diff options
| author | Felipe Balbi <balbi@ti.com> | 2011-03-21 11:25:08 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-04-23 02:31:53 +0200 |
| commit | b1c43f82c5aa265442f82dba31ce985ebb7aa71c (patch) | |
| tree | 8b344d8d5355b30e8deff901180edc708a653227 /drivers/tty/n_hdlc.c | |
| parent | Serial: Remove unused code. (diff) | |
| download | linux-b1c43f82c5aa265442f82dba31ce985ebb7aa71c.tar.xz linux-b1c43f82c5aa265442f82dba31ce985ebb7aa71c.zip | |
tty: make receive_buf() return the amout of bytes received
it makes it simpler to keep track of the amount of
bytes received and simplifies how flush_to_ldisc counts
the remaining bytes. It also fixes a bug of lost bytes
on n_tty when flushing too many bytes via the USB
serial gadget driver.
Tested-by: Stefan Bigler <stefan.bigler@keymile.com>
Tested-by: Toby Gray <toby.gray@realvnc.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/tty/n_hdlc.c')
| -rw-r--r-- | drivers/tty/n_hdlc.c | 18 |
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c index cea56033b34c..cac666314aef 100644 --- a/drivers/tty/n_hdlc.c +++ b/drivers/tty/n_hdlc.c @@ -188,8 +188,8 @@ static unsigned int n_hdlc_tty_poll(struct tty_struct *tty, struct file *filp, poll_table *wait); static int n_hdlc_tty_open(struct tty_struct *tty); static void n_hdlc_tty_close(struct tty_struct *tty); -static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *cp, - char *fp, int count); +static unsigned int n_hdlc_tty_receive(struct tty_struct *tty, + const __u8 *cp, char *fp, int count); static void n_hdlc_tty_wakeup(struct tty_struct *tty); #define bset(p,b) ((p)[(b) >> 5] |= (1 << ((b) & 0x1f))) @@ -509,8 +509,8 @@ static void n_hdlc_tty_wakeup(struct tty_struct *tty) * Called by tty low level driver when receive data is available. Data is * interpreted as one HDLC frame. */ -static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, - char *flags, int count) +static unsigned int n_hdlc_tty_receive(struct tty_struct *tty, + const __u8 *data, char *flags, int count) { register struct n_hdlc *n_hdlc = tty2n_hdlc (tty); register struct n_hdlc_buf *buf; @@ -521,20 +521,20 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, /* This can happen if stuff comes in on the backup tty */ if (!n_hdlc || tty != n_hdlc->tty) - return; + return -ENODEV; /* verify line is using HDLC discipline */ if (n_hdlc->magic != HDLC_MAGIC) { printk("%s(%d) line not using HDLC discipline\n", __FILE__,__LINE__); - return; + return -EINVAL; } if ( count>maxframe ) { if (debuglevel >= DEBUG_LEVEL_INFO) printk("%s(%d) rx count>maxframesize, data discarded\n", __FILE__,__LINE__); - return; + return -EINVAL; } /* get a free HDLC buffer */ @@ -550,7 +550,7 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, if (debuglevel >= DEBUG_LEVEL_INFO) printk("%s(%d) no more rx buffers, data discarded\n", __FILE__,__LINE__); - return; + return -EINVAL; } /* copy received data to HDLC buffer */ @@ -565,6 +565,8 @@ static void n_hdlc_tty_receive(struct tty_struct *tty, const __u8 *data, if (n_hdlc->tty->fasync != NULL) kill_fasync (&n_hdlc->tty->fasync, SIGIO, POLL_IN); + return count; + } /* end of n_hdlc_tty_receive() */ /** |