* [PATCH v4 1/5] tty_port: Add port client functions
2017-02-02 19:48 [PATCH v4 0/5] Serial slave device bus Rob Herring
@ 2017-02-02 19:48 ` Rob Herring
2017-02-02 19:48 ` [PATCH v4 2/5] dt/bindings: Add a serial/UART attached device binding Rob Herring
` (3 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Rob Herring @ 2017-02-02 19:48 UTC (permalink / raw)
To: Greg Kroah-Hartman, Marcel Holtmann, Jiri Slaby,
Sebastian Reichel, Arnd Bergmann, Dr . H . Nikolaus Schaller,
Peter Hurley, Andy Shevchenko, Alan Cox
Cc: Loic Poulain, Pavel Machek, NeilBrown, Linus Walleij,
linux-bluetooth, linux-serial, linux-kernel
Introduce a client (upward direction) operations struct for tty_port
clients. Initially supported operations are for receiving data and write
wake-up. This will allow for having clients other than an ldisc.
Convert the calls to the ldisc to use the client ops as the default
operations.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-By: Sebastian Reichel <sre@kernel.org>
Tested-By: Sebastian Reichel <sre@kernel.org>
---
v4:
- no change
v3:
- Restructured wakeup handling. We need to maintain the behavior of getting
the tty ptr only once, otherwise the serial port can get in a bad state
and stops responding.
v2:
- no change
drivers/tty/tty_buffer.c | 17 +++--------------
drivers/tty/tty_port.c | 46 ++++++++++++++++++++++++++++++++++++++++------
include/linux/tty.h | 9 ++++++++-
3 files changed, 51 insertions(+), 21 deletions(-)
diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index f4dc3e296dd5..4e7a4e9dcf4d 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -437,7 +437,7 @@ int tty_ldisc_receive_buf(struct tty_ldisc *ld, const unsigned char *p,
EXPORT_SYMBOL_GPL(tty_ldisc_receive_buf);
static int
-receive_buf(struct tty_ldisc *ld, struct tty_buffer *head, int count)
+receive_buf(struct tty_port *port, struct tty_buffer *head, int count)
{
unsigned char *p = char_buf_ptr(head, head->read);
char *f = NULL;
@@ -445,7 +445,7 @@ receive_buf(struct tty_ldisc *ld, struct tty_buffer *head, int count)
if (~head->flags & TTYB_NORMAL)
f = flag_buf_ptr(head, head->read);
- return tty_ldisc_receive_buf(ld, p, f, count);
+ return port->client_ops->receive_buf(port, p, f, count);
}
/**
@@ -465,16 +465,6 @@ static void flush_to_ldisc(struct work_struct *work)
{
struct tty_port *port = container_of(work, struct tty_port, buf.work);
struct tty_bufhead *buf = &port->buf;
- struct tty_struct *tty;
- struct tty_ldisc *disc;
-
- tty = READ_ONCE(port->itty);
- if (tty == NULL)
- return;
-
- disc = tty_ldisc_ref(tty);
- if (disc == NULL)
- return;
mutex_lock(&buf->lock);
@@ -504,7 +494,7 @@ static void flush_to_ldisc(struct work_struct *work)
continue;
}
- count = receive_buf(disc, head, count);
+ count = receive_buf(port, head, count);
if (!count)
break;
head->read += count;
@@ -512,7 +502,6 @@ static void flush_to_ldisc(struct work_struct *work)
mutex_unlock(&buf->lock);
- tty_ldisc_deref(disc);
}
/**
diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 1d8804843103..8d9886b06037 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -17,6 +17,44 @@
#include <linux/delay.h>
#include <linux/module.h>
+static int tty_port_default_receive_buf(struct tty_port *port,
+ const unsigned char *p,
+ const unsigned char *f, size_t count)
+{
+ int ret;
+ struct tty_struct *tty;
+ struct tty_ldisc *disc;
+
+ tty = READ_ONCE(port->itty);
+ if (!tty)
+ return 0;
+
+ disc = tty_ldisc_ref(tty);
+ if (!disc)
+ return 0;
+
+ ret = tty_ldisc_receive_buf(disc, p, (char *)f, count);
+
+ tty_ldisc_deref(disc);
+
+ return ret;
+}
+
+static void tty_port_default_wakeup(struct tty_port *port)
+{
+ struct tty_struct *tty = tty_port_tty_get(port);
+
+ if (tty) {
+ tty_wakeup(tty);
+ tty_kref_put(tty);
+ }
+}
+
+static const struct tty_port_client_operations default_client_ops = {
+ .receive_buf = tty_port_default_receive_buf,
+ .write_wakeup = tty_port_default_wakeup,
+};
+
void tty_port_init(struct tty_port *port)
{
memset(port, 0, sizeof(*port));
@@ -28,6 +66,7 @@ void tty_port_init(struct tty_port *port)
spin_lock_init(&port->lock);
port->close_delay = (50 * HZ) / 100;
port->closing_wait = (3000 * HZ) / 100;
+ port->client_ops = &default_client_ops;
kref_init(&port->kref);
}
EXPORT_SYMBOL(tty_port_init);
@@ -272,12 +311,7 @@ EXPORT_SYMBOL_GPL(tty_port_tty_hangup);
*/
void tty_port_tty_wakeup(struct tty_port *port)
{
- struct tty_struct *tty = tty_port_tty_get(port);
-
- if (tty) {
- tty_wakeup(tty);
- tty_kref_put(tty);
- }
+ port->client_ops->write_wakeup(port);
}
EXPORT_SYMBOL_GPL(tty_port_tty_wakeup);
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 21c0fabfed60..1017e904c0a3 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -217,12 +217,18 @@ struct tty_port_operations {
/* Called on the final put of a port */
void (*destruct)(struct tty_port *port);
};
-
+
+struct tty_port_client_operations {
+ int (*receive_buf)(struct tty_port *port, const unsigned char *, const unsigned char *, size_t);
+ void (*write_wakeup)(struct tty_port *port);
+};
+
struct tty_port {
struct tty_bufhead buf; /* Locked internally */
struct tty_struct *tty; /* Back pointer */
struct tty_struct *itty; /* internal back ptr */
const struct tty_port_operations *ops; /* Port operations */
+ const struct tty_port_client_operations *client_ops; /* Port client operations */
spinlock_t lock; /* Lock protecting tty field */
int blocked_open; /* Waiting to open */
int count; /* Usage count */
@@ -241,6 +247,7 @@ struct tty_port {
based drain is needed else
set to size of fifo */
struct kref kref; /* Ref counter */
+ void *client_data;
};
/* tty_port::iflags bits -- use atomic bit ops */
--
2.10.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v4 2/5] dt/bindings: Add a serial/UART attached device binding
2017-02-02 19:48 [PATCH v4 0/5] Serial slave device bus Rob Herring
2017-02-02 19:48 ` [PATCH v4 1/5] tty_port: Add port client functions Rob Herring
@ 2017-02-02 19:48 ` Rob Herring
2017-02-02 19:48 ` [PATCH v4 3/5] serdev: Introduce new bus for serial attached devices Rob Herring
` (2 subsequent siblings)
4 siblings, 0 replies; 6+ messages in thread
From: Rob Herring @ 2017-02-02 19:48 UTC (permalink / raw)
To: Greg Kroah-Hartman, Marcel Holtmann, Jiri Slaby,
Sebastian Reichel, Arnd Bergmann, Dr . H . Nikolaus Schaller,
Peter Hurley, Andy Shevchenko, Alan Cox
Cc: Loic Poulain, Pavel Machek, NeilBrown, Linus Walleij,
linux-bluetooth, linux-serial, linux-kernel
Add a common binding for describing serial/UART attached devices. Common
examples are Bluetooth, WiFi, NFC and GPS devices.
