usb: gadget: u_serial: add .get_icount() support

Add icount support for the transmitting and receiving characters. This
will make the tty LED trigger work with the ttyGS devices.

Signed-off-by: Michael Walle <mwalle@kernel.org>
Link: https://lore.kernel.org/r/20240730193840.2580358-1-mwalle@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c
index eec7f7a2e40f08bb2e002c9014a21136439d756c..bbc5f7617a136470e86b6a1659df0386623ae7d7 100644 (file)
--- a/drivers/usb/gadget/function/u_serial.c
+++ b/drivers/usb/gadget/function/u_serial.c
@@ -28,6 +28,7 @@
 #include <linux/kthread.h>
 #include <linux/workqueue.h>
 #include <linux/kfifo.h>
+#include <linux/serial.h>
 
 #include "u_serial.h"
 
@@ -126,6 +127,7 @@ struct gs_port {
        wait_queue_head_t       close_wait;
        bool                    suspended;      /* port suspended */
        bool                    start_delayed;  /* delay start when suspended */
+       struct async_icount     icount;
 
        /* REVISIT this state ... */
        struct usb_cdc_line_coding port_line_coding;    /* 8-N-1 etc */
@@ -257,6 +259,7 @@ __acquires(&port->port_lock)
                        break;
                }
                do_tty_wake = true;
+               port->icount.tx += len;
 
                req->length = len;
                list_del(&req->list);
@@ -408,6 +411,7 @@ static void gs_rx_push(struct work_struct *work)
                                size -= n;
                        }
 
+                       port->icount.rx += size;
                        count = tty_insert_flip_string(&port->port, packet,
                                        size);
                        if (count)
@@ -851,6 +855,23 @@ static int gs_break_ctl(struct tty_struct *tty, int duration)
        return status;
 }
 
+static int gs_get_icount(struct tty_struct *tty,
+                        struct serial_icounter_struct *icount)
+{
+       struct gs_port *port = tty->driver_data;
+       struct async_icount cnow;
+       unsigned long flags;
+
+       spin_lock_irqsave(&port->port_lock, flags);
+       cnow = port->icount;
+       spin_unlock_irqrestore(&port->port_lock, flags);
+
+       icount->rx = cnow.rx;
+       icount->tx = cnow.tx;
+
+       return 0;
+}
+
 static const struct tty_operations gs_tty_ops = {
        .open =                 gs_open,
        .close =                gs_close,
@@ -861,6 +882,7 @@ static const struct tty_operations gs_tty_ops = {
        .chars_in_buffer =      gs_chars_in_buffer,
        .unthrottle =           gs_unthrottle,
        .break_ctl =            gs_break_ctl,
+       .get_icount =           gs_get_icount,
 };
 
 /*-------------------------------------------------------------------------*/