This is a request for more information.
On 02/24/2016 06:41 PM, Alison Wang wrote:
In general, a carriage return needs to execute before a line feed. The patch is to change some serial drivers based on this rule, such as serial_mxc.c, serial_pxa.c, serial_s3c24x0.c and usbtty.c.
You write "In general, a carriage return needs to execute before a line feed. The patch is to change some serial drivers based on this rule"
Please provide a reference. I'd probably benefit from deeper knowledge of this subject. I had not heard this rule before.
Thank you, Jim
Signed-off-by: Alison Wang alison.wang@nxp.com
drivers/serial/serial_mxc.c | 8 ++++---- drivers/serial/serial_pxa.c | 8 ++++---- drivers/serial/serial_s3c24x0.c | 8 ++++---- drivers/serial/usbtty.c | 7 ++++--- 4 files changed, 16 insertions(+), 15 deletions(-)
diff --git a/drivers/serial/serial_mxc.c b/drivers/serial/serial_mxc.c index 51485c0..1563bb3 100644 --- a/drivers/serial/serial_mxc.c +++ b/drivers/serial/serial_mxc.c @@ -164,15 +164,15 @@ static int mxc_serial_getc(void)
static void mxc_serial_putc(const char c) {
/* If \n, also do \r */
if (c == '\n')
serial_putc('\r');__REG(UART_PHYS + UTXD) = c;
/* wait for transmitter to be ready */ while (!(__REG(UART_PHYS + UTS) & UTS_TXEMPTY)) WATCHDOG_RESET();
/* If \n, also do \r */
if (c == '\n')
serial_putc ('\r');}
/*
diff --git a/drivers/serial/serial_pxa.c b/drivers/serial/serial_pxa.c index 8fbcc10..1eb19ec 100644 --- a/drivers/serial/serial_pxa.c +++ b/drivers/serial/serial_pxa.c @@ -156,6 +156,10 @@ void pxa_putc_dev(unsigned int uart_index, const char c) { struct pxa_uart_regs *uart_regs;
- /* If \n, also do \r */
- if (c == '\n')
pxa_putc_dev(uart_index, '\r');- uart_regs = pxa_uart_index_to_regs(uart_index); if (!uart_regs) hang();
@@ -163,10 +167,6 @@ void pxa_putc_dev(unsigned int uart_index, const char c) while (!(readl(&uart_regs->lsr) & LSR_TEMT)) WATCHDOG_RESET(); writel(c, &uart_regs->thr);
/* If \n, also do \r */
if (c == '\n')
pxa_putc_dev (uart_index,'\r');}
/*
diff --git a/drivers/serial/serial_s3c24x0.c b/drivers/serial/serial_s3c24x0.c index d4e7df2..0f0878a 100644 --- a/drivers/serial/serial_s3c24x0.c +++ b/drivers/serial/serial_s3c24x0.c @@ -135,14 +135,14 @@ static void _serial_putc(const char c, const int dev_index) { struct s3c24x0_uart *uart = s3c24x0_get_base_uart(dev_index);
/* If \n, also do \r */
if (c == '\n')
serial_putc('\r');while (!(readl(&uart->utrstat) & 0x2)) /* wait for room in the tx FIFO */ ;
writeb(c, &uart->utxh);
/* If \n, also do \r */
if (c == '\n')
serial_putc('\r');}
static inline void serial_putc_dev(unsigned int dev_index, const char c)
diff --git a/drivers/serial/usbtty.c b/drivers/serial/usbtty.c index 75f0ec3..2e19813 100644 --- a/drivers/serial/usbtty.c +++ b/drivers/serial/usbtty.c @@ -434,11 +434,12 @@ void usbtty_putc(struct stdio_dev *dev, const char c) if (!usbtty_configured ()) return;
- buf_push (&usbtty_output, &c, 1); /* If \n, also do \r */ if (c == '\n') buf_push (&usbtty_output, "\r", 1);
- buf_push(&usbtty_output, &c, 1);
- /* Poll at end to handle new data... */ if ((usbtty_output.size + 2) >= usbtty_output.totalsize) { usbtty_poll ();
@@ -498,8 +499,8 @@ void usbtty_puts(struct stdio_dev *dev, const char *str) n = next_nl_pos (str);
if (str[n] == '\n') {
__usbtty_puts (str, n + 1);__usbtty_puts ("\r", 1);
__usbtty_puts("\r", 1);__usbtty_puts(str, n + 1); str += (n + 1); len -= (n + 1);