staging/mei: propagate error codes up in the write flow

Change mei_write_message's return type from bool to int
to enable propagation of the error code up to caller functions.
The function now returns -EIO when low level write fails and 0
on success.
A similar change is done in intermediate caller functions:
mei_send_flow_control, mei_connect, and mei_disconnect

This makes code more alike to typical Linux kernel error
handling.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/mei/init.c b/drivers/staging/mei/init.c
index e24b6ad..eab711f 100644 (file)
--- a/drivers/staging/mei/init.c
+++ b/drivers/staging/mei/init.c
@@ -366,7 +366,7 @@ void mei_host_start_message(struct mei_device *dev)
        host_start_req->host_version.major_version = HBM_MAJOR_VERSION;
        host_start_req->host_version.minor_version = HBM_MINOR_VERSION;
        dev->recvd_msg = false;
-       if (!mei_write_message(dev, mei_hdr, (unsigned char *)host_start_req,
+       if (mei_write_message(dev, mei_hdr, (unsigned char *)host_start_req,
                                       mei_hdr->length)) {
                dev_dbg(&dev->pdev->dev, "write send version message to FW fail.\n");
                dev->mei_state = MEI_RESETING;
@@ -399,7 +399,7 @@ void mei_host_enum_clients_message(struct mei_device *dev)
        host_enum_req = (struct hbm_host_enum_request *) &dev->wr_msg_buf[1];
        memset(host_enum_req, 0, sizeof(struct hbm_host_enum_request));
        host_enum_req->hbm_cmd = HOST_ENUM_REQ_CMD;
-       if (!mei_write_message(dev, mei_hdr, (unsigned char *)host_enum_req,
+       if (mei_write_message(dev, mei_hdr, (unsigned char *)host_enum_req,
                                mei_hdr->length)) {
                dev->mei_state = MEI_RESETING;
                dev_dbg(&dev->pdev->dev, "write send enumeration request message to FW fail.\n");
@@ -407,7 +407,7 @@ void mei_host_enum_clients_message(struct mei_device *dev)
        }
        dev->init_clients_state = MEI_ENUM_CLIENTS_MESSAGE;
        dev->init_clients_timer = INIT_CLIENTS_TIMEOUT;
-       return ;
+       return;
 }
 
 
@@ -485,7 +485,7 @@ int mei_host_client_properties(struct mei_device *dev)
                host_cli_req->hbm_cmd = HOST_CLIENT_PROPERTIES_REQ_CMD;
                host_cli_req->address = b;
 
-               if (!mei_write_message(dev, mei_header,
+               if (mei_write_message(dev, mei_header,
                                (unsigned char *)host_cli_req,
                                mei_header->length)) {
                        dev->mei_state = MEI_RESETING;
@@ -608,7 +608,7 @@ void mei_host_init_iamthif(struct mei_device *dev)
 
        dev->iamthif_msg_buf = msg_buf;
 
-       if (!mei_connect(dev, &dev->iamthif_cl)) {
+       if (mei_connect(dev, &dev->iamthif_cl)) {
                dev_dbg(&dev->pdev->dev, "Failed to connect to AMTHI client\n");
                dev->iamthif_cl.state = MEI_FILE_DISCONNECTED;
                dev->iamthif_cl.host_client_id = 0;
@@ -670,14 +670,12 @@ int mei_disconnect_host_client(struct mei_device *dev, struct mei_cl *cl)
        if (dev->mei_host_buffer_is_empty) {
                dev->mei_host_buffer_is_empty = false;
                if (mei_disconnect(dev, cl)) {
-                       mdelay(10); /* Wait for hardware disconnection ready */
-                       list_add_tail(&cb->cb_list,
-                               &dev->ctrl_rd_list.mei_cb.cb_list);
-               } else {
                        rets = -ENODEV;
                        dev_dbg(&dev->pdev->dev, "failed to call mei_disconnect.\n");
                        goto free;
                }
+               mdelay(10); /* Wait for hardware disconnection ready */
+               list_add_tail(&cb->cb_list, &dev->ctrl_rd_list.mei_cb.cb_list);
        } else {
                dev_dbg(&dev->pdev->dev, "add disconnect cb to control write list\n");
                list_add_tail(&cb->cb_list,

