- ({ if (0) pr_debug(fmt, ##arg); })
-#endif /* pr_vdebug */
-#endif
-
-/*-------------------------------------------------------------------------*/
-
-/* Circular Buffer */
-
-/*
- * gs_buf_alloc
- *
- * Allocate a circular buffer and all associated memory.
- */
-static int gs_buf_alloc(struct gs_buf *gb, unsigned size)
-{
- gb->buf_buf = kmalloc(size, GFP_KERNEL);
- if (gb->buf_buf == NULL)
- return -ENOMEM;
-
- gb->buf_size = size;
- gb->buf_put = gb->buf_buf;
- gb->buf_get = gb->buf_buf;
-
- return 0;
-}
-
-/*
- * gs_buf_free
- *
- * Free the buffer and all associated memory.
- */
-static void gs_buf_free(struct gs_buf *gb)
-{
- kfree(gb->buf_buf);
- gb->buf_buf = NULL;
-}
-
-/*
- * gs_buf_clear
- *
- * Clear out all data in the circular buffer.
- */
-static void gs_buf_clear(struct gs_buf *gb)
-{
- gb->buf_get = gb->buf_put;
- /* equivalent to a get of all data available */
-}
-
-/*
- * gs_buf_data_avail
- *
- * Return the number of bytes of data written into the circular
- * buffer.
- */
-static unsigned gs_buf_data_avail(struct gs_buf *gb)
-{
- return (gb->buf_size + gb->buf_put - gb->buf_get) % gb->buf_size;
-}
-
-/*
- * gs_buf_space_avail
- *
- * Return the number of bytes of space available in the circular
- * buffer.
- */
-static unsigned gs_buf_space_avail(struct gs_buf *gb)
-{
- return (gb->buf_size + gb->buf_get - gb->buf_put - 1) % gb->buf_size;
-}
-
-/*
- * gs_buf_put
- *
- * Copy data data from a user buffer and put it into the circular buffer.
- * Restrict to the amount of space available.
- *
- * Return the number of bytes copied.
- */
-static unsigned
-gs_buf_put(struct gs_buf *gb, const char *buf, unsigned count)
-{
- unsigned len;
-
- len = gs_buf_space_avail(gb);
- if (count > len)
- count = len;
-
- if (count == 0)
- return 0;
-
- len = gb->buf_buf + gb->buf_size - gb->buf_put;
- if (count > len) {
- memcpy(gb->buf_put, buf, len);
- memcpy(gb->buf_buf, buf+len, count - len);
- gb->buf_put = gb->buf_buf + count - len;
- } else {
- memcpy(gb->buf_put, buf, count);
- if (count < len)
- gb->buf_put += count;
- else /* count == len */
- gb->buf_put = gb->buf_buf;
- }
-
- return count;
-}
-
-/*
- * gs_buf_get
- *
- * Get data from the circular buffer and copy to the given buffer.
- * Restrict to the amount of data available.
- *
- * Return the number of bytes copied.
- */
-static unsigned
-gs_buf_get(struct gs_buf *gb, char *buf, unsigned count)
-{
- unsigned len;
-
- len = gs_buf_data_avail(gb);
- if (count > len)
- count = len;
-
- if (count == 0)
- return 0;
-
- len = gb->buf_buf + gb->buf_size - gb->buf_get;
- if (count > len) {
- memcpy(buf, gb->buf_get, len);
- memcpy(buf+len, gb->buf_buf, count - len);
- gb->buf_get = gb->buf_buf + count - len;
- } else {
- memcpy(buf, gb->buf_get, count);
- if (count < len)
- gb->buf_get += count;
- else /* count == len */
- gb->buf_get = gb->buf_buf;
- }
-
- return count;
-}
-
-/*-------------------------------------------------------------------------*/
-
-/* I/O glue between TTY (upper) and USB function (lower) driver layers */
-
-/*
- * gs_alloc_req
- *
- * Allocate a usb_request and its buffer. Returns a pointer to the
- * usb_request or NULL if there is an error.
- */
-struct usb_request *
-gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t kmalloc_flags)
-{
- struct usb_request *req;
-
- req = usb_ep_alloc_request(ep, kmalloc_flags);
-
- if (req != NULL) {
- req->length = len;
- req->buf = kmalloc(len, kmalloc_flags);
- if (req->buf == NULL) {
- usb_ep_free_request(ep, req);
- return NULL;
- }
- }
-
- return req;
-}
-EXPORT_SYMBOL_GPL(gs_alloc_req);
-
-/*
- * gs_free_req
- *
- * Free a usb_request and its buffer.
- */
-void gs_free_req(struct usb_ep *ep, struct usb_request *req)
-{
- kfree(req->buf);
- usb_ep_free_request(ep, req);
-}
-EXPORT_SYMBOL_GPL(gs_free_req);
-
-/*
- * gs_send_packet
- *
- * If there is data to send, a packet is built in the given
- * buffer and the size is returned. If there is no data to
- * send, 0 is returned.
- *
- * Called with port_lock held.
- */
-static unsigned
-gs_send_packet(struct gs_port *port, char *packet, unsigned size)
-{
- unsigned len;
-
- len = gs_buf_data_avail(&port->port_write_buf);
- if (len < size)
- size = len;
- if (size != 0)
- size = gs_buf_get(&port->port_write_buf, packet, size);
- return size;
-}
-
-/*
- * gs_start_tx
- *
- * This function finds available write requests, calls
- * gs_send_packet to fill these packets with data, and
- * continues until either there are no more write requests
- * available or no more data to send. This function is
- * run whenever data arrives or write requests are available.
- *
- * Context: caller owns port_lock; port_usb is non-null.
- */
-static int gs_start_tx(struct gs_port *port)
-/*
-__releases(&port->port_lock)
-__acquires(&port->port_lock)
-*/
-{
- struct list_head *pool = &port->write_pool;
- struct usb_ep *in;
- int status = 0;
- bool do_tty_wake = false;
-
- if (!port->port_usb)
- return status;
-
- in = port->port_usb->in;
-
- while (!port->write_busy && !list_empty(pool)) {
- struct usb_request *req;
- int len;
-
- if (port->write_started >= QUEUE_SIZE)
- break;
-
- req = list_entry(pool->next, struct usb_request, list);
- len = gs_send_packet(port, req->buf, in->maxpacket);
- if (len == 0) {
- wake_up_interruptible(&port->drain_wait);
- break;
- }
- do_tty_wake = true;
-
- req->length = len;
- list_del(&req->list);
- req->zero = (gs_buf_data_avail(&port->port_write_buf) == 0);
-
- pr_vdebug("ttyGS%d: tx len=%d, 0x%02x 0x%02x 0x%02x ...\n",
- port->port_num, len, *((u8 *)req->buf),
- *((u8 *)req->buf+1), *((u8 *)req->buf+2));
-
- /* Drop lock while we call out of driver; completions
- * could be issued while we do so. Disconnection may
- * happen too; maybe immediately before we queue this!
- *
- * NOTE that we may keep sending data for a while after
- * the TTY closed (dev->ioport->port_tty is NULL).
- */
- port->write_busy = true;
- spin_unlock(&port->port_lock);
- status = usb_ep_queue(in, req, GFP_ATOMIC);
- spin_lock(&port->port_lock);
- port->write_busy = false;
-
- if (status) {
- pr_debug("%s: %s %s err %d\n",
- __func__, "queue", in->name, status);
- list_add(&req->list, pool);
- break;
- }
-
- port->write_started++;
-
- /* abort immediately after disconnect */
- if (!port->port_usb)
- break;
- }
-
- if (do_tty_wake && port->port.tty)
- tty_wakeup(port->port.tty);
- return status;
-}
-
-/*
- * Context: caller owns port_lock, and port_usb is set
- */
-static unsigned gs_start_rx(struct gs_port *port)
-/*
-__releases(&port->port_lock)
-__acquires(&port->port_lock)
-*/
-{
- struct list_head *pool = &port->read_pool;
- struct usb_ep *out = port->port_usb->out;
-
- while (!list_empty(pool)) {
- struct usb_request *req;
- int status;
- struct tty_struct *tty;
-
- /* no more rx if closed */
- tty = port->port.tty;
- if (!tty)
- break;
-
- if (port->read_started >= QUEUE_SIZE)
- break;
-
- req = list_entry(pool->next, struct usb_request, list);
- list_del(&req->list);
- req->length = out->maxpacket;
-
- /* drop lock while we call out; the controller driver
- * may need to call us back (e.g. for disconnect)
- */
- spin_unlock(&port->port_lock);
- status = usb_ep_queue(out, req, GFP_ATOMIC);
- spin_lock(&port->port_lock);
-
- if (status) {
- pr_debug("%s: %s %s err %d\n",
- __func__, "queue", out->name, status);
- list_add(&req->list, pool);
- break;
- }
- port->read_started++;
-
- /* abort immediately after disconnect */
- if (!port->port_usb)
- break;
- }
- return port->read_started;
-}
-
-/*
- * RX tasklet takes data out of the RX queue and hands it up to the TTY
- * layer until it refuses to take any more data (or is throttled back).
- * Then it issues reads for any further data.
- *
- * If the RX queue becomes full enough that no usb_request is queued,
- * the OUT endpoint may begin NAKing as soon as its FIFO fills up.
- * So QUEUE_SIZE packets plus however many the FIFO holds (usually two)
- * can be buffered before the TTY layer's buffers (currently 64 KB).
- */
-static void gs_rx_push(unsigned long _port)
-{
- struct gs_port *port = (void *)_port;
- struct tty_struct *tty;
- struct list_head *queue = &port->read_queue;
- bool disconnect = false;
- bool do_push = false;
-
- /* hand any queued data to the tty */
- spin_lock_irq(&port->port_lock);
- tty = port->port.tty;
- while (!list_empty(queue)) {
- struct usb_request *req;
-
- req = list_first_entry(queue, struct usb_request, list);
-
- /* leave data queued if tty was rx throttled */
- if (tty && tty_throttled(tty))
- break;
-
- switch (req->status) {
- case -ESHUTDOWN:
- disconnect = true;
- pr_vdebug("ttyGS%d: shutdown\n", port->port_num);
- break;
-
- default:
- /* presumably a transient fault */
- pr_warn("ttyGS%d: unexpected RX status %d\n",
- port->port_num, req->status);
- /* FALLTHROUGH */
- case 0:
- /* normal completion */
- break;
- }
-
- /* push data to (open) tty */
- if (req->actual) {
- char *packet = req->buf;
- unsigned size = req->actual;
- unsigned n;
- int count;
-
- /* we may have pushed part of this packet already... */
- n = port->n_read;
- if (n) {
- packet += n;
- size -= n;
- }
-
- count = tty_insert_flip_string(&port->port, packet,
- size);
- if (count)
- do_push = true;
- if (count != size) {
- /* stop pushing; TTY layer can't handle more */
- port->n_read += count;
- pr_vdebug("ttyGS%d: rx block %d/%d\n",
- port->port_num, count, req->actual);
- break;
- }
- port->n_read = 0;
- }
-
- list_move(&req->list, &port->read_pool);
- port->read_started--;
- }
-
- /* Push from tty to ldisc; this is handled by a workqueue,
- * so we won't get callbacks and can hold port_lock
- */
- if (do_push)
- tty_flip_buffer_push(&port->port);
-
-
- /* We want our data queue to become empty ASAP, keeping data
- * in the tty and ldisc (not here). If we couldn't push any
- * this time around, there may be trouble unless there's an
- * implicit tty_unthrottle() call on its way...
- *
- * REVISIT we should probably add a timer to keep the tasklet
- * from starving ... but it's not clear that case ever happens.
- */
- if (!list_empty(queue) && tty) {
- if (!tty_throttled(tty)) {
- if (do_push)
- tasklet_schedule(&port->push);
- else
- pr_warn("ttyGS%d: RX not scheduled?\n",
- port->port_num);
- }
- }
-
- /* If we're still connected, refill the USB RX queue. */
- if (!disconnect && port->port_usb)
- gs_start_rx(port);
-
- spin_unlock_irq(&port->port_lock);
-}
-
-static void gs_read_complete(struct usb_ep *ep, struct usb_request *req)
-{
- struct gs_port *port = ep->driver_data;
-
- /* Queue all received data until the tty layer is ready for it. */
- spin_lock(&port->port_lock);
- list_add_tail(&req->list, &port->read_queue);
- tasklet_schedule(&port->push);
- spin_unlock(&port->port_lock);
-}
-
-static void gs_write_complete(struct usb_ep *ep, struct usb_request *req)
-{
- struct gs_port *port = ep->driver_data;
-
- spin_lock(&port->port_lock);
- list_add(&req->list, &port->write_pool);
- port->write_started--;
-
- switch (req->status) {
- default:
- /* presumably a transient fault */
- pr_warn("%s: unexpected %s status %d\n",
- __func__, ep->name, req->status);
- /* FALL THROUGH */
- case 0:
- /* normal completion */
- gs_start_tx(port);
- break;
-
- case -ESHUTDOWN:
- /* disconnect */
- pr_vdebug("%s: %s shutdown\n", __func__, ep->name);
- break;
- }
-
- spin_unlock(&port->port_lock);
-}
-
-static void gs_free_requests(struct usb_ep *ep, struct list_head *head,
- int *allocated)
-{
- struct usb_request *req;
-
- while (!list_empty(head)) {
- req = list_entry(head->next, struct usb_request, list);
- list_del(&req->list);
- gs_free_req(ep, req);
- if (allocated)
- (*allocated)--;
- }
-}
-
-static int gs_alloc_requests(struct usb_ep *ep, struct list_head *head,
- void (*fn)(struct usb_ep *, struct usb_request *),
- int *allocated)
-{
- int i;
- struct usb_request *req;
- int n = allocated ? QUEUE_SIZE - *allocated : QUEUE_SIZE;
-
- /* Pre-allocate up to QUEUE_SIZE transfers, but if we can't
- * do quite that many this time, don't fail ... we just won't
- * be as speedy as we might otherwise be.
- */
- for (i = 0; i < n; i++) {
- req = gs_alloc_req(ep, ep->maxpacket, GFP_ATOMIC);
- if (!req)
- return list_empty(head) ? -ENOMEM : 0;
- req->complete = fn;
- list_add_tail(&req->list, head);
- if (allocated)
- (*allocated)++;
- }
- return 0;
-}
-
-/**
- * gs_start_io - start USB I/O streams
- * @dev: encapsulates endpoints to use
- * Context: holding port_lock; port_tty and port_usb are non-null
- *
- * We only start I/O when something is connected to both sides of
- * this port. If nothing is listening on the host side, we may
- * be pointlessly filling up our TX buffers and FIFO.
- */
-static int gs_start_io(struct gs_port *port)
-{
- struct list_head *head = &port->read_pool;
- struct usb_ep *ep = port->port_usb->out;
- int status;
- unsigned started;
-
- /* Allocate RX and TX I/O buffers. We can't easily do this much
- * earlier (with GFP_KERNEL) because the requests are coupled to
- * endpoints, as are the packet sizes we'll be using. Different
- * configurations may use different endpoints with a given port;
- * and high speed vs full speed changes packet sizes too.
