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| author | Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com> | 2011-08-24 16:14:22 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-08-24 22:29:44 (GMT) |
| commit | 9d898966c4a07e4a5092215b5a2829d0ef02baa2 (patch) | |
| tree | 0ba12a03b2b04b2c7203c5324c13146db950b75c /drivers/tty/serial/jsm/jsm.h | |
| parent | d64bbeb57f9901b6919fabd1e5a555e94748c255 (diff) | |
| download | linux-fsl-qoriq-9d898966c4a07e4a5092215b5a2829d0ef02baa2.tar.xz | |
jsm: remove buggy write queue
jsm uses a write queue that copies from uart_core circular buffer. This
copying however has some bugs, like not wrapping the head counter. Since
this write queue is also a circular buffer, the consumer function is
ready to use the uart_core circular buffer directly.
This buggy copying function was making some bytes be dropped when
transmitting to a raw tty, doing something like this.
[root@hostname ~]$ cat /dev/ttyn1 > cascardo/dump &
[1] 2658
[root@hostname ~]$ cat /proc/tty/drivers > /dev/ttyn0
[root@hostname ~]$ cat /proc/tty/drivers
/dev/tty /dev/tty 5 0 system:/dev/tty
/dev/console /dev/console 5 1 system:console
/dev/ptmx /dev/ptmx 5 2 system
/dev/vc/0 /dev/vc/0 4 0 system:vtmaster
jsm /dev/ttyn 250 0-31 serial
serial /dev/ttyS 4 64-95 serial
hvc /dev/hvc 229 0-7 system
pty_slave /dev/pts 136 0-1048575 pty:slave
pty_master /dev/ptm 128 0-1048575 pty:master
unknown /dev/tty 4 1-63 console
[root@hostname ~]$ cat cascardo/dump
/dev/tty /dev/tty 5 0 system:/dev/tty
/dev/console /dev/console 5 1 system:console
/dev/ptmx /dev/ptmx 5 2 system
/dev/vc/0 /dev/vc/0 4 0 system:vtmaste[root@hostname ~]$
This patch drops the driver write queue entirely, using the circular
buffer from uart_core only.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/tty/serial/jsm/jsm.h')
| -rw-r--r-- | drivers/tty/serial/jsm/jsm.h | 7 |
1 files changed, 0 insertions, 7 deletions
diff --git a/drivers/tty/serial/jsm/jsm.h b/drivers/tty/serial/jsm/jsm.h index cd53bdd..529bec6 100644 --- a/drivers/tty/serial/jsm/jsm.h +++ b/drivers/tty/serial/jsm/jsm.h @@ -180,10 +180,8 @@ struct jsm_board /* Our Read/Error/Write queue sizes */ #define RQUEUEMASK 0x1FFF /* 8 K - 1 */ #define EQUEUEMASK 0x1FFF /* 8 K - 1 */ -#define WQUEUEMASK 0x0FFF /* 4 K - 1 */ #define RQUEUESIZE (RQUEUEMASK + 1) #define EQUEUESIZE RQUEUESIZE -#define WQUEUESIZE (WQUEUEMASK + 1) /************************************************************************ @@ -223,10 +221,6 @@ struct jsm_channel { u16 ch_e_head; /* Head location of the error queue */ u16 ch_e_tail; /* Tail location of the error queue */ - u8 *ch_wqueue; /* Our write queue buffer - malloc'ed */ - u16 ch_w_head; /* Head location of the write queue */ - u16 ch_w_tail; /* Tail location of the write queue */ - u64 ch_rxcount; /* total of data received so far */ u64 ch_txcount; /* total of data transmitted so far */ @@ -375,7 +369,6 @@ extern int jsm_debug; * Prototypes for non-static functions used in more than one module * *************************************************************************/ -int jsm_tty_write(struct uart_port *port); int jsm_tty_init(struct jsm_board *); int jsm_uart_port_init(struct jsm_board *); int jsm_remove_uart_port(struct jsm_board *); |