[PATCH V7 06/11] USB: f81232: implement MCR/MSR function

Peter Hung
2015-02-24T10:18:50Z

This patch implement relative MCR/MSR function, such like
tiocmget()/tiocmset()/dtr_rts()/carrier_raised()

original f81232_carrier_raised() compared with wrong value UART_DCD.
It's should compared with UART_MSR_DCD.

Signed-off-by: Peter Hung <hpeter+linux_kernel@gmail.com>
---
drivers/usb/serial/f81232.c | 103 ++++++++++++++++++++++++++++++++++----------
1 file changed, 81 insertions(+), 22 deletions(-)

diff --git a/drivers/usb/serial/f81232.c b/drivers/usb/serial/f81232.c
index 339be30..21f606f 100644
--- a/drivers/usb/serial/f81232.c
+++ b/drivers/usb/serial/f81232.c
@@ -37,6 +37,7 @@ MODULE_DEVICE_TABLE(usb, id_table);
#define F81232_SET_REGISTER 0x40

#define SERIAL_BASE_ADDRESS 0x0120
+#define MODEM_CONTROL_REGISTER (0x04 + SERIAL_BASE_ADDRESS)
#define MODEM_STATUS_REGISTER (0x06 + SERIAL_BASE_ADDRESS)

#define CONTROL_DTR 0x01
@@ -55,7 +56,7 @@ MODULE_DEVICE_TABLE(usb, id_table);

struct f81232_private {
struct mutex lock;
- u8 line_control;
+ u8 modem_control;
u8 modem_status;
struct work_struct interrupt_work;
struct usb_serial_port *port;
@@ -198,6 +199,52 @@ static void f81232_read_msr(struct usb_serial_port *port)
wake_up_interruptible(&port->port.delta_msr_wait);
}

+static int f81232_set_mctrl(struct usb_serial_port *port,
+ unsigned int set, unsigned int clear)
+{
+ u8 urb_value;
+ int status;
+ struct f81232_private *priv = usb_get_serial_port_data(port);
+
+ if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0)
+ return 0; /* no change */
+
+ /* 'set' takes precedence over 'clear' */
+ clear &= ~set;
+
+ /* force enable interrupt with OUT2 */
+ mutex_lock(&priv->lock);
+ urb_value = UART_MCR_OUT2 | priv->modem_control;
+ mutex_unlock(&priv->lock);
+
+ if (clear & TIOCM_DTR)
+ urb_value &= ~UART_MCR_DTR;
+
+ if (clear & TIOCM_RTS)
+ urb_value &= ~UART_MCR_RTS;
+
+ if (set & TIOCM_DTR)
+ urb_value |= UART_MCR_DTR;
+
+ if (set & TIOCM_RTS)
+ urb_value |= UART_MCR_RTS;
+
+ dev_dbg(&port->dev, "%s new:%02x old:%02x\n", __func__,
+ urb_value, priv->modem_control);
+
+ status = f81232_set_register(port, MODEM_CONTROL_REGISTER, urb_value);
+ if (status) {
+ dev_err(&port->dev, "%s set MCR status < 0\n", __func__);
+ return status;
+ } else {
+ mutex_lock(&priv->lock);
+ priv->modem_control = urb_value;
+ mutex_unlock(&priv->lock);
+ }
+
+ return 0;
+}
+
static void f81232_update_line_status(struct usb_serial_port *port,
unsigned char *data,
size_t actual_length)
@@ -309,12 +356,6 @@ static void f81232_process_read_urb(struct urb *urb)
tty_flip_buffer_push(&port->port);
}

-static int set_control_lines(struct usb_device *dev, u8 value)
-{
- /* FIXME - Stubbed out for now */
- return 0;
-}
-
static void f81232_break_ctl(struct tty_struct *tty, int break_state)
{
/* FIXME - Stubbed out for now */
@@ -342,15 +383,35 @@ static void f81232_set_termios(struct tty_struct *tty,

static int f81232_tiocmget(struct tty_struct *tty)
{
- /* FIXME - Stubbed out for now */
- return 0;
+ int r;
+ struct usb_serial_port *port = tty->driver_data;
+ struct f81232_private *port_priv = usb_get_serial_port_data(port);
+ u8 mcr, msr;
+
+ /* force get current MSR changed state */
+ f81232_read_msr(port);
+
+ mutex_lock(&port_priv->lock);
+ mcr = port_priv->modem_control;
+ msr = port_priv->modem_status;
+ mutex_unlock(&port_priv->lock);
+
+ r = (mcr & UART_MCR_DTR ? TIOCM_DTR : 0) |
+ (mcr & UART_MCR_RTS ? TIOCM_RTS : 0) |
+ (msr & UART_MSR_CTS ? TIOCM_CTS : 0) |
+ (msr & UART_MSR_DCD ? TIOCM_CAR : 0) |
+ (msr & UART_MSR_RI ? TIOCM_RI : 0) |
+ (msr & UART_MSR_DSR ? TIOCM_DSR : 0);
+
+ return r;
}

static int f81232_tiocmset(struct tty_struct *tty,
unsigned int set, unsigned int clear)
{
- /* FIXME - Stubbed out for now */
- return 0;
+ struct usb_serial_port *port = tty->driver_data;
+
+ return f81232_set_mctrl(port, set, clear);
}

static int f81232_open(struct tty_struct *tty, struct usb_serial_port *port)
@@ -385,24 +446,22 @@ static void f81232_close(struct usb_serial_port *port)

static void f81232_dtr_rts(struct usb_serial_port *port, int on)
{
- struct f81232_private *priv = usb_get_serial_port_data(port);
- u8 control;
-
- mutex_lock(&priv->lock);
- /* Change DTR and RTS */
if (on)
- priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
+ f81232_set_mctrl(port, TIOCM_DTR | TIOCM_RTS, 0);
else
- priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
- control = priv->line_control;
- mutex_unlock(&priv->lock);
- set_control_lines(port->serial->dev, control);
+ f81232_set_mctrl(port, 0, TIOCM_DTR | TIOCM_RTS);
}

static int f81232_carrier_raised(struct usb_serial_port *port)
{
+ u8 msr;
struct f81232_private *priv = usb_get_serial_port_data(port);
- if (priv->modem_status & UART_DCD)
+
+ mutex_lock(&priv->lock);
+ msr = priv->modem_status;
+ mutex_unlock(&priv->lock);
+
+ if (msr & UART_MSR_DCD)
return 1;
return 0;
}
--
1.9.1