Serial attached devices are represented as child nodes of a UART node.
This may need to be extended for more complex devices with multiple
interfaces, but for the simple cases a child node is sufficient.
Tested-By: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Rob Herring <robh@kernel.org>
---
v4:
- no change
v3:
- no change
v2:
- Drop reg property
- Add max-speed property
.../devicetree/bindings/serial/slave-device.txt | 36 ++++++++++++++++++++++
1 file changed, 36 insertions(+)
create mode 100644 Documentation/devicetree/bindings/serial/slave-device.txt
diff --git a/Documentation/devicetree/bindings/serial/slave-device.txt b/Documentation/devicetree/bindings/serial/slave-device.txt
new file mode 100644
index 000000000000..f66037928f5f
--- /dev/null
+++ b/Documentation/devicetree/bindings/serial/slave-device.txt
@@ -0,0 +1,36 @@
+Serial Slave Device DT binding
+
+This documents the binding structure and common properties for serial
+attached devices. Common examples include Bluetooth, WiFi, NFC and GPS
+devices.
+
+Serial attached devices shall be a child node of the host UART device the
+slave device is attached to. It is expected that the attached device is
+the only child node of the UART device. The slave device node name shall
+reflect the generic type of device for the node.
+
+Required Properties:
+
+- compatible : A string reflecting the vendor and specific device the node
+ represents.
+
+Optional Properties:
+
+- max-speed : The maximum baud rate the device operates at. This should
+ only be present if the maximum is less than the slave device
+ can support. For example, a particular board has some signal
+ quality issue or the host processor can't support higher
+ baud rates.
+
+Example:
+
+serial@1234 {
+ compatible = "ns16550a";
+ interrupts = <1>;
+
+ bluetooth {
+ compatible = "brcm,bcm43341-bt";
+ interrupt-parent = <&gpio>;
+ interrupts = <10>;
+ };
+};
--
2.10.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v4 3/5] serdev: Introduce new bus for serial attached devices
2017-02-02 19:48 [PATCH v4 0/5] Serial slave device bus Rob Herring
2017-02-02 19:48 ` [PATCH v4 1/5] tty_port: Add port client functions Rob Herring
2017-02-02 19:48 ` [PATCH v4 2/5] dt/bindings: Add a serial/UART attached device binding Rob Herring
@ 2017-02-02 19:48 ` Rob Herring
2017-02-02 19:48 ` [PATCH v4 4/5] serdev: add a tty port controller driver Rob Herring
2017-02-02 19:48 ` [PATCH v4 5/5] tty_port: register tty ports with serdev bus Rob Herring
4 siblings, 0 replies; 6+ messages in thread
From: Rob Herring @ 2017-02-02 19:48 UTC (permalink / raw)
To: Greg Kroah-Hartman, Marcel Holtmann, Jiri Slaby,
Sebastian Reichel, Arnd Bergmann, Dr . H . Nikolaus Schaller,
Peter Hurley, Andy Shevchenko, Alan Cox
Cc: Loic Poulain, Pavel Machek, NeilBrown, Linus Walleij,
linux-bluetooth, linux-serial, linux-kernel
The serdev bus is designed for devices such as Bluetooth, WiFi, GPS
and NFC connected to UARTs on host processors. Tradionally these have
been handled with tty line disciplines, rfkill, and userspace glue such
as hciattach. This approach has many drawbacks since it doesn't fit
into the Linux driver model. Handling of sideband signals, power control
and firmware loading are the main issues.
This creates a serdev bus with controllers (i.e. host serial ports) and
attached devices. Typically, these are point to point connections, but
some devices have muxing protocols or a h/w mux is conceivable. Any
muxing is not yet supported with the serdev bus.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-By: Sebastian Reichel <sre@kernel.org>
Tested-By: Sebastian Reichel <sre@kernel.org>
---
v4:
- Use IS_ENABLED() in serdev.h to fix module builds
v3:
- Added empty device functions for !CONFIG_SERIAL_DEV_BUS
v2:
- Change the sysfs visible names to "serial". Kept serdev as kernel
internal name.
