From: Kylene Hall Replace an erroneous return code for the read function when no data is available. Signed-of-by: Kylene Hall Signed-off-by: Andrew Morton --- drivers/char/tpm/tpm.c | 30 ++++++++++-------------------- 1 files changed, 10 insertions(+), 20 deletions(-) diff -puN drivers/char/tpm/tpm.c~fix-tpm-driver-read-return-code-issue drivers/char/tpm/tpm.c --- 25/drivers/char/tpm/tpm.c~fix-tpm-driver-read-return-code-issue 2005-05-09 18:21:20.000000000 -0700 +++ 25-akpm/drivers/char/tpm/tpm.c 2005-05-09 18:21:20.000000000 -0700 @@ -489,29 +489,19 @@ ssize_t tpm_read(struct file * file, cha size_t size, loff_t * off) { struct tpm_chip *chip = file->private_data; - int ret_size = -ENODATA; + int ret_size; - if (atomic_read(&chip->data_pending) != 0) { /* Result available */ - down(&chip->timer_manipulation_mutex); - del_singleshot_timer_sync(&chip->user_read_timer); - up(&chip->timer_manipulation_mutex); + del_singleshot_timer_sync(&chip->user_read_timer); + ret_size = atomic_read(&chip->data_pending); + atomic_set(&chip->data_pending, 0); + if (ret_size > 0) { /* relay data */ + if (size < ret_size) + ret_size = size; down(&chip->buffer_mutex); - - ret_size = atomic_read(&chip->data_pending); - atomic_set(&chip->data_pending, 0); - - if (ret_size == 0) /* timeout just occurred */ - ret_size = -ETIME; - else if (ret_size > 0) { /* relay data */ - if (size < ret_size) - ret_size = size; - - if (copy_to_user((void __user *) buf, - chip->data_buffer, ret_size)) { - ret_size = -EFAULT; - } - } + if (copy_to_user + ((void __user *) buf, chip->data_buffer, ret_size)) + ret_size = -EFAULT; up(&chip->buffer_mutex); } _