From akpm@linux-foundation.org Thu May 10 23:05:06 2007 Message-Id: <200705110604.l4B64CG5008266@shell0.pdx.osdl.net> From: Simon Arlott Subject: USB: cxacru: create sysfs attributes in atm_start instead of bind To: greg@kroah.com Cc: akpm@linux-foundation.org, simon@fire.lp0.eu, duncan.sands@math.u-psud.fr, gregkh@suse.de From: akpm@linux-foundation.org Date: Thu, 10 May 2007 23:04:12 -0700 From: Simon Arlott Since usbatm doesn't set the usb_interface driver data until after calling bind and heavy_init, it would be NULL when the sysfs attributes are read. Reading the MAC address from atm_dev before atm_dev exists would have been be possible too. Calling create_device_file in atm_start will avoid this problem, and the data is useless until the first status poll runs. However, it must be ready before a status poll does a printk on line status change otherwise userspace could react before the files exist. For completeness I've moved remove_device_file to atm_stop so it's not called in unbind when it's not needed. There's no point starting ADSL if atm_start could still fail either. Signed-off-by: Simon Arlott Cc: Duncan Sands Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman --- drivers/usb/atm/cxacru.c | 45 +++++++++++++++++++++++++-------------------- 1 file changed, 25 insertions(+), 20 deletions(-) --- a/drivers/usb/atm/cxacru.c +++ b/drivers/usb/atm/cxacru.c @@ -618,10 +618,22 @@ static int cxacru_card_status(struct cxa return 0; } +static void cxacru_remove_device_files(struct usbatm_data *usbatm_instance, + struct atm_dev *atm_dev) +{ + struct usb_interface *intf = usbatm_instance->usb_intf; + + #define CXACRU_DEVICE_REMOVE_FILE(_name) \ + device_remove_file(&intf->dev, &dev_attr_##_name); + CXACRU_ALL_FILES(REMOVE); + #undef CXACRU_DEVICE_REMOVE_FILE +} + static int cxacru_atm_start(struct usbatm_data *usbatm_instance, struct atm_dev *atm_dev) { struct cxacru_data *instance = usbatm_instance->driver_data; + struct usb_interface *intf = usbatm_instance->usb_intf; /* struct atm_dev *atm_dev = usbatm_instance->atm_dev; */ @@ -638,6 +650,13 @@ static int cxacru_atm_start(struct usbat return ret; } + #define CXACRU_DEVICE_CREATE_FILE(_name) \ + ret = device_create_file(&intf->dev, &dev_attr_##_name); \ + if (unlikely(ret)) \ + goto fail_sysfs; + CXACRU_ALL_FILES(CREATE); + #undef CXACRU_DEVICE_CREATE_FILE + /* start ADSL */ mutex_lock(&instance->adsl_state_serialize); ret = cxacru_cm(instance, CM_REQUEST_CHIP_ADSL_LINE_START, NULL, 0, NULL, 0); @@ -669,6 +688,11 @@ static int cxacru_atm_start(struct usbat if (start_polling) cxacru_poll_status(&instance->poll_work.work); return 0; + +fail_sysfs: + usb_err(usbatm_instance, "cxacru_atm_start: device_create_file failed (%d)\n", ret); + cxacru_remove_device_files(usbatm_instance, atm_dev); + return ret; } static void cxacru_poll_status(struct work_struct *work) @@ -1054,13 +1078,6 @@ static int cxacru_bind(struct usbatm_dat goto fail; } - #define CXACRU_DEVICE_CREATE_FILE(_name) \ - ret = device_create_file(&intf->dev, &dev_attr_##_name); \ - if (unlikely(ret)) \ - goto fail_sysfs; - CXACRU_ALL_FILES(CREATE); - #undef CXACRU_DEVICE_CREATE_FILE - usb_fill_int_urb(instance->rcv_urb, usb_dev, usb_rcvintpipe(usb_dev, CXACRU_EP_CMD), instance->rcv_buf, PAGE_SIZE, @@ -1081,14 +1098,6 @@ static int cxacru_bind(struct usbatm_dat return 0; - fail_sysfs: - dbg("cxacru_bind: device_create_file failed (%d)\n", ret); - - #define CXACRU_DEVICE_REMOVE_FILE(_name) \ - device_remove_file(&intf->dev, &dev_attr_##_name); - CXACRU_ALL_FILES(REMOVE); - #undef CXACRU_DEVICE_REVOVE_FILE - fail: free_page((unsigned long) instance->snd_buf); free_page((unsigned long) instance->rcv_buf); @@ -1135,11 +1144,6 @@ static void cxacru_unbind(struct usbatm_ free_page((unsigned long) instance->snd_buf); free_page((unsigned long) instance->rcv_buf); - #define CXACRU_DEVICE_REMOVE_FILE(_name) \ - device_remove_file(&intf->dev, &dev_attr_##_name); - CXACRU_ALL_FILES(REMOVE); - #undef CXACRU_DEVICE_REVOVE_FILE - kfree(instance); usbatm_instance->driver_data = NULL; @@ -1220,6 +1224,7 @@ static struct usbatm_driver cxacru_drive .heavy_init = cxacru_heavy_init, .unbind = cxacru_unbind, .atm_start = cxacru_atm_start, + .atm_stop = cxacru_remove_device_files, .bulk_in = CXACRU_EP_DATA, .bulk_out = CXACRU_EP_DATA, .rx_padding = 3,