Hi, This patch adds a virtio driver for input devices. Specification: https://www.kraxel.org/cgit/virtio-spec/log/?h=virtio-input https://www.kraxel.org/virtio/virtio-v1.0-csprd03-virtio-input.html#x1-2640007 Qemu patches; https://lists.gnu.org/archive/html/qemu-devel/2015-03/threads.html#03973 Gerd Hoffmann (1): Add virtio-input driver. drivers/virtio/Kconfig | 10 ++ drivers/virtio/Makefile | 1 + drivers/virtio/virtio_input.c | 313 ++++++++++++++++++++++++++++++++++++++ include/uapi/linux/virtio_ids.h | 1 + include/uapi/linux/virtio_input.h | 65 ++++++++ 5 files changed, 390 insertions(+) create mode 100644 drivers/virtio/virtio_input.c create mode 100644 include/uapi/linux/virtio_input.h -- 1.8.3.1
virtio-input is basically evdev-events-over-virtio, so this driver isn't
much more than reading configuration from config space and forwarding
incoming events to the linux input layer.
Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>
---
drivers/virtio/Kconfig | 10 ++
drivers/virtio/Makefile | 1 +
drivers/virtio/virtio_input.c | 313 ++++++++++++++++++++++++++++++++++++++
include/uapi/linux/virtio_ids.h | 1 +
include/uapi/linux/virtio_input.h | 65 ++++++++
5 files changed, 390 insertions(+)
create mode 100644 drivers/virtio/virtio_input.c
create mode 100644 include/uapi/linux/virtio_input.h
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index b546da5..cab9f3f 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -48,6 +48,16 @@ config VIRTIO_BALLOON
If unsure, say M.
+config VIRTIO_INPUT
+ tristate "Virtio input driver"
+ depends on VIRTIO
+ depends on INPUT
+ ---help---
+ This driver supports virtio input devices such as
+ keyboards, mice and tablets.
+
+ If unsure, say M.
+
config VIRTIO_MMIO
tristate "Platform bus driver for memory mapped virtio devices"
depends on HAS_IOMEM
diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile
index d85565b..41e30e3 100644
--- a/drivers/virtio/Makefile
+++ b/drivers/virtio/Makefile
@@ -4,3 +4,4 @@ obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o
virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o
virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o
obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o
+obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o
diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c
new file mode 100644
index 0000000..2d425cf
--- /dev/null
+++ b/drivers/virtio/virtio_input.c
@@ -0,0 +1,313 @@
+#include <linux/module.h>
+#include <linux/virtio.h>
+#include <linux/input.h>
+
+#include <uapi/linux/virtio_ids.h>
+#include <uapi/linux/virtio_input.h>
+
+struct virtio_input {
+ struct virtio_device *vdev;
+ struct input_dev *idev;
+ char name[64];
+ char serial[64];
+ char phys[64];
+ struct virtqueue *evt, *sts;
+ struct virtio_input_event evts[64];
+};
+
+static ssize_t serial_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct input_dev *idev = to_input_dev(dev);
+ struct virtio_input *vi = input_get_drvdata(idev);
+ return sprintf(buf, "%s\n", vi->serial);
+}
+static DEVICE_ATTR_RO(serial);
+
+static struct attribute *dev_attrs[] = {
+ &dev_attr_serial.attr,
+ NULL
+};
+
+static umode_t dev_attrs_are_visible(struct kobject *kobj,
+ struct attribute *a, int n)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ struct input_dev *idev = to_input_dev(dev);
+ struct virtio_input *vi = input_get_drvdata(idev);
+
+ if (a == &dev_attr_serial.attr && !strlen(vi->serial))
+ return 0;
+
+ return a->mode;
+}
+
+static struct attribute_group dev_attr_grp = {
+ .attrs = dev_attrs,
+ .is_visible = dev_attrs_are_visible,
+};
+
+static const struct attribute_group *dev_attr_groups[] = {
+ &dev_attr_grp,
+ NULL
+};
+
+static void virtinput_queue_evtbuf(struct virtio_input *vi,
+ struct virtio_input_event *evtbuf)
+{
+ struct scatterlist sg[1];
+
+ sg_init_one(sg, evtbuf, sizeof(*evtbuf));
+ virtqueue_add_inbuf(vi->evt, sg, 1, evtbuf, GFP_ATOMIC);
+}
+
+static void virtinput_recv_events(struct virtqueue *vq)
+{
+ struct virtio_input *vi = vq->vdev->priv;
+ struct virtio_input_event *event;
+ unsigned int len;
+
+ while ((event = virtqueue_get_buf(vi->evt, &len)) != NULL) {
+ input_event(vi->idev,
+ le16_to_cpu(event->type),
+ le16_to_cpu(event->code),
+ le32_to_cpu(event->value));
+ virtinput_queue_evtbuf(vi, event);
+ }
+ virtqueue_kick(vq);
+}
+
+static int virtinput_send_status(struct virtio_input *vi,
+ u16 type, u16 code, s32 value)
+{
+ struct virtio_input_event *stsbuf;
+ struct scatterlist sg[1];
+
+ stsbuf = kzalloc(sizeof(*stsbuf), GFP_ATOMIC);
+ if (!stsbuf)
+ return -ENOMEM;
+
+ stsbuf->type = cpu_to_le16(type);
+ stsbuf->code = cpu_to_le16(code);
+ stsbuf->value = cpu_to_le32(value);
+ sg_init_one(sg, stsbuf, sizeof(*stsbuf));
+ virtqueue_add_outbuf(vi->sts, sg, 1, stsbuf, GFP_ATOMIC);
+ virtqueue_kick(vi->sts);
+ return 0;
+}
+
+static void virtinput_recv_status(struct virtqueue *vq)
+{
+ struct virtio_input *vi = vq->vdev->priv;
+ struct virtio_input_event *stsbuf;
+ unsigned int len;
+
+ while ((stsbuf = virtqueue_get_buf(vi->sts, &len)) != NULL)
+ kfree(stsbuf);
+ virtqueue_kick(vq);
+}
+
+static int virtinput_status(struct input_dev *idev, unsigned int type,
+ unsigned int code, int value)
+{
+ struct virtio_input *vi = input_get_drvdata(idev);
+
+ return virtinput_send_status(vi, type, code, value);
+}
+
+static size_t virtinput_cfg_select(struct virtio_input *vi,
+ u8 select, u8 subsel)
+{
+ u8 size;
+
+ virtio_cwrite(vi->vdev, struct virtio_input_config, select, &select);
+ virtio_cwrite(vi->vdev, struct virtio_input_config, subsel, &subsel);