- Make function ptr checks and calls follow a consistent structure
- Return error if controller .open() is missing
- Sort includes
- Add an ACPI TODO note
- Fix serdev_controller_add error path handling
- Fix DT child device adding error handling
- Add modalias sysfs attr and uevent hook
- Fix module email address
MAINTAINERS | 8 +
drivers/char/Kconfig | 1 +
drivers/tty/Makefile | 1 +
drivers/tty/serdev/Kconfig | 8 +
drivers/tty/serdev/Makefile | 3 +
drivers/tty/serdev/core.c | 421 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/serdev.h | 241 +++++++++++++++++++++++++
7 files changed, 683 insertions(+)
create mode 100644 drivers/tty/serdev/Kconfig
create mode 100644 drivers/tty/serdev/Makefile
create mode 100644 drivers/tty/serdev/core.c
create mode 100644 include/linux/serdev.h
diff --git a/MAINTAINERS b/MAINTAINERS
index c36976d3bd1a..90db2b5d418c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -10831,6 +10831,14 @@ S: Maintained
F: Documentation/devicetree/bindings/serial/
F: drivers/tty/serial/
+SERIAL DEVICE BUS
+M: Rob Herring <robh@kernel.org>
+L: linux-serial@vger.kernel.org
+S: Maintained
+F: Documentation/devicetree/bindings/serial/slave-device.txt
+F: drivers/tty/serdev/
+F: include/linux/serdev.h
+
SERIAL IR RECEIVER
M: Sean Young <sean@mess.org>
L: linux-media@vger.kernel.org
diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index fde005ef9d36..db8f74bbaf3e 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -46,6 +46,7 @@ config SGI_MBCS
say Y or M here, otherwise say N.
source "drivers/tty/serial/Kconfig"
+source "drivers/tty/serdev/Kconfig"
config TTY_PRINTK
tristate "TTY driver to output user messages via printk"
diff --git a/drivers/tty/Makefile b/drivers/tty/Makefile
index 5817e2397463..b95bed92da9f 100644
--- a/drivers/tty/Makefile
+++ b/drivers/tty/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_R3964) += n_r3964.o
obj-y += vt/
obj-$(CONFIG_HVC_DRIVER) += hvc/
obj-y += serial/
+obj-$(CONFIG_SERIAL_DEV_BUS) += serdev/
# tty drivers
obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o
diff --git a/drivers/tty/serdev/Kconfig b/drivers/tty/serdev/Kconfig
new file mode 100644
index 000000000000..3b6ecd187bef
--- /dev/null
+++ b/drivers/tty/serdev/Kconfig
@@ -0,0 +1,8 @@
+#
+# Serial bus device driver configuration
+#
+menuconfig SERIAL_DEV_BUS
+ tristate "Serial device bus"
+ help
+ Core support for devices connected via a serial port.
+
diff --git a/drivers/tty/serdev/Makefile b/drivers/tty/serdev/Makefile
new file mode 100644
index 000000000000..01a9b62183f4
--- /dev/null
+++ b/drivers/tty/serdev/Makefile
@@ -0,0 +1,3 @@
+serdev-objs := core.o
+
+obj-$(CONFIG_SERIAL_DEV_BUS) += serdev.o
diff --git a/drivers/tty/serdev/core.c b/drivers/tty/serdev/core.c
new file mode 100644
index 000000000000..f4c6c90add78
--- /dev/null
+++ b/drivers/tty/serdev/core.c
@@ -0,0 +1,421 @@
+/*
+ * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
+ *
+ * Based on drivers/spmi/spmi.c:
+ * Copyright (c) 2012-2015, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/errno.h>
+#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/serdev.h>
+#include <linux/slab.h>
+
+static bool is_registered;
+static DEFINE_IDA(ctrl_ida);
+
+static void serdev_device_release(struct device *dev)
+{
+ struct serdev_device *serdev = to_serdev_device(dev);
+ kfree(serdev);
+}
+
+static const struct device_type serdev_device_type = {
+ .release = serdev_device_release,
+};
+
+static void serdev_ctrl_release(struct device *dev)
+{
+ struct serdev_controller *ctrl = to_serdev_controller(dev);
+ ida_simple_remove(&ctrl_ida, ctrl->nr);
+ kfree(ctrl);
+}
+
+static const struct device_type serdev_ctrl_type = {
+ .release = serdev_ctrl_release,
+};
+
+static int serdev_device_match(struct device *dev, struct device_driver *drv)
+{
+ /* TODO: ACPI and platform matching */
+ return of_driver_match_device(dev, drv);
+}
+
+static int serdev_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ /* TODO: ACPI and platform modalias */
+ return of_device_uevent_modalias(dev, env);
+}
+
+/**
+ * serdev_device_add() - add a device previously constructed via serdev_device_alloc()
+ * @serdev: serdev_device to be added
+ */
+int serdev_device_add(struct serdev_device *serdev)
+{
+ struct device *parent = serdev->dev.parent;
+ int err;
+
+ dev_set_name(&serdev->dev, "%s-%d", dev_name(parent), serdev->nr);
+
+ err = device_add(&serdev->dev);
+ if (err < 0) {
+ dev_err(&serdev->dev, "Can't add %s, status %d\n",
+ dev_name(&serdev->dev), err);
+ goto err_device_add;
+ }
+
+ dev_dbg(&serdev->dev, "device %s registered\n", dev_name(&serdev->dev));
+
+err_device_add:
+ return err;
+}
+EXPORT_SYMBOL_GPL(serdev_device_add);
+
+/**
+ * serdev_device_remove(): remove an serdev device
+ * @serdev: serdev_device to be removed
+ */
+void serdev_device_remove(struct serdev_device *serdev)
+{
+ device_unregister(&serdev->dev);
+}
+EXPORT_SYMBOL_GPL(serdev_device_remove);
+
+int serdev_device_open(struct serdev_device *serdev)
+{
+ struct serdev_controller *ctrl = serdev->ctrl;
+
+ if (!ctrl || !ctrl->ops->open)
+ return -EINVAL;
+
+ return ctrl->ops->open(ctrl);
+}
+EXPORT_SYMBOL_GPL(serdev_device_open);
+
+void serdev_device_close(struct serdev_device *serdev)
+{