- */
- status = gs_alloc_requests(ep, head, gs_read_complete,
- &port->read_allocated);
- if (status)
- return status;
-
- status = gs_alloc_requests(port->port_usb->in, &port->write_pool,
- gs_write_complete, &port->write_allocated);
- if (status) {
- gs_free_requests(ep, head, &port->read_allocated);
- return status;
- }
-
- /* queue read requests */
- port->n_read = 0;
- started = gs_start_rx(port);
-
- /* unblock any pending writes into our circular buffer */
- if (started) {
- tty_wakeup(port->port.tty);
- } else {
- gs_free_requests(ep, head, &port->read_allocated);
- gs_free_requests(port->port_usb->in, &port->write_pool,
- &port->write_allocated);
- status = -EIO;
- }
-
- return status;
-}
-
-/*-------------------------------------------------------------------------*/
-
-/* TTY Driver */
-
-/*
- * gs_open sets up the link between a gs_port and its associated TTY.
- * That link is broken *only* by TTY close(), and all driver methods
- * know that.
- */
-static int gs_open(struct tty_struct *tty, struct file *file)
-{
- int port_num = tty->index;
- struct gs_port *port;
- int status;
-
- do {
- mutex_lock(&ports[port_num].lock);
- port = ports[port_num].port;
- if (!port)
- status = -ENODEV;
- else {
- spin_lock_irq(&port->port_lock);
-
- /* already open? Great. */
- if (port->port.count) {
- status = 0;
- port->port.count++;
-
- /* currently opening/closing? wait ... */
- } else if (port->openclose) {
- status = -EBUSY;
-
- /* ... else we do the work */
- } else {
- status = -EAGAIN;
- port->openclose = true;
- }
- spin_unlock_irq(&port->port_lock);
- }
- mutex_unlock(&ports[port_num].lock);
-
- switch (status) {
- default:
- /* fully handled */
- return status;
- case -EAGAIN:
- /* must do the work */
- break;
- case -EBUSY:
- /* wait for EAGAIN task to finish */
- msleep(1);
- /* REVISIT could have a waitchannel here, if
- * concurrent open performance is important
- */
- break;
- }
- } while (status != -EAGAIN);
-
- /* Do the "real open" */
- spin_lock_irq(&port->port_lock);
-
- /* allocate circular buffer on first open */
- if (port->port_write_buf.buf_buf == NULL) {
-
- spin_unlock_irq(&port->port_lock);
- status = gs_buf_alloc(&port->port_write_buf, WRITE_BUF_SIZE);
- spin_lock_irq(&port->port_lock);
-
- if (status) {
- pr_debug("gs_open: ttyGS%d (%p,%p) no buffer\n",
- port->port_num, tty, file);
- port->openclose = false;
- goto exit_unlock_port;
- }
- }
-
- /* REVISIT if REMOVED (ports[].port NULL), abort the open
- * to let rmmod work faster (but this way isn't wrong).
- */
-
- /* REVISIT maybe wait for "carrier detect" */
-
- tty->driver_data = port;
- port->port.tty = tty;
-
- port->port.count = 1;
- port->openclose = false;
-
- /* if connected, start the I/O stream */
- if (port->port_usb) {
- struct gserial *gser = port->port_usb;
-
- pr_debug("gs_open: start ttyGS%d\n", port->port_num);
- gs_start_io(port);
-
- if (gser->connect)
- gser->connect(gser);
- }
-
- pr_debug("gs_open: ttyGS%d (%p,%p)\n", port->port_num, tty, file);
-
- status = 0;
-
-exit_unlock_port:
- spin_unlock_irq(&port->port_lock);
- return status;
-}
-
-static int gs_writes_finished(struct gs_port *p)
-{
- int cond;
-
- /* return true on disconnect or empty buffer */
- spin_lock_irq(&p->port_lock);
- cond = (p->port_usb == NULL) || !gs_buf_data_avail(&p->port_write_buf);
- spin_unlock_irq(&p->port_lock);
-
- return cond;
-}
-
-static void gs_close(struct tty_struct *tty, struct file *file)
-{
- struct gs_port *port = tty->driver_data;
- struct gserial *gser;
-
- spin_lock_irq(&port->port_lock);
-
- if (port->port.count != 1) {
- if (port->port.count == 0)
- WARN_ON(1);
- else
- --port->port.count;
- goto exit;
- }
-
- pr_debug("gs_close: ttyGS%d (%p,%p) ...\n", port->port_num, tty, file);
-
- /* mark port as closing but in use; we can drop port lock
- * and sleep if necessary
- */
- port->openclose = true;
- port->port.count = 0;
-
- gser = port->port_usb;
- if (gser && gser->disconnect)
- gser->disconnect(gser);
-
- /* wait for circular write buffer to drain, disconnect, or at
- * most GS_CLOSE_TIMEOUT seconds; then discard the rest
- */
- if (gs_buf_data_avail(&port->port_write_buf) > 0 && gser) {
- spin_unlock_irq(&port->port_lock);
- wait_event_interruptible_timeout(port->drain_wait,
- gs_writes_finished(port),
- GS_CLOSE_TIMEOUT * HZ);
- spin_lock_irq(&port->port_lock);
- gser = port->port_usb;
- }
-
- /* Iff we're disconnected, there can be no I/O in flight so it's
- * ok to free the circular buffer; else just scrub it. And don't
- * let the push tasklet fire again until we're re-opened.
- */
- if (gser == NULL)
- gs_buf_free(&port->port_write_buf);
- else
- gs_buf_clear(&port->port_write_buf);
-
- port->port.tty = NULL;
-
- port->openclose = false;
-
- pr_debug("gs_close: ttyGS%d (%p,%p) done!\n",
- port->port_num, tty, file);
-
- wake_up(&port->close_wait);
-exit:
- spin_unlock_irq(&port->port_lock);
-}
-
-static int gs_write(struct tty_struct *tty, const unsigned char *buf, int count)
-{
- struct gs_port *port = tty->driver_data;
- unsigned long flags;
-
- pr_vdebug("gs_write: ttyGS%d (%p) writing %d bytes\n",
- port->port_num, tty, count);
-
- spin_lock_irqsave(&port->port_lock, flags);
- if (count)
- count = gs_buf_put(&port->port_write_buf, buf, count);
- /* treat count == 0 as flush_chars() */
- if (port->port_usb)
- gs_start_tx(port);
- spin_unlock_irqrestore(&port->port_lock, flags);
-
- return count;
-}
-
-static int gs_put_char(struct tty_struct *tty, unsigned char ch)
-{
- struct gs_port *port = tty->driver_data;
- unsigned long flags;
- int status;
-
- pr_vdebug("gs_put_char: (%d,%p) char=0x%x, called from %ps\n",
- port->port_num, tty, ch, __builtin_return_address(0));
-
- spin_lock_irqsave(&port->port_lock, flags);
- status = gs_buf_put(&port->port_write_buf, &ch, 1);
- spin_unlock_irqrestore(&port->port_lock, flags);
-
- return status;
-}
-
-static void gs_flush_chars(struct tty_struct *tty)
-{
- struct gs_port *port = tty->driver_data;
- unsigned long flags;
-
- pr_vdebug("gs_flush_chars: (%d,%p)\n", port->port_num, tty);
-
- spin_lock_irqsave(&port->port_lock, flags);
- if (port->port_usb)
- gs_start_tx(port);
- spin_unlock_irqrestore(&port->port_lock, flags);
-}
-
-static int gs_write_room(struct tty_struct *tty)
-{
- struct gs_port *port = tty->driver_data;
- unsigned long flags;
- int room = 0;
-
- spin_lock_irqsave(&port->port_lock, flags);
- if (port->port_usb)
- room = gs_buf_space_avail(&port->port_write_buf);
- spin_unlock_irqrestore(&port->port_lock, flags);
-
- pr_vdebug("gs_write_room: (%d,%p) room=%d\n",
- port->port_num, tty, room);
-
- return room;
-}
-
-static int gs_chars_in_buffer(struct tty_struct *tty)
-{
- struct gs_port *port = tty->driver_data;
- unsigned long flags;
- int chars = 0;
-
- spin_lock_irqsave(&port->port_lock, flags);
- chars = gs_buf_data_avail(&port->port_write_buf);
- spin_unlock_irqrestore(&port->port_lock, flags);
-
- pr_vdebug("gs_chars_in_buffer: (%d,%p) chars=%d\n",
- port->port_num, tty, chars);
-
- return chars;
-}
-
-/* undo side effects of setting TTY_THROTTLED */
-static void gs_unthrottle(struct tty_struct *tty)
-{
- struct gs_port *port = tty->driver_data;
- unsigned long flags;
-
- spin_lock_irqsave(&port->port_lock, flags);
- if (port->port_usb) {
- /* Kickstart read queue processing. We don't do xon/xoff,
- * rts/cts, or other handshaking with the host, but if the
- * read queue backs up enough we'll be NAKing OUT packets.
- */
- tasklet_schedule(&port->push);
- pr_vdebug("ttyGS%d: unthrottle\n", port->port_num);
- }
- spin_unlock_irqrestore(&port->port_lock, flags);
-}
-
-static int gs_break_ctl(struct tty_struct *tty, int duration)
-{
- struct gs_port *port = tty->driver_data;
- int status = 0;
- struct gserial *gser;
-
- pr_vdebug("gs_break_ctl: ttyGS%d, send break (%d) \n",
- port->port_num, duration);
-
- spin_lock_irq(&port->port_lock);
- gser = port->port_usb;
- if (gser && gser->send_break)
- status = gser->send_break(gser, duration);
- spin_unlock_irq(&port->port_lock);
-
- return status;
-}
-
-static const struct tty_operations gs_tty_ops = {
- .open = gs_open,
- .close = gs_close,
- .write = gs_write,
- .put_char = gs_put_char,
- .flush_chars = gs_flush_chars,
- .write_room = gs_write_room,
- .chars_in_buffer = gs_chars_in_buffer,
- .unthrottle = gs_unthrottle,
- .break_ctl = gs_break_ctl,
-};
-
-/*-------------------------------------------------------------------------*/
-
-static struct tty_driver *gs_tty_driver;
-
-#ifdef CONFIG_U_SERIAL_CONSOLE
-
-static struct gscons_info gscons_info;
-static struct console gserial_cons;
-
-static struct usb_request *gs_request_new(struct usb_ep *ep)
-{
- struct usb_request *req = usb_ep_alloc_request(ep, GFP_ATOMIC);
- if (!req)
- return NULL;
-
- req->buf = kmalloc(ep->maxpacket, GFP_ATOMIC);
- if (!req->buf) {
- usb_ep_free_request(ep, req);
- return NULL;
- }
-
- return req;
-}
-
-static void gs_request_free(struct usb_request *req, struct usb_ep *ep)
-{
- if (!req)
- return;
-
- kfree(req->buf);
- usb_ep_free_request(ep, req);
-}
-
-static void gs_complete_out(struct usb_ep *ep, struct usb_request *req)
-{
- struct gscons_info *info = &gscons_info;
-
- switch (req->status) {
- default:
- pr_warn("%s: unexpected %s status %d\n",
- __func__, ep->name, req->status);
- case 0:
- /* normal completion */
- spin_lock(&info->con_lock);
- info->req_busy = 0;
- spin_unlock(&info->con_lock);
-
- wake_up_process(info->console_thread);
- break;
- case -ESHUTDOWN:
- /* disconnect */
- pr_vdebug("%s: %s shutdown\n", __func__, ep->name);
- break;
- }
-}
-
-static int gs_console_connect(int port_num)
-{
- struct gscons_info *info = &gscons_info;
- struct gs_port *port;
- struct usb_ep *ep;
-
- if (port_num != gserial_cons.index) {
- pr_err("%s: port num [%d] is not support console\n",
- __func__, port_num);
- return -ENXIO;
- }
-
- port = ports[port_num].port;
- ep = port->port_usb->in;
- if (!info->console_req) {
- info->console_req = gs_request_new(ep);
- if (!info->console_req)
- return -ENOMEM;
- info->console_req->complete = gs_complete_out;
- }
-
- info->port = port;
- spin_lock(&info->con_lock);
- info->req_busy = 0;
- spin_unlock(&info->con_lock);
- pr_vdebug("port[%d] console connect!\n", port_num);
- return 0;
-}
-
-static void gs_console_disconnect(struct usb_ep *ep)
-{
- struct gscons_info *info = &gscons_info;
- struct usb_request *req = info->console_req;
-
- gs_request_free(req, ep);
- info->console_req = NULL;
-}
-
-static int gs_console_thread(void *data)
-{
- struct gscons_info *info = &gscons_info;
- struct gs_port *port;
- struct usb_request *req;
- struct usb_ep *ep;
- int xfer, ret, count, size;
-
- do {
- port = info->port;
- set_current_state(TASK_INTERRUPTIBLE);
- if (!port || !port->port_usb
- || !port->port_usb->in || !info->console_req)
- goto sched;
-
- req = info->console_req;
- ep = port->port_usb->in;
-
- spin_lock_irq(&info->con_lock);
- count = gs_buf_data_avail(&info->con_buf);
- size = ep->maxpacket;
-
- if (count > 0 && !info->req_busy) {
- set_current_state(TASK_RUNNING);
- if (count < size)
- size = count;
-
- xfer = gs_buf_get(&info->con_buf, req->buf, size);
- req->length = xfer;
-
- spin_unlock(&info->con_lock);
- ret = usb_ep_queue(ep, req, GFP_ATOMIC);
- spin_lock(&info->con_lock);
- if (ret < 0)
- info->req_busy = 0;
- else
- info->req_busy = 1;
-
- spin_unlock_irq(&info->con_lock);
- } else {
- spin_unlock_irq(&info->con_lock);
-sched:
- if (kthread_should_stop()) {
- set_current_state(TASK_RUNNING);
- break;
- }
- schedule();
- }
- } while (1);
-
- return 0;
-}
-
-static int gs_console_setup(struct console *co, char *options)
-{
- struct gscons_info *info = &gscons_info;
- int status;
-
- info->port = NULL;
- info->console_req = NULL;
- info->req_busy = 0;
- spin_lock_init(&info->con_lock);
-
- status = gs_buf_alloc(&info->con_buf, GS_CONSOLE_BUF_SIZE);