+ virtio_cread(vi->vdev, struct virtio_input_config, size, &size);
+ return size;
+}
+
+static void virtinput_cfg_bits(struct virtio_input *vi, int select, int subsel,
+ unsigned long *bits, unsigned int bitcount)
+{
+ unsigned int bit;
+ size_t bytes;
+ u8 cfg = 0;
+
+ bytes = virtinput_cfg_select(vi, select, subsel);
+ if (!bytes)
+ return;
+ if (bitcount > bytes*8)
+ bitcount = bytes*8;
+ if (select == VIRTIO_INPUT_CFG_EV_BITS)
+ set_bit(subsel, vi->idev->evbit);
+ for (bit = 0; bit < bitcount; bit++) {
+ if ((bit % 8) == 0)
+ virtio_cread(vi->vdev, struct virtio_input_config,
+ u.bitmap[bit/8], &cfg);
+ if (cfg & (1 << (bit % 8)))
+ set_bit(bit, bits);
+ }
+}
+
+static void virtinput_cfg_abs(struct virtio_input *vi, int abs)
+{
+ u32 size, mi, ma, fu, fl;
+
+ size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ABS_INFO, abs);
+ virtio_cread(vi->vdev, struct virtio_input_config, u.abs.min, &mi);
+ virtio_cread(vi->vdev, struct virtio_input_config, u.abs.max, &ma);
+ virtio_cread(vi->vdev, struct virtio_input_config, u.abs.fuzz, &fu);
+ virtio_cread(vi->vdev, struct virtio_input_config, u.abs.flat, &fl);
+ input_set_abs_params(vi->idev, abs,
+ le32_to_cpu(mi), le32_to_cpu(ma),
+ le32_to_cpu(fu), le32_to_cpu(fl));
+}
+
+static int virtinput_init_vqs(struct virtio_input *vi)
+{
+ struct virtqueue *vqs[2];
+ vq_callback_t *cbs[] = { virtinput_recv_events,
+ virtinput_recv_status };
+ const char *names[] = { "events", "status" };
+ int i, err, size;
+
+ err = vi->vdev->config->find_vqs(vi->vdev, 2, vqs, cbs, names);
+ if (err)
+ return err;
+ vi->evt = vqs[0];
+ vi->sts = vqs[1];
+
+ size = virtqueue_get_vring_size(vi->evt);
+ if (size > ARRAY_SIZE(vi->evts))
+ size = ARRAY_SIZE(vi->evts);
+ for (i = 0; i < size; i++)
+ virtinput_queue_evtbuf(vi, &vi->evts[i]);
+
+ return 0;
+}
+
+static int virtinput_probe(struct virtio_device *vdev)
+{
+ struct virtio_input *vi;
+ size_t size;
+ int abs, err;
+
+ vi = kzalloc(sizeof(*vi), GFP_KERNEL);
+ if (!vi) {
+ err = -ENOMEM;
+ goto out1;
+ }
+ vdev->priv = vi;
+ vi->vdev = vdev;
+
+ err = virtinput_init_vqs(vi);
+ if (err)
+ goto out2;
+
+ vi->idev = input_allocate_device();
+ if (!vi->idev) {
+ err = -ENOMEM;
+ goto out3;
+ }
+ input_set_drvdata(vi->idev, vi);
+
+ size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_NAME, 0);
+ virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, u),
+ vi->name, min(size, sizeof(vi->name)));
+ size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_SERIAL, 0);
+ virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, u),
+ vi->serial, min(size, sizeof(vi->serial)));
+ snprintf(vi->phys, sizeof(vi->phys),
+ "virtio%d/input0", vdev->index);
+
+ virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_PROP_BITS, 0,
+ vi->idev->propbit, INPUT_PROP_CNT);
+ size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REP);
+ if (size)
+ set_bit(EV_REP, vi->idev->evbit);
+
+ vi->idev->name = vi->name;
+ vi->idev->phys = vi->phys;
+ vi->idev->id.bustype = BUS_VIRTUAL;
+ vi->idev->id.vendor = 0x0001;
+ vi->idev->id.product = 0x0001;
+ vi->idev->id.version = 0x0100;
+ vi->idev->dev.parent = &vdev->dev;
+ vi->idev->dev.groups = dev_attr_groups;
+ vi->idev->event = virtinput_status;
+
+ /* device -> kernel */
+ virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_KEY,
+ vi->idev->keybit, KEY_CNT);
+ virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REL,
+ vi->idev->relbit, REL_CNT);
+ virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_ABS,
+ vi->idev->absbit, ABS_CNT);
+ virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_MSC,
+ vi->idev->mscbit, MSC_CNT);
+ virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SW,
+ vi->idev->swbit, SW_CNT);
+
+ /* kernel -> device */
+ virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_LED,
+ vi->idev->ledbit, LED_CNT);
+ virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SND,
+ vi->idev->sndbit, SND_CNT);
+
+ if (test_bit(EV_ABS, vi->idev->evbit)) {
+ for (abs = 0; abs < ABS_CNT; abs++) {
+ if (!test_bit(abs, vi->idev->absbit))
+ continue;
+ virtinput_cfg_abs(vi, abs);
+ }
+ }
+
+ err = input_register_device(vi->idev);
+ if (err)
+ goto out4;
+
+ return 0;
+
+out4:
+ input_free_device(vi->idev);
+out3:
+ vdev->config->del_vqs(vdev);
+out2:
+ kfree(vi);
+out1:
+ return err;
+}
+
+static void virtinput_remove(struct virtio_device *vdev)
+{
+ struct virtio_input *vi = vdev->priv;
+
+ input_unregister_device(vi->idev);
+ vdev->config->reset(vdev);
+ vdev->config->del_vqs(vdev);
+ kfree(vi);
+}
+
+static unsigned int features[] = {
+};
+static struct virtio_device_id id_table[] = {
+ { VIRTIO_ID_INPUT, VIRTIO_DEV_ANY_ID },
+ { 0 },
+};
+
+static struct virtio_driver virtio_input_driver = {
+ .driver.name = KBUILD_MODNAME,
+ .driver.owner = THIS_MODULE,
+ .feature_table = features,
+ .feature_table_size = ARRAY_SIZE(features),
+ .id_table = id_table,
+ .probe = virtinput_probe,
+ .remove = virtinput_remove,
+};
+
+module_virtio_driver(virtio_input_driver);
+MODULE_DEVICE_TABLE(virtio, id_table);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Virtio input device driver");
+MODULE_AUTHOR("Gerd Hoffmann <kraxel at redhat.com>");
diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h
index 284fc3a..5f60aa4 100644
--- a/include/uapi/linux/virtio_ids.h
+++ b/include/uapi/linux/virtio_ids.h
@@ -39,5 +39,6 @@
#define VIRTIO_ID_9P 9 /* 9p virtio console */
#define VIRTIO_ID_RPROC_SERIAL 11 /* virtio remoteproc serial link */
#define VIRTIO_ID_CAIF 12 /* Virtio caif */
+#define VIRTIO_ID_INPUT 18 /* virtio input */
#endif /* _LINUX_VIRTIO_IDS_H */