+ struct serdev_controller *ctrl = serdev->ctrl;
+
+ if (!ctrl || !ctrl->ops->close)
+ return;
+
+ ctrl->ops->close(ctrl);
+}
+EXPORT_SYMBOL_GPL(serdev_device_close);
+
+int serdev_device_write_buf(struct serdev_device *serdev,
+ const unsigned char *buf, size_t count)
+{
+ struct serdev_controller *ctrl = serdev->ctrl;
+
+ if (!ctrl || !ctrl->ops->write_buf)
+ return -EINVAL;
+
+ return ctrl->ops->write_buf(ctrl, buf, count);
+}
+EXPORT_SYMBOL_GPL(serdev_device_write_buf);
+
+void serdev_device_write_flush(struct serdev_device *serdev)
+{
+ struct serdev_controller *ctrl = serdev->ctrl;
+
+ if (!ctrl || !ctrl->ops->write_flush)
+ return;
+
+ ctrl->ops->write_flush(ctrl);
+}
+EXPORT_SYMBOL_GPL(serdev_device_write_flush);
+
+int serdev_device_write_room(struct serdev_device *serdev)
+{
+ struct serdev_controller *ctrl = serdev->ctrl;
+
+ if (!ctrl || !ctrl->ops->write_room)
+ return 0;
+
+ return serdev->ctrl->ops->write_room(ctrl);
+}
+EXPORT_SYMBOL_GPL(serdev_device_write_room);
+
+unsigned int serdev_device_set_baudrate(struct serdev_device *serdev, unsigned int speed)
+{
+ struct serdev_controller *ctrl = serdev->ctrl;
+
+ if (!ctrl || !ctrl->ops->set_baudrate)
+ return 0;
+
+ return ctrl->ops->set_baudrate(ctrl, speed);
+
+}
+EXPORT_SYMBOL_GPL(serdev_device_set_baudrate);
+
+void serdev_device_set_flow_control(struct serdev_device *serdev, bool enable)
+{
+ struct serdev_controller *ctrl = serdev->ctrl;
+
+ if (!ctrl || !ctrl->ops->set_flow_control)
+ return;
+
+ ctrl->ops->set_flow_control(ctrl, enable);
+}
+EXPORT_SYMBOL_GPL(serdev_device_set_flow_control);
+
+static int serdev_drv_probe(struct device *dev)
+{
+ const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
+
+ return sdrv->probe(to_serdev_device(dev));
+}
+
+static int serdev_drv_remove(struct device *dev)
+{
+ const struct serdev_device_driver *sdrv = to_serdev_device_driver(dev->driver);
+
+ sdrv->remove(to_serdev_device(dev));
+ return 0;
+}
+
+static ssize_t modalias_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ ssize_t len = of_device_get_modalias(dev, buf, PAGE_SIZE - 2);
+ buf[len] = '\n';
+ buf[len+1] = 0;
+ return len+1;
+}
+
+static struct device_attribute serdev_device_attrs[] = {
+ __ATTR_RO(modalias),
+ __ATTR_NULL
+};
+
+static struct bus_type serdev_bus_type = {
+ .name = "serial",
+ .match = serdev_device_match,
+ .probe = serdev_drv_probe,
+ .remove = serdev_drv_remove,
+ .uevent = serdev_uevent,
+ .dev_attrs = serdev_device_attrs,
+};
+
+/**
+ * serdev_controller_alloc() - Allocate a new serdev device
+ * @ctrl: associated controller
+ *
+ * Caller is responsible for either calling serdev_device_add() to add the
+ * newly allocated controller, or calling serdev_device_put() to discard it.
+ */
+struct serdev_device *serdev_device_alloc(struct serdev_controller *ctrl)
+{
+ struct serdev_device *serdev;
+
+ serdev = kzalloc(sizeof(*serdev), GFP_KERNEL);
+ if (!serdev)
+ return NULL;
+
+ serdev->ctrl = ctrl;
+ ctrl->serdev = serdev;
+ device_initialize(&serdev->dev);
+ serdev->dev.parent = &ctrl->dev;
+ serdev->dev.bus = &serdev_bus_type;
+ serdev->dev.type = &serdev_device_type;
+ return serdev;
+}
+EXPORT_SYMBOL_GPL(serdev_device_alloc);
+
+/**
+ * serdev_controller_alloc() - Allocate a new serdev controller
+ * @parent: parent device
+ * @size: size of private data
+ *
+ * Caller is responsible for either calling serdev_controller_add() to add the
+ * newly allocated controller, or calling serdev_controller_put() to discard it.
+ * The allocated private data region may be accessed via
+ * serdev_controller_get_drvdata()
+ */
+struct serdev_controller *serdev_controller_alloc(struct device *parent,
+ size_t size)
+{
+ struct serdev_controller *ctrl;
+ int id;
+
+ if (WARN_ON(!parent))
+ return NULL;
+
+ ctrl = kzalloc(sizeof(*ctrl) + size, GFP_KERNEL);
+ if (!ctrl)
+ return NULL;
+
+ device_initialize(&ctrl->dev);
+ ctrl->dev.type = &serdev_ctrl_type;
+ ctrl->dev.bus = &serdev_bus_type;
+ ctrl->dev.parent = parent;
+ ctrl->dev.of_node = parent->of_node;
+ serdev_controller_set_drvdata(ctrl, &ctrl[1]);
+
+ id = ida_simple_get(&ctrl_ida, 0, 0, GFP_KERNEL);
+ if (id < 0) {
+ dev_err(parent,
+ "unable to allocate serdev controller identifier.\n");
+ serdev_controller_put(ctrl);
+ return NULL;
+ }
+
+ ctrl->nr = id;
+ dev_set_name(&ctrl->dev, "serial%d", id);
+
+ dev_dbg(&ctrl->dev, "allocated controller 0x%p id %d\n", ctrl, id);
+ return ctrl;
+}
+EXPORT_SYMBOL_GPL(serdev_controller_alloc);
+
+static int of_serdev_register_devices(struct serdev_controller *ctrl)
+{
+ struct device_node *node;
+ struct serdev_device *serdev = NULL;
+ int err;
+ bool found = false;
+
+ for_each_available_child_of_node(ctrl->dev.of_node, node) {
+ if (!of_get_property(node, "compatible", NULL))
+ continue;
+
+ dev_dbg(&ctrl->dev, "adding child %s\n", node->full_name);
+
+ serdev = serdev_device_alloc(ctrl);
+ if (!serdev)
+ continue;
+
+ serdev->dev.of_node = node;
+
+ err = serdev_device_add(serdev);
+ if (err) {
+ dev_err(&serdev->dev,
+ "failure adding device. status %d\n", err);
+ serdev_device_put(serdev);
+ } else
+ found = true;
+ }
+ if (!found)
+ return -ENODEV;
+
+ return 0;
+}
+
+/**
+ * serdev_controller_add() - Add an serdev controller
+ * @ctrl: controller to be registered.