diff --git a/drivers/staging/mei/interface.c b/drivers/staging/mei/interface.c
index 8a80e80..9a2cfaf 100644 (file)
--- a/drivers/staging/mei/interface.c
+++ b/drivers/staging/mei/interface.c
@@ -125,7 +125,7 @@ int mei_count_empty_write_slots(struct mei_device *dev)
  * @write_buffer: message buffer will be written
  * @write_length: message size will be written
  *
- * returns 1 if success, 0 - otherwise.
+ * This function returns -EIO if write has failed
  */
 int mei_write_message(struct mei_device *dev,
                      struct mei_msg_hdr *header,
@@ -157,7 +157,7 @@ int mei_write_message(struct mei_device *dev,
        dw_to_write = ((write_length + 3) / 4);
 
        if (dw_to_write > empty_slots)
-               return 0;
+               return -EIO;
 
        mei_reg_write(dev, H_CB_WW, *((u32 *) header));
 
@@ -177,9 +177,9 @@ int mei_write_message(struct mei_device *dev,
        mei_hcsr_set(dev);
        dev->me_hw_state = mei_mecsr_read(dev);
        if ((dev->me_hw_state & ME_RDY_HRA) != ME_RDY_HRA)
-               return 0;
+               return -EIO;
 
-       return 1;
+       return 0;
 }
 
 /**
@@ -308,7 +308,7 @@ int mei_flow_ctrl_reduce(struct mei_device *dev, struct mei_cl *cl)
  * @dev: the device structure
  * @cl: private data of the file object
  *
- * returns 1 if success, 0 - otherwise.
+ * This function returns -EIO on write failure
  */
 int mei_send_flow_control(struct mei_device *dev, struct mei_cl *cl)
 {
@@ -330,14 +330,11 @@ int mei_send_flow_control(struct mei_device *dev, struct mei_cl *cl)
        memset(mei_flow_control->reserved, 0,
                        sizeof(mei_flow_control->reserved));
        dev_dbg(&dev->pdev->dev, "sending flow control host client = %d, ME client = %d\n",
-           cl->host_client_id, cl->me_client_id);
-       if (!mei_write_message(dev, mei_hdr,
-                               (unsigned char *) mei_flow_control,
-                               sizeof(struct hbm_flow_control)))
-               return 0;
-
-       return 1;
+               cl->host_client_id, cl->me_client_id);
 
+       return mei_write_message(dev, mei_hdr,
+                               (unsigned char *) mei_flow_control,
+                               sizeof(struct hbm_flow_control));
 }
 
 /**
@@ -371,7 +368,7 @@ int mei_other_client_is_connecting(struct mei_device *dev,
  * @dev: the device structure
  * @cl: private data of the file object
  *
- * returns 1 if success, 0 - otherwise.
+ * This function returns -EIO on write failure
  */
 int mei_disconnect(struct mei_device *dev, struct mei_cl *cl)
 {
@@ -393,12 +390,9 @@ int mei_disconnect(struct mei_device *dev, struct mei_cl *cl)
        mei_cli_disconnect->hbm_cmd = CLIENT_DISCONNECT_REQ_CMD;
        mei_cli_disconnect->reserved[0] = 0;
 
-       if (!mei_write_message(dev, mei_hdr,
+       return mei_write_message(dev, mei_hdr,
                                (unsigned char *) mei_cli_disconnect,
-                               sizeof(struct hbm_client_disconnect_request)))
-               return 0;
-
-       return 1;
+                               sizeof(struct hbm_client_disconnect_request));
 }
 