diff --git a/include/uapi/linux/virtio_input.h
b/include/uapi/linux/virtio_input.h
new file mode 100644
index 0000000..190d04a
--- /dev/null
+++ b/include/uapi/linux/virtio_input.h
@@ -0,0 +1,65 @@
+#ifndef _LINUX_VIRTIO_INPUT_H
+#define _LINUX_VIRTIO_INPUT_H
+/* This header is BSD licensed so anyone can use the definitions to implement
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
+#include <linux/virtio_ids.h>
+#include <linux/virtio_config.h>
+
+enum virtio_input_config_select {
+ VIRTIO_INPUT_CFG_UNSET = 0x00,
+ VIRTIO_INPUT_CFG_ID_NAME = 0x01,
+ VIRTIO_INPUT_CFG_ID_SERIAL = 0x02,
+ VIRTIO_INPUT_CFG_PROP_BITS = 0x10,
+ VIRTIO_INPUT_CFG_EV_BITS = 0x11,
+ VIRTIO_INPUT_CFG_ABS_INFO = 0x12,
+};
+
+struct virtio_input_absinfo {
+ __le32 min;
+ __le32 max;
+ __le32 fuzz;
+ __le32 flat;
+};
+
+struct virtio_input_config {
+ __u8 select;
+ __u8 subsel;
+ __u8 size;
+ __u8 reserved;
+ union {
+ char string[128];
+ __u8 bitmap[128];
+ struct virtio_input_absinfo abs;
+ } u;
+};
+
+struct virtio_input_event {
+ __le16 type;
+ __le16 code;
+ __le32 value;
+};
+
+#endif /* _LINUX_VIRTIO_INPUT_H */
--
1.8.3.1
On Thu, Mar 19, 2015 at 10:13:11AM +0100, Gerd Hoffmann wrote:> virtio-input is basically evdev-events-over-virtio, so this driver isn't > much more than reading configuration from config space and forwarding > incoming events to the linux input layer. > > Signed-off-by: Gerd Hoffmann <kraxel at redhat.com>What worries me is how well are these events specified. Will we be able to write drivers for non-linux guests? Not sure where to discuss this - this seems like an inappropriate thread. Comments on linux driver below.> --- > drivers/virtio/Kconfig | 10 ++ > drivers/virtio/Makefile | 1 + > drivers/virtio/virtio_input.c | 313 ++++++++++++++++++++++++++++++++++++++ > include/uapi/linux/virtio_ids.h | 1 + > include/uapi/linux/virtio_input.h | 65 ++++++++ > 5 files changed, 390 insertions(+) > create mode 100644 drivers/virtio/virtio_input.c > create mode 100644 include/uapi/linux/virtio_input.h > > diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig > index b546da5..cab9f3f 100644 > --- a/drivers/virtio/Kconfig > +++ b/drivers/virtio/Kconfig > @@ -48,6 +48,16 @@ config VIRTIO_BALLOON > > If unsure, say M. > > +config VIRTIO_INPUT > + tristate "Virtio input driver" > + depends on VIRTIO > + depends on INPUT > + ---help--- > + This driver supports virtio input devices such as > + keyboards, mice and tablets. > + > + If unsure, say M. > + > config VIRTIO_MMIO > tristate "Platform bus driver for memory mapped virtio devices" > depends on HAS_IOMEM > diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile > index d85565b..41e30e3 100644 > --- a/drivers/virtio/Makefile > +++ b/drivers/virtio/Makefile > @@ -4,3 +4,4 @@ obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o > virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o > virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o > obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o > +obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o > diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c > new file mode 100644 > index 0000000..2d425cf > --- /dev/null > +++ b/drivers/virtio/virtio_input.c > @@ -0,0 +1,313 @@ > +#include <linux/module.h> > +#include <linux/virtio.h> > +#include <linux/input.h> > + > +#include <uapi/linux/virtio_ids.h> > +#include <uapi/linux/virtio_input.h> > + > +struct virtio_input { > + struct virtio_device *vdev; > + struct input_dev *idev; > + char name[64]; > + char serial[64]; > + char phys[64]; > + struct virtqueue *evt, *sts; > + struct virtio_input_event evts[64]; > +}; > + > +static ssize_t serial_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct input_dev *idev = to_input_dev(dev); > + struct virtio_input *vi = input_get_drvdata(idev); > + return sprintf(buf, "%s\n", vi->serial); > +} > +static DEVICE_ATTR_RO(serial); > + > +static struct attribute *dev_attrs[] = { > + &dev_attr_serial.attr, > + NULL > +}; > + > +static umode_t dev_attrs_are_visible(struct kobject *kobj, > + struct attribute *a, int n) > +{ > + struct device *dev = container_of(kobj, struct device, kobj); > + struct input_dev *idev = to_input_dev(dev); > + struct virtio_input *vi = input_get_drvdata(idev); > + > + if (a == &dev_attr_serial.attr && !strlen(vi->serial)) > + return 0; > + > + return a->mode; > +} > + > +static struct attribute_group dev_attr_grp = { > + .attrs = dev_attrs, > + .is_visible = dev_attrs_are_visible, > +}; > + > +static const struct attribute_group *dev_attr_groups[] = { > + &dev_attr_grp, > + NULL > +}; > + > +static void virtinput_queue_evtbuf(struct virtio_input *vi, > + struct virtio_input_event *evtbuf) > +{ > + struct scatterlist sg[1]; > + > + sg_init_one(sg, evtbuf, sizeof(*evtbuf)); > + virtqueue_add_inbuf(vi->evt, sg, 1, evtbuf, GFP_ATOMIC); > +} > + > +static void virtinput_recv_events(struct virtqueue *vq) > +{ > + struct virtio_input *vi = vq->vdev->priv; > + struct virtio_input_event *event; > + unsigned int len; > + > + while ((event = virtqueue_get_buf(vi->evt, &len)) != NULL) { > + input_event(vi->idev, > + le16_to_cpu(event->type), > + le16_to_cpu(event->code), > + le32_to_cpu(event->value)); > + virtinput_queue_evtbuf(vi, event); > + } > + virtqueue_kick(vq); > +} > + > +static int virtinput_send_status(struct virtio_input *vi, > + u16 type, u16 code, s32 value) > +{ > + struct virtio_input_event *stsbuf; > + struct scatterlist sg[1]; > + > + stsbuf = kzalloc(sizeof(*stsbuf), GFP_ATOMIC); > + if (!stsbuf) > + return -ENOMEM;Does this return an error to userspace? If so it's not a good idea I think, GFP_ATOMIC failures are transient conditions and should not be reported to userspace. Can use GFP_KERNEL here?