1 files changed, 658 insertions, 0 deletions

diff --git a/drivers/usb/serial/usb_wwan.c b/drivers/usb/serial/usb_wwan.c
new file mode 100644
index 000000000..0017f6e96
--- /dev/null
+++ b/drivers/usb/serial/usb_wwan.c
@@ -0,0 +1,658 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+  USB Driver layer for GSM modems
+
+  Copyright (C) 2005  Matthias Urlichs <smurf@smurf.noris.de>
+
+  Portions copied from the Keyspan driver by Hugh Blemings <hugh@blemings.org>
+
+  History: see the git log.
+
+  Work sponsored by: Sigos GmbH, Germany <info@sigos.de>
+
+  This driver exists because the "normal" serial driver doesn't work too well
+  with GSM modems. Issues:
+  - data loss -- one single Receive URB is not nearly enough
+  - controlling the baud rate doesn't make sense
+*/
+
+#define DRIVER_AUTHOR "Matthias Urlichs <smurf@smurf.noris.de>"
+#define DRIVER_DESC "USB Driver for GSM modems"
+
+#include <linux/kernel.h>
+#include <linux/jiffies.h>
+#include <linux/errno.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/module.h>
+#include <linux/bitops.h>
+#include <linux/uaccess.h>
+#include <linux/usb.h>
+#include <linux/usb/cdc.h>
+#include <linux/usb/serial.h>
+#include <linux/serial.h>
+#include "usb-wwan.h"
+
+/*
+ * Generate DTR/RTS signals on the port using the SET_CONTROL_LINE_STATE request
+ * in CDC ACM.
+ */
+static int usb_wwan_send_setup(struct usb_serial_port *port)
+{
+	struct usb_serial *serial = port->serial;
+	struct usb_wwan_port_private *portdata;
+	int val = 0;
+	int ifnum;
+	int res;
+
+	portdata = usb_get_serial_port_data(port);
+
+	if (portdata->dtr_state)
+		val |= USB_CDC_CTRL_DTR;
+	if (portdata->rts_state)
+		val |= USB_CDC_CTRL_RTS;
+
+	ifnum = serial->interface->cur_altsetting->desc.bInterfaceNumber;
+
+	res = usb_autopm_get_interface(serial->interface);
+	if (res)
+		return res;
+
+	res = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+				USB_CDC_REQ_SET_CONTROL_LINE_STATE,
+				USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+				val, ifnum, NULL, 0, USB_CTRL_SET_TIMEOUT);
+
+	usb_autopm_put_interface(port->serial->interface);
+
+	return res;
+}
+
+void usb_wwan_dtr_rts(struct usb_serial_port *port, int on)
+{
+	struct usb_wwan_port_private *portdata;
+	struct usb_wwan_intf_private *intfdata;
+
+	intfdata = usb_get_serial_data(port->serial);
+
+	if (!intfdata->use_send_setup)
+		return;
+
+	portdata = usb_get_serial_port_data(port);
+	/* FIXME: locking */
+	portdata->rts_state = on;
+	portdata->dtr_state = on;
+
+	usb_wwan_send_setup(port);
+}
+EXPORT_SYMBOL(usb_wwan_dtr_rts);
+
+int usb_wwan_tiocmget(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	unsigned int value;
+	struct usb_wwan_port_private *portdata;
+
+	portdata = usb_get_serial_port_data(port);
+
+	value = ((portdata->rts_state) ? TIOCM_RTS : 0) |
+	    ((portdata->dtr_state) ? TIOCM_DTR : 0) |
+	    ((portdata->cts_state) ? TIOCM_CTS : 0) |
+	    ((portdata->dsr_state) ? TIOCM_DSR : 0) |
+	    ((portdata->dcd_state) ? TIOCM_CAR : 0) |
+	    ((portdata->ri_state) ? TIOCM_RNG : 0);
+
+	return value;
+}
+EXPORT_SYMBOL(usb_wwan_tiocmget);
+
+int usb_wwan_tiocmset(struct tty_struct *tty,
+		      unsigned int set, unsigned int clear)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct usb_wwan_port_private *portdata;
+	struct usb_wwan_intf_private *intfdata;
+
+	portdata = usb_get_serial_port_data(port);
+	intfdata = usb_get_serial_data(port->serial);
+
+	if (!intfdata->use_send_setup)
+		return -EINVAL;
+
+	/* FIXME: what locks portdata fields ? */
+	if (set & TIOCM_RTS)
+		portdata->rts_state = 1;
+	if (set & TIOCM_DTR)