+ *
+ * Register a controller previously allocated via serdev_controller_alloc() with
+ * the serdev core.
+ */
+int serdev_controller_add(struct serdev_controller *ctrl)
+{
+ int ret;
+
+ /* Can't register until after driver model init */
+ if (WARN_ON(!is_registered))
+ return -EAGAIN;
+
+ ret = device_add(&ctrl->dev);
+ if (ret)
+ return ret;
+
+ ret = of_serdev_register_devices(ctrl);
+ if (ret)
+ goto out_dev_del;
+
+ dev_dbg(&ctrl->dev, "serdev%d registered: dev:%p\n",
+ ctrl->nr, &ctrl->dev);
+ return 0;
+
+out_dev_del:
+ device_del(&ctrl->dev);
+ return ret;
+};
+EXPORT_SYMBOL_GPL(serdev_controller_add);
+
+/* Remove a device associated with a controller */
+static int serdev_remove_device(struct device *dev, void *data)
+{
+ struct serdev_device *serdev = to_serdev_device(dev);
+ if (dev->type == &serdev_device_type)
+ serdev_device_remove(serdev);
+ return 0;
+}
+
+/**
+ * serdev_controller_remove(): remove an serdev controller
+ * @ctrl: controller to remove
+ *
+ * Remove a serdev controller. Caller is responsible for calling
+ * serdev_controller_put() to discard the allocated controller.
+ */
+void serdev_controller_remove(struct serdev_controller *ctrl)
+{
+ int dummy;
+
+ if (!ctrl)
+ return;
+
+ dummy = device_for_each_child(&ctrl->dev, NULL,
+ serdev_remove_device);
+ device_del(&ctrl->dev);
+}
+EXPORT_SYMBOL_GPL(serdev_controller_remove);
+
+/**
+ * serdev_driver_register() - Register client driver with serdev core
+ * @sdrv: client driver to be associated with client-device.
+ *
+ * This API will register the client driver with the serdev framework.
+ * It is typically called from the driver's module-init function.
+ */
+int __serdev_device_driver_register(struct serdev_device_driver *sdrv, struct module *owner)
+{
+ sdrv->driver.bus = &serdev_bus_type;
+ sdrv->driver.owner = owner;
+
+ /* force drivers to async probe so I/O is possible in probe */
+ sdrv->driver.probe_type = PROBE_PREFER_ASYNCHRONOUS;
+
+ return driver_register(&sdrv->driver);
+}
+EXPORT_SYMBOL_GPL(__serdev_device_driver_register);
+
+static void __exit serdev_exit(void)
+{
+ bus_unregister(&serdev_bus_type);
+}
+module_exit(serdev_exit);
+
+static int __init serdev_init(void)
+{
+ int ret;
+
+ ret = bus_register(&serdev_bus_type);
+ if (ret)
+ return ret;
+
+ is_registered = true;
+ return 0;
+}
+/* Must be before serial drivers register */
+postcore_initcall(serdev_init);
+
+MODULE_AUTHOR("Rob Herring <robh@kernel.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Serial attached device bus");
diff --git a/include/linux/serdev.h b/include/linux/serdev.h
new file mode 100644
index 000000000000..3ac26c1a8aab
--- /dev/null
+++ b/include/linux/serdev.h
@@ -0,0 +1,241 @@
+/*
+ * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#ifndef _LINUX_SERDEV_H
+#define _LINUX_SERDEV_H
+
+#include <linux/types.h>
+#include <linux/device.h>
+
+struct serdev_controller;
+struct serdev_device;
+
+/*
+ * serdev device structures
+ */
+
+/**
+ * struct serdev_device_ops - Callback operations for a serdev device
+ * @receive_buf: Function called with data received from device.
+ * @write_wakeup: Function called when ready to transmit more data.
+ */
+struct serdev_device_ops {
+ int (*receive_buf)(struct serdev_device *, const unsigned char *, size_t);
+ void (*write_wakeup)(struct serdev_device *);
+};
+
+/**
+ * struct serdev_device - Basic representation of an serdev device
+ * @dev: Driver model representation of the device.
+ * @nr: Device number on serdev bus.
+ * @ctrl: serdev controller managing this device.
+ * @ops: Device operations.
+ */
+struct serdev_device {
+ struct device dev;
+ int nr;
+ struct serdev_controller *ctrl;
+ const struct serdev_device_ops *ops;
+};
+
+static inline struct serdev_device *to_serdev_device(struct device *d)
+{
+ return container_of(d, struct serdev_device, dev);
+}
+
+/**
+ * struct serdev_device_driver - serdev slave device driver
+ * @driver: serdev device drivers should initialize name field of this
+ * structure.
+ * @probe: binds this driver to a serdev device.
+ * @remove: unbinds this driver from the serdev device.
+ */
+struct serdev_device_driver {
+ struct device_driver driver;
+ int (*probe)(struct serdev_device *);
+ void (*remove)(struct serdev_device *);
+};
+
+static inline struct serdev_device_driver *to_serdev_device_driver(struct device_driver *d)
+{
+ return container_of(d, struct serdev_device_driver, driver);
+}
+
+/*
+ * serdev controller structures
+ */
+struct serdev_controller_ops {
+ int (*write_buf)(struct serdev_controller *, const unsigned char *, size_t);
+ void (*write_flush)(struct serdev_controller *);
+ int (*write_room)(struct serdev_controller *);
+ int (*open)(struct serdev_controller *);
+ void (*close)(struct serdev_controller *);
+ void (*set_flow_control)(struct serdev_controller *, bool);
+ unsigned int (*set_baudrate)(struct serdev_controller *, unsigned int);
+};
+
+/**
+ * struct serdev_controller - interface to the serdev controller
+ * @dev: Driver model representation of the device.
+ * @nr: number identifier for this controller/bus.
+ * @serdev: Pointer to slave device for this controller.
+ * @ops: Controller operations.
