usb_serial: API all change

USB serial likes to use port->tty back pointers for the real work it does and
to do so without any actual locking. Unfortunately when you consider hangup
events, hangup/parallel reopen or even worse hangup followed by parallel close
events the tty->port and port->tty pointers are not guaranteed to be the same
as port->tty is the active tty while tty->port is the port the tty may or
may not still be attached to.

So rework the entire API to pass the tty struct. For console cases we need
to pass both for now. This shows up multiple drivers that immediately crash
with USB console some of which have been fixed in the process.

Longer term we need a proper tty as console abstraction

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 101 insertions, 102 deletions

diff --git a/drivers/usb/serial/ti_usb_3410_5052.c b/drivers/usb/serial/ti_usb_3410_5052.c
index a26a629dfc4f..48831a755fc1 100644
--- a/drivers/usb/serial/ti_usb_3410_5052.c
+++ b/drivers/usb/serial/ti_usb_3410_5052.c
@@ -70,6 +70,7 @@
 
 #include <linux/kernel.h>
 #include <linux/errno.h>
+#include <linux/firmware.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/tty.h>
@@ -149,21 +150,23 @@ struct ti_device {
 
 static int ti_startup(struct usb_serial *serial);
 static void ti_shutdown(struct usb_serial *serial);
-static int ti_open(struct usb_serial_port *port, struct file *file);
-static void ti_close(struct usb_serial_port *port, struct file *file);
-static int ti_write(struct usb_serial_port *port, const unsigned char *data,
-	int count);
-static int ti_write_room(struct usb_serial_port *port);
-static int ti_chars_in_buffer(struct usb_serial_port *port);
-static void ti_throttle(struct usb_serial_port *port);
-static void ti_unthrottle(struct usb_serial_port *port);
-static int ti_ioctl(struct usb_serial_port *port, struct file *file, unsigned int cmd, unsigned long arg);
-static void ti_set_termios(struct usb_serial_port *port,
+static int ti_open(struct tty_struct *tty, struct usb_serial_port *port,
+				struct file *file);
+static void ti_close(struct tty_struct *tty, struct usb_serial_port *port,
+				struct file *file);
+static int ti_write(struct tty_struct *tty, struct usb_serial_port *port,
+				const unsigned char *data, int count);
+static int ti_write_room(struct tty_struct *tty);
+static int ti_chars_in_buffer(struct tty_struct *tty);
+static void ti_throttle(struct tty_struct *tty);
+static void ti_unthrottle(struct tty_struct *tty);
+static int ti_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg);
+static void ti_set_termios(struct tty_struct *tty, struct usb_serial_port *port,
 	struct ktermios *old_termios);
-static int ti_tiocmget(struct usb_serial_port *port, struct file *file);
-static int ti_tiocmset(struct usb_serial_port *port, struct file *file,
+static int ti_tiocmget(struct tty_struct *tty, struct file *file);
+static int ti_tiocmset(struct tty_struct *tty, struct file *file,
 	unsigned int set, unsigned int clear);
-static void ti_break(struct usb_serial_port *port, int break_state);
+static void ti_break(struct tty_struct *tty, int break_state);
 static void ti_interrupt_callback(struct urb *urb);
 static void ti_bulk_in_callback(struct urb *urb);
 static void ti_bulk_out_callback(struct urb *urb);
@@ -192,8 +195,7 @@ static int ti_command_in_sync(struct ti_device *tdev, __u8 command,
 static int ti_write_byte(struct ti_device *tdev, unsigned long addr,
 	__u8 mask, __u8 byte);
 
-static int ti_download_firmware(struct ti_device *tdev, char *fw_name);
-
+static int ti_download_firmware(struct ti_device *tdev, int type);
 
 /* circular buffer */
 static struct circ_buf *ti_buf_alloc(void);
@@ -430,11 +432,10 @@ static int ti_startup(struct usb_serial *serial)
 
 	/* if we have only 1 configuration, download firmware */
 	if (dev->descriptor.bNumConfigurations == 1) {
-
 		if (tdev->td_is_3410)
-			status = ti_download_firmware(tdev, "ti_3410.fw");
+			status = ti_download_firmware(tdev, 3410);
 		else
-			status = ti_download_firmware(tdev, "ti_5052.fw");
+			status = ti_download_firmware(tdev, 5052);
 		if (status)
 			goto free_tdev;
 