- if (status) {
- pr_err("%s: allocate console buffer failed\n", __func__);
- return status;
- }
-
- info->console_thread = kthread_create(gs_console_thread,
- co, "gs_console");
- if (IS_ERR(info->console_thread)) {
- pr_err("%s: cannot create console thread\n", __func__);
- gs_buf_free(&info->con_buf);
- return PTR_ERR(info->console_thread);
- }
- wake_up_process(info->console_thread);
-
- return 0;
-}
-
-static void gs_console_write(struct console *co,
- const char *buf, unsigned count)
-{
- struct gscons_info *info = &gscons_info;
- unsigned long flags;
-
- spin_lock_irqsave(&info->con_lock, flags);
- gs_buf_put(&info->con_buf, buf, count);
- spin_unlock_irqrestore(&info->con_lock, flags);
-
- wake_up_process(info->console_thread);
-}
-
-static struct tty_driver *gs_console_device(struct console *co, int *index)
-{
- struct tty_driver **p = (struct tty_driver **)co->data;
-
- if (!*p)
- return NULL;
-
- *index = co->index;
- return *p;
-}
-
-static struct console gserial_cons = {
- .name = "ttyGS",
- .write = gs_console_write,
- .device = gs_console_device,
- .setup = gs_console_setup,
- .flags = CON_PRINTBUFFER,
- .index = -1,
- .data = &gs_tty_driver,
-};
-
-static void gserial_console_init(void)
-{
- register_console(&gserial_cons);
-}
-
-static void gserial_console_exit(void)
-{
- struct gscons_info *info = &gscons_info;
-
- unregister_console(&gserial_cons);
- if (!IS_ERR_OR_NULL(info->console_thread))
- kthread_stop(info->console_thread);
- gs_buf_free(&info->con_buf);
-}
-
-#else
-
-static int gs_console_connect(int port_num)
-{
- return 0;
-}
-
-static void gs_console_disconnect(struct usb_ep *ep)
-{
-}
-
-static void gserial_console_init(void)
-{
-}
-
-static void gserial_console_exit(void)
-{
-}
-
-#endif
-
-static int
-gs_port_alloc(unsigned port_num, struct usb_cdc_line_coding *coding)
-{
- struct gs_port *port;
- int ret = 0;
-
- mutex_lock(&ports[port_num].lock);
- if (ports[port_num].port) {
- ret = -EBUSY;
- goto out;
- }
-
- port = kzalloc(sizeof(struct gs_port), GFP_KERNEL);
- if (port == NULL) {
- ret = -ENOMEM;
- goto out;
- }
-
- tty_port_init(&port->port);
- spin_lock_init(&port->port_lock);
- init_waitqueue_head(&port->drain_wait);
- init_waitqueue_head(&port->close_wait);
-
- tasklet_init(&port->push, gs_rx_push, (unsigned long) port);
-
- INIT_LIST_HEAD(&port->read_pool);
- INIT_LIST_HEAD(&port->read_queue);
- INIT_LIST_HEAD(&port->write_pool);
-
- port->port_num = port_num;
- port->port_line_coding = *coding;
-
- ports[port_num].port = port;
-out:
- mutex_unlock(&ports[port_num].lock);
- return ret;
-}
-
-static int gs_closed(struct gs_port *port)
-{
- int cond;
-
- spin_lock_irq(&port->port_lock);
- cond = (port->port.count == 0) && !port->openclose;
- spin_unlock_irq(&port->port_lock);
- return cond;
-}
-
-static void gserial_free_port(struct gs_port *port)
-{
- tasklet_kill(&port->push);
- /* wait for old opens to finish */
- wait_event(port->close_wait, gs_closed(port));
- WARN_ON(port->port_usb != NULL);
- tty_port_destroy(&port->port);
- kfree(port);
-}
-
-void gserial_free_line(unsigned char port_num)
-{
- struct gs_port *port;
-
- mutex_lock(&ports[port_num].lock);
- if (WARN_ON(!ports[port_num].port)) {
- mutex_unlock(&ports[port_num].lock);
- return;
- }
- port = ports[port_num].port;
- ports[port_num].port = NULL;
- mutex_unlock(&ports[port_num].lock);
-
- gserial_free_port(port);
- tty_unregister_device(gs_tty_driver, port_num);
- gserial_console_exit();
-}
-EXPORT_SYMBOL_GPL(gserial_free_line);
-
-int gserial_alloc_line(unsigned char *line_num)
-{
- struct usb_cdc_line_coding coding;
- struct device *tty_dev;
- int ret;
- int port_num;
-
- coding.dwDTERate = cpu_to_le32(9600);
- coding.bCharFormat = 8;
- coding.bParityType = USB_CDC_NO_PARITY;
- coding.bDataBits = USB_CDC_1_STOP_BITS;
-
- for (port_num = 0; port_num < MAX_U_SERIAL_PORTS; port_num++) {
- ret = gs_port_alloc(port_num, &coding);
- if (ret == -EBUSY)
- continue;
- if (ret)
- return ret;
- break;
- }
- if (ret)
- return ret;
-
- /* ... and sysfs class devices, so mdev/udev make /dev/ttyGS* */
-
- tty_dev = tty_port_register_device(&ports[port_num].port->port,
- gs_tty_driver, port_num, NULL);
- if (IS_ERR(tty_dev)) {
- struct gs_port *port;
- pr_err("%s: failed to register tty for port %d, err %ld\n",
- __func__, port_num, PTR_ERR(tty_dev));
-
- ret = PTR_ERR(tty_dev);
- port = ports[port_num].port;
- ports[port_num].port = NULL;
- gserial_free_port(port);
- goto err;
- }
- *line_num = port_num;
- gserial_console_init();
-err:
- return ret;
-}
-EXPORT_SYMBOL_GPL(gserial_alloc_line);
-
-/**
- * gserial_connect - notify TTY I/O glue that USB link is active
- * @gser: the function, set up with endpoints and descriptors
- * @port_num: which port is active
- * Context: any (usually from irq)
- *
- * This is called activate endpoints and let the TTY layer know that
- * the connection is active ... not unlike "carrier detect". It won't
- * necessarily start I/O queues; unless the TTY is held open by any
- * task, there would be no point. However, the endpoints will be
- * activated so the USB host can perform I/O, subject to basic USB
- * hardware flow control.
- *
- * Caller needs to have set up the endpoints and USB function in @dev
- * before calling this, as well as the appropriate (speed-specific)
- * endpoint descriptors, and also have allocate @port_num by calling
- * @gserial_alloc_line().
- *
- * Returns negative errno or zero.
- * On success, ep->driver_data will be overwritten.
- */
-int gserial_connect(struct gserial *gser, u8 port_num)
-{
- struct gs_port *port;
- unsigned long flags;
- int status;
-
- if (port_num >= MAX_U_SERIAL_PORTS)
- return -ENXIO;
-
- port = ports[port_num].port;
- if (!port) {
- pr_err("serial line %d not allocated.\n", port_num);
- return -EINVAL;
- }
- if (port->port_usb) {
- pr_err("serial line %d is in use.\n", port_num);
- return -EBUSY;
- }
-
- /* activate the endpoints */
- status = usb_ep_enable(gser->in);
- if (status < 0)
- return status;
- gser->in->driver_data = port;
-
- status = usb_ep_enable(gser->out);
- if (status < 0)
- goto fail_out;
- gser->out->driver_data = port;
-
- /* then tell the tty glue that I/O can work */
- spin_lock_irqsave(&port->port_lock, flags);
- gser->ioport = port;
- port->port_usb = gser;
-
- /* REVISIT unclear how best to handle this state...
- * we don't really couple it with the Linux TTY.
- */
- gser->port_line_coding = port->port_line_coding;
-
- /* REVISIT if waiting on "carrier detect", signal. */
-
- /* if it's already open, start I/O ... and notify the serial
- * protocol about open/close status (connect/disconnect).
- */
- if (port->port.count) {
- pr_debug("gserial_connect: start ttyGS%d\n", port->port_num);
- gs_start_io(port);
- if (gser->connect)
- gser->connect(gser);
- } else {
- if (gser->disconnect)
- gser->disconnect(gser);
- }
-
- status = gs_console_connect(port_num);
- spin_unlock_irqrestore(&port->port_lock, flags);
-
- return status;
-
-fail_out:
- usb_ep_disable(gser->in);
- return status;
-}
-EXPORT_SYMBOL_GPL(gserial_connect);
-/**
- * gserial_disconnect - notify TTY I/O glue that USB link is inactive
- * @gser: the function, on which gserial_connect() was called
- * Context: any (usually from irq)
- *
- * This is called to deactivate endpoints and let the TTY layer know
- * that the connection went inactive ... not unlike "hangup".
- *
- * On return, the state is as if gserial_connect() had never been called;
- * there is no active USB I/O on these endpoints.
- */
-void gserial_disconnect(struct gserial *gser)
-{
- struct gs_port *port = gser->ioport;
- unsigned long flags;
-
- if (!port)
- return;
-
- /* tell the TTY glue not to do I/O here any more */
- spin_lock_irqsave(&port->port_lock, flags);
-
- /* REVISIT as above: how best to track this? */
- port->port_line_coding = gser->port_line_coding;
-
- port->port_usb = NULL;
- gser->ioport = NULL;
- if (port->port.count > 0 || port->openclose) {
- wake_up_interruptible(&port->drain_wait);
- if (port->port.tty)
- tty_hangup(port->port.tty);
- }
- spin_unlock_irqrestore(&port->port_lock, flags);
-
- /* disable endpoints, aborting down any active I/O */
- usb_ep_disable(gser->out);
- usb_ep_disable(gser->in);
-
- /* finally, free any unused/unusable I/O buffers */
- spin_lock_irqsave(&port->port_lock, flags);
- if (port->port.count == 0 && !port->openclose)
- gs_buf_free(&port->port_write_buf);
- gs_free_requests(gser->out, &port->read_pool, NULL);
- gs_free_requests(gser->out, &port->read_queue, NULL);
- gs_free_requests(gser->in, &port->write_pool, NULL);
-
- port->read_allocated = port->read_started =
- port->write_allocated = port->write_started = 0;
-
- gs_console_disconnect(gser->in);
- spin_unlock_irqrestore(&port->port_lock, flags);
-}
-EXPORT_SYMBOL_GPL(gserial_disconnect);
-
-static int userial_init(void)
-{
- unsigned i;
- int status;
-
- gs_tty_driver = alloc_tty_driver(MAX_U_SERIAL_PORTS);
- if (!gs_tty_driver)
- return -ENOMEM;
-
- gs_tty_driver->driver_name = "g_serial";
- gs_tty_driver->name = "ttyGS";
- /* uses dynamically assigned dev_t values */
-
- gs_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
- gs_tty_driver->subtype = SERIAL_TYPE_NORMAL;
- gs_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
- gs_tty_driver->init_termios = tty_std_termios;
-
- /* 9600-8-N-1 ... matches defaults expected by "usbser.sys" on
- * MS-Windows. Otherwise, most of these flags shouldn't affect
- * anything unless we were to actually hook up to a serial line.
- */
- gs_tty_driver->init_termios.c_cflag =
- B9600 | CS8 | CREAD | HUPCL | CLOCAL;
- gs_tty_driver->init_termios.c_ispeed = 9600;
- gs_tty_driver->init_termios.c_ospeed = 9600;
-
- tty_set_operations(gs_tty_driver, &gs_tty_ops);
- for (i = 0; i < MAX_U_SERIAL_PORTS; i++)
- mutex_init(&ports[i].lock);
-
- /* export the driver ... */
- status = tty_register_driver(gs_tty_driver);
- if (status) {
- pr_err("%s: cannot register, err %d\n",
- __func__, status);
- goto fail;
- }
-
- pr_debug("%s: registered %d ttyGS* device%s\n", __func__,
- MAX_U_SERIAL_PORTS,
- (MAX_U_SERIAL_PORTS == 1) ? "" : "s");
-
- return status;
-fail:
- put_tty_driver(gs_tty_driver);
- gs_tty_driver = NULL;
- return status;
-}
-module_init(userial_init);
-
-static void userial_cleanup(void)
-{
- tty_unregister_driver(gs_tty_driver);
- put_tty_driver(gs_tty_driver);
- gs_tty_driver = NULL;
-}
-module_exit(userial_cleanup);
-
-MODULE_LICENSE("GPL");
diff --git a/drivers/usb/gadget/function/u_serial.h b/drivers/usb/gadget/function/u_serial.h
deleted file mode 100644
index c20210c..0000000
--- a/drivers/usb/gadget/function/u_serial.h
+++ /dev/null
@@ -1,71 +0,0 @@
-/*
- * u_serial.h - interface to USB gadget "serial port"/TTY utilities
- *
- * Copyright (C) 2008 David Brownell
- * Copyright (C) 2008 by Nokia Corporation
- *
- * This software is distributed under the terms of the GNU General
- * Public License ("GPL") as published by the Free Software Foundation,
- * either version 2 of that License or (at your option) any later version.
- */
-
-#ifndef __U_SERIAL_H
-#define __U_SERIAL_H
-
-#include <linux/usb/composite.h>
-#include <linux/usb/cdc.h>
-
-#define MAX_U_SERIAL_PORTS 4
-
-struct f_serial_opts {
- struct usb_function_instance func_inst;
- u8 port_num;
-};
-
-/*
- * One non-multiplexed "serial" I/O port ... there can be several of these
- * on any given USB peripheral device, if it provides enough endpoints.
- *
- * The "u_serial" utility component exists to do one thing: manage TTY
- * style I/O using the USB peripheral endpoints listed here, including
- * hookups to sysfs and /dev for each logical "tty" device.
- *
- * REVISIT at least ACM could support tiocmget() if needed.
- *
- * REVISIT someday, allow multiplexing several TTYs over these endpoints.