+		portdata->dtr_state = 1;
+
+	if (clear & TIOCM_RTS)
+		portdata->rts_state = 0;
+	if (clear & TIOCM_DTR)
+		portdata->dtr_state = 0;
+	return usb_wwan_send_setup(port);
+}
+EXPORT_SYMBOL(usb_wwan_tiocmset);
+
+int usb_wwan_write(struct tty_struct *tty, struct usb_serial_port *port,
+		   const unsigned char *buf, int count)
+{
+	struct usb_wwan_port_private *portdata;
+	struct usb_wwan_intf_private *intfdata;
+	int i;
+	int left, todo;
+	struct urb *this_urb = NULL;	/* spurious */
+	int err;
+	unsigned long flags;
+
+	portdata = usb_get_serial_port_data(port);
+	intfdata = usb_get_serial_data(port->serial);
+
+	dev_dbg(&port->dev, "%s: write (%d chars)\n", __func__, count);
+
+	left = count;
+	for (i = 0; left > 0 && i < N_OUT_URB; i++) {
+		todo = left;
+		if (todo > OUT_BUFLEN)
+			todo = OUT_BUFLEN;
+
+		this_urb = portdata->out_urbs[i];
+		if (test_and_set_bit(i, &portdata->out_busy)) {
+			if (time_before(jiffies,
+					portdata->tx_start_time[i] + 10 * HZ))
+				continue;
+			usb_unlink_urb(this_urb);
+			continue;
+		}
+		dev_dbg(&port->dev, "%s: endpoint %d buf %d\n", __func__,
+			usb_pipeendpoint(this_urb->pipe), i);
+
+		err = usb_autopm_get_interface_async(port->serial->interface);
+		if (err < 0) {
+			clear_bit(i, &portdata->out_busy);
+			break;
+		}
+
+		/* send the data */
+		memcpy(this_urb->transfer_buffer, buf, todo);
+		this_urb->transfer_buffer_length = todo;
+
+		spin_lock_irqsave(&intfdata->susp_lock, flags);
+		if (intfdata->suspended) {
+			usb_anchor_urb(this_urb, &portdata->delayed);
+			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
+		} else {
+			intfdata->in_flight++;
+			spin_unlock_irqrestore(&intfdata->susp_lock, flags);
+			err = usb_submit_urb(this_urb, GFP_ATOMIC);
+			if (err) {
+				dev_err(&port->dev,
+					"%s: submit urb %d failed: %d\n",
+					__func__, i, err);
+				clear_bit(i, &portdata->out_busy);
+				spin_lock_irqsave(&intfdata->susp_lock, flags);
+				intfdata->in_flight--;
+				spin_unlock_irqrestore(&intfdata->susp_lock,
+						       flags);
+				usb_autopm_put_interface_async(port->serial->interface);
+				break;
+			}
+		}
+
+		portdata->tx_start_time[i] = jiffies;
+		buf += todo;
+		left -= todo;
+	}
+
+	count -= left;
+	dev_dbg(&port->dev, "%s: wrote (did %d)\n", __func__, count);
+	return count;
+}
+EXPORT_SYMBOL(usb_wwan_write);
+
+static void usb_wwan_indat_callback(struct urb *urb)
+{
+	int err;
+	int endpoint;
+	struct usb_serial_port *port;
+	struct device *dev;
+	unsigned char *data = urb->transfer_buffer;
+	int status = urb->status;
+
+	endpoint = usb_pipeendpoint(urb->pipe);
+	port = urb->context;
+	dev = &port->dev;
+
+	if (status) {
+		dev_dbg(dev, "%s: nonzero status: %d on endpoint %02x.\n",
+			__func__, status, endpoint);
+
+		/* don't resubmit on fatal errors */
+		if (status == -ESHUTDOWN || status == -ENOENT)
+			return;
+	} else {
+		if (urb->actual_length) {
+			tty_insert_flip_string(&port->port, data,
+					urb->actual_length);
+			tty_flip_buffer_push(&port->port);
+		} else
+			dev_dbg(dev, "%s: empty read urb received\n", __func__);
+	}
+	/* Resubmit urb so we continue receiving */
+	err = usb_submit_urb(urb, GFP_ATOMIC);
+	if (err) {
+		if (err != -EPERM && err != -ENODEV) {
+			dev_err(dev, "%s: resubmit read urb failed. (%d)\n",
+				__func__, err);
+			/* busy also in error unless we are killed */
+			usb_mark_last_busy(port->serial->dev);
+		}
+	} else {
+		usb_mark_last_busy(port->serial->dev);
+	}
+}
+
+static void usb_wwan_outdat_callback(struct urb *urb)
+{
+	struct usb_serial_port *port;
+	struct usb_wwan_port_private *portdata;
