Check to see if allocation by kzalloc() or usb_alloc_urb() was unsuccessful immediately after the allocation. Exit from the function can be right at that point in case of allocation failure. This avoids unnecessary use of usb_alloc_urb() & usb_free_urb() if kzalloc() returns NULL. Also, makes the code better structured & easier to understand.
Signed-off-by: Harsh Kumar <[email protected]> --- drivers/staging/winbond/wb35reg.c | 265 +++++++++++++++++++++++++++++++------------------------------- 1 file changed, 136 insertions(+), 129 deletions(-) diff -uprN a/drivers/staging/winbond/wb35reg.c b/drivers/staging/winbond/wb35reg.c --- a/drivers/staging/winbond/wb35reg.c 2013-05-31 19:47:16.824056618 +0530 +++ b/drivers/staging/winbond/wb35reg.c 2013-05-31 20:03:17.560035177 +0530 @@ -30,45 +30,46 @@ unsigned char Wb35Reg_BurstWrite(struct /* Trying to use burst write function if use new hardware */ UrbSize = sizeof(struct wb35_reg_queue) + DataSize + sizeof(struct usb_ctrlrequest); reg_queue = kzalloc(UrbSize, GFP_ATOMIC); + if (reg_queue == NULL) + return false; + urb = usb_alloc_urb(0, GFP_ATOMIC); - if (urb && reg_queue) { - reg_queue->DIRECT = 2; /* burst write register */ - reg_queue->INDEX = RegisterNo; - reg_queue->pBuffer = (u32 *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue)); - memcpy(reg_queue->pBuffer, pRegisterData, DataSize); - /* the function for reversing register data from little endian to big endian */ - for (i = 0; i < NumberOfData ; i++) - reg_queue->pBuffer[i] = cpu_to_le32(reg_queue->pBuffer[i]); - - dr = (struct usb_ctrlrequest *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue) + DataSize); - dr->bRequestType = USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE; - dr->bRequest = 0x04; /* USB or vendor-defined request code, burst mode */ - dr->wValue = cpu_to_le16(Flag); /* 0: Register number auto-increment, 1: No auto increment */ - dr->wIndex = cpu_to_le16(RegisterNo); - dr->wLength = cpu_to_le16(DataSize); - reg_queue->Next = NULL; - reg_queue->pUsbReq = dr; - reg_queue->urb = urb; - - spin_lock_irq(®->EP0VM_spin_lock); - if (reg->reg_first == NULL) - reg->reg_first = reg_queue; - else - reg->reg_last->Next = reg_queue; - reg->reg_last = reg_queue; - - spin_unlock_irq(®->EP0VM_spin_lock); - - /* Start EP0VM */ - Wb35Reg_EP0VM_start(pHwData); - - return true; - } else { - usb_free_urb(urb); + if (urb == NULL) { kfree(reg_queue); return false; } - return false; + + reg_queue->DIRECT = 2; /* burst write register */ + reg_queue->INDEX = RegisterNo; + reg_queue->pBuffer = (u32 *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue)); + memcpy(reg_queue->pBuffer, pRegisterData, DataSize); + /* the function for reversing register data from little endian to big endian */ + for (i = 0; i < NumberOfData ; i++) + reg_queue->pBuffer[i] = cpu_to_le32(reg_queue->pBuffer[i]); + + dr = (struct usb_ctrlrequest *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue) + DataSize); + dr->bRequestType = USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE; + dr->bRequest = 0x04; /* USB or vendor-defined request code, burst mode */ + dr->wValue = cpu_to_le16(Flag); /* 0: Register number auto-increment, 1: No auto increment */ + dr->wIndex = cpu_to_le16(RegisterNo); + dr->wLength = cpu_to_le16(DataSize); + reg_queue->Next = NULL; + reg_queue->pUsbReq = dr; + reg_queue->urb = urb; + + spin_lock_irq(®->EP0VM_spin_lock); + if (reg->reg_first == NULL) + reg->reg_first = reg_queue; + else + reg->reg_last->Next = reg_queue; + reg->reg_last = reg_queue; + + spin_unlock_irq(®->EP0VM_spin_lock); + + /* Start