Hi K.Y.,

On Tue, Sep 17, 2013 at 04:26:58PM -0700, K. Y. Srinivasan wrote:
> Add a new driver to support synthetic keyboard. On the next generation
> Hyper-V guest firmware, many legacy devices will not be emulated and this
> driver will be required.
> 
> I would like to thank Vojtech Pavlik <vojt...@suse.cz> for helping me with the
> details of the AT keyboard driver. I would also like to thank
> Dan Carpenter <dan.carpen...@oracle.com> and
> Dmitry Torokhov <dmitry.torok...@gmail.com> for their detailed review of this
> driver.
> 
> I have addressed all the comments of Dan and Dmitry in this version of
> the patch

This looks much better. Could you tell me if the patch below (on top of
yours) still works?

Thanks.

-- 
Dmitry

Input: hyperv-keyboard - misc changes

From: Dmitry Torokhov <dmitry.torok...@gmail.com>

Signed-off-by: Dmitry Torokhov <dmitry.torok...@gmail.com>
---
 drivers/input/serio/Kconfig           |    3 
 drivers/input/serio/hyperv-keyboard.c |  378 ++++++++++++++++++---------------
 2 files changed, 208 insertions(+), 173 deletions(-)

diff --git a/drivers/input/serio/Kconfig b/drivers/input/serio/Kconfig
index f3996e7..a5f342e 100644
--- a/drivers/input/serio/Kconfig
+++ b/drivers/input/serio/Kconfig
@@ -274,4 +274,7 @@ config HYPERV_KEYBOARD
        help
          Select this option to enable the Hyper-V Keyboard driver.
 
+         To compile this driver as a module, choose M here: the module will
+         be called hyperv_keyboard.
+
 endif
diff --git a/drivers/input/serio/hyperv-keyboard.c 
b/drivers/input/serio/hyperv-keyboard.c
index c327a18..401fbdd 100644
--- a/drivers/input/serio/hyperv-keyboard.c
+++ b/drivers/input/serio/hyperv-keyboard.c
@@ -10,6 +10,7 @@
  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  *  more details.
  */
+
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/device.h>
@@ -42,20 +43,16 @@ enum synth_kbd_msg_type {
  * Basic message structures.
  */
 struct synth_kbd_msg_hdr {
-       u32 type;
+       __le32 type;
 };
 
 struct synth_kbd_msg {
        struct synth_kbd_msg_hdr header;
-       char data[1]; /* Enclosed message */
+       char data[]; /* Enclosed message */
 };
 
 union synth_kbd_version {
-       struct {
-               u16 minor_version;
-               u16 major_version;
-       };
-       u32 version;
+       __le32 version;
 };
 
 /*
@@ -78,8 +75,8 @@ struct synth_kbd_protocol_response {
 #define IS_E1          BIT(3)
 struct synth_kbd_keystroke {
        struct synth_kbd_msg_hdr header;
-       u16 make_code;
-       u16 reserved0;
+       __le16 make_code;
+       __le16 reserved0;
        __le32 info; /* Additional information */
 };
 
@@ -98,58 +95,27 @@ struct synth_kbd_keystroke {
  * Represents a keyboard device
  */
 struct hv_kbd_dev {
-       struct hv_device        *device;
+       struct hv_device *hv_dev;
+       struct serio *hv_serio;
        struct synth_kbd_protocol_request protocol_req;
        struct synth_kbd_protocol_response protocol_resp;
        /* Synchronize the request/response if needed */
-       struct completion       wait_event;
-       struct serio            *hv_serio;
+       struct completion wait_event;
+       spinlock_t lock; /* protects 'started' field */
+       bool started;
 };
 