> + > + stsbuf->type = cpu_to_le16(type); > + stsbuf->code = cpu_to_le16(code); > + stsbuf->value = cpu_to_le32(value); > + sg_init_one(sg, stsbuf, sizeof(*stsbuf)); > + virtqueue_add_outbuf(vi->sts, sg, 1, stsbuf, GFP_ATOMIC);This can fail if queue is full. What prevents this from happening?> + virtqueue_kick(vi->sts);Also what prevents multiple virtinput_send_status calls from racing with each other? Is there locking at a higher level?> + return 0; > +} > + > +static void virtinput_recv_status(struct virtqueue *vq) > +{ > + struct virtio_input *vi = vq->vdev->priv; > + struct virtio_input_event *stsbuf; > + unsigned int len; > + > + while ((stsbuf = virtqueue_get_buf(vi->sts, &len)) != NULL)looks like this get_buf can race with add above. Need some locking. Also pls avoid != NULL, removing it makes code less verbose.> + kfree(stsbuf); > + virtqueue_kick(vq);Why are you kicking here?> +} > + > +static int virtinput_status(struct input_dev *idev, unsigned int type, > + unsigned int code, int value) > +{ > + struct virtio_input *vi = input_get_drvdata(idev); > + > + return virtinput_send_status(vi, type, code, value); > +} > + > +static size_t virtinput_cfg_select(struct virtio_input *vi, > + u8 select, u8 subsel) > +{ > + u8 size; > + > + virtio_cwrite(vi->vdev, struct virtio_input_config, select, &select); > + virtio_cwrite(vi->vdev, struct virtio_input_config, subsel, &subsel); > + virtio_cread(vi->vdev, struct virtio_input_config, size, &size); > + return size; > +} > + > +static void virtinput_cfg_bits(struct virtio_input *vi, int select, int subsel, > + unsigned long *bits, unsigned int bitcount) > +{ > + unsigned int bit; > + size_t bytes; > + u8 cfg = 0; > + > + bytes = virtinput_cfg_select(vi, select, subsel); > + if (!bytes) > + return; > + if (bitcount > bytes*8) > + bitcount = bytes*8; > + if (select == VIRTIO_INPUT_CFG_EV_BITS) > + set_bit(subsel, vi->idev->evbit); > + for (bit = 0; bit < bitcount; bit++) { > + if ((bit % 8) == 0) > + virtio_cread(vi->vdev, struct virtio_input_config, > + u.bitmap[bit/8], &cfg);coding style violations above. you need spaces around ops like / and *. Please run checkpatch.pl> + if (cfg & (1 << (bit % 8))) > + set_bit(bit, bits);what if not set? does something clear the mask?> + }doesn't above just implement bitmap_copy or bitmap_or? Will it hurt to just do virtio_cread_bytes into a temporary buffer and then invoke bitmap ops? Looks like the buffer is at most 256 bytes: too large to be on stack, but you can allocate it at probe time.> +} > + > +static void virtinput_cfg_abs(struct virtio_input *vi, int abs) > +{ > + u32 size, mi, ma, fu, fl; > + > + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ABS_INFO, abs); > + virtio_cread(vi->vdev, struct virtio_input_config, u.abs.min, &mi); > + virtio_cread(vi->vdev, struct virtio_input_config, u.abs.max, &ma); > + virtio_cread(vi->vdev, struct virtio_input_config, u.abs.fuzz, &fu); > + virtio_cread(vi->vdev, struct virtio_input_config, u.abs.flat, &fl);you read le field into u32 value. Please run sparse on this code. you will get a ton of warnings. Same error appears elsewhere.> + input_set_abs_params(vi->idev, abs, > + le32_to_cpu(mi), le32_to_cpu(ma), > + le32_to_cpu(fu), le32_to_cpu(fl)); > +} > + > +static int virtinput_init_vqs(struct virtio_input *vi) > +{ > + struct virtqueue *vqs[2]; > + vq_callback_t *cbs[] = { virtinput_recv_events, > + virtinput_recv_status }; > + const char *names[] = { "events", "status" }; > + int i, err, size; > + > + err = vi->vdev->config->find_vqs(vi->vdev, 2, vqs, cbs, names); > + if (err) > + return err; > + vi->evt = vqs[0]; > + vi->sts = vqs[1]; > + > + size = virtqueue_get_vring_size(vi->evt); > + if (size > ARRAY_SIZE(vi->evts)) > + size = ARRAY_SIZE(vi->evts); > + for (i = 0; i < size; i++) > + virtinput_queue_evtbuf(vi, &vi->evts[i]); > +you add a bunch of bufs but never kick apparently. you really must kick otherwise device might not see the buffers.> + return 0; > +} > + > +static int virtinput_probe(struct virtio_device *vdev) > +{ > + struct virtio_input *vi; > + size_t size; > + int abs, err;How about checking VERSION_1 and bailing out of not there?> + > + vi = kzalloc(sizeof(*vi), GFP_KERNEL); > + if (!vi) { > + err = -ENOMEM; > + goto out1; > + } > + vdev->priv = vi; > + vi->vdev = vdev; > + > + err = virtinput_init_vqs(vi); > + if (err) > + goto out2; > + > + vi->idev = input_allocate_device(); > + if (!vi->idev) { > + err = -ENOMEM; > + goto out3; > + } > + input_set_drvdata(vi->idev, vi); > + > + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_NAME, 0); > + virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, u), > + vi->name, min(size, sizeof(vi->name))); > + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_SERIAL, 0); > + virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, u), > + vi->serial, min(size, sizeof(vi->serial))); > + snprintf(vi->phys, sizeof(vi->phys), > + "virtio%d/input0", vdev->index); > + > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_PROP_BITS, 0, > + vi->idev->propbit, INPUT_PROP_CNT); > + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REP); > + if (size) > + set_bit(EV_REP, vi->idev->evbit); > + > + vi->idev->name = vi->name; > + vi->idev->phys = vi->phys; > + vi->idev->id.bustype = BUS_VIRTUAL; > + vi->idev->id.vendor = 0x0001; > + vi->idev->id.product = 0x0001; > + vi->idev->id.version = 0x0100;Add comments explaining why these #s make sense?