 /**
@@ -407,7 +401,7 @@ int mei_disconnect(struct mei_device *dev, struct mei_cl *cl)
  * @dev: the device structure
  * @cl: private data of the file object
  *
- * returns 1 if success, 0 - otherwise.
+ * This function returns -EIO on write failure
  */
 int mei_connect(struct mei_device *dev, struct mei_cl *cl)
 {
@@ -428,10 +422,7 @@ int mei_connect(struct mei_device *dev, struct mei_cl *cl)
        mei_cli_connect->hbm_cmd = CLIENT_CONNECT_REQ_CMD;
        mei_cli_connect->reserved = 0;
 
-       if (!mei_write_message(dev, mei_hdr,
+       return mei_write_message(dev, mei_hdr,
                                (unsigned char *) mei_cli_connect,
-                               sizeof(struct hbm_client_connect_request)))
-               return 0;
-
-       return 1;
+                               sizeof(struct hbm_client_connect_request));
 }

diff --git a/drivers/staging/mei/interrupt.c b/drivers/staging/mei/interrupt.c
index a34e2f3..2007d24 100644 (file)
--- a/drivers/staging/mei/interrupt.c
+++ b/drivers/staging/mei/interrupt.c
@@ -263,26 +263,25 @@ quit:
 static int _mei_irq_thread_iamthif_read(struct mei_device *dev, s32 *slots)
 {
 
-       if (((*slots) * sizeof(u32)) >= (sizeof(struct mei_msg_hdr)
+       if (((*slots) * sizeof(u32)) < (sizeof(struct mei_msg_hdr)
                        + sizeof(struct hbm_flow_control))) {
-               *slots -= (sizeof(struct mei_msg_hdr) +
-                               sizeof(struct hbm_flow_control) + 3) / 4;
-               if (!mei_send_flow_control(dev, &dev->iamthif_cl)) {
-                       dev_dbg(&dev->pdev->dev, "iamthif flow control failed\n");
-               } else {
-                       dev_dbg(&dev->pdev->dev, "iamthif flow control success\n");
-                       dev->iamthif_state = MEI_IAMTHIF_READING;
-                       dev->iamthif_flow_control_pending = false;
-                       dev->iamthif_msg_buf_index = 0;
-                       dev->iamthif_msg_buf_size = 0;
-                       dev->iamthif_stall_timer = IAMTHIF_STALL_TIMER;
-                       dev->mei_host_buffer_is_empty =
-                                       mei_host_buffer_is_empty(dev);
-               }
-               return 0;
-       } else {
                return -EMSGSIZE;
        }
+       *slots -= (sizeof(struct mei_msg_hdr) +
+                               sizeof(struct hbm_flow_control) + 3) / 4;
+       if (mei_send_flow_control(dev, &dev->iamthif_cl)) {
+               dev_dbg(&dev->pdev->dev, "iamthif flow control failed\n");
+               return -EIO;
+       }
+
+       dev_dbg(&dev->pdev->dev, "iamthif flow control success\n");
+       dev->iamthif_state = MEI_IAMTHIF_READING;
+       dev->iamthif_flow_control_pending = false;
+       dev->iamthif_msg_buf_index = 0;
+       dev->iamthif_msg_buf_size = 0;
+       dev->iamthif_stall_timer = IAMTHIF_STALL_TIMER;
+       dev->mei_host_buffer_is_empty = mei_host_buffer_is_empty(dev);
+       return 0;
 }
 
 /**
@@ -306,7 +305,7 @@ static int _mei_irq_thread_close(struct mei_device *dev, s32 *slots,
                *slots -= (sizeof(struct mei_msg_hdr) +
                        sizeof(struct hbm_client_disconnect_request) + 3) / 4;
 
