Subject: [PATCH 002/002] USB: serial: sierra driver autosuspend support
From: Elina Pasheva <epasheva@xxxxxxxxxxxxxxxxxx>
This patch [PATCH 002/002] addresses Oliver Neukum's comments for the similar
patch we submitted in the spring:
[PATCH 002/002] dealing with autosuspend support:
- Renamed module parameter "suspend_support" to "support_autopm" for clarity
- Implemented anchor interface on the transmit path so that the Tx urbs are
kept track of and are released during suspend
- Added sierra_suspend(), sierra_resume() functions and support.
- Moved sierra_device structure at the bottom
- Added entries for suspend and resume interfaces to sierra_device structure.
- Added new device attribute "suspend_status" which reflects the power state
for each device served by the sierra driver.
- Added provisions to enable debugging by using DEBUG definition
- Version number set to 1.7.2 to match our repository.
Signed-off-by: Elina Pasheva <epasheva@xxxxxxxxxxxxxxxxxx>
---
drivers/usb/serial/sierra.c | 150 ++++++++++++++++++++++++++++++----
1 file changed, 135 insertions(+), 15 deletions(-)
--- a/drivers/usb/serial/sierra.c
+++ b/drivers/usb/serial/sierra.c
@@ -16,8 +16,9 @@
Portions based on the option driver by Matthias Urlichs <smurf@xxxxxxxxxxxxxx>
Whom based his on the Keyspan driver by Hugh Blemings <hugh@xxxxxxxxxxxx>
*/
-
-#define DRIVER_VERSION "v.1.3.7"
+/* Uncomment to log function calls */
+/* #define DEBUG */
+#define DRIVER_VERSION "v.1.7.2"
#define DRIVER_AUTHOR "Kevin Lloyd, Elina Pasheva, Matthew Safar, Rory Filer"
#define DRIVER_DESC "USB Driver for Sierra Wireless USB modems"
@@ -44,6 +45,11 @@
static int debug;
static int nmea;
+static int support_autopm;
+
+/* sysfs attributes */
+static int sierra_create_sysfs_attrs(struct usb_serial_port *port);
+/* Note: attribute created for each port; removed on disconnect */
/* Used in interface blacklisting */
struct sierra_iface_info {
@@ -257,18 +263,13 @@ static struct usb_device_id id_table []
};
MODULE_DEVICE_TABLE(usb, id_table);
-static struct usb_driver sierra_driver = {
- .name = "sierra",
- .probe = usb_serial_probe,
- .disconnect = usb_serial_disconnect,
- .id_table = id_table,
- .no_dynamic_id = 1,
-};
-
struct sierra_port_private {
spinlock_t lock; /* lock the structure */
int outstanding_urbs; /* number of out urbs in flight */
-
+ struct usb_anchor submitted; /* in case we need to retract our
+ * submissions */
+ int suspend_status; /* indicates whether device power has been
+ * suspended */
/* Input endpoints and buffers for this port */
struct urb *in_urbs[N_IN_URB];
@@ -386,6 +387,28 @@ static void sierra_release_urb(struct ur
}
}
+/* Sysfs Attributes */
+
+static ssize_t show_suspend_status(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct usb_serial_port *port;
+ struct sierra_port_private *portdata;
+
+ port = to_usb_serial_port(dev);
+ portdata = usb_get_serial_port_data(port);
+
+ return snprintf(buf, 4096, "%i\n", portdata->suspend_status);
+}
+
+static DEVICE_ATTR(suspend_status, S_IWUSR | S_IRUGO, show_suspend_status,
+ NULL);
+
+static int sierra_create_sysfs_attrs(struct usb_serial_port *port)
+{
+ return device_create_file(&port->dev, &dev_attr_suspend_status);
+}
+
static void sierra_outdat_callback(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
@@ -467,21 +490,24 @@ static int sierra_write(struct tty_struc
/* Handle the need to send a zero length packet */
urb->transfer_flags |= URB_ZERO_PACKET;
+ usb_anchor_urb(urb, &portdata->submitted);
/* send it down the pipe */
retval = usb_submit_urb(urb, GFP_ATOMIC);
if (retval) {
dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed "
"with status = %d\n", __func__, retval);
- goto error;
+ goto error_anchor;
}
- /* we are done with this urb, so let the host driver
- * really free it when it is finished with it */
+ /* release our reference to this urb, the USB core will eventually
+ * free it entirely */