> + vi->idev->dev.parent = &vdev->dev; > + vi->idev->dev.groups = dev_attr_groups; > + vi->idev->event = virtinput_status; > + > + /* device -> kernel */ > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_KEY, > + vi->idev->keybit, KEY_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REL, > + vi->idev->relbit, REL_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_ABS, > + vi->idev->absbit, ABS_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_MSC, > + vi->idev->mscbit, MSC_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SW, > + vi->idev->swbit, SW_CNT); > + > + /* kernel -> device */ > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_LED, > + vi->idev->ledbit, LED_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SND, > + vi->idev->sndbit, SND_CNT); > + > + if (test_bit(EV_ABS, vi->idev->evbit)) { > + for (abs = 0; abs < ABS_CNT; abs++) { > + if (!test_bit(abs, vi->idev->absbit)) > + continue; > + virtinput_cfg_abs(vi, abs); > + } > + } > + > + err = input_register_device(vi->idev);Once you do this, virtinput_status can get called, and that will kick, correct? If so, you must call device_ready before this.> + if (err) > + goto out4; > + > + return 0; > + > +out4: > + input_free_device(vi->idev); > +out3: > + vdev->config->del_vqs(vdev); > +out2: > + kfree(vi); > +out1: > + return err;free on error is out of order with initialization. Might lead to leaks or other bugs. Also - can you name labels something sensible pls? out is usually for exiting on success too... E.g. out4 -> err_register etc.> +} > + > +static void virtinput_remove(struct virtio_device *vdev) > +{ > + struct virtio_input *vi = vdev->priv; > + > + input_unregister_device(vi->idev); > + vdev->config->reset(vdev);You don't really need a reset if you just to del_vqs. People do this if they want to prevent interrupts without deleting vqs.> + vdev->config->del_vqs(vdev); > + kfree(vi);free_device seems to be missing?> +} > + > +static unsigned int features[] = { > +}; > +static struct virtio_device_id id_table[] = { > + { VIRTIO_ID_INPUT, VIRTIO_DEV_ANY_ID }, > + { 0 }, > +}; > + > +static struct virtio_driver virtio_input_driver = { > + .driver.name = KBUILD_MODNAME, > + .driver.owner = THIS_MODULE, > + .feature_table = features, > + .feature_table_size = ARRAY_SIZE(features), > + .id_table = id_table, > + .probe = virtinput_probe, > + .remove = virtinput_remove, > +}; > + > +module_virtio_driver(virtio_input_driver); > +MODULE_DEVICE_TABLE(virtio, id_table); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Virtio input device driver"); > +MODULE_AUTHOR("Gerd Hoffmann <kraxel at redhat.com>"); > diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h > index 284fc3a..5f60aa4 100644 > --- a/include/uapi/linux/virtio_ids.h > +++ b/include/uapi/linux/virtio_ids.h > @@ -39,5 +39,6 @@ > #define VIRTIO_ID_9P 9 /* 9p virtio console */ > #define VIRTIO_ID_RPROC_SERIAL 11 /* virtio remoteproc serial link */ > #define VIRTIO_ID_CAIF 12 /* Virtio caif */ > +#define VIRTIO_ID_INPUT 18 /* virtio input */ > > #endif /* _LINUX_VIRTIO_IDS_H */ > diff --git a/include/uapi/linux/virtio_input.h b/include/uapi/linux/virtio_input.h > new file mode 100644 > index 0000000..190d04a > --- /dev/null > +++ b/include/uapi/linux/virtio_input.h > @@ -0,0 +1,65 @@ > +#ifndef _LINUX_VIRTIO_INPUT_H > +#define _LINUX_VIRTIO_INPUT_H > +/* This header is BSD licensed so anyone can use the definitions to implement > + * compatible drivers/servers. > + * > + * Redistribution and use in source and binary forms, with or without > + * modification, are permitted provided that the following conditions > + * are met: > + * 1. Redistributions of source code must retain the above copyright > + * notice, this list of conditions and the following disclaimer. > + * 2. Redistributions in binary form must reproduce the above copyright > + * notice, this list of conditions and the following disclaimer in the > + * documentation and/or other materials provided with the distribution. > + * 3. Neither the name of IBM nor the names of its contributors > + * may be used to endorse or promote products derived from this software > + * without specific prior written permission. > + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND > + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE > + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE > + * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE > + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL > + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS > + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) > + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT > + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY > + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF > + * SUCH DAMAGE. */ > +#include <linux/virtio_ids.h> > +#include <linux/virtio_config.h> > + > +enum virtio_input_config_select { > + VIRTIO_INPUT_CFG_UNSET = 0x00, > + VIRTIO_INPUT_CFG_ID_NAME = 0x01, > + VIRTIO_INPUT_CFG_ID_SERIAL = 0x02, > + VIRTIO_INPUT_CFG_PROP_BITS = 0x10, > + VIRTIO_INPUT_CFG_EV_BITS = 0x11, > + VIRTIO_INPUT_CFG_ABS_INFO = 0x12, > +}; > + > +struct virtio_input_absinfo { > + __le32 min; > + __le32 max; > + __le32 fuzz; > + __le32 flat; > +}; > + > +struct virtio_input_config { > + __u8 select; > + __u8 subsel; > + __u8 size; > + __u8 reserved; > + union { > + char string[128]; > + __u8 bitmap[128]; > + struct virtio_input_absinfo abs; > + } u; > +}; > + > +struct virtio_input_event { > + __le16 type; > + __le16 code; > + __le32 value; > +}; > + > +#endif /* _LINUX_VIRTIO_INPUT_H */ > -- > 1.8.3.1