-
-static struct hv_kbd_dev *hv_kbd_alloc_device(struct hv_device *device)
-{
-       struct hv_kbd_dev *kbd_dev;
-       struct serio *hv_serio;
-
-       kbd_dev = kzalloc(sizeof(struct hv_kbd_dev), GFP_KERNEL);
-       if (!kbd_dev)
-               return NULL;
-       hv_serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
-       if (hv_serio == NULL) {
-               kfree(kbd_dev);
-               return NULL;
-       }
-       hv_serio->id.type = SERIO_8042_XL;
-       strlcpy(hv_serio->name, dev_name(&device->device),
-               sizeof(hv_serio->name));
-       strlcpy(hv_serio->phys, dev_name(&device->device),
-               sizeof(hv_serio->phys));
-       hv_serio->dev.parent  = &device->device;
-       kbd_dev->device = device;
-       kbd_dev->hv_serio = hv_serio;
-       hv_set_drvdata(device, kbd_dev);
-       init_completion(&kbd_dev->wait_event);
-
-       return kbd_dev;
-}
-
-static void hv_kbd_free_device(struct hv_kbd_dev *device)
-{
-       serio_unregister_port(device->hv_serio);
-       hv_set_drvdata(device->device, NULL);
-       kfree(device);
-}
-
-static void hv_kbd_on_receive(struct hv_device *device,
-                               struct synth_kbd_msg *msg, u32 msg_length)
+static void hv_kbd_on_receive(struct hv_device *hv_dev,
+                             struct synth_kbd_msg *msg, u32 msg_length)
 {
-       struct hv_kbd_dev *kbd_dev = hv_get_drvdata(device);
+       struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
        struct synth_kbd_keystroke *ks_msg;
-       u16 scan_code;
+       unsigned long flags;
+       u32 msg_type = __le32_to_cpu(msg->header.type);
        u32 info;
+       u16 scan_code;
 
-       switch (msg->header.type) {
+       switch (msg_type) {
        case SYNTH_KBD_PROTOCOL_RESPONSE:
                /*
                 * Validate the information provided by the host.
@@ -158,13 +124,17 @@ static void hv_kbd_on_receive(struct hv_device *device,
                 * goes away).
                 */
                if (msg_length < sizeof(struct synth_kbd_protocol_response)) {
-                       pr_err("Illegal protocol response packet\n");
+                       dev_err(&hv_dev->device,
+                               "Illegal protocol response packet (len: %d)\n",
+                               msg_length);
                        break;
                }
+
                memcpy(&kbd_dev->protocol_resp, msg,
                        sizeof(struct synth_kbd_protocol_response));
                complete(&kbd_dev->wait_event);
                break;
+
        case SYNTH_KBD_EVENT:
                /*
                 * Validate the information provided by the host.
@@ -173,105 +143,122 @@ static void hv_kbd_on_receive(struct hv_device *device,
                 * goes away).
                 */
                if (msg_length < sizeof(struct  synth_kbd_keystroke)) {
-                       pr_err("Illegal keyboard event  packet\n");
+                       dev_err(&hv_dev->device,
+                               "Illegal keyboard event packet (len: %d)\n",
+                               msg_length);
                        break;
                }
+
                ks_msg = (struct synth_kbd_keystroke *)msg;
-               scan_code = ks_msg->make_code;
                info = __le32_to_cpu(ks_msg->info);
 
