From 51808f051ede81865b7af351d6c230a1ac244a22 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Fri, 26 Aug 2011 11:25:35 +0100 Subject: [PATCH] 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 Signed-off-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/mrst_max3110.c | 99 ++++++++++++++----------------- drivers/tty/serial/mrst_max3110.h | 1 + 2 files changed, 44 insertions(+), 56 deletions(-) diff --git a/drivers/tty/serial/mrst_max3110.c b/drivers/tty/serial/mrst_max3110.c index c8f986876229..42aa43934b20 100644 --- a/drivers/tty/serial/mrst_max3110.c +++ b/drivers/tty/serial/mrst_max3110.c @@ -27,6 +27,10 @@ * interrupt for a low speed UART device */ +#ifdef CONFIG_MAGIC_SYSRQ +#define SUPPORT_SYSRQ +#endif + #include #include #include @@ -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) diff --git a/drivers/tty/serial/mrst_max3110.h b/drivers/tty/serial/mrst_max3110.h index c37ea48c825a..35af0739513b 100644 --- a/drivers/tty/serial/mrst_max3110.h +++ b/drivers/tty/serial/mrst_max3110.h @@ -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)