@@ -519,7 +520,8 @@ static void ti_shutdown(struct usb_serial *serial)
 }
 
 
-static int ti_open(struct usb_serial_port *port, struct file *file)
+static int ti_open(struct tty_struct *tty,
+			struct usb_serial_port *port, struct file *file)
 {
 	struct ti_port *tport = usb_get_serial_port_data(port);
 	struct ti_device *tdev;
@@ -543,9 +545,9 @@ static int ti_open(struct usb_serial_port *port, struct file *file)
 	if (mutex_lock_interruptible(&tdev->td_open_close_lock))
 		return -ERESTARTSYS;
 
-	if (port->tty)
-		port->tty->low_latency = 
-			(tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+	if (tty)
+		tty->low_latency =
+				(tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
 	port_number = port->number - port->serial->minor;
 
@@ -573,7 +575,8 @@ static int ti_open(struct usb_serial_port *port, struct file *file)
 		}
 	}
 
-	ti_set_termios(port, port->tty->termios);
+	if (tty)
+		ti_set_termios(tty, port, tty->termios);
 
 	dbg("%s - sending TI_OPEN_PORT", __func__);
 	status = ti_command_out_sync(tdev, TI_OPEN_PORT,
@@ -610,7 +613,8 @@ static int ti_open(struct usb_serial_port *port, struct file *file)
 	usb_clear_halt(dev, port->write_urb->pipe);
 	usb_clear_halt(dev, port->read_urb->pipe);
 
-	ti_set_termios(port, port->tty->termios);
+	if (tty)
+		ti_set_termios(tty, port, tty->termios);
 
 	dbg("%s - sending TI_OPEN_PORT (2)", __func__);
 	status = ti_command_out_sync(tdev, TI_OPEN_PORT,
@@ -661,7 +665,8 @@ release_lock:
 }
 
 
-static void ti_close(struct usb_serial_port *port, struct file *file)
+static void ti_close(struct tty_struct *tty, struct usb_serial_port *port,
+							struct file *file)
 {
 	struct ti_device *tdev;
 	struct ti_port *tport;
@@ -707,8 +712,8 @@ static void ti_close(struct usb_serial_port *port, struct file *file)
 }
 
 
-static int ti_write(struct usb_serial_port *port, const unsigned char *data,
-	int count)
+static int ti_write(struct tty_struct *tty, struct usb_serial_port *port,
+			const unsigned char *data, int count)
 {
 	struct ti_port *tport = usb_get_serial_port_data(port);
 	unsigned long flags;
@@ -733,8 +738,9 @@ static int ti_write(struct usb_serial_port *port, const unsigned char *data,
 }
 
 
-static int ti_write_room(struct usb_serial_port *port)
+static int ti_write_room(struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct ti_port *tport = usb_get_serial_port_data(port);
 	int room = 0;
 	unsigned long flags;
@@ -753,8 +759,9 @@ static int ti_write_room(struct usb_serial_port *port)
 }
 
 
-static int ti_chars_in_buffer(struct usb_serial_port *port)
+static int ti_chars_in_buffer(struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct ti_port *tport = usb_get_serial_port_data(port);
 	int chars = 0;
 	unsigned long flags;
@@ -773,32 +780,26 @@ static int ti_chars_in_buffer(struct usb_serial_port *port)
 }
 
 
-static void ti_throttle(struct usb_serial_port *port)
+static void ti_throttle(struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct ti_port *tport = usb_get_serial_port_data(port);
-	struct tty_struct *tty;
 
 	dbg("%s - port %d", __func__, port->number);
 
 	if (tport == NULL)
 		return;
 
-	tty = port->tty;
-	if (!tty) {
-		dbg("%s - no tty", __func__);
-		return;
-	}
-
 	if (I_IXOFF(tty) || C_CRTSCTS(tty))
 		ti_stop_read(tport, tty);
 
 }
 
 
-static void ti_unthrottle(struct usb_serial_port *port)
+static void ti_unthrottle(struct tty_struct *tty)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct ti_port *tport = usb_get_serial_port_data(port);
-	struct tty_struct *tty;
 	int status;
 
 	dbg("%s - port %d", __func__, port->number);
@@ -806,12 +807,6 @@ static void ti_unthrottle(struct usb_serial_port *port)
 	if (tport == NULL)
 		return;
 
-	tty = port->tty;
-	if (!tty) {
-		dbg("%s - no tty", __func__);
-		return;
-	}
-
 	if (I_IXOFF(tty) || C_CRTSCTS(tty)) {
 		status = ti_restart_read(tport, tty);
 		if (status)
@@ -820,9 +815,10 @@ static void ti_unthrottle(struct usb_serial_port *port)
 }
 