+	struct usb_wwan_intf_private *intfdata;
+	unsigned long flags;
+	int i;
+
+	port = urb->context;
+	intfdata = usb_get_serial_data(port->serial);
+
+	usb_serial_port_softint(port);
+	usb_autopm_put_interface_async(port->serial->interface);
+	portdata = usb_get_serial_port_data(port);
+	spin_lock_irqsave(&intfdata->susp_lock, flags);
+	intfdata->in_flight--;
+	spin_unlock_irqrestore(&intfdata->susp_lock, flags);
+
+	for (i = 0; i < N_OUT_URB; ++i) {
+		if (portdata->out_urbs[i] == urb) {
+			smp_mb__before_atomic();
+			clear_bit(i, &portdata->out_busy);
+			break;
+		}
+	}
+}
+
+unsigned int usb_wwan_write_room(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct usb_wwan_port_private *portdata;
+	int i;
+	unsigned int data_len = 0;
+	struct urb *this_urb;
+
+	portdata = usb_get_serial_port_data(port);
+
+	for (i = 0; i < N_OUT_URB; i++) {
+		this_urb = portdata->out_urbs[i];
+		if (this_urb && !test_bit(i, &portdata->out_busy))
+			data_len += OUT_BUFLEN;
+	}
+
+	dev_dbg(&port->dev, "%s: %u\n", __func__, data_len);
+	return data_len;
+}
+EXPORT_SYMBOL(usb_wwan_write_room);
+
+unsigned int usb_wwan_chars_in_buffer(struct tty_struct *tty)
+{
+	struct usb_serial_port *port = tty->driver_data;
+	struct usb_wwan_port_private *portdata;
+	int i;
+	unsigned int data_len = 0;
+	struct urb *this_urb;
+
+	portdata = usb_get_serial_port_data(port);
+
+	for (i = 0; i < N_OUT_URB; i++) {
+		this_urb = portdata->out_urbs[i];
+		/* FIXME: This locking is insufficient as this_urb may
+		   go unused during the test */
+		if (this_urb && test_bit(i, &portdata->out_busy))
+			data_len += this_urb->transfer_buffer_length;
+	}
+	dev_dbg(&port->dev, "%s: %u\n", __func__, data_len);
+	return data_len;
+}
+EXPORT_SYMBOL(usb_wwan_chars_in_buffer);
+
+int usb_wwan_open(struct tty_struct *tty, struct usb_serial_port *port)
+{
+	struct usb_wwan_port_private *portdata;
+	struct usb_wwan_intf_private *intfdata;
+	struct usb_serial *serial = port->serial;
+	int i, err;
+	struct urb *urb;
+
+	portdata = usb_get_serial_port_data(port);
+	intfdata = usb_get_serial_data(serial);
+
+	if (port->interrupt_in_urb) {
+		err = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
+		if (err) {
+			dev_err(&port->dev, "%s: submit int urb failed: %d\n",
+				__func__, err);
+		}
+	}
+
+	/* Start reading from the IN endpoint */
+	for (i = 0; i < N_IN_URB; i++) {
+		urb = portdata->in_urbs[i];
+		if (!urb)
+			continue;
+		err = usb_submit_urb(urb, GFP_KERNEL);
+		if (err) {
+			dev_err(&port->dev,
+				"%s: submit read urb %d failed: %d\n",
+				__func__, i, err);
+		}
+	}
+
+	spin_lock_irq(&intfdata->susp_lock);
+	if (++intfdata->open_ports == 1)
+		serial->interface->needs_remote_wakeup = 1;
+	spin_unlock_irq(&intfdata->susp_lock);
+	/* this balances a get in the generic USB serial code */
+	usb_autopm_put_interface(serial->interface);
+
+	return 0;
+}
+EXPORT_SYMBOL(usb_wwan_open);
+
+static void unbusy_queued_urb(struct urb *urb,
+					struct usb_wwan_port_private *portdata)
+{
+	int i;
+
+	for (i = 0; i < N_OUT_URB; i++) {
+		if (urb == portdata->out_urbs[i]) {
+			clear_bit(i, &portdata->out_busy);
+			break;
+		}
+	}
+}
+
+void usb_wwan_close(struct usb_serial_port *port)
+{
+	int i;
+	struct usb_serial *serial = port->serial;
+	struct usb_wwan_port_private *portdata;
+	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
+	struct urb *urb;
+
+	portdata = usb_get_serial_port_data(port);
+
+	/*
+	 * Need to take susp_lock to make sure port is not already being
+	 * resumed, but no need to hold it due to the tty-port initialized
+	 * flag.
