From b1c43f82c5aa265442f82dba31ce985ebb7aa71c Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Mon, 21 Mar 2011 12:25:08 +0200 Subject: 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 Tested-by: Toby Gray Signed-off-by: Felipe Balbi Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_hdlc.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) (limited to 'drivers/tty/n_hdlc.c') diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c index cea56033b34..cac666314ae 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() */ /** -- cgit v1.2.3-18-g5258