 
-static int ti_ioctl(struct usb_serial_port *port, struct file *file,
+static int ti_ioctl(struct tty_struct *tty, struct file *file,
 	unsigned int cmd, unsigned long arg)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct ti_port *tport = usb_get_serial_port_data(port);
 	struct async_icount cnow;
 	struct async_icount cprev;
@@ -875,11 +871,10 @@ static int ti_ioctl(struct usb_serial_port *port, struct file *file,
 }
 
 
-static void ti_set_termios(struct usb_serial_port *port,
-	struct ktermios *old_termios)
+static void ti_set_termios(struct tty_struct *tty,
+		struct usb_serial_port *port, struct ktermios *old_termios)
 {
 	struct ti_port *tport = usb_get_serial_port_data(port);
-	struct tty_struct *tty = port->tty;
 	struct ti_uart_config *config;
 	tcflag_t cflag,iflag;
 	int baud;
@@ -1008,8 +1003,9 @@ static void ti_set_termios(struct usb_serial_port *port,
 }
 
 
-static int ti_tiocmget(struct usb_serial_port *port, struct file *file)
+static int ti_tiocmget(struct tty_struct *tty, struct file *file)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct ti_port *tport = usb_get_serial_port_data(port);
 	unsigned int result;
 	unsigned int msr;
@@ -1040,9 +1036,10 @@ static int ti_tiocmget(struct usb_serial_port *port, struct file *file)
 }
 
 
-static int ti_tiocmset(struct usb_serial_port *port, struct file *file,
+static int ti_tiocmset(struct tty_struct *tty, struct file *file,
 	unsigned int set, unsigned int clear)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct ti_port *tport = usb_get_serial_port_data(port);
 	unsigned int mcr;
 	unsigned long flags;
@@ -1074,8 +1071,9 @@ static int ti_tiocmset(struct usb_serial_port *port, struct file *file,
 }
 
 
-static void ti_break(struct usb_serial_port *port, int break_state)
+static void ti_break(struct tty_struct *tty, int break_state)
 {
+	struct usb_serial_port *port = tty->driver_data;
 	struct ti_port *tport = usb_get_serial_port_data(port);
 	int status;
 
@@ -1213,14 +1211,14 @@ static void ti_bulk_in_callback(struct urb *urb)
 		return;
 	}
 
-	if (port->tty && urb->actual_length) {
+	if (port->port.tty && urb->actual_length) {
 		usb_serial_debug_data(debug, dev, __func__,
 			urb->actual_length, urb->transfer_buffer);
 
 		if (!tport->tp_is_open)
 			dbg("%s - port closed, dropping data", __func__);
 		else
-			ti_recv(&urb->dev->dev, port->tty, urb->transfer_buffer,
+			ti_recv(&urb->dev->dev, port->port.tty, urb->transfer_buffer,
 				urb->actual_length);
 
 		spin_lock(&tport->tp_lock);
@@ -1302,7 +1300,7 @@ static void ti_send(struct ti_port *tport)
 {
 	int count, result;
 	struct usb_serial_port *port = tport->tp_port;
-	struct tty_struct *tty = port->tty;
+	struct tty_struct *tty = port->port.tty;	/* FIXME */
 	unsigned long flags;
 
 
@@ -1442,8 +1440,9 @@ static int ti_set_serial_info(struct ti_port *tport,
 		return -EFAULT;
 
 	tport->tp_flags = new_serial.flags & TI_SET_SERIAL_FLAGS;
-	if (port->tty)
-		port->tty->low_latency =
+	/* FIXME */
+	if (port->port.tty)
+		port->port.tty->low_latency =
 			(tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 	tport->tp_closing_wait = new_serial.closing_wait;
 
@@ -1477,7 +1476,7 @@ static void ti_handle_new_msr(struct ti_port *tport, __u8 msr)
 	tport->tp_msr = msr & TI_MSR_MASK;
 
 	/* handle CTS flow control */
-	tty = tport->tp_port->tty;
+	tty = tport->tp_port->port.tty;
 	if (tty && C_CRTSCTS(tty)) {
 		if (msr & TI_MSR_CTS) {
 			tty->hw_stopped = 0;
@@ -1655,65 +1654,65 @@ static int ti_write_byte(struct ti_device *tdev, unsigned long addr,
 	return status;
 }
 
