2019-11-25 13:21:35

by Shubhrajyoti Datta

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Subject: [PATCHv2 1/3] serial: xilinx_uartps: Let get_mctrl return status

From: Maarten Brock <[email protected]>

Some of the applications like microcom do not work if
modem is disabled. To fix them we always return
TIOCM_CTS | TIOCM_DSR | TIOCM_CAR instead of 0 when
using cts_override. Make get_mctrl return actual status
when not using cts_override.

Signed-off-by: Maarten Brock <[email protected]>
Signed-off-by: Shubhrajyoti Datta <[email protected]>
---
drivers/tty/serial/xilinx_uartps.c | 28 +++++++++++++++++++++++++---
1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 4e55bc3..acdb4fa5 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -158,6 +158,16 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
#define CDNS_UART_MODEMCR_DTR 0x00000001 /* Data Terminal Ready */

/*
+ * Modem Status register:
+ * The read/write Modem Status register reports the interface with the modem
+ * or data set, or a peripheral device emulating a modem.
+ */
+#define CDNS_UART_MODEMSR_DCD BIT(7) /* Data Carrier Detect */
+#define CDNS_UART_MODEMSR_RI BIT(6) /* Ting Indicator */
+#define CDNS_UART_MODEMSR_DSR BIT(5) /* Data Set Ready */
+#define CDNS_UART_MODEMSR_CTS BIT(4) /* Clear To Send */
+
+/*
* Channel Status Register:
* The channel status register (CSR) is provided to enable the control logic
* to monitor the status of bits in the channel interrupt status register,
@@ -1007,12 +1017,24 @@ static void cdns_uart_config_port(struct uart_port *port, int flags)
*/
static unsigned int cdns_uart_get_mctrl(struct uart_port *port)
{
+ u32 val;
+ unsigned int mctrl = 0;
struct cdns_uart *cdns_uart_data = port->private_data;

if (cdns_uart_data->cts_override)
- return 0;
-
- return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
+ return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
+
+ val = readl(port->membase + CDNS_UART_MODEMSR);
+ if (val & CDNS_UART_MODEMSR_CTS)
+ mctrl |= TIOCM_CTS;
+ if (val & CDNS_UART_MODEMSR_DSR)
+ mctrl |= TIOCM_DSR;
+ if (val & CDNS_UART_MODEMSR_RI)
+ mctrl |= TIOCM_RNG;
+ if (val & CDNS_UART_MODEMSR_DCD)
+ mctrl |= TIOCM_CAR;
+
+ return mctrl;
}

static void cdns_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
--
2.1.1


2019-11-25 13:22:15

by Shubhrajyoti Datta

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Subject: [PATCHv2 2/3] serial: xilinx_uartps: set_termios sets flowcontrol

From: Maarten Brock <[email protected]>

Let set_termios enable/disable automatic flow control.
set_mctrl should not touch automatic flow control.

Signed-off-by: Maarten Brock <[email protected]>
Signed-off-by: Shubhrajyoti Datta <[email protected]>
---
drivers/tty/serial/xilinx_uartps.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index acdb4fa5..e82f8db 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -694,7 +694,7 @@ static void cdns_uart_break_ctl(struct uart_port *port, int ctl)
static void cdns_uart_set_termios(struct uart_port *port,
struct ktermios *termios, struct ktermios *old)
{
- unsigned int cval = 0;
+ u32 cval = 0;
unsigned int baud, minbaud, maxbaud;
unsigned long flags;
unsigned int ctrl_reg, mode_reg, val;
@@ -815,6 +815,13 @@ static void cdns_uart_set_termios(struct uart_port *port,
cval |= mode_reg & 1;
writel(cval, port->membase + CDNS_UART_MR);

+ cval = readl(port->membase + CDNS_UART_MODEMCR);
+ if (termios->c_cflag & CRTSCTS)
+ cval |= CDNS_UART_MODEMCR_FCM;
+ else
+ cval &= ~CDNS_UART_MODEMCR_FCM;
+ writel(cval, port->membase + CDNS_UART_MODEMCR);
+
spin_unlock_irqrestore(&port->lock, flags);
}

@@ -1049,12 +1056,9 @@ static void cdns_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
val = readl(port->membase + CDNS_UART_MODEMCR);
mode_reg = readl(port->membase + CDNS_UART_MR);

- val &= ~(CDNS_UART_MODEMCR_RTS | CDNS_UART_MODEMCR_DTR |
- CDNS_UART_MODEMCR_FCM);
+ val &= ~(CDNS_UART_MODEMCR_RTS | CDNS_UART_MODEMCR_DTR);
mode_reg &= ~CDNS_UART_MR_CHMODE_MASK;

- if (mctrl & TIOCM_RTS || mctrl & TIOCM_DTR)
- val |= CDNS_UART_MODEMCR_FCM;
if (mctrl & TIOCM_LOOP)
mode_reg |= CDNS_UART_MR_CHMODE_L_LOOP;
else
--
2.1.1

2019-11-25 13:22:30

by Shubhrajyoti Datta

[permalink] [raw]
Subject: [PATCHv2 3/3] serial: xilinx_uartps: set_mctrl sets RTS and DTR

From: Maarten Brock <[email protected]>

set_mctrl now sets RTS and DTR.

Signed-off-by: Maarten Brock <[email protected]>
Signed-off-by: Shubhrajyoti Datta <[email protected]>
---
drivers/tty/serial/xilinx_uartps.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index e82f8db..b4fd550 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -1059,6 +1059,10 @@ static void cdns_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
val &= ~(CDNS_UART_MODEMCR_RTS | CDNS_UART_MODEMCR_DTR);
mode_reg &= ~CDNS_UART_MR_CHMODE_MASK;

+ if (mctrl & TIOCM_RTS)
+ val |= CDNS_UART_MODEMCR_RTS;
+ if (mctrl & TIOCM_DTR)
+ val |= CDNS_UART_MODEMCR_DTR;
if (mctrl & TIOCM_LOOP)
mode_reg |= CDNS_UART_MR_CHMODE_L_LOOP;
else
--
2.1.1