-               if (!mei_disconnect(dev, cl)) {
+               if (mei_disconnect(dev, cl)) {
                        cl->status = 0;
                        cb_pos->information = 0;
                        list_move_tail(&cb_pos->cb_list,
@@ -838,24 +837,21 @@ static int _mei_irq_thread_read(struct mei_device *dev,   s32 *slots,
 {
        if ((*slots * sizeof(u32)) >= (sizeof(struct mei_msg_hdr) +
                        sizeof(struct hbm_flow_control))) {
-               *slots -= (sizeof(struct mei_msg_hdr) +
-                       sizeof(struct hbm_flow_control) + 3) / 4;
-               if (!mei_send_flow_control(dev, cl)) {
-                       cl->status = -ENODEV;
-                       cb_pos->information = 0;
-                       list_move_tail(&cb_pos->cb_list,
-                                       &cmpl_list->mei_cb.cb_list);
-                       return -ENODEV;
-               } else {
-                       list_move_tail(&cb_pos->cb_list,
-                                       &dev->read_list.mei_cb.cb_list);
-               }
-       } else {
                /* return the cancel routine */
                list_del(&cb_pos->cb_list);
                return -EBADMSG;
        }
 
+       *slots -= (sizeof(struct mei_msg_hdr) +
+                       sizeof(struct hbm_flow_control) + 3) / 4;
+       if (mei_send_flow_control(dev, cl)) {
+               cl->status = -ENODEV;
+               cb_pos->information = 0;
+               list_move_tail(&cb_pos->cb_list, &cmpl_list->mei_cb.cb_list);
+               return -ENODEV;
+       }
+       list_move_tail(&cb_pos->cb_list, &dev->read_list.mei_cb.cb_list);
+
        return 0;
 }
 
@@ -881,7 +877,7 @@ static int _mei_irq_thread_ioctl(struct mei_device *dev, s32 *slots,
                cl->state = MEI_FILE_CONNECTING;
                *slots -= (sizeof(struct mei_msg_hdr) +
                        sizeof(struct hbm_client_connect_request) + 3) / 4;
-               if (!mei_connect(dev, cl)) {
+               if (mei_connect(dev, cl)) {
                        cl->status = -ENODEV;
                        cb_pos->information = 0;
                        list_del(&cb_pos->cb_list);
@@ -938,7 +934,7 @@ static int _mei_irq_thread_cmpl(struct mei_device *dev,     s32 *slots,
                                mei_hdr->length);
                *slots -= (sizeof(struct mei_msg_hdr) +
                                mei_hdr->length + 3) / 4;
-               if (!mei_write_message(dev, mei_hdr,
+               if (mei_write_message(dev, mei_hdr,
                                (unsigned char *)
                                (cb_pos->request_buffer.data +
                                cb_pos->information),
@@ -967,7 +963,7 @@ static int _mei_irq_thread_cmpl(struct mei_device *dev,     s32 *slots,
 
                (*slots) -= (sizeof(struct mei_msg_hdr) +
                                mei_hdr->length + 3) / 4;
-               if (!mei_write_message(dev, mei_hdr,
+               if (mei_write_message(dev, mei_hdr,
                                        (unsigned char *)
                                        (cb_pos->request_buffer.data +
                                        cb_pos->information),
@@ -1028,7 +1024,7 @@ static int _mei_irq_thread_cmpl_iamthif(struct mei_device *dev, s32 *slots,
                *slots -= (sizeof(struct mei_msg_hdr) +
                                mei_hdr->length + 3) / 4;
 
-               if (!mei_write_message(dev, mei_hdr,
+               if (mei_write_message(dev, mei_hdr,
                                        (dev->iamthif_msg_buf +
                                        dev->iamthif_msg_buf_index),
                                        mei_hdr->length)) {
@@ -1063,7 +1059,7 @@ static int _mei_irq_thread_cmpl_iamthif(struct mei_device *dev, s32 *slots,
                *slots -= (sizeof(struct mei_msg_hdr) +
                                mei_hdr->length + 3) / 4;
 