+ */
+struct serdev_controller {
+ struct device dev;
+ unsigned int nr;
+ struct serdev_device *serdev;
+ const struct serdev_controller_ops *ops;
+};
+
+static inline struct serdev_controller *to_serdev_controller(struct device *d)
+{
+ return container_of(d, struct serdev_controller, dev);
+}
+
+static inline void *serdev_device_get_drvdata(const struct serdev_device *serdev)
+{
+ return dev_get_drvdata(&serdev->dev);
+}
+
+static inline void serdev_device_set_drvdata(struct serdev_device *serdev, void *data)
+{
+ dev_set_drvdata(&serdev->dev, data);
+}
+
+/**
+ * serdev_device_put() - decrement serdev device refcount
+ * @serdev serdev device.
+ */
+static inline void serdev_device_put(struct serdev_device *serdev)
+{
+ if (serdev)
+ put_device(&serdev->dev);
+}
+
+static inline void serdev_device_set_client_ops(struct serdev_device *serdev,
+ const struct serdev_device_ops *ops)
+{
+ serdev->ops = ops;
+}
+
+static inline
+void *serdev_controller_get_drvdata(const struct serdev_controller *ctrl)
+{
+ return ctrl ? dev_get_drvdata(&ctrl->dev) : NULL;
+}
+
+static inline void serdev_controller_set_drvdata(struct serdev_controller *ctrl,
+ void *data)
+{
+ dev_set_drvdata(&ctrl->dev, data);
+}
+
+/**
+ * serdev_controller_put() - decrement controller refcount
+ * @ctrl serdev controller.
+ */
+static inline void serdev_controller_put(struct serdev_controller *ctrl)
+{
+ if (ctrl)
+ put_device(&ctrl->dev);
+}
+
+struct serdev_device *serdev_device_alloc(struct serdev_controller *);
+int serdev_device_add(struct serdev_device *);
+void serdev_device_remove(struct serdev_device *);
+
+struct serdev_controller *serdev_controller_alloc(struct device *, size_t);
+int serdev_controller_add(struct serdev_controller *);
+void serdev_controller_remove(struct serdev_controller *);
+
+static inline void serdev_controller_write_wakeup(struct serdev_controller *ctrl)
+{
+ struct serdev_device *serdev = ctrl->serdev;
+
+ if (!serdev || !serdev->ops->write_wakeup)
+ return;
+
+ serdev->ops->write_wakeup(ctrl->serdev);
+}
+
+static inline int serdev_controller_receive_buf(struct serdev_controller *ctrl,
+ const unsigned char *data,
+ size_t count)
+{
+ struct serdev_device *serdev = ctrl->serdev;
+
+ if (!serdev || !serdev->ops->receive_buf)
+ return -EINVAL;
+
+ return serdev->ops->receive_buf(ctrl->serdev, data, count);
+}
+
+#if IS_ENABLED(CONFIG_SERIAL_DEV_BUS)
+
+int serdev_device_open(struct serdev_device *);
+void serdev_device_close(struct serdev_device *);
+unsigned int serdev_device_set_baudrate(struct serdev_device *, unsigned int);
+void serdev_device_set_flow_control(struct serdev_device *, bool);
+int serdev_device_write_buf(struct serdev_device *, const unsigned char *, size_t);
+void serdev_device_write_flush(struct serdev_device *);
+int serdev_device_write_room(struct serdev_device *);
+
+/*
+ * serdev device driver functions
+ */
+int __serdev_device_driver_register(struct serdev_device_driver *, struct module *);
+#define serdev_device_driver_register(sdrv) \
+ __serdev_device_driver_register(sdrv, THIS_MODULE)
+
+/**
+ * serdev_device_driver_unregister() - unregister an serdev client driver
+ * @sdrv: the driver to unregister
+ */
+static inline void serdev_device_driver_unregister(struct serdev_device_driver *sdrv)
+{
+ if (sdrv)
+ driver_unregister(&sdrv->driver);
+}
+
+#define module_serdev_device_driver(__serdev_device_driver) \
+ module_driver(__serdev_device_driver, serdev_device_driver_register, \
+ serdev_device_driver_unregister)
+
+#else
+
+static inline int serdev_device_open(struct serdev_device *sdev)
+{
+ return -ENODEV;
+}
+static inline void serdev_device_close(struct serdev_device *sdev) {}
+static inline unsigned int serdev_device_set_baudrate(struct serdev_device *sdev, unsigned int baudrate)
+{
+ return 0;
+}
+static inline void serdev_device_set_flow_control(struct serdev_device *sdev, bool enable) {}
+static inline int serdev_device_write_buf(struct serdev_device *sdev, const unsigned char *buf, size_t count)
+{
+ return -ENODEV;
+}
+static inline void serdev_device_write_flush(struct serdev_device *sdev) {}
+static inline int serdev_device_write_room(struct serdev_device *sdev)
+{
+ return 0;
+}
+
+#define serdev_device_driver_register(x)
+#define serdev_device_driver_unregister(x)
+
+#endif /* CONFIG_SERIAL_DEV_BUS */
+
+#endif /*_LINUX_SERDEV_H */
--
2.10.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v4 4/5] serdev: add a tty port controller driver
2017-02-02 19:48 [PATCH v4 0/5] Serial slave device bus Rob Herring
` (2 preceding siblings ...)
2017-02-02 19:48 ` [PATCH v4 3/5] serdev: Introduce new bus for serial attached devices Rob Herring
@ 2017-02-02 19:48 ` Rob Herring
2017-02-02 19:48 ` [PATCH v4 5/5] tty_port: register tty ports with serdev bus Rob Herring
4 siblings, 0 replies; 6+ messages in thread
From: Rob Herring @ 2017-02-02 19:48 UTC (permalink / raw)
To: Greg Kroah-Hartman, Marcel Holtmann, Jiri Slaby,
Sebastian Reichel, Arnd Bergmann, Dr . H . Nikolaus Schaller,
Peter Hurley, Andy Shevchenko, Alan Cox
Cc: Loic Poulain, Pavel Machek, NeilBrown, Linus Walleij,
linux-bluetooth, linux-serial, linux-kernel
Add a serdev controller driver for tty ports.
The controller is registered with serdev when tty ports are registered
with the TTY core. As the TTY core is built-in only, this has the side
effect of making serdev built-in as well.
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-By: Sebastian Reichel <sre@kernel.org>
Tested-By: Sebastian Reichel <sre@kernel.org>
---
v4:
- Remove setting of tty->receive_room. Was only necessary for old
ldisc->receive_buf() function.
v3:
- Handle testing TTY_DO_WRITE_WAKEUP in write_wakeup callback due to tty
core change in patch #1.