- */
-struct gserial {
- struct usb_function func;
-
- /* port is managed by gserial_{connect,disconnect} */
- struct gs_port *ioport;
-
- struct usb_ep *in;
- struct usb_ep *out;
-
- /* REVISIT avoid this CDC-ACM support harder ... */
- struct usb_cdc_line_coding port_line_coding; /* 9600-8-N-1 etc */
-
- /* notification callbacks */
- void (*connect)(struct gserial *p);
- void (*disconnect)(struct gserial *p);
- int (*send_break)(struct gserial *p, int duration);
-};
-
-/* utilities to allocate/free request and buffer */
-struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t flags);
-void gs_free_req(struct usb_ep *, struct usb_request *req);
-
-/* management of individual TTY ports */
-int gserial_alloc_line(unsigned char *port_line);
-void gserial_free_line(unsigned char port_line);
-
-/* connect/disconnect is handled by individual functions */
-int gserial_connect(struct gserial *, u8 port_num);
-void gserial_disconnect(struct gserial *);
-
-/* functions are bound to configurations by a config or gadget driver */
-int gser_bind_config(struct usb_configuration *c, u8 port_num);
-int obex_bind_config(struct usb_configuration *c, u8 port_num);
-
-#endif /* __U_SERIAL_H */
diff --git a/drivers/usb/gadget/legacy/acm_ms.c b/drivers/usb/gadget/legacy/acm_ms.c
index c39de65..5c63b95 100644
--- a/drivers/usb/gadget/legacy/acm_ms.c
+++ b/drivers/usb/gadget/legacy/acm_ms.c
@@ -16,8 +16,7 @@
#include <linux/kernel.h>
#include <linux/module.h>
-
-#include "u_serial.h"
+#include <linux/usb/u_serial.h>
#define DRIVER_DESC "Composite Gadget (ACM + MS)"
#define DRIVER_VERSION "2011/10/10"
diff --git a/drivers/usb/gadget/legacy/cdc2.c b/drivers/usb/gadget/legacy/cdc2.c
index 51c0868..e06a88e 100644
--- a/drivers/usb/gadget/legacy/cdc2.c
+++ b/drivers/usb/gadget/legacy/cdc2.c
@@ -12,9 +12,9 @@
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/usb/u_serial.h>
#include "u_ether.h"
-#include "u_serial.h"
#include "u_ecm.h"
diff --git a/drivers/usb/gadget/legacy/dbgp.c b/drivers/usb/gadget/legacy/dbgp.c
index 99ca3da..ed8b9d4 100644
--- a/drivers/usb/gadget/legacy/dbgp.c
+++ b/drivers/usb/gadget/legacy/dbgp.c
@@ -12,8 +12,7 @@
#include <linux/module.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>
-
-#include "u_serial.h"
+#include <linux/usb/u_serial.h>
#define DRIVER_VENDOR_ID 0x0525 /* NetChip */
#define DRIVER_PRODUCT_ID 0xc0de /* undefined */
diff --git a/drivers/usb/gadget/legacy/multi.c b/drivers/usb/gadget/legacy/multi.c
index a70a406..335eea9 100644
--- a/drivers/usb/gadget/legacy/multi.c
+++ b/drivers/usb/gadget/legacy/multi.c
@@ -16,8 +16,8 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
+#include <linux/usb/u_serial.h>
-#include "u_serial.h"
#if defined USB_ETH_RNDIS
# undef USB_ETH_RNDIS
#endif
diff --git a/drivers/usb/gadget/legacy/nokia.c b/drivers/usb/gadget/legacy/nokia.c
index b1e535f..135f075 100644
--- a/drivers/usb/gadget/legacy/nokia.c
+++ b/drivers/usb/gadget/legacy/nokia.c
@@ -18,8 +18,8 @@
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
+#include <linux/usb/u_serial.h>
-#include "u_serial.h"
#include "u_ether.h"
#include "u_phonet.h"
#include "u_ecm.h"
diff --git a/drivers/usb/gadget/legacy/serial.c b/drivers/usb/gadget/legacy/serial.c
index 9d89adc..1ca8d58 100644
--- a/drivers/usb/gadget/legacy/serial.c
+++ b/drivers/usb/gadget/legacy/serial.c
@@ -15,8 +15,7 @@
#include <linux/module.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
-
-#include "u_serial.h"
+#include <linux/usb/u_serial.h>
/* Defines */
diff --git a/include/linux/usb/u_serial.h b/include/linux/usb/u_serial.h
new file mode 100644
index 0000000..c20210c
--- /dev/null
+++ b/include/linux/usb/u_serial.h
@@ -0,0 +1,71 @@
+/*
+ * u_serial.h - interface to USB gadget "serial port"/TTY utilities
+ *
+ * Copyright (C) 2008 David Brownell
+ * Copyright (C) 2008 by Nokia Corporation
+ *
+ * This software is distributed under the terms of the GNU General
+ * Public License ("GPL") as published by the Free Software Foundation,
+ * either version 2 of that License or (at your option) any later version.
+ */
+
+#ifndef __U_SERIAL_H
+#define __U_SERIAL_H
+
+#include <linux/usb/composite.h>
+#include <linux/usb/cdc.h>
+
+#define MAX_U_SERIAL_PORTS 4
+
+struct f_serial_opts {
+ struct usb_function_instance func_inst;
+ u8 port_num;
+};
+
+/*
+ * One non-multiplexed "serial" I/O port ... there can be several of these
+ * on any given USB peripheral device, if it provides enough endpoints.
+ *
+ * The "u_serial" utility component exists to do one thing: manage TTY
+ * style I/O using the USB peripheral endpoints listed here, including
+ * hookups to sysfs and /dev for each logical "tty" device.
+ *
+ * REVISIT at least ACM could support tiocmget() if needed.
+ *
+ * REVISIT someday, allow multiplexing several TTYs over these endpoints.
+ */
+struct gserial {
+ struct usb_function func;
+
+ /* port is managed by gserial_{connect,disconnect} */
+ struct gs_port *ioport;
+
+ struct usb_ep *in;
+ struct usb_ep *out;
+
+ /* REVISIT avoid this CDC-ACM support harder ... */
+ struct usb_cdc_line_coding port_line_coding; /* 9600-8-N-1 etc */
+
+ /* notification callbacks */
+ void (*connect)(struct gserial *p);
+ void (*disconnect)(struct gserial *p);
+ int (*send_break)(struct gserial *p, int duration);
+};
+
+/* utilities to allocate/free request and buffer */
+struct usb_request *gs_alloc_req(struct usb_ep *ep, unsigned len, gfp_t flags);
+void gs_free_req(struct usb_ep *, struct usb_request *req);
+
+/* management of individual TTY ports */
+int gserial_alloc_line(unsigned char *port_line);
+void gserial_free_line(unsigned char port_line);
+
+/* connect/disconnect is handled by individual functions */
+int gserial_connect(struct gserial *, u8 port_num);
+void gserial_disconnect(struct gserial *);
+
+/* functions are bound to configurations by a config or gadget driver */
+int gser_bind_config(struct usb_configuration *c, u8 port_num);
+int obex_bind_config(struct usb_configuration *c, u8 port_num);
+
+#endif /* __U_SERIAL_H */
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v2 3/4] usb: xhci: Add DbC support in xHCI driver
2017-08-07 8:07 [PATCH v2 0/4] usb: xhci: Add debug capability support in xhci Lu Baolu
2017-08-07 8:07 ` [PATCH v2 1/4] usb: xhci: Make some static functions global Lu Baolu
2017-08-07 8:07 ` [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common Lu Baolu
@ 2017-08-07 8:07 ` Lu Baolu
2017-08-07 8:07 ` [PATCH v2 4/4] usb: doc: Update document for USB3 debug port usage Lu Baolu
3 siblings, 0 replies; 9+ messages in thread
From: Lu Baolu @ 2017-08-07 8:07 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
xHCI compatible USB host controllers(i.e. super-speed USB3 controllers)
can be implemented with the Debug Capability(DbC). It presents a debug
device which is fully compliant with the USB framework and provides the
equivalent of a very high performance full-duplex serial link. The debug
capability operation model and registers interface are defined in 7.6.8
of the xHCI specification, revision 1.1.
The DbC debug device shares a root port with the xHCI host. By default,
the debug capability is disabled and the root port is assigned to xHCI.
When the DbC is enabled, the root port will be assigned to the DbC debug
device, and the xHCI sees nothing on this port. This implementation uses
a sysfs node named <dbc> under the xHCI device to manage the enabling
and disabling of the debug capability.
When the debug capability is enabled, it will present a debug device
through the debug port. This debug device is fully compliant with the
USB3 framework, and it can be enumerated by a debug host on the other
end of the USB link. As soon as the debug device is configured, a TTY
serial device named /dev/ttyGSn will be created.
One use of this link is running a login service on the debug target.
Hence it can be remote accessed by a debug host. Another use case can
probably be found in servers. It provides a peer-to-peer USB link
between two host-only machines. This provides a reasonable out-of-band
communication method between two servers.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
.../ABI/testing/sysfs-bus-pci-drivers-xhci_hcd | 25 +
drivers/usb/host/Kconfig | 9 +
drivers/usb/host/Makefile | 5 +
drivers/usb/host/xhci-dbgcap.c | 1100 ++++++++++++++++++++
drivers/usb/host/xhci-dbgcap.h | 194 ++++
drivers/usb/host/xhci-trace.h | 65 ++
drivers/usb/host/xhci.c | 10 +
drivers/usb/host/xhci.h | 1 +
include/linux/usb/gadget.h | 52 +
9 files changed, 1461 insertions(+)
create mode 100644 Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd
create mode 100644 drivers/usb/host/xhci-dbgcap.c
create mode 100644 drivers/usb/host/xhci-dbgcap.h
diff --git a/Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd b/Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd
new file mode 100644
index 0000000..0088aba
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-bus-pci-drivers-xhci_hcd
@@ -0,0 +1,25 @@
+What: /sys/bus/pci/drivers/xhci_hcd/.../dbc
+Date: June 2017
+Contact: Lu Baolu <baolu.lu@linux.intel.com>
+Description:
+ xHCI compatible USB host controllers (i.e. super-speed
+ USB3 controllers) are often implemented with the Debug
+ Capability (DbC). It can present a debug device which
+ is fully compliant with the USB framework and provides
+ the equivalent of a very high performance full-duplex
+ serial link for debug purpose.
+
+ The DbC debug device shares a root port with xHCI host.
+ When the DbC is enabled, the root port will be assigned
+ to the Debug Capability. Otherwise, it will be assigned
+ to xHCI.
+
+ Writing "enable" to this attribute will enable the DbC
+ functionality and the shared root port will be assigned
+ to the DbC device. Writing "disable" to this attribute
+ will disable the DbC functionality and the shared root
+ port will roll back to the xHCI.
+
+ Reading this attribute gives the state of the DbC. It
+ can be one of the following states: disabled, enabled,
+ initialized, connected, configured and stalled.
diff --git a/drivers/usb/host/Kconfig b/drivers/usb/host/Kconfig
index fa5692d..968a196 100644
--- a/drivers/usb/host/Kconfig
+++ b/drivers/usb/host/Kconfig
@@ -27,6 +27,15 @@ config USB_XHCI_HCD
module will be called xhci-hcd.
if USB_XHCI_HCD
+config USB_XHCI_DBGCAP
+ bool "xHCI support for debug capability"
+ depends on TTY
+ select USB_U_SERIAL
+ ---help---
+ Say 'Y' to enable the support for the xHCI debug capability. Make
+ sure that your xHCI host supports the extended debug capability and
+ you want a TTY serial device based on the xHCI debug capability
+ before enabling this option. If unsure, say 'N'.
config USB_XHCI_PCI
tristate
diff --git a/drivers/usb/host/Makefile b/drivers/usb/host/Makefile
index cf2691f..4629d20 100644
--- a/drivers/usb/host/Makefile
+++ b/drivers/usb/host/Makefile
@@ -13,6 +13,11 @@ fhci-$(CONFIG_FHCI_DEBUG) += fhci-dbg.o
xhci-hcd-y := xhci.o xhci-mem.o
xhci-hcd-y += xhci-ring.o xhci-hub.o xhci-dbg.o
xhci-hcd-y += xhci-trace.o
+
+ifneq ($(CONFIG_USB_XHCI_DBGCAP), )
+ xhci-hcd-y += xhci-dbgcap.o
+endif
+
ifneq ($(CONFIG_USB_XHCI_MTK), )
xhci-hcd-y += xhci-mtk-sch.o
endif
diff --git a/drivers/usb/host/xhci-dbgcap.c b/drivers/usb/host/xhci-dbgcap.c
new file mode 100644
index 0000000..6e5b505
--- /dev/null
+++ b/drivers/usb/host/xhci-dbgcap.c
@@ -0,0 +1,1100 @@
+/**
+ * xhci-dbgcap.c - xHCI debug capability support
+ *
+ * Copyright (C) 2017 Intel Corporation
+ *
+ * Author: Lu Baolu <baolu.lu@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/dma-mapping.h>
+#include <linux/slab.h>
+
+#include "xhci.h"
+#include "xhci-trace.h"
+#include "xhci-dbgcap.h"
+
+static inline void *
+dbc_dma_alloc_coherent(struct xhci_hcd *xhci, size_t size,
+ dma_addr_t *dma_handle, gfp_t flags)
+{
+ void *vaddr;
+
+ vaddr = dma_alloc_coherent(xhci_to_hcd(xhci)->self.sysdev,
+ size, dma_handle, flags);
+ memset(vaddr, 0, size);
+ return vaddr;
+}
+
+static inline void
+dbc_dma_free_coherent(struct xhci_hcd *xhci, size_t size,