+	 */
+	spin_lock_irq(&intfdata->susp_lock);
+	if (--intfdata->open_ports == 0)
+		serial->interface->needs_remote_wakeup = 0;
+	spin_unlock_irq(&intfdata->susp_lock);
+
+	for (;;) {
+		urb = usb_get_from_anchor(&portdata->delayed);
+		if (!urb)
+			break;
+		unbusy_queued_urb(urb, portdata);
+		usb_autopm_put_interface_async(serial->interface);
+	}
+
+	for (i = 0; i < N_IN_URB; i++)
+		usb_kill_urb(portdata->in_urbs[i]);
+	for (i = 0; i < N_OUT_URB; i++)
+		usb_kill_urb(portdata->out_urbs[i]);
+	usb_kill_urb(port->interrupt_in_urb);
+
+	usb_autopm_get_interface_no_resume(serial->interface);
+}
+EXPORT_SYMBOL(usb_wwan_close);
+
+static struct urb *usb_wwan_setup_urb(struct usb_serial_port *port,
+				      int endpoint,
+				      int dir, void *ctx, char *buf, int len,
+				      void (*callback) (struct urb *))
+{
+	struct usb_serial *serial = port->serial;
+	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
+	struct urb *urb;
+
+	urb = usb_alloc_urb(0, GFP_KERNEL);	/* No ISO */
+	if (!urb)
+		return NULL;
+
+	usb_fill_bulk_urb(urb, serial->dev,
+			  usb_sndbulkpipe(serial->dev, endpoint) | dir,
+			  buf, len, callback, ctx);
+
+	if (intfdata->use_zlp && dir == USB_DIR_OUT)
+		urb->transfer_flags |= URB_ZERO_PACKET;
+
+	return urb;
+}
+
+int usb_wwan_port_probe(struct usb_serial_port *port)
+{
+	struct usb_wwan_port_private *portdata;
+	struct urb *urb;
+	u8 *buffer;
+	int i;
+
+	if (!port->bulk_in_size || !port->bulk_out_size)
+		return -ENODEV;
+
+	portdata = kzalloc(sizeof(*portdata), GFP_KERNEL);
+	if (!portdata)
+		return -ENOMEM;
+
+	init_usb_anchor(&portdata->delayed);
+
+	for (i = 0; i < N_IN_URB; i++) {
+		buffer = (u8 *)__get_free_page(GFP_KERNEL);
+		if (!buffer)
+			goto bail_out_error;
+		portdata->in_buffer[i] = buffer;
+
+		urb = usb_wwan_setup_urb(port, port->bulk_in_endpointAddress,
+						USB_DIR_IN, port,
+						buffer, IN_BUFLEN,
+						usb_wwan_indat_callback);
+		portdata->in_urbs[i] = urb;
+	}
+
+	for (i = 0; i < N_OUT_URB; i++) {
+		buffer = kmalloc(OUT_BUFLEN, GFP_KERNEL);
+		if (!buffer)
+			goto bail_out_error2;
+		portdata->out_buffer[i] = buffer;
+
+		urb = usb_wwan_setup_urb(port, port->bulk_out_endpointAddress,
+						USB_DIR_OUT, port,
+						buffer, OUT_BUFLEN,
+						usb_wwan_outdat_callback);
+		portdata->out_urbs[i] = urb;
+	}
+
+	usb_set_serial_port_data(port, portdata);
+
+	return 0;
+
+bail_out_error2:
+	for (i = 0; i < N_OUT_URB; i++) {
+		usb_free_urb(portdata->out_urbs[i]);
+		kfree(portdata->out_buffer[i]);
+	}
+bail_out_error:
+	for (i = 0; i < N_IN_URB; i++) {
+		usb_free_urb(portdata->in_urbs[i]);
+		free_page((unsigned long)portdata->in_buffer[i]);
+	}
+	kfree(portdata);
+
+	return -ENOMEM;
+}
+EXPORT_SYMBOL_GPL(usb_wwan_port_probe);
+
+void usb_wwan_port_remove(struct usb_serial_port *port)
+{
+	int i;
+	struct usb_wwan_port_private *portdata;
+
+	portdata = usb_get_serial_port_data(port);
+	usb_set_serial_port_data(port, NULL);
+
+	for (i = 0; i < N_IN_URB; i++) {
+		usb_free_urb(portdata->in_urbs[i]);
+		free_page((unsigned long)portdata->in_buffer[i]);
+	}
+	for (i = 0; i < N_OUT_URB; i++) {
+		usb_free_urb(portdata->out_urbs[i]);