-               if (!mei_write_message(dev, mei_hdr,
+               if (mei_write_message(dev, mei_hdr,
                                        (dev->iamthif_msg_buf +
                                        dev->iamthif_msg_buf_index),
                                        mei_hdr->length)) {

diff --git a/drivers/staging/mei/iorw.c b/drivers/staging/mei/iorw.c
index a6b9694..121b377 100644 (file)
--- a/drivers/staging/mei/iorw.c
+++ b/drivers/staging/mei/iorw.c
@@ -162,7 +162,7 @@ int mei_ioctl_connect_client(struct file *file,
            && !mei_other_client_is_connecting(dev, cl)) {
                dev_dbg(&dev->pdev->dev, "Sending Connect Message\n");
                dev->mei_host_buffer_is_empty = false;
-               if (!mei_connect(dev, cl)) {
+               if (mei_connect(dev, cl)) {
                        dev_dbg(&dev->pdev->dev, "Sending connect message - failed\n");
                        rets = -ENODEV;
                        goto end;
@@ -434,13 +434,11 @@ int mei_start_read(struct mei_device *dev, struct mei_cl *cl)
        cl->read_cb = cb;
        if (dev->mei_host_buffer_is_empty) {
                dev->mei_host_buffer_is_empty = false;
-               if (!mei_send_flow_control(dev, cl)) {
+               if (mei_send_flow_control(dev, cl)) {
                        rets = -ENODEV;
                        goto unlock;
-               } else {
-                       list_add_tail(&cb->cb_list,
-                                     &dev->read_list.mei_cb.cb_list);
                }
+               list_add_tail(&cb->cb_list, &dev->read_list.mei_cb.cb_list);
        } else {
                list_add_tail(&cb->cb_list, &dev->ctrl_wr_list.mei_cb.cb_list);
        }
@@ -500,7 +498,7 @@ int amthi_write(struct mei_device *dev, struct mei_cl_cb *cb)
                mei_hdr.me_addr = dev->iamthif_cl.me_client_id;
                mei_hdr.reserved = 0;
                dev->iamthif_msg_buf_index += mei_hdr.length;
-               if (!mei_write_message(dev, &mei_hdr,
+               if (mei_write_message(dev, &mei_hdr,
                                        (unsigned char *)(dev->iamthif_msg_buf),
                                        mei_hdr.length))
                        return -ENODEV;

diff --git a/drivers/staging/mei/main.c b/drivers/staging/mei/main.c
index 64456ce..55b3908 100644 (file)
--- a/drivers/staging/mei/main.c
+++ b/drivers/staging/mei/main.c
@@ -740,7 +740,7 @@ static ssize_t mei_write(struct file *file, const char __user *ubuf,
                mei_hdr.reserved = 0;
                dev_dbg(&dev->pdev->dev, "call mei_write_message header=%08x.\n",
                    *((u32 *) &mei_hdr));
-               if (!mei_write_message(dev, &mei_hdr,
+               if (mei_write_message(dev, &mei_hdr,
                        (unsigned char *) (write_cb->request_buffer.data),
                        mei_hdr.length)) {
                        rets = -ENODEV;

diff --git a/drivers/staging/mei/wd.c b/drivers/staging/mei/wd.c
index f397835..a6910da 100644 (file)
--- a/drivers/staging/mei/wd.c
+++ b/drivers/staging/mei/wd.c
@@ -74,7 +74,7 @@ bool mei_wd_host_init(struct mei_device *dev)
 
        dev_dbg(&dev->pdev->dev, "check wd_cl\n");
        if (MEI_FILE_CONNECTING == dev->wd_cl.state) {
-               if (!mei_connect(dev, &dev->wd_cl)) {
+               if (mei_connect(dev, &dev->wd_cl)) {
                        dev_dbg(&dev->pdev->dev, "Failed to connect to WD client\n");
                        dev->wd_cl.state = MEI_FILE_DISCONNECTED;
                        dev->wd_cl.host_client_id = 0;
@@ -119,9 +119,7 @@ int mei_wd_send(struct mei_device *dev)
        else
                return -EINVAL;
 
-       if (mei_write_message(dev, mei_hdr, dev->wd_data, mei_hdr->length))
-               return 0;
-       return -EIO;
+       return mei_write_message(dev, mei_hdr, dev->wd_data, mei_hdr->length);
 }
 
 /**