+ void *cpu_addr, dma_addr_t dma_handle)
+{
+ if (cpu_addr)
+ dma_free_coherent(xhci_to_hcd(xhci)->self.sysdev,
+ size, cpu_addr, dma_handle);
+}
+
+static inline void xhci_put_utf16(u16 *s, const char *c)
+{
+ int i;
+ size_t size;
+
+ size = strlen(c);
+ for (i = 0; i < size; i++)
+ s[i] = cpu_to_le16(c[i]);
+}
+
+static u32 xhci_dbc_populate_strings(struct dbc_strings *strings)
+{
+ struct usb_string_descriptor *s_desc;
+ u32 string_length;
+
+ /* Serial string: */
+ s_desc = (struct usb_string_descriptor *)strings->serial;
+ xhci_put_utf16(s_desc->wData, DBC_STRING_SERIAL);
+
+ s_desc->bLength = (strlen(DBC_STRING_SERIAL) + 1) * 2;
+ s_desc->bDescriptorType = USB_DT_STRING;
+ string_length = s_desc->bLength;
+ string_length <<= 8;
+
+ /* Product string: */
+ s_desc = (struct usb_string_descriptor *)strings->product;
+ xhci_put_utf16(s_desc->wData, DBC_STRING_PRODUCT);
+
+ s_desc->bLength = (strlen(DBC_STRING_PRODUCT) + 1) * 2;
+ s_desc->bDescriptorType = USB_DT_STRING;
+ string_length += s_desc->bLength;
+ string_length <<= 8;
+
+ /* Manufacture string: */
+ s_desc = (struct usb_string_descriptor *)strings->manufacturer;
+ xhci_put_utf16(s_desc->wData, DBC_STRING_MANUFACTURER);
+
+ s_desc->bLength = (strlen(DBC_STRING_MANUFACTURER) + 1) * 2;
+ s_desc->bDescriptorType = USB_DT_STRING;
+ string_length += s_desc->bLength;
+ string_length <<= 8;
+
+ /* String0: */
+ strings->string0[0] = 4;
+ strings->string0[1] = USB_DT_STRING;
+ strings->string0[2] = 0x09;
+ strings->string0[3] = 0x04;
+ string_length += 4;
+
+ return string_length;
+}
+
+static void xhci_dbc_populate_contexts(struct xhci_hcd *xhci, u32 string_length)
+{
+ struct xhci_dbc *dbc;
+ struct dbc_info_context *info;
+ struct xhci_ep_ctx *ep_ctx;
+ u32 dev_info;
+ dma_addr_t deq, dma;
+ unsigned int max_burst;
+
+ dbc = xhci->dbc;
+ if (!dbc)
+ return;
+
+ /* Populate info Context: */
+ info = (struct dbc_info_context *)dbc->ctx->bytes;
+ dma = dbc->string_dma;
+ info->string0 = cpu_to_le64(dma);
+ info->manufacturer = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH);
+ info->product = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 2);
+ info->serial = cpu_to_le64(dma + DBC_MAX_STRING_LENGTH * 3);
+ info->length = cpu_to_le32(string_length);
+
+ /* Populate bulk out endpoint context: */
+ ep_ctx = dbc_bulkout_ctx(dbc);
+ max_burst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control));
+ deq = dbc_bulkout_enq(dbc);
+ ep_ctx->ep_info = 0;
+ ep_ctx->ep_info2 = dbc_epctx_info2(BULK_OUT_EP, 1024, max_burst);
+ ep_ctx->deq = cpu_to_le64(deq | dbc->ring_out->cycle_state);
+
+ /* Populate bulk in endpoint context: */
+ ep_ctx = dbc_bulkin_ctx(dbc);
+ deq = dbc_bulkin_enq(dbc);
+ ep_ctx->ep_info = 0;
+ ep_ctx->ep_info2 = dbc_epctx_info2(BULK_IN_EP, 1024, max_burst);
+ ep_ctx->deq = cpu_to_le64(deq | dbc->ring_in->cycle_state);
+
+ /* Set DbC context and info registers: */
+ xhci_write_64(xhci, dbc->ctx->dma, &dbc->regs->dccp);
+
+ dev_info = cpu_to_le32((DBC_VENDOR_ID << 16) | DBC_PROTOCOL);
+ writel(dev_info, &dbc->regs->devinfo1);
+
+ dev_info = cpu_to_le32((DBC_DEVICE_REV << 16) | DBC_PRODUCT_ID);
+ writel(dev_info, &dbc->regs->devinfo2);
+}
+
+static void xhci_dbc_giveback(struct dbc_request *dreq, int status)
+ __releases(&dbc->lock)
+ __acquires(&dbc->lock)
+{
+ struct dbc_ep *dep = dreq->dep;
+ struct usb_request *req = &dreq->request;
+ struct xhci_dbc *dbc = dep->dbc;
+ struct device *dev = xhci_to_hcd(dbc->xhci)->self.sysdev;
+
+ list_del_init(&dreq->list);
+ dreq->trb_dma = 0;
+ dreq->trb = NULL;
+
+ if (req->status == -EINPROGRESS)
+ req->status = status;
+
+ dma_unmap_single(dev,
+ req->dma,
+ req->length,
+ dbc_ep_dma_direction(dep));
+
+ /* Give back the transfer request: */
+ trace_xhci_dbc_giveback_request(dreq);
+ spin_unlock(&dbc->lock);
+ req->complete(&dep->ep, req);
+ spin_lock(&dbc->lock);
+}
+
+static void xhci_dbc_flush_single_request(struct dbc_request *dreq)
+{
+ union xhci_trb *trb = dreq->trb;
+
+ trb->generic.field[0] = 0;
+ trb->generic.field[1] = 0;
+ trb->generic.field[2] = 0;
+ trb->generic.field[3] &= cpu_to_le32(TRB_CYCLE);
+ trb->generic.field[3] |= cpu_to_le32(TRB_TYPE(TRB_TR_NOOP));
+
+ xhci_dbc_giveback(dreq, -ECONNRESET);
+}
+
+static void xhci_dbc_flush_endpoint_requests(struct dbc_ep *dep)
+{
+ struct dbc_request *dreq, *tmp;
+
+ list_for_each_entry_safe(dreq, tmp, &dep->pending_list, list)
+ xhci_dbc_flush_single_request(dreq);
+}
+
+static void xhci_dbc_flush_reqests(struct xhci_dbc *dbc)
+{
+ int i;
+ struct dbc_ep *dep;
+
+ for (i = BULK_OUT; i <= BULK_IN; i++) {
+ dep = dbc->eps[i];
+ xhci_dbc_flush_endpoint_requests(dep);
+ }
+}
+
+static int dbc_gadget_ep_enable(struct usb_ep *ep,
+ const struct usb_endpoint_descriptor *desc)
+{
+ struct dbc_ep *dep = ep_to_dep(ep);
+ struct xhci_dbc *dbc = dep->dbc;
+
+ return !(dbc->state == DS_CONFIGURED);
+}
+
+static int dbc_gadget_ep_disable(struct usb_ep *ep)
+{
+ struct dbc_ep *dep = ep_to_dep(ep);
+ struct xhci_dbc *dbc = dep->dbc;
+
+ spin_lock(&dbc->lock);
+ xhci_dbc_flush_reqests(dbc);
+ spin_unlock(&dbc->lock);
+
+ return 0;
+}
+
+static struct usb_request *
+dbc_gadget_ep_alloc_request(struct usb_ep *ep, gfp_t gfp_flags)
+{
+ struct dbc_request *dreq;
+ struct dbc_ep *dep = ep_to_dep(ep);
+
+ dreq = kzalloc(sizeof(*dreq), gfp_flags);
+ if (!dreq)
+ return NULL;
+
+ dreq->dep = dep;
+ INIT_LIST_HEAD(&dreq->list);
+
+ trace_xhci_dbc_alloc_request(dreq);
+
+ return &dreq->request;
+}
+
+static void
+dbc_gadget_ep_free_request(struct usb_ep *ep, struct usb_request *request)
+{
+ struct dbc_request *dreq = req_to_dreq(request);
+
+ trace_xhci_dbc_free_request(dreq);
+
+ kfree(dreq);
+}
+
+static void
+xhci_dbc_queue_trb(struct xhci_ring *ring, u32 field1,
+ u32 field2, u32 field3, u32 field4)
+{
+ union xhci_trb *trb, *next;
+
+ trb = ring->enqueue;
+ trb->generic.field[0] = cpu_to_le32(field1);
+ trb->generic.field[1] = cpu_to_le32(field2);
+ trb->generic.field[2] = cpu_to_le32(field3);
+ trb->generic.field[3] = cpu_to_le32(field4);
+
+ trace_xhci_dbc_gadget_ep_queue(ring, &trb->generic);
+
+ ring->num_trbs_free--;
+ next = ++(ring->enqueue);
+ if (TRB_TYPE_LINK_LE32(next->link.control)) {
+ next->link.control ^= cpu_to_le32(TRB_CYCLE);
+ ring->enqueue = ring->enq_seg->trbs;
+ ring->cycle_state ^= 1;
+ }
+}
+
+static int xhci_dbc_queue_bulk_tx(struct dbc_ep *dep,
+ struct dbc_request *dreq)
+{
+ u64 addr;
+ union xhci_trb *trb;
+ unsigned int num_trbs;
+ struct xhci_dbc *dbc = dep->dbc;
+ struct xhci_ring *ring = dep->ring;
+ struct usb_request *req = &dreq->request;
+ u32 length, control, cycle;
+
+ num_trbs = count_trbs(req->dma, req->length);
+ WARN_ON(num_trbs != 1);
+ if (ring->num_trbs_free < num_trbs)
+ return -EBUSY;
+
+ addr = req->dma;
+ trb = ring->enqueue;
+ cycle = ring->cycle_state;
+ length = TRB_LEN(req->length);
+ control = TRB_TYPE(TRB_NORMAL) | TRB_IOC;
+
+ if (cycle)
+ control &= cpu_to_le32(~TRB_CYCLE);
+ else
+ control |= cpu_to_le32(TRB_CYCLE);
+
+ dreq->trb = ring->enqueue;
+ dreq->trb_dma = xhci_trb_virt_to_dma(ring->enq_seg, ring->enqueue);
+ xhci_dbc_queue_trb(ring,
+ lower_32_bits(addr),
+ upper_32_bits(addr),
+ length, control);
+
+ /*
+ * Add a barrier between writes of trb fields and flipping
+ * the cycle bit:
+ */
+ wmb();
+
+ if (cycle)
+ trb->generic.field[3] |= cpu_to_le32(TRB_CYCLE);
+ else
+ trb->generic.field[3] &= cpu_to_le32(~TRB_CYCLE);
+
+ writel(DBC_DOOR_BELL_TARGET(dep->direction), &dbc->regs->doorbell);
+
+ return 0;
+}
+
+static int
+__dbc_gadget_ep_queue(struct dbc_ep *dep, struct dbc_request *dreq)
+{
+ int ret;
+ struct device *dev;
+ struct xhci_dbc *dbc = dep->dbc;
+ struct xhci_hcd *xhci = dbc->xhci;
+ struct usb_request *req = &dreq->request;
+
+ dev = xhci_to_hcd(xhci)->self.sysdev;
+
+ req->actual = 0;
+ req->status = -EINPROGRESS;
+
+ if (!req->length || !req->buf)
+ return -EINVAL;
+
+ req->dma = dma_map_single(dev,
+ req->buf,
+ req->length,
+ dbc_ep_dma_direction(dep));
+ if (dma_mapping_error(dev, req->dma)) {
+ xhci_err(xhci, "failed to map buffer\n");
+ return -EFAULT;
+ }
+
+ ret = xhci_dbc_queue_bulk_tx(dep, dreq);
+ if (ret) {
+ xhci_err(xhci, "failed to queue trbs\n");
+ dma_unmap_single(dev,
+ req->dma,
+ req->length,
+ dbc_ep_dma_direction(dep));
+ return -EFAULT;
+ }
+
+ list_add_tail(&dreq->list, &dep->pending_list);
+
+ return 0;
+}
+
+static int dbc_gadget_ep_queue(struct usb_ep *ep,
+ struct usb_request *request,
+ gfp_t gfp_flags)
+{
+ struct dbc_request *dreq = req_to_dreq(request);
+ struct dbc_ep *dep = ep_to_dep(ep);
+ struct xhci_dbc *dbc = dep->dbc;
+ int ret = -ECONNRESET;
+
+ spin_lock(&dbc->lock);
+ if (dbc->state == DS_CONFIGURED) {
+ ret = __dbc_gadget_ep_queue(dep, dreq);
+ trace_xhci_dbc_queue_request(dreq);
+ }
+ spin_unlock(&dbc->lock);
+
+ return ret;
+}
+
+static const struct usb_ep_ops xhci_dbc_gadget_ep_ops = {
+ .enable = dbc_gadget_ep_enable,
+ .disable = dbc_gadget_ep_disable,
+ .alloc_request = dbc_gadget_ep_alloc_request,
+ .free_request = dbc_gadget_ep_free_request,
+ .queue = dbc_gadget_ep_queue,
+};
+
+static inline struct dbc_ep *
+xhci_dbc_alloc_endpoint(struct xhci_hcd *xhci, bool direction, gfp_t flags)
+{
+ struct usb_ep *ep;
+ struct dbc_ep *dep;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ dep = kzalloc(sizeof(*dep), flags);
+ if (!dep)
+ return NULL;
+
+ ep = &dep->ep;
+ ep->name = direction ? "ep-dbc-in" : "ep-dbc-out";
+ ep->ops = &xhci_dbc_gadget_ep_ops;
+ ep->caps.type_bulk = 1;
+ ep->caps.dir_in = !direction;
+ ep->caps.dir_out = direction;
+ ep->maxpacket = DBC_MAX_PACKET;
+ ep->maxpacket_limit = DBC_MAX_PACKET;
+ ep->maxburst = DBC_CTRL_MAXBURST(readl(&dbc->regs->control));
+ dep->dbc = dbc;
+ dep->direction = direction;
+ dep->ring = direction ? dbc->ring_in : dbc->ring_out;
+
+ INIT_LIST_HEAD(&dep->pending_list);
+
+ return dep;
+}
+
+static int xhci_dbc_gadget_eps_init(struct xhci_hcd *xhci, gfp_t flags)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ dbc->eps[BULK_OUT] = xhci_dbc_alloc_endpoint(xhci, BULK_OUT, flags);
+ dbc->eps[BULK_IN] = xhci_dbc_alloc_endpoint(xhci, BULK_IN, flags);
+
+ if (!dbc->eps[BULK_OUT] || !dbc->eps[BULK_IN]) {
+ kfree(dbc->eps[BULK_OUT]);
+ kfree(dbc->eps[BULK_IN]);
+
+ return -ENOMEM;
+ }
+
+ dbc->gs_port.in = &dbc->eps[BULK_OUT]->ep;
+ dbc->gs_port.out = &dbc->eps[BULK_IN]->ep;
+
+ return 0;
+}
+
+static void xhci_dbc_gadget_eps_exit(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ kfree(dbc->gs_port.in);
+ kfree(dbc->gs_port.out);
+}
+
+static int xhci_dbc_mem_init(struct xhci_hcd *xhci, gfp_t flags)
+{
+ int ret;
+ dma_addr_t deq;
+ u32 string_length;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ /* Allocate various rings for events and transfers: */
+ dbc->ring_evt = xhci_ring_alloc(xhci, 1, 1, TYPE_EVENT, 0, flags);
+ if (!dbc->ring_evt)
+ goto evt_fail;
+
+ dbc->ring_in = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
+ if (!dbc->ring_in)
+ goto in_fail;
+
+ dbc->ring_out = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
+ if (!dbc->ring_out)
+ goto out_fail;
+
+ /* Allocate and populate ERST: */
+ ret = xhci_alloc_erst(xhci, dbc->ring_evt, &dbc->erst, flags);
+ if (ret)
+ goto erst_fail;
+
+ /* Allocate context data structure: */
+ dbc->ctx = xhci_alloc_container_ctx(xhci, XHCI_CTX_TYPE_DEVICE, flags);
+ if (!dbc->ctx)
+ goto ctx_fail;
+
+ /* Allocate the string table: */
+ dbc->string_size = sizeof(struct dbc_strings);
+ dbc->string = dbc_dma_alloc_coherent(xhci,
+ dbc->string_size,
+ &dbc->string_dma,
+ flags);
+ if (!dbc->string)
+ goto string_fail;
+
+ /* Setup ERST register: */
+ writel(dbc->erst.erst_size, &dbc->regs->ersts);
+ xhci_write_64(xhci, dbc->erst.erst_dma_addr, &dbc->regs->erstba);
+ deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg,
+ dbc->ring_evt->dequeue);
+ xhci_write_64(xhci, deq, &dbc->regs->erdp);
+
+ /* Setup strings and contexts: */
+ string_length = xhci_dbc_populate_strings(dbc->string);
+ xhci_dbc_populate_contexts(xhci, string_length);
+
+ mmiowb();
+