Hi (CC: Dmitry) On Thu, Mar 19, 2015 at 10:13 AM, Gerd Hoffmann <kraxel at redhat.com> wrote:> virtio-input is basically evdev-events-over-virtio, so this driver isn't > much more than reading configuration from config space and forwarding > incoming events to the linux input layer. > > Signed-off-by: Gerd Hoffmann <kraxel at redhat.com> > --- > drivers/virtio/Kconfig | 10 ++ > drivers/virtio/Makefile | 1 + > drivers/virtio/virtio_input.c | 313 ++++++++++++++++++++++++++++++++++++++ > include/uapi/linux/virtio_ids.h | 1 + > include/uapi/linux/virtio_input.h | 65 ++++++++ > 5 files changed, 390 insertions(+) > create mode 100644 drivers/virtio/virtio_input.c > create mode 100644 include/uapi/linux/virtio_input.h > > diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig > index b546da5..cab9f3f 100644 > --- a/drivers/virtio/Kconfig > +++ b/drivers/virtio/Kconfig > @@ -48,6 +48,16 @@ config VIRTIO_BALLOON > > If unsure, say M. > > +config VIRTIO_INPUT > + tristate "Virtio input driver" > + depends on VIRTIO > + depends on INPUT > + ---help--- > + This driver supports virtio input devices such as > + keyboards, mice and tablets. > + > + If unsure, say M. > + > config VIRTIO_MMIO > tristate "Platform bus driver for memory mapped virtio devices" > depends on HAS_IOMEM > diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile > index d85565b..41e30e3 100644 > --- a/drivers/virtio/Makefile > +++ b/drivers/virtio/Makefile > @@ -4,3 +4,4 @@ obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o > virtio_pci-y := virtio_pci_modern.o virtio_pci_common.o > virtio_pci-$(CONFIG_VIRTIO_PCI_LEGACY) += virtio_pci_legacy.o > obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o > +obj-$(CONFIG_VIRTIO_INPUT) += virtio_input.o > diff --git a/drivers/virtio/virtio_input.c b/drivers/virtio/virtio_input.c > new file mode 100644 > index 0000000..2d425cf > --- /dev/null > +++ b/drivers/virtio/virtio_input.c > @@ -0,0 +1,313 @@ > +#include <linux/module.h> > +#include <linux/virtio.h> > +#include <linux/input.h> > + > +#include <uapi/linux/virtio_ids.h> > +#include <uapi/linux/virtio_input.h> > + > +struct virtio_input { > + struct virtio_device *vdev; > + struct input_dev *idev; > + char name[64]; > + char serial[64]; > + char phys[64]; > + struct virtqueue *evt, *sts; > + struct virtio_input_event evts[64]; > +}; > + > +static ssize_t serial_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct input_dev *idev = to_input_dev(dev); > + struct virtio_input *vi = input_get_drvdata(idev); > + return sprintf(buf, "%s\n", vi->serial); > +} > +static DEVICE_ATTR_RO(serial); > + > +static struct attribute *dev_attrs[] = { > + &dev_attr_serial.attr, > + NULL > +}; > + > +static umode_t dev_attrs_are_visible(struct kobject *kobj, > + struct attribute *a, int n) > +{ > + struct device *dev = container_of(kobj, struct device, kobj); > + struct input_dev *idev = to_input_dev(dev); > + struct virtio_input *vi = input_get_drvdata(idev); > + > + if (a == &dev_attr_serial.attr && !strlen(vi->serial)) > + return 0; > + > + return a->mode; > +} > + > +static struct attribute_group dev_attr_grp = { > + .attrs = dev_attrs, > + .is_visible = dev_attrs_are_visible, > +}; > + > +static const struct attribute_group *dev_attr_groups[] = { > + &dev_attr_grp, > + NULL > +}; > + > +static void virtinput_queue_evtbuf(struct virtio_input *vi, > + struct virtio_input_event *evtbuf) > +{ > + struct scatterlist sg[1]; > + > + sg_init_one(sg, evtbuf, sizeof(*evtbuf)); > + virtqueue_add_inbuf(vi->evt, sg, 1, evtbuf, GFP_ATOMIC); > +} > + > +static void virtinput_recv_events(struct virtqueue *vq) > +{ > + struct virtio_input *vi = vq->vdev->priv; > + struct virtio_input_event *event; > + unsigned int len; > + > + while ((event = virtqueue_get_buf(vi->evt, &len)) != NULL) { > + input_event(vi->idev, > + le16_to_cpu(event->type), > + le16_to_cpu(event->code), > + le32_to_cpu(event->value)); > + virtinput_queue_evtbuf(vi, event); > + } > + virtqueue_kick(vq); > +} > + > +static int virtinput_send_status(struct virtio_input *vi, > + u16 type, u16 code, s32 value) > +{ > + struct virtio_input_event *stsbuf; > + struct scatterlist sg[1]; > + > + stsbuf = kzalloc(sizeof(*stsbuf), GFP_ATOMIC); > + if (!stsbuf) > + return -ENOMEM; > + > + stsbuf->type = cpu_to_le16(type); > + stsbuf->code = cpu_to_le16(code); > + stsbuf->value = cpu_to_le32(value); > + sg_init_one(sg, stsbuf, sizeof(*stsbuf)); > + virtqueue_add_outbuf(vi->sts, sg, 1, stsbuf, GFP_ATOMIC); > + virtqueue_kick(vi->sts);GFP_ATOMIC, eww. But everyone does that for input_event() callbacks.. we should fix that for user-space input one day.> + return 0; > +} > + > +static void virtinput_recv_status(struct virtqueue *vq) > +{ > + struct virtio_input *vi = vq->vdev->priv; > + struct virtio_input_event *stsbuf; > + unsigned int len; > + > + while ((stsbuf = virtqueue_get_buf(vi->sts, &len)) != NULL) > + kfree(stsbuf); > + virtqueue_kick(vq); > +} > + > +static int virtinput_status(struct input_dev *idev, unsigned int type, > + unsigned int code, int value) > +{ > + struct virtio_input *vi = input_get_drvdata(idev); > + > + return virtinput_send_status(vi, type, code, value); > +} > + > +static size_t virtinput_cfg_select(struct virtio_input *vi, > + u8 select, u8 subsel) > +{ > + u8 size; > + > + virtio_cwrite(vi->vdev, struct virtio_input_config, select, &select); > + virtio_cwrite(vi->vdev, struct virtio_input_config, subsel, &subsel); > + virtio_cread(vi->vdev, struct virtio_input_config, size, &size); > + return size; > +} > + > +static void