usb_free_urb(urb);
return writesize;
-error:
+
+error_anchor:
+ usb_unanchor_urb(urb);
usb_free_urb(urb);
error_no_urb:
kfree(buffer);
@@ -711,6 +737,7 @@ static void sierra_close(struct usb_seri
int i;
struct usb_serial *serial = port->serial;
struct sierra_port_private *portdata;
+ int time;
dev_dbg(&port->dev, "%s\n", __func__);
portdata = usb_get_serial_port_data(port);
@@ -731,6 +758,11 @@ static void sierra_close(struct usb_seri
sierra_release_urb(portdata->in_urbs[i]);
portdata->in_urbs[i] = NULL;
}
+
+ time = usb_wait_anchor_empty_timeout(&portdata->submitted,
+ 1000);
+ if (!time)
+ usb_kill_anchored_urbs(&portdata->submitted);
}
}
@@ -819,8 +851,19 @@ static int sierra_startup(struct usb_ser
return -ENOMEM;
}
spin_lock_init(&portdata->lock);
+ init_usb_anchor(&portdata->submitted);
+ portdata->suspend_status = 0;
/* Set the port private data pointer */
usb_set_serial_port_data(port, portdata);
+ if (support_autopm == 0) {
+ /* When the device does not support suspend condition
+ * indicate the device is busy */
+ usb_autopm_disable(serial->interface);
+ } else {
+ /* When the device does support autosuspend
+ * indicate the device is not busy */
+ usb_autopm_enable(serial->interface);
+ }
}
return 0;
@@ -841,11 +884,82 @@ static void sierra_disconnect(struct usb
portdata = usb_get_serial_port_data(port);
if (!portdata)
continue;
+ portdata->suspend_status = 0;
+ device_remove_file(&port->dev, &dev_attr_suspend_status);
+
kfree(portdata);
usb_set_serial_port_data(port, NULL);
}
}
+int sierra_suspend(struct usb_serial *serial, pm_message_t message)
+{
+ int i;
+ struct usb_serial_port *port;
+ struct sierra_port_private *portdata;
+ unsigned long flags;
+ int time;
+
+ dev_dbg(&serial->dev->dev, "%s\n", __func__);
+
+ for (i = 0; i < serial->num_ports; ++i) {
+ port = serial->port[i];
+ if (!port)
+ continue;
+ portdata = usb_get_serial_port_data(port);
+ if (!portdata)
+ continue;
+ /* indicate suspended power mode */
+ portdata->suspend_status = 1;
+ sierra_stop_rx_urbs(port);
+ /* release tx urbs */
+ time = usb_wait_anchor_empty_timeout(&portdata->submitted,
+ 1000);
+ if (!time) {
+ usb_kill_anchored_urbs(&portdata->submitted);
+ spin_lock_irqsave(&portdata->lock, flags);
+ /* set outstanding tx urbs counter to 0 */
+ portdata->outstanding_urbs = 0;
+ spin_unlock_irqrestore(&portdata->lock, flags);
+ }
+ } /* end for loop */
+ return 0;
+}
+
+int sierra_resume(struct usb_serial *serial)
+{
+ int i;
+ struct usb_serial_port *port;
+ struct sierra_port_private *portdata;
+
+ dev_dbg(&serial->dev->dev, "%s\n", __func__);
+
+ for (i = 0; i < serial->num_ports ; i++) {
+ port = serial->port[i];
+ if (!port)
+ continue;
+ portdata = usb_get_serial_port_data(port);
+ if (!portdata)
+ continue;
+ sierra_submit_rx_urbs(port, GFP_NOIO);
+ /* indicate non-suspended power mode */
+ portdata->suspend_status = 0;
+ }
+ return 0;
+}
+
+static struct usb_driver sierra_driver = {
+ .name = "sierra",
+ .probe = usb_serial_probe,
+ .disconnect = usb_serial_disconnect,
+ .suspend = usb_serial_suspend,
+ .resume = usb_serial_resume,
+ .id_table = id_table,
+
+ .no_dynamic_id = 1,
+ .supports_autosuspend = 1,
+};
+
static struct usb_serial_driver sierra_device = {
.driver = {
.owner = THIS_MODULE,
@@ -866,7 +980,10 @@ static struct usb_serial_driver sierra_d
.tiocmset = sierra_tiocmset,
.attach = sierra_startup,
.disconnect = sierra_disconnect,
+ .port_probe = sierra_create_sysfs_attrs,
.read_int_callback = sierra_instat_callback,
+ .suspend = sierra_suspend,
+ .resume = sierra_resume,
};
/* Functions used by new usb-serial code. */
@@ -912,3 +1029,6 @@ MODULE_PARM_DESC(nmea, "NMEA streaming")
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug messages");
+
+module_param(support_autopm, bool, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(support_autopm, "Device auto suspend support");
--
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