+ ret = xhci_dbc_gadget_eps_init(xhci, flags);
+ if (ret)
+ goto eps_init_fail;
+
+ dbc->state = DS_INITIALIZED;
+
+ return 0;
+
+eps_init_fail:
+ dbc_dma_free_coherent(xhci,
+ dbc->string_size,
+ dbc->string, dbc->string_dma);
+ dbc->string = NULL;
+string_fail:
+ xhci_free_container_ctx(xhci, dbc->ctx);
+ dbc->ctx = NULL;
+ctx_fail:
+ xhci_free_erst(xhci, &dbc->erst);
+erst_fail:
+ xhci_ring_free(xhci, dbc->ring_out);
+ dbc->ring_out = NULL;
+out_fail:
+ xhci_ring_free(xhci, dbc->ring_in);
+ dbc->ring_in = NULL;
+in_fail:
+ xhci_ring_free(xhci, dbc->ring_evt);
+ dbc->ring_evt = NULL;
+evt_fail:
+ return -ENOMEM;
+}
+
+static void xhci_dbc_mem_cleanup(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (!dbc)
+ return;
+
+ xhci_dbc_gadget_eps_exit(xhci);
+
+ if (dbc->string) {
+ dbc_dma_free_coherent(xhci,
+ dbc->string_size,
+ dbc->string, dbc->string_dma);
+ dbc->string = NULL;
+ }
+
+ xhci_free_container_ctx(xhci, dbc->ctx);
+ dbc->ctx = NULL;
+
+ xhci_free_erst(xhci, &dbc->erst);
+ xhci_ring_free(xhci, dbc->ring_out);
+ xhci_ring_free(xhci, dbc->ring_in);
+ xhci_ring_free(xhci, dbc->ring_evt);
+ dbc->ring_in = NULL;
+ dbc->ring_out = NULL;
+ dbc->ring_evt = NULL;
+}
+
+static void xhci_dbc_reset_debug_port(struct xhci_hcd *xhci)
+{
+ u32 val;
+ unsigned long flags;
+ int port_index;
+ __le32 __iomem **port_array;
+
+ spin_lock_irqsave(&xhci->lock, flags);
+
+ port_index = xhci->num_usb3_ports;
+ port_array = xhci->usb3_ports;
+ if (port_index <= 0) {
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ return;
+ }
+
+ while (port_index--) {
+ val = readl(port_array[port_index]);
+ if (!(val & PORT_CONNECT))
+ writel(val | PORT_RESET, port_array[port_index]);
+ }
+
+ spin_unlock_irqrestore(&xhci->lock, flags);
+}
+
+static int __xhci_dbc_start(struct xhci_hcd *xhci)
+{
+ int ret;
+ u32 ctrl;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (dbc->state != DS_DISABLED)
+ return -EINVAL;
+
+ writel(0, &dbc->regs->control);
+ ret = xhci_handshake(&dbc->regs->control,
+ DBC_CTRL_DBC_ENABLE,
+ 0, 1000);
+ if (ret)
+ return ret;
+
+ ret = xhci_dbc_mem_init(xhci, GFP_ATOMIC);
+ if (ret)
+ return ret;
+
+ ctrl = readl(&dbc->regs->control);
+ writel(ctrl | DBC_CTRL_DBC_ENABLE | DBC_CTRL_PORT_ENABLE,
+ &dbc->regs->control);
+ ret = xhci_handshake(&dbc->regs->control,
+ DBC_CTRL_DBC_ENABLE,
+ DBC_CTRL_DBC_ENABLE, 1000);
+ if (ret)
+ return ret;
+
+ xhci_dbc_reset_debug_port(xhci);
+ dbc->state = DS_ENABLED;
+
+ return 0;
+}
+
+static void __xhci_dbc_stop(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (dbc->state == DS_DISABLED)
+ return;
+
+ writel(0, &dbc->regs->control);
+ xhci_dbc_mem_cleanup(xhci);
+ dbc->state = DS_DISABLED;
+}
+
+static int xhci_dbc_start(struct xhci_hcd *xhci)
+{
+ int ret;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ WARN_ON(!dbc);
+
+ spin_lock(&dbc->lock);
+ ret = __xhci_dbc_start(xhci);
+ spin_unlock(&dbc->lock);
+
+ if (!ret) {
+ pm_runtime_get_sync(xhci_to_hcd(xhci)->self.controller);
+ ret = mod_delayed_work(system_wq, &dbc->event_work, 1);
+ }
+
+ return ret;
+}
+
+static void xhci_dbc_stop(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ WARN_ON(!dbc);
+
+ cancel_delayed_work_sync(&dbc->event_work);
+
+ if (dbc->gs_port_num != GSPORT_INVAL) {
+ gserial_disconnect(&dbc->gs_port);
+ gserial_free_line(dbc->gs_port_num);
+ dbc->gs_port_num = GSPORT_INVAL;
+ }
+
+ spin_lock(&dbc->lock);
+ __xhci_dbc_stop(xhci);
+ spin_unlock(&dbc->lock);
+
+ pm_runtime_put_sync(xhci_to_hcd(xhci)->self.controller);
+}
+
+static void
+dbc_handle_port_status(struct xhci_hcd *xhci, union xhci_trb *event)
+{
+ u32 portsc;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ portsc = readl(&dbc->regs->portsc);
+ if (portsc & DBC_PORTSC_CONN_CHANGE)
+ xhci_info(xhci, "DbC port connect change\n");
+
+ if (portsc & DBC_PORTSC_RESET_CHANGE)
+ xhci_info(xhci, "DbC port reset change\n");
+
+ if (portsc & DBC_PORTSC_LINK_CHANGE)
+ xhci_info(xhci, "DbC port link status change\n");
+
+ if (portsc & DBC_PORTSC_CONFIG_CHANGE)
+ xhci_info(xhci, "DbC config error change\n");
+
+ /* Port reset change bit will be cleared in other place: */
+ writel(portsc & ~DBC_PORTSC_RESET_CHANGE, &dbc->regs->portsc);
+}
+
+static void dbc_handle_tx_event(struct xhci_hcd *xhci, union xhci_trb *event)
+{
+ struct dbc_ep *dep;
+ struct usb_request *req;
+ struct xhci_ring *ring;
+ int ep_id;
+ int status;
+ u32 comp_code;
+ size_t remain_length;
+ struct dbc_request *dreq = NULL, *r;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ comp_code = GET_COMP_CODE(le32_to_cpu(event->generic.field[2]));
+ remain_length = EVENT_TRB_LEN(le32_to_cpu(event->generic.field[2]));
+ ep_id = TRB_TO_EP_ID(le32_to_cpu(event->generic.field[3]));
+ dep = (ep_id == EPID_OUT) ?
+ dbc->eps[BULK_OUT] : dbc->eps[BULK_IN];
+ ring = dep->ring;
+
+ switch (comp_code) {
+ case COMP_SUCCESS:
+ remain_length = 0;
+ /* FALLTHROUGH */
+ case COMP_SHORT_PACKET:
+ status = 0;
+ break;
+ case COMP_TRB_ERROR:
+ case COMP_BABBLE_DETECTED_ERROR:
+ case COMP_USB_TRANSACTION_ERROR:
+ case COMP_STALL_ERROR:
+ xhci_warn(xhci, "tx error %d detected\n", comp_code);
+ status = -comp_code;
+ break;
+ default:
+ xhci_err(xhci, "unknown tx error %d\n", comp_code);
+ status = -comp_code;
+ break;
+ }
+
+ /* Match the pending request: */
+ list_for_each_entry(r, &dep->pending_list, list) {
+ if (r->trb_dma == event->trans_event.buffer) {
+ dreq = r;
+ break;
+ }
+ }
+
+ if (!dreq) {
+ xhci_warn(xhci, "no matched request\n");
+ return;
+ }
+
+ trace_xhci_dbc_handle_transfer(ring, &dreq->trb->generic);
+
+ req = &dreq->request;
+ ring->num_trbs_free++;
+ req->actual = req->length - remain_length;
+ xhci_dbc_giveback(dreq, status);
+}
+
+static enum evtreturn __xhci_dbc_handle_events(struct xhci_dbc *dbc)
+{
+ dma_addr_t deq;
+ struct dbc_ep *dep;
+ union xhci_trb *evt;
+ u32 ctrl, portsc;
+ struct xhci_hcd *xhci = dbc->xhci;
+ bool update_erdp = false;
+
+ /* DbC state machine: */
+ switch (dbc->state) {
+ case DS_DISABLED:
+ case DS_INITIALIZED:
+
+ return EVT_ERR;
+ case DS_ENABLED:
+ portsc = readl(&dbc->regs->portsc);
+ if (portsc & DBC_PORTSC_CONN_STATUS) {
+ dbc->state = DS_CONNECTED;
+ xhci_info(xhci, "DbC connected\n");
+ }
+
+ return EVT_DONE;
+ case DS_CONNECTED:
+ ctrl = readl(&dbc->regs->control);
+ if (ctrl & DBC_CTRL_DBC_RUN) {
+ dbc->state = DS_CONFIGURED;
+ xhci_info(xhci, "DbC configured\n");
+ portsc = readl(&dbc->regs->portsc);
+ writel(portsc, &dbc->regs->portsc);
+ return EVT_GSER;
+ }
+
+ return EVT_DONE;
+ case DS_CONFIGURED:
+ /* Handle cable unplug event: */
+ portsc = readl(&dbc->regs->portsc);
+ if (!(portsc & DBC_PORTSC_PORT_ENABLED) &&
+ !(portsc & DBC_PORTSC_CONN_STATUS)) {
+ xhci_info(xhci, "DbC cable unplugged\n");
+ dbc->state = DS_ENABLED;
+ xhci_dbc_flush_reqests(dbc);
+
+ return EVT_DISC;
+ }
+
+ /* Handle debug port reset event: */
+ if (portsc & DBC_PORTSC_RESET_CHANGE) {
+ xhci_info(xhci, "DbC port reset\n");
+ writel(portsc, &dbc->regs->portsc);
+ dbc->state = DS_ENABLED;
+ xhci_dbc_flush_reqests(dbc);
+
+ return EVT_DISC;
+ }
+
+ /* Handle endpoint stall event: */
+ ctrl = readl(&dbc->regs->control);
+ if ((ctrl & DBC_CTRL_HALT_IN_TR) ||
+ (ctrl & DBC_CTRL_HALT_OUT_TR)) {
+ xhci_info(xhci, "DbC Endpoint stall\n");
+ dbc->state = DS_STALLED;
+
+ if (ctrl & DBC_CTRL_HALT_IN_TR) {
+ dep = dbc->eps[BULK_IN];
+ xhci_dbc_flush_endpoint_requests(dep);
+ }
+
+ if (ctrl & DBC_CTRL_HALT_OUT_TR) {
+ dep = dbc->eps[BULK_OUT];
+ xhci_dbc_flush_endpoint_requests(dep);
+ }
+
+ return EVT_DONE;
+ }
+
+ /* Clear DbC run change bit: */
+ if (ctrl & DBC_CTRL_DBC_RUN_CHANGE) {
+ writel(ctrl, &dbc->regs->control);
+ ctrl = readl(&dbc->regs->control);
+ }
+
+ break;
+ case DS_STALLED:
+ ctrl = readl(&dbc->regs->control);
+ if (!(ctrl & DBC_CTRL_HALT_IN_TR) &&
+ !(ctrl & DBC_CTRL_HALT_OUT_TR) &&
+ (ctrl & DBC_CTRL_DBC_RUN)) {
+ dbc->state = DS_CONFIGURED;
+ break;
+ }
+
+ return EVT_DONE;
+ default:
+ xhci_err(xhci, "Unknown DbC state %d\n", dbc->state);
+ break;
+ }
+
+ /* Handle the events in the event ring: */
+ evt = dbc->ring_evt->dequeue;
+ while ((le32_to_cpu(evt->event_cmd.flags) & TRB_CYCLE) ==
+ dbc->ring_evt->cycle_state) {
+ /*
+ * Add a barrier between reading the cycle flag and any
+ * reads of the event's flags/data below:
+ */
+ rmb();
+
+ trace_xhci_dbc_handle_event(dbc->ring_evt, &evt->generic);
+
+ switch (le32_to_cpu(evt->event_cmd.flags) & TRB_TYPE_BITMASK) {
+ case TRB_TYPE(TRB_PORT_STATUS):
+ dbc_handle_port_status(xhci, evt);
+ break;
+ case TRB_TYPE(TRB_TRANSFER):
+ dbc_handle_tx_event(xhci, evt);
+ break;
+ default:
+ break;
+ }
+
+ inc_deq(xhci, dbc->ring_evt);
+ evt = dbc->ring_evt->dequeue;
+ update_erdp = true;
+ }
+
+ /* Update event ring dequeue pointer: */
+ if (update_erdp) {
+ deq = xhci_trb_virt_to_dma(dbc->ring_evt->deq_seg,
+ dbc->ring_evt->dequeue);
+ xhci_write_64(xhci, deq, &dbc->regs->erdp);
+ }
+
+ return EVT_DONE;
+}
+
+static void xhci_dbc_handle_events(struct work_struct *work)
+{
+ int ret;
+ enum evtreturn evtr;
+ struct xhci_dbc *dbc;
+ struct xhci_hcd *xhci;
+
+ dbc = container_of(to_delayed_work(work), struct xhci_dbc, event_work);
+ xhci = dbc->xhci;
+
+ spin_lock(&dbc->lock);
+ evtr = __xhci_dbc_handle_events(dbc);
+ spin_unlock(&dbc->lock);
+
+ switch (evtr) {
+ case EVT_GSER:
+ ret = gserial_alloc_line(&dbc->gs_port_num);
+ if (ret) {
+ xhci_err(xhci, "failed to alloc tty line\n");
+ break;
+ }
+
+ ret = gserial_connect(&dbc->gs_port, dbc->gs_port_num);
+ if (ret) {
+ xhci_err(xhci, "failed to register DbC tty\n");
+ gserial_free_line(dbc->gs_port_num);
+ dbc->gs_port_num = GSPORT_INVAL;
+ break;
+ }
+ xhci_info(xhci, "DbC now attached to /dev/ttyGS%d\n",
+ dbc->gs_port_num);
+ mod_delayed_work(system_wq, &dbc->event_work, 1);
+ break;
+ case EVT_DISC:
+ gserial_disconnect(&dbc->gs_port);
+ gserial_free_line(dbc->gs_port_num);
+ dbc->gs_port_num = GSPORT_INVAL;
+
+ mod_delayed_work(system_wq, &dbc->event_work, 1);
+ break;
+ case EVT_DONE:
+ mod_delayed_work(system_wq, &dbc->event_work, 1);
+ break;
+ default:
+ xhci_info(xhci, "stop handling dbc events\n");
+ }
+}
+
+static void xhci_dbc_exit(struct xhci_hcd *xhci)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&xhci->lock, flags);
+ kfree(xhci->dbc);
+ xhci->dbc = NULL;
+ spin_unlock_irqrestore(&xhci->lock, flags);
+}
+
+static int xhci_dbc_init(struct xhci_hcd *xhci)
+{
+ u32 reg;
+ struct xhci_dbc *dbc;
+ unsigned long flags;
+ void __iomem *base;
+ int dbc_cap_offs;
+
+ base = &xhci->cap_regs->hc_capbase;
+ dbc_cap_offs = xhci_find_next_ext_cap(base, 0, XHCI_EXT_CAPS_DEBUG);
+ if (!dbc_cap_offs)
+ return -ENODEV;
+
+ dbc = kzalloc(sizeof(*dbc), GFP_KERNEL);
+ if (!dbc)
+ return -ENOMEM;
+
+ dbc->regs = base + dbc_cap_offs;
+
+ /* We will avoid using DbC in xhci driver if it's in use. */
+ reg = readl(&dbc->regs->control);
+ if (reg & DBC_CTRL_DBC_ENABLE) {
+ kfree(dbc);
+ return -EBUSY;
+ }
+
+ spin_lock_irqsave(&xhci->lock, flags);
+ if (xhci->dbc) {
+ spin_unlock_irqrestore(&xhci->lock, flags);
+ kfree(dbc);
+ return -EBUSY;
+ }
+ xhci->dbc = dbc;
+ spin_unlock_irqrestore(&xhci->lock, flags);
+
+ dbc->xhci = xhci;
+ INIT_DELAYED_WORK(&dbc->event_work, xhci_dbc_handle_events);
+ spin_lock_init(&dbc->lock);
+ dbc->gs_port_num = GSPORT_INVAL;
+
+ return 0;
+}
+
+static ssize_t dbc_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ const char *p;
+ struct xhci_dbc *dbc;
+ struct xhci_hcd *xhci;
+
+ xhci = hcd_to_xhci(dev_get_drvdata(dev));
+ dbc = xhci->dbc;
+
+ switch (dbc->state) {
+ case DS_DISABLED:
+ p = "disabled";
+ break;
+ case DS_INITIALIZED:
+ p = "initialized";
+ break;
+ case DS_ENABLED:
+ p = "enabled";
+ break;
+ case DS_CONNECTED:
+ p = "connected";
+ break;
+ case DS_CONFIGURED:
+ p = "configured";
+ break;
+ case DS_STALLED:
+ p = "stalled";
+ break;
+ default:
+ p = "unknown";
+ }
+
+ return sprintf(buf, "%s\n", p);
+}
+
+static ssize_t dbc_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct xhci_dbc *dbc;
+ struct xhci_hcd *xhci;
+
+ xhci = hcd_to_xhci(dev_get_drvdata(dev));