virtinput_cfg_bits(struct virtio_input *vi, int select, int subsel, > + unsigned long *bits, unsigned int bitcount) > +{ > + unsigned int bit; > + size_t bytes; > + u8 cfg = 0; > + > + bytes = virtinput_cfg_select(vi, select, subsel); > + if (!bytes) > + return; > + if (bitcount > bytes*8) > + bitcount = bytes*8; > + if (select == VIRTIO_INPUT_CFG_EV_BITS) > + set_bit(subsel, vi->idev->evbit); > + for (bit = 0; bit < bitcount; bit++) { > + if ((bit % 8) == 0) > + virtio_cread(vi->vdev, struct virtio_input_config, > + u.bitmap[bit/8], &cfg); > + if (cfg & (1 << (bit % 8))) > + set_bit(bit, bits); > + } > +} > + > +static void virtinput_cfg_abs(struct virtio_input *vi, int abs) > +{ > + u32 size, mi, ma, fu, fl; > + > + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ABS_INFO, abs); > + virtio_cread(vi->vdev, struct virtio_input_config, u.abs.min, &mi); > + virtio_cread(vi->vdev, struct virtio_input_config, u.abs.max, &ma); > + virtio_cread(vi->vdev, struct virtio_input_config, u.abs.fuzz, &fu); > + virtio_cread(vi->vdev, struct virtio_input_config, u.abs.flat, &fl);abs.resolution is missing. Please add it, we really also need to add it to uinput one day.> + input_set_abs_params(vi->idev, abs, > + le32_to_cpu(mi), le32_to_cpu(ma), > + le32_to_cpu(fu), le32_to_cpu(fl)); > +} > + > +static int virtinput_init_vqs(struct virtio_input *vi) > +{ > + struct virtqueue *vqs[2]; > + vq_callback_t *cbs[] = { virtinput_recv_events, > + virtinput_recv_status }; > + const char *names[] = { "events", "status" }; > + int i, err, size; > + > + err = vi->vdev->config->find_vqs(vi->vdev, 2, vqs, cbs, names); > + if (err) > + return err; > + vi->evt = vqs[0]; > + vi->sts = vqs[1]; > + > + size = virtqueue_get_vring_size(vi->evt); > + if (size > ARRAY_SIZE(vi->evts)) > + size = ARRAY_SIZE(vi->evts); > + for (i = 0; i < size; i++) > + virtinput_queue_evtbuf(vi, &vi->evts[i]); > + > + return 0; > +} > + > +static int virtinput_probe(struct virtio_device *vdev) > +{ > + struct virtio_input *vi; > + size_t size; > + int abs, err; > + > + vi = kzalloc(sizeof(*vi), GFP_KERNEL); > + if (!vi) { > + err = -ENOMEM; > + goto out1; > + } > + vdev->priv = vi; > + vi->vdev = vdev; > + > + err = virtinput_init_vqs(vi); > + if (err) > + goto out2; > + > + vi->idev = input_allocate_device(); > + if (!vi->idev) { > + err = -ENOMEM; > + goto out3; > + } > + input_set_drvdata(vi->idev, vi); > + > + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_NAME, 0); > + virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, u), > + vi->name, min(size, sizeof(vi->name))); > + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_ID_SERIAL, 0); > + virtio_cread_bytes(vi->vdev, offsetof(struct virtio_input_config, u), > + vi->serial, min(size, sizeof(vi->serial))); > + snprintf(vi->phys, sizeof(vi->phys), > + "virtio%d/input0", vdev->index); > + > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_PROP_BITS, 0, > + vi->idev->propbit, INPUT_PROP_CNT); > + size = virtinput_cfg_select(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REP); > + if (size) > + set_bit(EV_REP, vi->idev->evbit); > + > + vi->idev->name = vi->name; > + vi->idev->phys = vi->phys;Can you set vi->idev->uniq to the virtio-bus path?> + vi->idev->id.bustype = BUS_VIRTUAL; > + vi->idev->id.vendor = 0x0001; > + vi->idev->id.product = 0x0001; > + vi->idev->id.version = 0x0100;Please don't hardcode those. All user-space based interaction with input-devices relies on those IDs. Can we retrieve it from the host just like the name?> + vi->idev->dev.parent = &vdev->dev; > + vi->idev->dev.groups = dev_attr_groups; > + vi->idev->event = virtinput_status; > + > + /* device -> kernel */ > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_KEY, > + vi->idev->keybit, KEY_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_REL, > + vi->idev->relbit, REL_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_ABS, > + vi->idev->absbit, ABS_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_MSC, > + vi->idev->mscbit, MSC_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SW, > + vi->idev->swbit, SW_CNT); > + > + /* kernel -> device */ > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_LED, > + vi->idev->ledbit, LED_CNT); > + virtinput_cfg_bits(vi, VIRTIO_INPUT_CFG_EV_BITS, EV_SND, > + vi->idev->sndbit, SND_CNT); > + > + if (test_bit(EV_ABS, vi->idev->evbit)) { > + for (abs = 0; abs < ABS_CNT; abs++) { > + if (!test_bit(abs, vi->idev->absbit)) > + continue; > + virtinput_cfg_abs(vi, abs); > + } > + } > + > + err = input_register_device(vi->idev); > + if (err) > + goto out4; > + > + return 0; > + > +out4: > + input_free_device(vi->idev); > +out3: > + vdev->config->del_vqs(vdev); > +out2: > + kfree(vi); > +out1: > + return err; > +} > + > +static void virtinput_remove(struct virtio_device *vdev) > +{ > + struct virtio_input *vi = vdev->priv; > + > + input_unregister_device(vi->idev); > + vdev->config->reset(vdev); > + vdev->config->del_vqs(vdev); > + kfree(vi); > +} > + > +static unsigned int features[] = { > +}; > +static struct virtio_device_id id_table[] = { > + { VIRTIO_ID_INPUT, VIRTIO_DEV_ANY_ID }, > + { 0 }, > +}; > + > +static struct virtio_driver virtio_input_driver = { > + .driver.name = KBUILD_MODNAME, > + .driver.owner = THIS_MODULE, > + .feature_table = features, > + .feature_table_size = ARRAY_SIZE(features), > + .id_table = id_table, > + .probe = virtinput_probe, > + .remove = virtinput_remove, > +}; > + > +module_virtio_driver(virtio_input_driver); > +MODULE_DEVICE_TABLE(virtio, id_table); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Virtio