diff options
Diffstat (limited to 'drivers/usb/gadget/function/u_serial.c')
| -rw-r--r-- | drivers/usb/gadget/function/u_serial.c | 61 |
1 files changed, 56 insertions, 5 deletions
diff --git a/drivers/usb/gadget/function/u_serial.c b/drivers/usb/gadget/function/u_serial.c index bc143a86c2dd..ab544f6824be 100644 --- a/drivers/usb/gadget/function/u_serial.c +++ b/drivers/usb/gadget/function/u_serial.c @@ -21,6 +21,7 @@ #include <linux/tty.h> #include <linux/tty_flip.h> #include <linux/slab.h> +#include <linux/string_choices.h> #include <linux/export.h> #include <linux/module.h> #include <linux/console.h> @@ -591,6 +592,17 @@ static int gs_start_io(struct gs_port *port) return status; } +static int gserial_wakeup_host(struct gserial *gser) +{ + struct usb_function *func = &gser->func; + struct usb_gadget *gadget = func->config->cdev->gadget; + + if (func->func_suspended) + return usb_func_wakeup(func); + else + return usb_gadget_wakeup(gadget); +} + /*-------------------------------------------------------------------------*/ /* TTY Driver */ @@ -745,6 +757,8 @@ static ssize_t gs_write(struct tty_struct *tty, const u8 *buf, size_t count) { struct gs_port *port = tty->driver_data; unsigned long flags; + int ret = 0; + struct gserial *gser = port->port_usb; pr_vdebug("gs_write: ttyGS%d (%p) writing %zu bytes\n", port->port_num, tty, count); @@ -752,6 +766,17 @@ static ssize_t gs_write(struct tty_struct *tty, const u8 *buf, size_t count) spin_lock_irqsave(&port->port_lock, flags); if (count) count = kfifo_in(&port->port_write_buf, buf, count); + + if (port->suspended) { + spin_unlock_irqrestore(&port->port_lock, flags); + ret = gserial_wakeup_host(gser); + if (ret) { + pr_debug("ttyGS%d: Remote wakeup failed:%d\n", port->port_num, ret); + return count; + } + spin_lock_irqsave(&port->port_lock, flags); + } + /* treat count == 0 as flush_chars() */ if (port->port_usb) gs_start_tx(port); @@ -780,10 +805,22 @@ static void gs_flush_chars(struct tty_struct *tty) { struct gs_port *port = tty->driver_data; unsigned long flags; + int ret = 0; + struct gserial *gser = port->port_usb; pr_vdebug("gs_flush_chars: (%d,%p)\n", port->port_num, tty); spin_lock_irqsave(&port->port_lock, flags); + if (port->suspended) { + spin_unlock_irqrestore(&port->port_lock, flags); + ret = gserial_wakeup_host(gser); + if (ret) { + pr_debug("ttyGS%d: Remote wakeup failed:%d\n", port->port_num, ret); + return; + } + spin_lock_irqsave(&port->port_lock, flags); + } + if (port->port_usb) gs_start_tx(port); spin_unlock_irqrestore(&port->port_lock, flags); @@ -1420,10 +1457,6 @@ void gserial_disconnect(struct gserial *gser) /* REVISIT as above: how best to track this? */ port->port_line_coding = gser->port_line_coding; - /* disable endpoints, aborting down any active I/O */ - usb_ep_disable(gser->out); - usb_ep_disable(gser->in); - port->port_usb = NULL; gser->ioport = NULL; if (port->port.count > 0) { @@ -1435,6 +1468,10 @@ void gserial_disconnect(struct gserial *gser) spin_unlock(&port->port_lock); spin_unlock_irqrestore(&serial_port_lock, flags); + /* disable endpoints, aborting down any active I/O */ + usb_ep_disable(gser->out); + usb_ep_disable(gser->in); + /* finally, free any unused/unusable I/O buffers */ spin_lock_irqsave(&port->port_lock, flags); if (port->port.count == 0) @@ -1463,6 +1500,20 @@ void gserial_suspend(struct gserial *gser) return; } + if (port->write_busy || port->write_started) { + /* Wakeup to host if there are ongoing transfers */ + spin_unlock_irqrestore(&serial_port_lock, flags); + if (!gserial_wakeup_host(gser)) + return; + + /* Check if port is valid after acquiring lock back */ + spin_lock_irqsave(&serial_port_lock, flags); + if (!port) { + spin_unlock_irqrestore(&serial_port_lock, flags); + return; + } + } + spin_lock(&port->port_lock); spin_unlock(&serial_port_lock); port->suspended = true; @@ -1545,7 +1596,7 @@ static int __init userial_init(void) pr_debug("%s: registered %d ttyGS* device%s\n", __func__, MAX_U_SERIAL_PORTS, - (MAX_U_SERIAL_PORTS == 1) ? "" : "s"); + str_plural(MAX_U_SERIAL_PORTS)); return status; fail: |