- Remove the mutex. The atomic bit is enough.
- Removed unused atomic bit defines.
- Made ctrl_ops static and const.
v2:
- Sort includes
- Made goto labels more descriptive
- Use tty-> instead of serdev->tty-> where possible
- Drop DT specific check in serdev_tty_port_register. DT specifics are only
in core bus code now.
- Comments on #endif's
- Use "depends on SERIAL_DEV_BUS != m" instead of "= y"
- Dropped module properties (not a module)
drivers/tty/serdev/Kconfig | 8 ++
drivers/tty/serdev/Makefile | 2 +
drivers/tty/serdev/serdev-ttyport.c | 224 ++++++++++++++++++++++++++++++++++++
include/linux/serdev.h | 21 ++++
4 files changed, 255 insertions(+)
create mode 100644 drivers/tty/serdev/serdev-ttyport.c
diff --git a/drivers/tty/serdev/Kconfig b/drivers/tty/serdev/Kconfig
index 3b6ecd187bef..cdc6b820cf93 100644
--- a/drivers/tty/serdev/Kconfig
+++ b/drivers/tty/serdev/Kconfig
@@ -6,3 +6,11 @@ menuconfig SERIAL_DEV_BUS
help
Core support for devices connected via a serial port.
+if SERIAL_DEV_BUS
+
+config SERIAL_DEV_CTRL_TTYPORT
+ bool "Serial device TTY port controller"
+ depends on TTY
+ depends on SERIAL_DEV_BUS != m
+
+endif
diff --git a/drivers/tty/serdev/Makefile b/drivers/tty/serdev/Makefile
index 01a9b62183f4..0cbdb9444d9d 100644
--- a/drivers/tty/serdev/Makefile
+++ b/drivers/tty/serdev/Makefile
@@ -1,3 +1,5 @@
serdev-objs := core.o
obj-$(CONFIG_SERIAL_DEV_BUS) += serdev.o
+
+obj-$(CONFIG_SERIAL_DEV_CTRL_TTYPORT) += serdev-ttyport.o
diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c
new file mode 100644
index 000000000000..683320b81a2b
--- /dev/null
+++ b/drivers/tty/serdev/serdev-ttyport.c
@@ -0,0 +1,224 @@
+/*
+ * Copyright (C) 2016-2017 Linaro Ltd., Rob Herring <robh@kernel.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/serdev.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+
+#define SERPORT_ACTIVE 1
+
+struct serport {
+ struct tty_port *port;
+ struct tty_struct *tty;
+ struct tty_driver *tty_drv;
+ int tty_idx;
+ unsigned long flags;
+};
+
+/*
+ * Callback functions from the tty port.
+ */
+
+static int ttyport_receive_buf(struct tty_port *port, const unsigned char *cp,
+ const unsigned char *fp, size_t count)
+{
+ struct serdev_controller *ctrl = port->client_data;
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+
+ if (!test_bit(SERPORT_ACTIVE, &serport->flags))
+ return 0;
+
+ return serdev_controller_receive_buf(ctrl, cp, count);
+}
+
+static void ttyport_write_wakeup(struct tty_port *port)
+{
+ struct serdev_controller *ctrl = port->client_data;
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+
+ if (!test_and_clear_bit(TTY_DO_WRITE_WAKEUP, &port->tty->flags))
+ return;
+
+ if (test_bit(SERPORT_ACTIVE, &serport->flags))
+ serdev_controller_write_wakeup(ctrl);
+}
+
+static const struct tty_port_client_operations client_ops = {
+ .receive_buf = ttyport_receive_buf,
+ .write_wakeup = ttyport_write_wakeup,
+};
+
+/*
+ * Callback functions from the serdev core.
+ */
+
+static int ttyport_write_buf(struct serdev_controller *ctrl, const unsigned char *data, size_t len)
+{
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+ struct tty_struct *tty = serport->tty;
+
+ if (!test_bit(SERPORT_ACTIVE, &serport->flags))
+ return 0;
+
+ set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
+ return tty->ops->write(serport->tty, data, len);
+}
+
+static void ttyport_write_flush(struct serdev_controller *ctrl)
+{
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+ struct tty_struct *tty = serport->tty;
+
+ tty_driver_flush_buffer(tty);
+}
+
+static int ttyport_write_room(struct serdev_controller *ctrl)
+{
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+ struct tty_struct *tty = serport->tty;
+
+ return tty_write_room(tty);
+}
+
+static int ttyport_open(struct serdev_controller *ctrl)
+{
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+ struct tty_struct *tty;
+ struct ktermios ktermios;
+
+ tty = tty_init_dev(serport->tty_drv, serport->tty_idx);
+ serport->tty = tty;
+
+ serport->port->client_ops = &client_ops;
+ serport->port->client_data = ctrl;
+
+ if (tty->ops->open)
+ tty->ops->open(serport->tty, NULL);
+ else
+ tty_port_open(serport->port, tty, NULL);
+
+ /* Bring the UART into a known 8 bits no parity hw fc state */
+ ktermios = tty->termios;
+ ktermios.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP |
+ INLCR | IGNCR | ICRNL | IXON);
+ ktermios.c_oflag &= ~OPOST;
+ ktermios.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
+ ktermios.c_cflag &= ~(CSIZE | PARENB);
+ ktermios.c_cflag |= CS8;
+ ktermios.c_cflag |= CRTSCTS;
+ tty_set_termios(tty, &ktermios);
+
+ set_bit(SERPORT_ACTIVE, &serport->flags);
+
+ tty_unlock(serport->tty);
+ return 0;
+}
+
+static void ttyport_close(struct serdev_controller *ctrl)
+{
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+ struct tty_struct *tty = serport->tty;
+
+ clear_bit(SERPORT_ACTIVE, &serport->flags);
+
+ if (tty->ops->close)
+ tty->ops->close(tty, NULL);
+
+ tty_release_struct(tty, serport->tty_idx);
+}
+
+static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigned int speed)
+{
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+ struct tty_struct *tty = serport->tty;
+ struct ktermios ktermios = tty->termios;
+
+ ktermios.c_cflag &= ~CBAUD;