-
-static int ti_download_firmware(struct ti_device *tdev,
-				char *fw_name)
+static int ti_do_download(struct usb_device *dev, int pipe,
+						u8 *buffer, int size)
 {
-	const struct firmware *fw;
-	int status = 0;
-	int buffer_size;
 	int pos;
-	int len;
+	u8 cs = 0;
 	int done;
-	__u8 cs = 0;
-	__u8 *buffer;
-	struct usb_device *dev = tdev->td_serial->dev;
 	struct ti_firmware_header *header;
-	unsigned int pipe = usb_sndbulkpipe(dev,
-		tdev->td_serial->port[0]->bulk_out_endpointAddress);
-
-	buffer_size = TI_FIRMWARE_BUF_SIZE + sizeof(struct ti_firmware_header);
-
-	if (request_firmware(&fw, fw_name, &dev->dev)) {
-		dev_err(&dev->dev, "%s - failed to load firmware \"%s\"\n",
-			__func__, fw_name);
-		return -ENOENT;
-	}
-	if (fw->size > buffer_size) {
-		dev_err(&dev->dev, "%s - firmware \"%s\" is too large\n",
-			__func__, fw_name);
-		release_firmware(fw);
-		return -EINVAL;
-	}
-
-	buffer = kmalloc(buffer_size, GFP_KERNEL);
-	if (!buffer) {
-		dev_err(&dev->dev, "%s - out of memory\n", __func__);
-		release_firmware(fw);
-		return -ENOMEM;
-	}
-
-	memcpy(buffer, fw->data, fw->size);
-	memset(buffer+fw->size, 0xff, buffer_size-fw->size);
-
-	for(pos = sizeof(struct ti_firmware_header); pos < buffer_size; pos++)
+	int status;
+	int len;
+	
+	for(pos = sizeof(struct ti_firmware_header); pos < size; pos++)
 		cs = (__u8)(cs + buffer[pos]);
 
 	header = (struct ti_firmware_header *)buffer;
-	header->wLength = cpu_to_le16((__u16)(buffer_size - sizeof(struct ti_firmware_header)));
+	header->wLength = cpu_to_le16((__u16)(size 
+					- sizeof(struct ti_firmware_header)));
 	header->bCheckSum = cs;
 
 	dbg("%s - downloading firmware", __func__);
-	for (pos = 0; pos < buffer_size; pos += done) {
-		len = min(buffer_size - pos, TI_DOWNLOAD_MAX_PACKET_SIZE);
-		status = usb_bulk_msg(dev, pipe, buffer+pos, len, &done, 1000);
+	for (pos = 0; pos < size; pos += done) {
+		len = min(size - pos, TI_DOWNLOAD_MAX_PACKET_SIZE);
+		status = usb_bulk_msg(dev, pipe, buffer + pos, len,
+								&done, 1000);
 		if (status)
 			break;
 	}
+	return status;
+}
 
-	kfree(buffer);
-	release_firmware(fw);
+static int ti_download_firmware(struct ti_device *tdev, int type)
+{
+	int status = -ENOMEM;
+	int buffer_size;
+	__u8 *buffer;
+	struct usb_device *dev = tdev->td_serial->dev;
+	unsigned int pipe = usb_sndbulkpipe(dev,
+		tdev->td_serial->port[0]->bulk_out_endpointAddress);
+	const struct firmware *fw_p;
+	char buf[32];
+	sprintf(buf, "ti_usb-%d.bin", type);
 
+	if (request_firmware(&fw_p, buf, &dev->dev)) {
+		dev_err(&dev->dev, "%s - firmware not found\n", __func__);
+		return -ENOENT;
+	}
+	if (fw_p->size > TI_FIRMWARE_BUF_SIZE) {
+		dev_err(&dev->dev, "%s - firmware too large\n", __func__);
+		return -ENOENT;
+	}
+
+	buffer_size = TI_FIRMWARE_BUF_SIZE + sizeof(struct ti_firmware_header);
+	buffer = kmalloc(buffer_size, GFP_KERNEL);
+	if (buffer) {
+		memcpy(buffer, fw_p->data, fw_p->size);
+		memset(buffer + fw_p->size, 0xff, buffer_size - fw_p->size);
+		ti_do_download(dev, pipe, buffer, fw_p->size);
+		kfree(buffer);
+	}
+	release_firmware(fw_p);
 	if (status) {
 		dev_err(&dev->dev, "%s - error downloading firmware, %d\n", __func__, status);
 		return status;