+ dbc = xhci->dbc;
+
+ if (!strncmp(buf, "enable", 6))
+ xhci_dbc_start(xhci);
+ else if (!strncmp(buf, "disable", 7))
+ xhci_dbc_stop(xhci);
+ else
+ return -EINVAL;
+
+ return count;
+}
+
+static DEVICE_ATTR(dbc, 0644, dbc_show, dbc_store);
+
+int dbc_create_sysfs_file(struct xhci_hcd *xhci)
+{
+ int ret;
+ struct device *dev = xhci_to_hcd(xhci)->self.controller;
+
+ ret = xhci_dbc_init(xhci);
+ if (ret)
+ return ret;
+
+ return device_create_file(dev, &dev_attr_dbc);
+}
+
+void dbc_remove_sysfs_file(struct xhci_hcd *xhci)
+{
+ struct device *dev = xhci_to_hcd(xhci)->self.controller;
+
+ device_remove_file(dev, &dev_attr_dbc);
+ xhci_dbc_stop(xhci);
+ xhci_dbc_exit(xhci);
+}
+
+#ifdef CONFIG_PM
+int xhci_dbc_suspend(struct xhci_hcd *xhci)
+{
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (!dbc)
+ return 0;
+
+ if (dbc->state == DS_CONFIGURED)
+ dbc->resume_required = 1;
+
+ xhci_dbc_stop(xhci);
+
+ return 0;
+}
+
+int xhci_dbc_resume(struct xhci_hcd *xhci)
+{
+ int ret = 0;
+ struct xhci_dbc *dbc = xhci->dbc;
+
+ if (!dbc)
+ return 0;
+
+ if (dbc->resume_required) {
+ dbc->resume_required = 0;
+ xhci_dbc_start(xhci);
+ }
+
+ return ret;
+}
+#endif /* CONFIG_PM */
diff --git a/drivers/usb/host/xhci-dbgcap.h b/drivers/usb/host/xhci-dbgcap.h
new file mode 100644
index 0000000..4df8db3
--- /dev/null
+++ b/drivers/usb/host/xhci-dbgcap.h
@@ -0,0 +1,194 @@
+
+/**
+ * xhci-dbgcap.h - xHCI debug capability support
+ *
+ * Copyright (C) 2017 Intel Corporation
+ *
+ * Author: Lu Baolu <baolu.lu@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __LINUX_XHCI_DBGCAP_H
+#define __LINUX_XHCI_DBGCAP_H
+
+#include <linux/usb/gadget.h>
+#include <linux/usb/u_serial.h>
+
+struct dbc_regs {
+ __le32 capability;
+ __le32 doorbell;
+ __le32 ersts; /* Event Ring Segment Table Size*/
+ __le32 __reserved_0; /* 0c~0f reserved bits */
+ __le64 erstba; /* Event Ring Segment Table Base Address */
+ __le64 erdp; /* Event Ring Dequeue Pointer */
+ __le32 control;
+ __le32 status;
+ __le32 portsc; /* Port status and control */
+ __le32 __reserved_1; /* 2b~28 reserved bits */
+ __le64 dccp; /* Debug Capability Context Pointer */
+ __le32 devinfo1; /* Device Descriptor Info Register 1 */
+ __le32 devinfo2; /* Device Descriptor Info Register 2 */
+};
+
+struct dbc_info_context {
+ __le64 string0;
+ __le64 manufacturer;
+ __le64 product;
+ __le64 serial;
+ __le32 length;
+ __le32 __reserved_0[7];
+};
+
+#define DBC_CTRL_DBC_RUN BIT(0)
+#define DBC_CTRL_PORT_ENABLE BIT(1)
+#define DBC_CTRL_HALT_OUT_TR BIT(2)
+#define DBC_CTRL_HALT_IN_TR BIT(3)
+#define DBC_CTRL_DBC_RUN_CHANGE BIT(4)
+#define DBC_CTRL_DBC_ENABLE BIT(31)
+#define DBC_CTRL_MAXBURST(p) (((p) >> 16) & 0xff)
+#define DBC_DOOR_BELL_TARGET(p) (((p) & 0xff) << 8)
+
+#define DBC_MAX_PACKET 1024
+#define DBC_MAX_STRING_LENGTH 64
+#define DBC_STRING_MANUFACTURER "Linux"
+#define DBC_STRING_PRODUCT "Remote GDB"
+#define DBC_STRING_SERIAL "0001"
+#define DBC_CONTEXT_SIZE 64
+
+/*
+ * Port status:
+ */
+#define DBC_PORTSC_CONN_STATUS BIT(0)
+#define DBC_PORTSC_PORT_ENABLED BIT(1)
+#define DBC_PORTSC_CONN_CHANGE BIT(17)
+#define DBC_PORTSC_RESET_CHANGE BIT(21)
+#define DBC_PORTSC_LINK_CHANGE BIT(22)
+#define DBC_PORTSC_CONFIG_CHANGE BIT(23)
+
+struct dbc_strings {
+ char string0[DBC_MAX_STRING_LENGTH];
+ char manufacturer[DBC_MAX_STRING_LENGTH];
+ char product[DBC_MAX_STRING_LENGTH];
+ char serial[DBC_MAX_STRING_LENGTH];
+};
+
+#define DBC_PROTOCOL 1 /* GNU Remote Debug Command */
+#define DBC_VENDOR_ID 0x1d6b /* Linux Foundation 0x1d6b */
+#define DBC_PRODUCT_ID 0x0004 /* device 0004 */
+#define DBC_DEVICE_REV 0x0010 /* 0.10 */
+
+enum dbc_state {
+ DS_DISABLED = 0,
+ DS_INITIALIZED,
+ DS_ENABLED,
+ DS_CONNECTED,
+ DS_CONFIGURED,
+ DS_STALLED,
+};
+
+struct dbc_ep {
+ struct usb_ep ep;
+ struct xhci_dbc *dbc;
+ struct list_head pending_list;
+ struct xhci_ring *ring;
+
+ unsigned direction:1;
+};
+
+struct dbc_request {
+ struct usb_request request;
+ struct dbc_ep *dep;
+ struct list_head list;
+ dma_addr_t trb_dma;
+ union xhci_trb *trb;
+
+ unsigned direction:1;
+};
+
+#define ep_to_dep(e) (container_of(e, struct dbc_ep, ep))
+#define req_to_dreq(r) (container_of(r, struct dbc_request, request))
+
+/*
+ * Private structure for DbC hardware state:
+ */
+struct xhci_dbc {
+ struct xhci_hcd *xhci;
+ struct dbc_regs __iomem *regs;
+ struct xhci_ring *ring_evt;
+ struct xhci_ring *ring_in;
+ struct xhci_ring *ring_out;
+ struct xhci_erst erst;
+ struct xhci_container_ctx *ctx;
+
+ struct dbc_strings *string;
+ dma_addr_t string_dma;
+ size_t string_size;
+
+ enum dbc_state state;
+ struct delayed_work event_work;
+ unsigned resume_required:1;
+
+ unsigned char gs_port_num;
+ struct gserial gs_port;
+ struct dbc_ep *eps[2];
+
+ /* device lock */
+ spinlock_t lock;
+};
+
+#define dbc_bulkout_ctx(d) \
+ ((struct xhci_ep_ctx *)((d)->ctx->bytes + DBC_CONTEXT_SIZE))
+#define dbc_bulkin_ctx(d) \
+ ((struct xhci_ep_ctx *)((d)->ctx->bytes + DBC_CONTEXT_SIZE * 2))
+#define dbc_bulkout_enq(d) \
+ xhci_trb_virt_to_dma((d)->ring_out->enq_seg, (d)->ring_out->enqueue)
+#define dbc_bulkin_enq(d) \
+ xhci_trb_virt_to_dma((d)->ring_in->enq_seg, (d)->ring_in->enqueue)
+#define dbc_epctx_info2(t, p, b) \
+ cpu_to_le32(EP_TYPE(t) | MAX_PACKET(p) | MAX_BURST(b))
+#define dbc_ep_dma_direction(d) \
+ ((d)->direction ? DMA_FROM_DEVICE : DMA_TO_DEVICE)
+
+#define GSPORT_INVAL ((unsigned char)(-1))
+#define BULK_OUT 0
+#define BULK_IN 1
+#define EPID_OUT 2
+#define EPID_IN 3
+
+enum evtreturn {
+ EVT_ERR = -1,
+ EVT_DONE,
+ EVT_GSER,
+ EVT_DISC,
+};
+
+#ifdef CONFIG_USB_XHCI_DBGCAP
+int dbc_create_sysfs_file(struct xhci_hcd *xhci);
+void dbc_remove_sysfs_file(struct xhci_hcd *xhci);
+#ifdef CONFIG_PM
+int xhci_dbc_suspend(struct xhci_hcd *xhci);
+int xhci_dbc_resume(struct xhci_hcd *xhci);
+#endif /* CONFIG_PM */
+#else
+static inline int dbc_create_sysfs_file(struct xhci_hcd *xhci)
+{
+ return 0;
+}
+
+static inline void dbc_remove_sysfs_file(struct xhci_hcd *xhci)
+{
+}
+
+static inline int xhci_dbc_suspend(struct xhci_hcd *xhci)
+{
+ return 0;
+}
+
+static inline int xhci_dbc_resume(struct xhci_hcd *xhci)
+{
+ return 0;
+}
+#endif /* CONFIG_USB_XHCI_DBGCAP */
+#endif /* __LINUX_XHCI_DBGCAP_H */
diff --git a/drivers/usb/host/xhci-trace.h b/drivers/usb/host/xhci-trace.h
index 8ce96de..5b3b1b0 100644
--- a/drivers/usb/host/xhci-trace.h
+++ b/drivers/usb/host/xhci-trace.h
@@ -26,6 +26,7 @@
#include <linux/tracepoint.h>
#include "xhci.h"
+#include "xhci-dbgcap.h"
#define XHCI_MSG_MAX 500
@@ -158,6 +159,21 @@ DEFINE_EVENT(xhci_log_trb, xhci_queue_trb,
TP_ARGS(ring, trb)
);
+DEFINE_EVENT(xhci_log_trb, xhci_dbc_handle_event,
+ TP_PROTO(struct xhci_ring *ring, struct xhci_generic_trb *trb),
+ TP_ARGS(ring, trb)
+);
+
+DEFINE_EVENT(xhci_log_trb, xhci_dbc_handle_transfer,
+ TP_PROTO(struct xhci_ring *ring, struct xhci_generic_trb *trb),
+ TP_ARGS(ring, trb)
+);
+
+DEFINE_EVENT(xhci_log_trb, xhci_dbc_gadget_ep_queue,
+ TP_PROTO(struct xhci_ring *ring, struct xhci_generic_trb *trb),
+ TP_ARGS(ring, trb)
+);
+
DECLARE_EVENT_CLASS(xhci_log_virt_dev,
TP_PROTO(struct xhci_virt_device *vdev),
TP_ARGS(vdev),
@@ -453,6 +469,55 @@ DEFINE_EVENT(xhci_log_ring, xhci_inc_deq,
TP_PROTO(struct xhci_ring *ring),
TP_ARGS(ring)
);
+
+DECLARE_EVENT_CLASS(xhci_dbc_log_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req),
+ TP_STRUCT__entry(
+ __dynamic_array(char, name, XHCI_MSG_MAX)
+ __field(struct dbc_request *, req)
+ __field(unsigned int, actual)
+ __field(unsigned int, length)
+ __field(int, status)
+ ),
+ TP_fast_assign(
+ snprintf(__get_str(name), XHCI_MSG_MAX,
+ "%s", req->dep->ep.name);
+ __entry->req = req;
+ __entry->actual = req->request.actual;
+ __entry->length = req->request.length;
+ __entry->status = req->request.status;
+ ),
+ TP_printk("%s: req %p length %u/%u ==> %d",
+ __get_str(name), __entry->req, __entry->actual,
+ __entry->length, __entry->status
+ )
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_alloc_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_free_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_queue_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_dequeue_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
+
+DEFINE_EVENT(xhci_dbc_log_request, xhci_dbc_giveback_request,
+ TP_PROTO(struct dbc_request *req),
+ TP_ARGS(req)
+);
#endif /* __XHCI_TRACE_H */
/* this part must be outside header guard */
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index b2ff1ff..39a9a88 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -32,6 +32,7 @@
#include "xhci.h"
#include "xhci-trace.h"
#include "xhci-mtk.h"
+#include "xhci-dbgcap.h"
#define DRIVER_AUTHOR "Sarah Sharp"
#define DRIVER_DESC "'eXtensible' Host Controller (xHC) Driver"
@@ -632,6 +633,9 @@ int xhci_run(struct usb_hcd *hcd)
}
xhci_dbg_trace(xhci, trace_xhci_dbg_init,
"Finished xhci_run for USB2 roothub");
+
+ dbc_create_sysfs_file(xhci);
+
return 0;
}
EXPORT_SYMBOL_GPL(xhci_run);
@@ -660,6 +664,8 @@ static void xhci_stop(struct usb_hcd *hcd)
return;
}
+ dbc_remove_sysfs_file(xhci);
+
spin_lock_irq(&xhci->lock);
xhci->xhc_state |= XHCI_STATE_HALTED;
xhci->cmd_ring_state = CMD_RING_STATE_STOPPED;
@@ -876,6 +882,8 @@ int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
xhci->shared_hcd->state != HC_STATE_SUSPENDED)
return -EINVAL;
+ xhci_dbc_suspend(xhci);
+
/* Clear root port wake on bits if wakeup not allowed. */
if (!do_wakeup)
xhci_disable_port_wake_on_bits(xhci);
@@ -1071,6 +1079,8 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
spin_unlock_irq(&xhci->lock);
+ xhci_dbc_resume(xhci);
+
done:
if (retval == 0) {
/* Resume root hubs only when have pending events. */
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 62bcdcd..bae2538 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1850,6 +1850,7 @@ struct xhci_hcd {
/* Compliance Mode Timer Triggered every 2 seconds */
#define COMP_MODE_RCVRY_MSECS 2000
+ void *dbc;
/* platform-specific data -- must come last */
unsigned long priv[0] __aligned(sizeof(s64));
};
diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
index 1a4a4ba..e93ada1 100644
--- a/include/linux/usb/gadget.h
+++ b/include/linux/usb/gadget.h
@@ -243,6 +243,58 @@ int usb_ep_clear_halt(struct usb_ep *ep);
int usb_ep_set_wedge(struct usb_ep *ep);
int usb_ep_fifo_status(struct usb_ep *ep);
void usb_ep_fifo_flush(struct usb_ep *ep);
+#elif IS_ENABLED(CONFIG_USB_XHCI_DBGCAP)
+static inline void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
+ unsigned maxpacket_limit)
+{ }
+static inline int usb_ep_enable(struct usb_ep *ep)
+{
+ int ret = 0;
+
+ ret = ep->ops->enable(ep, ep->desc);
+ if (!ret)
+ ep->enabled = true;
+
+ return ret;
+}
+static inline int usb_ep_disable(struct usb_ep *ep)
+{
+ int ret = 0;
+
+ ret = ep->ops->disable(ep);
+ if (!ret)
+ ep->enabled = false;
+
+ return ret;
+}
+static inline struct usb_request *usb_ep_alloc_request(struct usb_ep *ep,
+ gfp_t gfp_flags)
+{
+ return ep->ops->alloc_request(ep, gfp_flags);
+}
+
+static inline void usb_ep_free_request(struct usb_ep *ep,
+ struct usb_request *req)
+{
+ ep->ops->free_request(ep, req);
+}
+static inline int usb_ep_queue(struct usb_ep *ep, struct usb_request *req,
+ gfp_t gfp_flags)
+{
+ return ep->ops->queue(ep, req, gfp_flags);
+}
+static inline int usb_ep_dequeue(struct usb_ep *ep, struct usb_request *req)
+{ return 0; }
+static inline int usb_ep_set_halt(struct usb_ep *ep)
+{ return 0; }
+static inline int usb_ep_clear_halt(struct usb_ep *ep)
+{ return 0; }
+static inline int usb_ep_set_wedge(struct usb_ep *ep)
+{ return 0; }
+static inline int usb_ep_fifo_status(struct usb_ep *ep)
+{ return 0; }
+static inline void usb_ep_fifo_flush(struct usb_ep *ep)
+{ }
#else
static inline void usb_ep_set_maxpacket_limit(struct usb_ep *ep,
unsigned maxpacket_limit)
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH v2 4/4] usb: doc: Update document for USB3 debug port usage
2017-08-07 8:07 [PATCH v2 0/4] usb: xhci: Add debug capability support in xhci Lu Baolu
` (2 preceding siblings ...)