+ tty_termios_encode_baud_rate(&ktermios, speed, speed);
+
+ /* tty_set_termios() return not checked as it is always 0 */
+ tty_set_termios(tty, &ktermios);
+ return speed;
+}
+
+static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable)
+{
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+ struct tty_struct *tty = serport->tty;
+ struct ktermios ktermios = tty->termios;
+
+ if (enable)
+ ktermios.c_cflag |= CRTSCTS;
+ else
+ ktermios.c_cflag &= ~CRTSCTS;
+
+ tty_set_termios(tty, &ktermios);
+}
+
+static const struct serdev_controller_ops ctrl_ops = {
+ .write_buf = ttyport_write_buf,
+ .write_flush = ttyport_write_flush,
+ .write_room = ttyport_write_room,
+ .open = ttyport_open,
+ .close = ttyport_close,
+ .set_flow_control = ttyport_set_flow_control,
+ .set_baudrate = ttyport_set_baudrate,
+};
+
+struct device *serdev_tty_port_register(struct tty_port *port,
+ struct device *parent,
+ struct tty_driver *drv, int idx)
+{
+ struct serdev_controller *ctrl;
+ struct serport *serport;
+ int ret;
+
+ if (!port || !drv || !parent)
+ return ERR_PTR(-ENODEV);
+
+ ctrl = serdev_controller_alloc(parent, sizeof(struct serport));
+ if (!ctrl)
+ return ERR_PTR(-ENOMEM);
+ serport = serdev_controller_get_drvdata(ctrl);
+
+ serport->port = port;
+ serport->tty_idx = idx;
+ serport->tty_drv = drv;
+
+ ctrl->ops = &ctrl_ops;
+
+ ret = serdev_controller_add(ctrl);
+ if (ret)
+ goto err_controller_put;
+
+ dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx);
+ return &ctrl->dev;
+
+err_controller_put:
+ serdev_controller_put(ctrl);
+ return ERR_PTR(ret);
+}
+
+void serdev_tty_port_unregister(struct tty_port *port)
+{
+ struct serdev_controller *ctrl = port->client_data;
+ struct serport *serport = serdev_controller_get_drvdata(ctrl);
+
+ if (!serport)
+ return;
+
+ serdev_controller_remove(ctrl);
+ port->client_ops = NULL;
+ port->client_data = NULL;
+ serdev_controller_put(ctrl);
+}
diff --git a/include/linux/serdev.h b/include/linux/serdev.h
index 3ac26c1a8aab..9519da6253a8 100644
--- a/include/linux/serdev.h
+++ b/include/linux/serdev.h
@@ -238,4 +238,25 @@ static inline int serdev_device_write_room(struct serdev_device *sdev)
#endif /* CONFIG_SERIAL_DEV_BUS */
+/*
+ * serdev hooks into TTY core
+ */
+struct tty_port;
+struct tty_driver;
+
+#ifdef CONFIG_SERIAL_DEV_CTRL_TTYPORT
+struct device *serdev_tty_port_register(struct tty_port *port,
+ struct device *parent,
+ struct tty_driver *drv, int idx);
+void serdev_tty_port_unregister(struct tty_port *port);
+#else
+static inline struct device *serdev_tty_port_register(struct tty_port *port,
+ struct device *parent,
+ struct tty_driver *drv, int idx)
+{
+ return ERR_PTR(-ENODEV);
+}
+static inline void serdev_tty_port_unregister(struct tty_port *port) {}
+#endif /* CONFIG_SERIAL_DEV_CTRL_TTYPORT */
+
#endif /*_LINUX_SERDEV_H */
--
2.10.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH v4 5/5] tty_port: register tty ports with serdev bus
2017-02-02 19:48 [PATCH v4 0/5] Serial slave device bus Rob Herring
` (3 preceding siblings ...)
2017-02-02 19:48 ` [PATCH v4 4/5] serdev: add a tty port controller driver Rob Herring
@ 2017-02-02 19:48 ` Rob Herring
4 siblings, 0 replies; 6+ messages in thread
From: Rob Herring @ 2017-02-02 19:48 UTC (permalink / raw)
To: Greg Kroah-Hartman, Marcel Holtmann, Jiri Slaby,
Sebastian Reichel, Arnd Bergmann, Dr . H . Nikolaus Schaller,
Peter Hurley, Andy Shevchenko, Alan Cox
Cc: Loic Poulain, Pavel Machek, NeilBrown, Linus Walleij,
linux-bluetooth, linux-serial, linux-kernel
Register a serdev controller with the serdev bus when a tty_port is
registered. This creates the serdev controller and create's serdev
devices for any DT child nodes of the tty_port's parent (i.e. the UART
device).
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-By: Sebastian Reichel <sre@kernel.org>
Tested-By: Sebastian Reichel <sre@kernel.org>
---
v4:
- no change
v3:
- no change
v2:
- Skip creating the tty device file node when serdev_tty_port_register
finds slave devices.
drivers/tty/tty_port.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c
index 8d9886b06037..5cd3cd932293 100644
--- a/drivers/tty/tty_port.c
+++ b/drivers/tty/tty_port.c
@@ -16,6 +16,7 @@
#include <linux/bitops.h>
#include <linux/delay.h>
#include <linux/module.h>
+#include <linux/serdev.h>
static int tty_port_default_receive_buf(struct tty_port *port,
const unsigned char *p,
@@ -128,7 +129,15 @@ struct device *tty_port_register_device_attr(struct tty_port *port,
struct device *device, void *drvdata,
const struct attribute_group **attr_grp)
{
+ struct device *dev;
+
tty_port_link_device(port, driver, index);
+
+ dev = serdev_tty_port_register(port, device, driver, index);
+ if (PTR_ERR(dev) != -ENODEV)
+ /* Skip creating cdev if we registered a serdev device */
+ return dev;
+
return tty_register_device_attr(driver, index, device, drvdata,
attr_grp);
}
@@ -180,6 +189,9 @@ static void tty_port_destructor(struct kref *kref)
/* check if last port ref was dropped before tty release */
if (WARN_ON(port->itty))
return;
+
+ serdev_tty_port_unregister(port);
+
if (port->xmit_buf)
free_page((unsigned long)port->xmit_buf);
tty_port_destroy(port);
--
2.10.1
^ permalink raw reply related [flat|nested] 6+ messages in thread