input device driver"); > +MODULE_AUTHOR("Gerd Hoffmann <kraxel at redhat.com>"); > diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h > index 284fc3a..5f60aa4 100644 > --- a/include/uapi/linux/virtio_ids.h > +++ b/include/uapi/linux/virtio_ids.h > @@ -39,5 +39,6 @@ > #define VIRTIO_ID_9P 9 /* 9p virtio console */ > #define VIRTIO_ID_RPROC_SERIAL 11 /* virtio remoteproc serial link */ > #define VIRTIO_ID_CAIF 12 /* Virtio caif */ > +#define VIRTIO_ID_INPUT 18 /* virtio input */ > > #endif /* _LINUX_VIRTIO_IDS_H */ > diff --git a/include/uapi/linux/virtio_input.h b/include/uapi/linux/virtio_input.h > new file mode 100644 > index 0000000..190d04a > --- /dev/null > +++ b/include/uapi/linux/virtio_input.h > @@ -0,0 +1,65 @@ > +#ifndef _LINUX_VIRTIO_INPUT_H > +#define _LINUX_VIRTIO_INPUT_H > +/* This header is BSD licensed so anyone can use the definitions to implement > + * compatible drivers/servers. > + * > + * Redistribution and use in source and binary forms, with or without > + * modification, are permitted provided that the following conditions > + * are met: > + * 1. Redistributions of source code must retain the above copyright > + * notice, this list of conditions and the following disclaimer. > + * 2. Redistributions in binary form must reproduce the above copyright > + * notice, this list of conditions and the following disclaimer in the > + * documentation and/or other materials provided with the distribution. > + * 3. Neither the name of IBM nor the names of its contributors > + * may be used to endorse or promote products derived from this software > + * without specific prior written permission. > + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND > + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE > + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE > + * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE > + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL > + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS > + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) > + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT > + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY > + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF > + * SUCH DAMAGE. */ > +#include <linux/virtio_ids.h> > +#include <linux/virtio_config.h> > + > +enum virtio_input_config_select { > + VIRTIO_INPUT_CFG_UNSET = 0x00, > + VIRTIO_INPUT_CFG_ID_NAME = 0x01, > + VIRTIO_INPUT_CFG_ID_SERIAL = 0x02, > + VIRTIO_INPUT_CFG_PROP_BITS = 0x10, > + VIRTIO_INPUT_CFG_EV_BITS = 0x11, > + VIRTIO_INPUT_CFG_ABS_INFO = 0x12, > +}; > + > +struct virtio_input_absinfo { > + __le32 min; > + __le32 max; > + __le32 fuzz; > + __le32 flat; > +}; > + > +struct virtio_input_config { > + __u8 select; > + __u8 subsel; > + __u8 size; > + __u8 reserved; > + union { > + char string[128]; > + __u8 bitmap[128]; > + struct virtio_input_absinfo abs; > + } u; > +}; > + > +struct virtio_input_event { > + __le16 type; > + __le16 code; > + __le32 value; > +}; > + > +#endif /* _LINUX_VIRTIO_INPUT_H */ > --The input-parts look good to me (apart from my comments). No idea how virtio exactly works, so I'll leave that to Rusty. I put Dmitry on CC, he might have some more valuable input on the input-parts. Thanks David
On Thu, Mar 19, 2015 at 10:13:10AM +0100, Gerd Hoffmann wrote:> Hi, > > This patch adds a virtio driver for input devices. > > Specification: > https://www.kraxel.org/cgit/virtio-spec/log/?h=virtio-input > https://www.kraxel.org/virtio/virtio-v1.0-csprd03-virtio-input.html#x1-2640007OK, I don't know which thread should I use for spec discussions. Referring to that: "See file:///usr/include/linux/input.h." Is likely not present on many systems, or might not include the info you refer to. "type, code and value are filled according to the linux input layer (evdev) interface" Which version? How will non-linux guests know what to implement?> > Qemu patches; > https://lists.gnu.org/archive/html/qemu-devel/2015-03/threads.html#03973 > > Gerd Hoffmann (1): > Add virtio-input driver. > > drivers/virtio/Kconfig | 10 ++ > drivers/virtio/Makefile | 1 + > drivers/virtio/virtio_input.c | 313 ++++++++++++++++++++++++++++++++++++++ > include/uapi/linux/virtio_ids.h | 1 + > include/uapi/linux/virtio_input.h | 65 ++++++++ > 5 files changed, 390 insertions(+) > create mode 100644 drivers/virtio/virtio_input.c > create mode 100644 include/uapi/linux/virtio_input.h > > -- > 1.8.3.1
On Do, 2015-03-19 at 14:35 +0100, Michael S. Tsirkin wrote:> On Thu, Mar 19, 2015 at 10:13:10AM +0100, Gerd Hoffmann wrote: > > Hi, > > > > This patch adds a virtio driver for input devices. > > > > Specification: > > https://www.kraxel.org/cgit/virtio-spec/log/?h=virtio-input > > https://www.kraxel.org/virtio/virtio-v1.0-csprd03-virtio-input.html#x1-2640007 > > > OK, I don't know which thread should I use for spec discussions. > Referring to that: > > "See file:///usr/include/linux/input.h." > > Is likely not present on many systems, or might not include > the info you refer to.Dunno what the best way to deal with it is. Link to the version online @ kernel.org instead maybe?> "type, code and value are filled according to the linux input layer > (evdev) interface" > > Which version?Latest. As far I know there never ever have been incompatible changes to the interface, and given this is userspace/kernel abi I don't expect that to happen in the future.> How will non-linux guests know what to implement?There are some docs on the linux input layer and evdev events in Documentation/input/ in the kernel tree. cheers, Gerd