                /*
                 * Inject the information through the serio interrupt.
                 */
-               if (info & IS_E0)
-                       serio_interrupt(kbd_dev->hv_serio, XTKBD_EMUL0, 0);
-               serio_interrupt(kbd_dev->hv_serio,
-                               scan_code | ((info & IS_BREAK) ?
-                               XTKBD_RELEASE : 0),
-                               0);
+               spin_lock_irqsave(&kbd_dev->lock, flags);
+               if (kbd_dev->started) {
+                       if (info & IS_E0)
+                               serio_interrupt(kbd_dev->hv_serio,
+                                               XTKBD_EMUL0, 0);
+
+                       scan_code = __le16_to_cpu(ks_msg->make_code);
+                       if (info & IS_BREAK)
+                               scan_code |= XTKBD_RELEASE;
+
+                       serio_interrupt(kbd_dev->hv_serio, scan_code, 0);
+               }
+               spin_unlock_irqrestore(&kbd_dev->lock, flags);
+               break;
+
+       default:
+               dev_err(&hv_dev->device,
+                       "unhandled message type %d\n", msg_type);
+       }
+}
+
+static void hv_kbd_handle_received_packet(struct hv_device *hv_dev,
+                                         struct vmpacket_descriptor *desc,
+                                         u32 bytes_recvd,
+                                         u64 req_id)
+{
+       struct synth_kbd_msg *msg;
+       u32 msg_sz;
+
+       switch (desc->type) {
+       case VM_PKT_COMP:
+               break;
+
+       case VM_PKT_DATA_INBAND:
+               /*
+                * We have a packet that has "inband" data. The API used
+                * for retrieving the packet guarantees that the complete
+                * packet is read. So, minimally, we should be able to
+                * parse the payload header safely (assuming that the host
+                * can be trusted.  Trusting the host seems to be a
+                * reasonable assumption because in a virtualized
+                * environment there is not whole lot you can do if you
+                * don't trust the host.
+                *
+                * Nonetheless, let us validate if the host can be trusted
+                * (in a trivial way).  The interesting aspect of this
+                * validation is how do you recover if we discover that the
+                * host is not to be trusted? Simply dropping the packet, I
+                * don't think is an appropriate recovery.  In the interest
+                * of failing fast, it may be better to crash the guest.
+                * For now, I will just drop the packet!
+                */
+
+               msg_sz = bytes_recvd - (desc->offset8 << 3);
+               if (msg_sz <= sizeof(struct synth_kbd_msg_hdr)) {
+                       /*
+                        * Drop the packet and hope
+                        * the problem magically goes away.
+                        */
+                       dev_err(&hv_dev->device,
+                               "Illegal packet (type: %d, tid: %llx, size: 
%d)\n",
+                               desc->type, req_id, msg_sz);
+                       break;
+               }
+
+               msg = (void *)desc + (desc->offset8 << 3);
+               hv_kbd_on_receive(hv_dev, msg, msg_sz);
                break;
+
        default:
-               pr_err("unhandled message type %d\n", msg->header.type);
+               dev_err(&hv_dev->device,
+                       "unhandled packet type %d, tid %llx len %d\n",
+                       desc->type, req_id, bytes_recvd);
+               break;
        }
 }
 
 static void hv_kbd_on_channel_callback(void *context)
 {
-       const int packet_size = 0x100;
-       int ret;
-       struct hv_device *device = context;
+       struct hv_device *hv_dev = context;
+       void *buffer;
+       int bufferlen = 0x100; /* Start with sensible size */
        u32 bytes_recvd;
        u64 req_id;
-       struct vmpacket_descriptor *desc;
-       struct synth_kbd_msg *msg;
-       int hdr_sz = sizeof(struct synth_kbd_msg);
-       int msg_sz;
-       unsigned char   *buffer;
-       int     bufferlen = packet_size;
+       int error;
 
        buffer = kmalloc(bufferlen, GFP_ATOMIC);
        if (!buffer)
                return;
 