EP0VM */ + Wb35Reg_EP0VM_start(pHwData); + + return true; } void Wb35Reg_Update(struct hw_data *pHwData, u16 RegisterNo, u32 RegisterValue) @@ -173,42 +174,44 @@ unsigned char Wb35Reg_Write(struct hw_da /* update the register by send urb request */ UrbSize = sizeof(struct wb35_reg_queue) + sizeof(struct usb_ctrlrequest); reg_queue = kzalloc(UrbSize, GFP_ATOMIC); + if (reg_queue == NULL) + return false; + urb = usb_alloc_urb(0, GFP_ATOMIC); - if (urb && reg_queue) { - reg_queue->DIRECT = 1; /* burst write register */ - reg_queue->INDEX = RegisterNo; - reg_queue->VALUE = cpu_to_le32(RegisterValue); - reg_queue->RESERVED_VALID = false; - dr = (struct usb_ctrlrequest *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue)); - dr->bRequestType = USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE; - dr->bRequest = 0x03; /* USB or vendor-defined request code, burst mode */ - dr->wValue = cpu_to_le16(0x0); - dr->wIndex = cpu_to_le16(RegisterNo); - dr->wLength = cpu_to_le16(4); - - /* Enter the sending queue */ - reg_queue->Next = NULL; - reg_queue->pUsbReq = dr; - reg_queue->urb = urb; - - spin_lock_irq(®->EP0VM_spin_lock); - if (reg->reg_first == NULL) - reg->reg_first = reg_queue; - else - reg->reg_last->Next = reg_queue; - reg->reg_last = reg_queue; - - spin_unlock_irq(®->EP0VM_spin_lock); - - /* Start EP0VM */ - Wb35Reg_EP0VM_start(pHwData); - - return true; - } else { - usb_free_urb(urb); + if (urb == NULL) { kfree(reg_queue); return false; } + + reg_queue->DIRECT = 1; /* burst write register */ + reg_queue->INDEX = RegisterNo; + reg_queue->VALUE = cpu_to_le32(RegisterValue); + reg_queue->RESERVED_VALID = false; + dr = (struct usb_ctrlrequest *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue)); + dr->bRequestType = USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE; + dr->bRequest = 0x03; /* USB or vendor-defined request code, burst mode */ + dr->wValue = cpu_to_le16(0x0); + dr->wIndex = cpu_to_le16(RegisterNo); + dr->wLength = cpu_to_le16(4); + + /* Enter the sending queue */ + reg_queue->Next = NULL; + reg_queue->pUsbReq = dr; + reg_queue->urb = urb; + + spin_lock_irq(®->EP0VM_spin_lock); + if (reg->reg_first == NULL) + reg->reg_first = reg_queue; + else + reg->reg_last->Next = reg_queue; + reg->reg_last = reg_queue; + + spin_unlock_irq(®->EP0VM_spin_lock); + + /* Start EP0VM */ + Wb35Reg_EP0VM_start(pHwData); + + return true; } /* @@ -236,42 +239,45 @@ unsigned char Wb35Reg_WriteWithCallbackV /* update the register by send urb request */ UrbSize = sizeof(struct wb35_reg_queue) + sizeof(struct usb_ctrlrequest); reg_queue = kzalloc(UrbSize, GFP_ATOMIC); + if (reg_queue == NULL) + return false; + urb = usb_alloc_urb(0, GFP_ATOMIC); - if (urb && reg_queue) { - reg_queue->DIRECT = 1; /* burst write register */ - reg_queue->INDEX = RegisterNo; - reg_queue->VALUE = cpu_to_le32(RegisterValue); - /* NOTE : Users must guarantee the size of value will not exceed the buffer size. */ - memcpy(reg_queue->RESERVED, pValue, Len); - reg_queue->RESERVED_VALID = true; - dr = (struct usb_ctrlrequest *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue)); - dr->bRequestType = USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE; - dr->bRequest = 0x03; /* USB or vendor-defined request code, burst mode */ - dr->wValue = cpu_to_le16(0x0); - dr->wIndex = cpu_to_le16(RegisterNo); - dr->wLength = cpu_to_le16(4); - - /* Enter the sending queue */ - reg_queue->Next = NULL; - reg_queue->pUsbReq = dr; - reg_queue->urb = urb; - spin_lock_irq(®->EP0VM_spin_lock); - if (reg->reg_first == NULL) - reg->reg_first = reg_queue; - else - reg->reg_last->Next = reg_queue; - reg->reg_last = reg_queue; - - spin_unlock_irq(®->EP0VM_spin_lock); - - /* Start EP0VM */ - Wb35Reg_EP0VM_start(pHwData); - return true; - } else { - usb_free_urb(urb); + if (urb == NULL) { kfree(reg_queue); return false; } + + reg_queue->DIRECT = 1; /* burst write register */ + reg_queue->INDEX = RegisterNo; + reg_queue->VALUE = cpu_to_le32(RegisterValue); + /* NOTE : Users must guarantee the size of value will not exceed the buffer size. */ + memcpy(reg_queue->RESERVED, pValue, Len); + reg_queue->RESERVED_VALID = true; + dr = (struct usb_ctrlrequest *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue)); + dr->bRequestType = USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_DEVICE; + dr->bRequest = 0x03; /* USB or vendor-defined request code, burst mode */ + dr->wValue = cpu_to_le16(0x0); + dr->wIndex = cpu_to_le16(RegisterNo); + dr->wLength = cpu_to_le16(4); + + /* Enter the sending queue */ + reg_queue->Next = NULL; + reg_queue->pUsbReq = dr; + reg_queue->urb = urb; + spin_lock_irq(®->EP0VM_spin_lock); + if (reg->reg_first == NULL) + reg->reg_first = reg_queue; + else + reg->reg_last->Next = reg_queue; + reg->reg_last = reg_queue; + + spin_unlock_irq(®->EP0VM_spin_lock); + + /* Start EP0VM */ + Wb35Reg_EP0VM_start(pHwData); + + return true; } /* @@ -341,40 +347,41 @@ unsigned char Wb35Reg_Read(struct hw_dat /* update the variable by send Urb to read register */ UrbSize = sizeof(struct wb35_reg_queue) + sizeof(struct usb_ctrlrequest); reg_queue = kzalloc(UrbSize, GFP_ATOMIC); + if (reg_queue == NULL) + return false; + urb = usb_alloc_urb(0, GFP_ATOMIC); - if (urb && reg_queue) { - reg_queue->DIRECT = 0; /* read register */ - reg_queue->INDEX = RegisterNo; - reg_queue->pBuffer = pRegisterValue; - dr = (struct usb_ctrlrequest *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue)); - dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN; - dr->bRequest = 0x01; /* USB or vendor-defined request code, burst mode */ - dr->wValue = cpu_to_le16(0x0); - dr->wIndex = cpu_to_le16(RegisterNo); - dr->wLength = cpu_to_le16(4); - - /* Enter the sending queue */ - reg_queue->Next = NULL; - reg_queue->pUsbReq = dr; - reg_queue->urb = urb; - spin_lock_irq(®->EP0VM_spin_lock); - if (reg->reg_first == NULL) - reg->reg_first = reg_queue; - else - reg->reg_last->Next = reg_queue; - reg->reg_last = reg_queue; - - spin_unlock_irq(®->EP0VM_spin_lock); - - /* Start EP0VM */ - Wb35Reg_EP0VM_start(pHwData); - - return true; - } else { - usb_free_urb(urb); + if (urb == NULL) { kfree(reg_queue); return false; } + reg_queue->DIRECT = 0; /* read register */ + reg_queue->INDEX = RegisterNo; + reg_queue->pBuffer = pRegisterValue; + dr = (struct usb_ctrlrequest *)((u8 *)reg_queue + sizeof(struct wb35_reg_queue)); + dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN; + dr->bRequest = 0x01; /* USB or vendor-defined request code, burst mode */ + dr->wValue = cpu_to_le16(0x0); + dr->wIndex = cpu_to_le16(RegisterNo); + dr->wLength = cpu_to_le16(4); + + /* Enter the sending queue */ + reg_queue->Next = NULL; + reg_queue->pUsbReq = dr; + reg_queue->urb = urb; + spin_lock_irq(®->EP0VM_spin_lock); + if (reg->reg_first == NULL) + reg->reg_first = reg_queue; + else + reg->reg_last->Next = reg_queue; + reg->reg_last = reg_queue; + + spin_unlock_irq(®->EP0VM_spin_lock); + + /* Start EP0VM */ + Wb35Reg_EP0VM_start(pHwData); + + return true; } _______________________________________________ devel mailing list [email protected] http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