2017-08-07 8:07 ` [PATCH v2 3/4] usb: xhci: Add DbC support in xHCI driver Lu Baolu
@ 2017-08-07 8:07 ` Lu Baolu
3 siblings, 0 replies; 9+ messages in thread
From: Lu Baolu @ 2017-08-07 8:07 UTC (permalink / raw)
To: Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel, Lu Baolu
Update Documentation/driver-api/usb/usb3-debug-port.rst. This update
includes the guide for using xHCI debug capability based TTY serial
link.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
Documentation/driver-api/usb/usb3-debug-port.rst | 68 ++++++++++++++++++++++++
1 file changed, 68 insertions(+)
diff --git a/Documentation/driver-api/usb/usb3-debug-port.rst b/Documentation/driver-api/usb/usb3-debug-port.rst
index feb1a36..e4bb02e 100644
--- a/Documentation/driver-api/usb/usb3-debug-port.rst
+++ b/Documentation/driver-api/usb/usb3-debug-port.rst
@@ -98,3 +98,71 @@ you to check the sanity of the setup.
cat /dev/ttyUSB0
done
===== end of bash scripts ===============
+
+Serial TTY
+==========
+
+DbC has also been designed for a serial TTY device at runtime.
+One use of this is running a login service on the debug target.
+Hence it can be remote accessed by the debug host. Another use
+can probably be found in servers. It provides a peer-to-peer USB
+link between two host-only machines. This provides a reasonable
+out-of-band communication method between two servers.
+
+In order to use this, you need to make sure your kernel has been
+configured to support USB_XHCI_DBGCAP. A sysfs attribute under
+the xHCI device node is used to enable or disable DbC. By default,
+DbC is disabled::
+
+ root@target:/sys/bus/pci/devices/0000:00:14.0# cat dbc
+ disabled
+
+Enable DbC with the following command::
+
+ root@target:/sys/bus/pci/devices/0000:00:14.0# echo enable > dbc
+
+You can check the DbC state at anytime::
+
+ root@target:/sys/bus/pci/devices/0000:00:14.0# cat dbc
+ enabled
+
+Connect the debug target to the debug host with a USB 3.0 super-
+speed A-to-A debugging cable. You can see the /dev/ttyGSn created
+on the debug target. You will see below kernel message lines::
+
+ root@target: tail -f /var/log/kern.log
+ [ 182.730103] xhci_hcd 0000:00:14.0: DbC connected
+ [ 191.169420] xhci_hcd 0000:00:14.0: DbC configured
+ [ 191.169597] xhci_hcd 0000:00:14.0: DbC now attached to /dev/ttyGS0
+
+Accordingly, the DbC state has been brought up to::
+
+ root@host:/sys/bus/pci/devices/0000:00:14.0# cat dbc
+ configured
+
+On the debug host, you will see the debug device has been enumerated.
+You will see below kernel message lines::
+
+ root@host: tail -f /var/log/kern.log
+ [ 79.454780] usb 2-2.1: new SuperSpeed USB device number 3 using xhci_hcd
+ [ 79.475003] usb 2-2.1: LPM exit latency is zeroed, disabling LPM.
+ [ 79.475389] usb 2-2.1: New USB device found, idVendor=1d6b, idProduct=0004
+ [ 79.475390] usb 2-2.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
+ [ 79.475391] usb 2-2.1: Product: Remote GDB
+ [ 79.475392] usb 2-2.1: Manufacturer: Linux
+ [ 79.475393] usb 2-2.1: SerialNumber: 0001
+ [ 79.660368] usb_debug 2-2.1:1.0: xhci_dbc converter detected
+ [ 79.660439] usb 2-2.1: xhci_dbc converter now attached to ttyUSB0
+
+You can simply verify whether it works by::
+
+ # On target side
+ root@target: echo "Hello world" > /dev/ttyGS0
+
+ # On host side
+ root@host: cat /dev/ttyUSB0
+ Hello world
+
+ # vice versa
+
+You have a workable serial link over USB now.
--
2.7.4
^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common
2017-08-07 8:07 ` [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common Lu Baolu
@ 2017-08-07 8:13 ` Felipe Balbi
2017-08-08 1:25 ` Lu Baolu
0 siblings, 1 reply; 9+ messages in thread
From: Felipe Balbi @ 2017-08-07 8:13 UTC (permalink / raw)
To: Lu Baolu, Mathias Nyman, Greg Kroah-Hartman
Cc: linux-usb, linux-kernel, Lu Baolu
[-- Attachment #1: Type: text/plain, Size: 1130 bytes --]
Hi,
Lu Baolu <baolu.lu@linux.intel.com> writes:
> The component u_serial provides a glue layer between TTY layer
> and a USB gadget device needed to provide a basic serial port
> functionality. Currently, u_serial sits under gadget/function
> and depends on CONFIG_USB_GADGET to be compiled and used.
>
> Most of the serial gadget devices are based on a UDC (USB device
> controller) and implemented by making use of the Linux gadget
> frameworks. But we are facing other implementions as well. One
> example can be found with xHCI debug capability. The xHCI debug
> capability implements a serial gadget with hardware and firmware,
> and provides an interface similar with xHCI host for submitting
> and reaping the transfer requests.
>
> In order to make better use of u_serial when implementing xHCI
> debug capability in xHCI driver, this patch moves u_serial.c
> from gadget/function to usb/common, and moves u_serial.h from
> gadget/function to include/linux/usb.
>
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
NAK, u_serial uses the gadget API. It's definitely not COMMON.
--
balbi
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 832 bytes --]
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common
2017-08-07 8:13 ` Felipe Balbi
@ 2017-08-08 1:25 ` Lu Baolu
2017-08-08 6:14 ` Felipe Balbi
0 siblings, 1 reply; 9+ messages in thread
From: Lu Baolu @ 2017-08-08 1:25 UTC (permalink / raw)
To: Felipe Balbi, Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel
Hi,
On 08/07/2017 04:13 PM, Felipe Balbi wrote:
> Hi,
>
> Lu Baolu <baolu.lu@linux.intel.com> writes:
>> The component u_serial provides a glue layer between TTY layer
>> and a USB gadget device needed to provide a basic serial port
>> functionality. Currently, u_serial sits under gadget/function
>> and depends on CONFIG_USB_GADGET to be compiled and used.
>>
>> Most of the serial gadget devices are based on a UDC (USB device
>> controller) and implemented by making use of the Linux gadget
>> frameworks. But we are facing other implementions as well. One
>> example can be found with xHCI debug capability. The xHCI debug
>> capability implements a serial gadget with hardware and firmware,
>> and provides an interface similar with xHCI host for submitting
>> and reaping the transfer requests.
>>
>> In order to make better use of u_serial when implementing xHCI
>> debug capability in xHCI driver, this patch moves u_serial.c
>> from gadget/function to usb/common, and moves u_serial.h from
>> gadget/function to include/linux/usb.
>>
>> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> NAK, u_serial uses the gadget API. It's definitely not COMMON.
>
Okay. It seems that I can't use u_serial anyway. I will implement
a new tty glue for my case.
Best regards,
Lu Baolu
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common
2017-08-08 1:25 ` Lu Baolu
@ 2017-08-08 6:14 ` Felipe Balbi
2017-08-09 2:37 ` Lu Baolu
0 siblings, 1 reply; 9+ messages in thread
From: Felipe Balbi @ 2017-08-08 6:14 UTC (permalink / raw)
To: Lu Baolu, Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel
Hi,
Lu Baolu <baolu.lu@linux.intel.com> writes:
>> Lu Baolu <baolu.lu@linux.intel.com> writes:
>>> The component u_serial provides a glue layer between TTY layer
>>> and a USB gadget device needed to provide a basic serial port
>>> functionality. Currently, u_serial sits under gadget/function
>>> and depends on CONFIG_USB_GADGET to be compiled and used.
>>>
>>> Most of the serial gadget devices are based on a UDC (USB device
>>> controller) and implemented by making use of the Linux gadget
>>> frameworks. But we are facing other implementions as well. One
>>> example can be found with xHCI debug capability. The xHCI debug
>>> capability implements a serial gadget with hardware and firmware,
>>> and provides an interface similar with xHCI host for submitting
>>> and reaping the transfer requests.
>>>
>>> In order to make better use of u_serial when implementing xHCI
>>> debug capability in xHCI driver, this patch moves u_serial.c
>>> from gadget/function to usb/common, and moves u_serial.h from
>>> gadget/function to include/linux/usb.
>>>
>>> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
>> NAK, u_serial uses the gadget API. It's definitely not COMMON.
>>
>
> Okay. It seems that I can't use u_serial anyway. I will implement
> a new tty glue for my case.
have you looked at drivers/usb/serial/?
--
balbi
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common
2017-08-08 6:14 ` Felipe Balbi
@ 2017-08-09 2:37 ` Lu Baolu
0 siblings, 0 replies; 9+ messages in thread
From: Lu Baolu @ 2017-08-09 2:37 UTC (permalink / raw)
To: Felipe Balbi, Mathias Nyman, Greg Kroah-Hartman; +Cc: linux-usb, linux-kernel
Hi,
On 08/08/2017 02:14 PM, Felipe Balbi wrote:
> Hi,
>
> Lu Baolu <baolu.lu@linux.intel.com> writes:
>>> Lu Baolu <baolu.lu@linux.intel.com> writes:
>>>> The component u_serial provides a glue layer between TTY layer
>>>> and a USB gadget device needed to provide a basic serial port
>>>> functionality. Currently, u_serial sits under gadget/function
>>>> and depends on CONFIG_USB_GADGET to be compiled and used.
>>>>
>>>> Most of the serial gadget devices are based on a UDC (USB device
>>>> controller) and implemented by making use of the Linux gadget
>>>> frameworks. But we are facing other implementions as well. One
>>>> example can be found with xHCI debug capability. The xHCI debug
>>>> capability implements a serial gadget with hardware and firmware,
>>>> and provides an interface similar with xHCI host for submitting
>>>> and reaping the transfer requests.
>>>>
>>>> In order to make better use of u_serial when implementing xHCI
>>>> debug capability in xHCI driver, this patch moves u_serial.c
>>>> from gadget/function to usb/common, and moves u_serial.h from
>>>> gadget/function to include/linux/usb.
>>>>
>>>> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
>>> NAK, u_serial uses the gadget API. It's definitely not COMMON.
>>>
>> Okay. It seems that I can't use u_serial anyway. I will implement
>> a new tty glue for my case.
> have you looked at drivers/usb/serial/?
>
Yes, I've checked that. I think usb-serial framework is too complex
for this case. XHCI debug capability is a simple gadget attached to
xHCI host.
Best regards,
Lu Baolu
^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2017-08-09 2:37 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-08-07 8:07 [PATCH v2 0/4] usb: xhci: Add debug capability support in xhci Lu Baolu
2017-08-07 8:07 ` [PATCH v2 1/4] usb: xhci: Make some static functions global Lu Baolu
2017-08-07 8:07 ` [PATCH v2 2/4] usb: common: Move u_serial from gadget/function to usb/common Lu Baolu
2017-08-07 8:13 ` Felipe Balbi
2017-08-08 1:25 ` Lu Baolu
2017-08-08 6:14 ` Felipe Balbi
2017-08-09 2:37 ` Lu Baolu
2017-08-07 8:07 ` [PATCH v2 3/4] usb: xhci: Add DbC support in xHCI driver Lu Baolu
2017-08-07 8:07 ` [PATCH v2 4/4] usb: doc: Update document for USB3 debug port usage Lu Baolu
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