        while (1) {
-               ret = vmbus_recvpacket_raw(device->channel, buffer,
-                                       bufferlen, &bytes_recvd, &req_id);
-
-               switch (ret) {
+               error = vmbus_recvpacket_raw(hv_dev->channel, buffer, bufferlen,
+                                            &bytes_recvd, &req_id);
+               switch (error) {
                case 0:
                        if (bytes_recvd == 0) {
                                kfree(buffer);
                                return;
                        }
-                       desc = (struct vmpacket_descriptor *)buffer;
-                       switch (desc->type) {
-                       case VM_PKT_COMP:
-                               break;
-                       case VM_PKT_DATA_INBAND:
-                               /*
-                                * We have a packet that has "inband"
-                                * data. The API used for retrieving the
-                                * packet guarantees that the complete
-                                * packet is read. So, minimally, we should
-                                * be able to parse the payload header
-                                * safely (assuming that the host can be
-                                * trusted. Trusting the host seems to be a
-                                * reasonable assumption because in a
-                                * virtualized environment there is not whole
-                                * lot you can do if you don't trust the host.
-                                *
-                                * Nonetheless, let us validate if the host can
-                                * be trusted (in a trivial way).
-                                * The intresting aspect of this
-                                * validation is how do you recover if we
-                                * discover that the host is not to be
-                                * trusted? Simply dropping the packet, I
-                                * don't think is an appropriate recovery.
-                                * In the interest of failing fast, it may
-                                * be better to crash the guest. For now,
-                                * I will just drop the packet!
-                                */
-                               msg_sz = bytes_recvd - (desc->offset8 << 3);
-                               if (msg_sz < hdr_sz) {
-                                       /*
-                                        * Drop the packet and hope
-                                        * the problem magically goes away.
-                                        */
-                                       pr_err("Illegal packet\n");
-                                       break;
-                               }
-
-                               msg = (struct synth_kbd_msg *)
-                                       ((unsigned long)desc +
-                                       (desc->offset8 << 3));
-                               hv_kbd_on_receive(device, msg, (u32)msg_sz);
-                               break;
-                       default:
-                               pr_err("unhandled packet type %d, tid %llx len 
%d\n",
-                                       desc->type, req_id, bytes_recvd);
-                               break;
-                       }
+
+                       hv_kbd_handle_received_packet(hv_dev, buffer,
+                                                     bytes_recvd, req_id);
                        break;
+
                case -ENOBUFS:
                        kfree(buffer);
                        /* Handle large packet */
@@ -284,83 +271,128 @@ static void hv_kbd_on_channel_callback(void *context)
        }
 }
 
-static int hv_kbd_connect_to_vsp(struct hv_device *device)
+static int hv_kbd_connect_to_vsp(struct hv_device *hv_dev)
 {
-       int ret;
-       int t;
-       u32 proto_status;
-       struct hv_kbd_dev *kbd_dev = hv_get_drvdata(device);
+       struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
        struct synth_kbd_protocol_request *request;
        struct synth_kbd_protocol_response *response;
+       u32 proto_status;
+       int error;
 
        request = &kbd_dev->protocol_req;
        memset(request, 0, sizeof(struct synth_kbd_protocol_request));
-       request->header.type = SYNTH_KBD_PROTOCOL_REQUEST;
-       request->version_requested.version = SYNTH_KBD_VERSION;
-
-       ret = vmbus_sendpacket(device->channel, request,
-                               sizeof(struct synth_kbd_protocol_request),
-                               (unsigned long)request,
-                               VM_PKT_DATA_INBAND,
-                               VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
-       if (ret)
-               return ret;
-
-       t = wait_for_completion_timeout(&kbd_dev->wait_event, 10 * HZ);
-       if (!t)
+       request->header.type = cpu_to_le32(SYNTH_KBD_PROTOCOL_REQUEST);
+       request->version_requested.version = cpu_to_le32(SYNTH_KBD_VERSION);
+
+       error = vmbus_sendpacket(hv_dev->channel, request,
+                                sizeof(struct synth_kbd_protocol_request),
+                                (unsigned long)request,
+                                VM_PKT_DATA_INBAND,
+                                VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
+       if (error)
+               return error;
+
+       if (!wait_for_completion_timeout(&kbd_dev->wait_event, 10 * HZ))
                return -ETIMEDOUT;
 
        response = &kbd_dev->protocol_resp;
        proto_status = __le32_to_cpu(response->proto_status);
        if (!(proto_status & PROTOCOL_ACCEPTED)) {
-               pr_err("synth_kbd protocol request failed (version %d)\n",
-                      SYNTH_KBD_VERSION);
+               dev_err(&hv_dev->device,
+                       "synth_kbd protocol request failed (version %d)\n",
+                       SYNTH_KBD_VERSION);
                return -ENODEV;
        }
+
+       return 0;
+}
+
+static int hv_kbd_start(struct serio *serio)
+{
+       struct hv_kbd_dev *kbd_dev = serio->port_data;
+       unsigned long flags;
+
+       spin_lock_irqsave(&kbd_dev->lock, flags);
+       kbd_dev->started = true;
+       spin_unlock_irqrestore(&kbd_dev->lock, flags);
+
        return 0;
 }
 