+		kfree(portdata->out_buffer[i]);
+	}
+
+	kfree(portdata);
+}
+EXPORT_SYMBOL(usb_wwan_port_remove);
+
+#ifdef CONFIG_PM
+static void stop_urbs(struct usb_serial *serial)
+{
+	int i, j;
+	struct usb_serial_port *port;
+	struct usb_wwan_port_private *portdata;
+
+	for (i = 0; i < serial->num_ports; ++i) {
+		port = serial->port[i];
+		portdata = usb_get_serial_port_data(port);
+		if (!portdata)
+			continue;
+		for (j = 0; j < N_IN_URB; j++)
+			usb_kill_urb(portdata->in_urbs[j]);
+		for (j = 0; j < N_OUT_URB; j++)
+			usb_kill_urb(portdata->out_urbs[j]);
+		usb_kill_urb(port->interrupt_in_urb);
+	}
+}
+
+int usb_wwan_suspend(struct usb_serial *serial, pm_message_t message)
+{
+	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
+
+	spin_lock_irq(&intfdata->susp_lock);
+	if (PMSG_IS_AUTO(message)) {
+		if (intfdata->in_flight) {
+			spin_unlock_irq(&intfdata->susp_lock);
+			return -EBUSY;
+		}
+	}
+	intfdata->suspended = 1;
+	spin_unlock_irq(&intfdata->susp_lock);
+
+	stop_urbs(serial);
+
+	return 0;
+}
+EXPORT_SYMBOL(usb_wwan_suspend);
+
+/* Caller must hold susp_lock. */
+static int usb_wwan_submit_delayed_urbs(struct usb_serial_port *port)
+{
+	struct usb_serial *serial = port->serial;
+	struct usb_wwan_intf_private *data = usb_get_serial_data(serial);
+	struct usb_wwan_port_private *portdata;
+	struct urb *urb;
+	int err_count = 0;
+	int err;
+
+	portdata = usb_get_serial_port_data(port);
+
+	for (;;) {
+		urb = usb_get_from_anchor(&portdata->delayed);
+		if (!urb)
+			break;
+
+		err = usb_submit_urb(urb, GFP_ATOMIC);
+		if (err) {
+			dev_err(&port->dev, "%s: submit urb failed: %d\n",
+					__func__, err);
+			err_count++;
+			unbusy_queued_urb(urb, portdata);
+			usb_autopm_put_interface_async(serial->interface);
+			continue;
+		}
+		data->in_flight++;
+	}
+
+	if (err_count)
+		return -EIO;
+
+	return 0;
+}
+
+int usb_wwan_resume(struct usb_serial *serial)
+{
+	int i, j;
+	struct usb_serial_port *port;
+	struct usb_wwan_intf_private *intfdata = usb_get_serial_data(serial);
+	struct usb_wwan_port_private *portdata;
+	struct urb *urb;
+	int err;
+	int err_count = 0;
+
+	spin_lock_irq(&intfdata->susp_lock);
+	for (i = 0; i < serial->num_ports; i++) {
+		port = serial->port[i];
+
+		if (!tty_port_initialized(&port->port))
+			continue;
+
+		portdata = usb_get_serial_port_data(port);
+
+		if (port->interrupt_in_urb) {
+			err = usb_submit_urb(port->interrupt_in_urb,
+					GFP_ATOMIC);
+			if (err) {
+				dev_err(&port->dev,
+					"%s: submit int urb failed: %d\n",
+					__func__, err);
+				err_count++;
+			}
+		}
+
+		err = usb_wwan_submit_delayed_urbs(port);
+		if (err)
+			err_count++;
+
+		for (j = 0; j < N_IN_URB; j++) {
+			urb = portdata->in_urbs[j];
+			err = usb_submit_urb(urb, GFP_ATOMIC);
+			if (err < 0) {
+				dev_err(&port->dev,
+					"%s: submit read urb %d failed: %d\n",
+					__func__, i, err);
+				err_count++;
+			}
+		}
+	}
+	intfdata->suspended = 0;
+	spin_unlock_irq(&intfdata->susp_lock);
+
+	if (err_count)
+		return -EIO;
+
+	return 0;
+}
+EXPORT_SYMBOL(usb_wwan_resume);
+#endif
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL v2");