max3110: add sysrq support

This patch moves several occurences of similar code inside receive_chars(),
which now also takes care of checking for break and calling sysrq handling
code.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alexander Shishkin 2011-08-26 11:25:35 +01:00 committed by Greg Kroah-Hartman
parent efe3ed9837
commit 51808f051e
2 changed files with 44 additions and 56 deletions

View File

@ -27,6 +27,10 @@
* interrupt for a low speed UART device
*/
#ifdef CONFIG_MAGIC_SYSRQ
#define SUPPORT_SYSRQ
#endif
#include <linux/module.h>
#include <linux/ioport.h>
#include <linux/irq.h>
@ -73,9 +77,9 @@ struct uart_max3110 {
/* global data structure, may need be removed */
static struct uart_max3110 *pmax;
static void receive_chars(struct uart_max3110 *max,
unsigned char *str, int len);
static int max3110_read_multi(struct uart_max3110 *max, u8 *buf);
static int receive_chars(struct uart_max3110 *max,
unsigned short *str, int len);
static int max3110_read_multi(struct uart_max3110 *max);
static void max3110_con_receive(struct uart_max3110 *max);
static int max3110_write_then_read(struct uart_max3110 *max,
@ -108,7 +112,6 @@ static int max3110_out(struct uart_max3110 *max, const u16 out)
{
void *buf;
u16 *obuf, *ibuf;
u8 ch;
int ret;
buf = kzalloc(8, GFP_KERNEL | GFP_DMA);
@ -125,11 +128,7 @@ static int max3110_out(struct uart_max3110 *max, const u16 out)
goto exit;
}
/* If some valid data is read back */
if (*ibuf & MAX3110_READ_DATA_AVAILABLE) {
ch = *ibuf & 0xff;
receive_chars(max, &ch, 1);
}
receive_chars(max, ibuf, 1);
exit:
kfree(buf);
@ -142,12 +141,11 @@ exit:
*
* Return how many valide bytes are read back
*/
static int max3110_read_multi(struct uart_max3110 *max, u8 *rxbuf)
static int max3110_read_multi(struct uart_max3110 *max)
{
void *buf;
u16 *obuf, *ibuf;
u8 *pbuf, valid_str[M3110_RX_FIFO_DEPTH];
int i, j, blen;
int ret, blen;
blen = M3110_RX_FIFO_DEPTH * sizeof(u16);
buf = kzalloc(blen * 2, GFP_KERNEL | GFP_DMA);
@ -165,19 +163,10 @@ static int max3110_read_multi(struct uart_max3110 *max, u8 *rxbuf)
return 0;
}
/* If caller doesn't provide a buffer, then handle received char */
pbuf = rxbuf ? rxbuf : valid_str;
for (i = 0, j = 0; i < M3110_RX_FIFO_DEPTH; i++) {
if (ibuf[i] & MAX3110_READ_DATA_AVAILABLE)
pbuf[j++] = ibuf[i] & 0xff;
}
if (j && (pbuf == valid_str))
receive_chars(max, valid_str, j);
ret = receive_chars(max, ibuf, M3110_RX_FIFO_DEPTH);
kfree(buf);
return j;
return ret;
}
static void serial_m3110_con_putchar(struct uart_port *port, int ch)
@ -276,8 +265,7 @@ static void send_circ_buf(struct uart_max3110 *max,
{
void *buf;
u16 *obuf, *ibuf;
u8 valid_str[WORDS_PER_XFER];
int i, j, len, blen, dma_size, left, ret = 0;
int i, len, blen, dma_size, left, ret = 0;
dma_size = WORDS_PER_XFER * sizeof(u16) * 2;
@ -307,13 +295,7 @@ static void send_circ_buf(struct uart_max3110 *max,
pr_warning(PR_FMT "%s(): get err msg %d\n",
__func__, ret);
for (i = 0, j = 0; i < len; i++) {
if (ibuf[i] & MAX3110_READ_DATA_AVAILABLE)
valid_str[j++] = ibuf[i] & 0xff;
}
if (j)
receive_chars(max, valid_str, j);
receive_chars(max, ibuf, len);
max->port.icount.tx += len;
left -= len;
@ -353,30 +335,48 @@ static void serial_m3110_start_tx(struct uart_port *port)
wake_up(&max->wq);
}
static void receive_chars(struct uart_max3110 *max, unsigned char *str, int len)
static int
receive_chars(struct uart_max3110 *max, unsigned short *str, int len)
{
struct uart_port *port = &max->port;
struct tty_struct *tty;
int usable;
char buf[M3110_RX_FIFO_DEPTH];
int r, w, usable;
/* If uart is not opened, just return */
if (!port->state)
return;
return 0;
tty = port->state->port.tty;
if (!tty)
return;
return 0;
while (len) {
usable = tty_buffer_request_room(tty, len);
for (r = 0, w = 0; r < len; r++) {
if (str[r] & MAX3110_BREAK &&
uart_handle_break(port))
continue;
if (str[r] & MAX3110_READ_DATA_AVAILABLE) {
if (uart_handle_sysrq_char(port, str[r] & 0xff))
continue;
buf[w++] = str[r] & 0xff;
}
}
if (!w)
return 0;
for (r = 0; w; r += usable, w -= usable) {
usable = tty_buffer_request_room(tty, w);
if (usable) {
tty_insert_flip_string(tty, str, usable);
str += usable;
tty_insert_flip_string(tty, buf + r, usable);
port->icount.rx += usable;
}
len -= usable;
}
tty_flip_buffer_push(tty);
return r;
}
/*
@ -391,28 +391,15 @@ static void receive_chars(struct uart_max3110 *max, unsigned char *str, int len)
*/
static void max3110_con_receive(struct uart_max3110 *max)
{
int loop = 1, num, total = 0;
u8 recv_buf[512], *pbuf;
int loop = 1, num;
pbuf = recv_buf;
do {
num = max3110_read_multi(max, pbuf);
num = max3110_read_multi(max);
if (num) {
loop = 5;
pbuf += num;
total += num;
if (total >= 504) {
receive_chars(max, recv_buf, total);
pbuf = recv_buf;
total = 0;
}
}
} while (--loop);
if (total)
receive_chars(max, recv_buf, total);
}
static int max3110_main_thread(void *_max)

View File

@ -7,6 +7,7 @@
/* status bits for all 4 MAX3110 operate modes */
#define MAX3110_READ_DATA_AVAILABLE (1 << 15)
#define MAX3110_WRITE_BUF_EMPTY (1 << 14)
#define MAX3110_BREAK (1 << 10)
#define WC_TAG (3 << 14)
#define RC_TAG (1 << 14)