-static int hv_kbd_probe(struct hv_device *device,
+static void hv_kbd_stop(struct serio *serio)
+{
+       struct hv_kbd_dev *kbd_dev = serio->port_data;
+       unsigned long flags;
+
+       spin_lock_irqsave(&kbd_dev->lock, flags);
+       kbd_dev->started = false;
+       spin_unlock_irqrestore(&kbd_dev->lock, flags);
+}
+
+static int hv_kbd_probe(struct hv_device *hv_dev,
                        const struct hv_vmbus_device_id *dev_id)
 {
-       int ret;
        struct hv_kbd_dev *kbd_dev;
+       struct serio *hv_serio;
+       int error;
 
-       kbd_dev = hv_kbd_alloc_device(device);
-       if (!kbd_dev)
-               return -ENOMEM;
-       ret = vmbus_open(device->channel,
-               KBD_VSC_SEND_RING_BUFFER_SIZE,
-               KBD_VSC_RECV_RING_BUFFER_SIZE,
-               NULL,
-               0,
-               hv_kbd_on_channel_callback,
-               device
-               );
-
-       if (ret)
-               goto probe_open_err;
-       ret = hv_kbd_connect_to_vsp(device);
-       if (ret)
-               goto probe_connect_err;
-       serio_register_port(kbd_dev->hv_serio);
-       return ret;
+       kbd_dev = kzalloc(sizeof(struct hv_kbd_dev), GFP_KERNEL);
+       hv_serio = kzalloc(sizeof(struct serio), GFP_KERNEL);
+       if (!kbd_dev || !hv_serio) {
+               error = -ENOMEM;
+               goto err_free_mem;
+       }
 
-probe_connect_err:
-       vmbus_close(device->channel);
+       kbd_dev->hv_dev = hv_dev;
+       kbd_dev->hv_serio = hv_serio;
+       spin_lock_init(&kbd_dev->lock);
+       init_completion(&kbd_dev->wait_event);
+       hv_set_drvdata(hv_dev, kbd_dev);
 
-probe_open_err:
-       hv_kbd_free_device(kbd_dev);
+       hv_serio->dev.parent  = &hv_dev->device;
+       hv_serio->id.type = SERIO_8042_XL;
+       strlcpy(hv_serio->name, dev_name(&hv_dev->device),
+               sizeof(hv_serio->name));
+       strlcpy(hv_serio->phys, dev_name(&hv_dev->device),
+               sizeof(hv_serio->phys));
+
+       hv_serio->start = hv_kbd_start;
+       hv_serio->stop = hv_kbd_stop;
+
+       error = vmbus_open(hv_dev->channel,
+                          KBD_VSC_SEND_RING_BUFFER_SIZE,
+                          KBD_VSC_RECV_RING_BUFFER_SIZE,
+                          NULL, 0,
+                          hv_kbd_on_channel_callback,
+                          hv_dev);
+       if (error)
+               goto err_free_mem;
+
+       error = hv_kbd_connect_to_vsp(hv_dev);
+       if (error)
+               goto err_close_vmbus;
 
-       return ret;
+       serio_register_port(kbd_dev->hv_serio);
+       return 0;
+
+err_close_vmbus:
+       vmbus_close(hv_dev->channel);
+err_free_mem:
+       kfree(hv_serio);
+       kfree(kbd_dev);
+       return error;
 }
 
-static int hv_kbd_remove(struct hv_device *dev)
+static int hv_kbd_remove(struct hv_device *hv_dev)
 {
-       struct hv_kbd_dev *kbd_dev = hv_get_drvdata(dev);
+       struct hv_kbd_dev *kbd_dev = hv_get_drvdata(hv_dev);
+
+       serio_unregister_port(kbd_dev->hv_serio);
+       vmbus_close(hv_dev->channel);
+       kfree(kbd_dev);
+
+       hv_set_drvdata(hv_dev, NULL);
 
-       vmbus_close(dev->channel);
-       hv_kbd_free_device(kbd_dev);
        return 0;
 }
 
_______________________________________________
devel mailing list
de...@linuxdriverproject.org
http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel

Reply via email to