stdio: Pass device pointer to stdio methods

At present stdio device functions do not get any clue as to which stdio
device is being acted on. Some implementations go to great lengths to work
around this, such as defining a whole separate set of functions for each
possible device.

For driver model we need to associate a stdio_dev with a device. It doesn't
seem possible to continue with this work-around approach.

Instead, add a stdio_dev pointer to each of the stdio member functions.

Note: The serial drivers have the same problem, but it is not strictly
necessary to fix that to get driver model running. Also, if we convert
serial over to driver model the problem will go away.

Code size increases by 244 bytes for Thumb2 and 428 for PowerPC.

22: stdio: Pass device pointer to stdio methods
       arm: (for 2/2 boards)  all +244.0  bss -4.0  text +248.0
   powerpc: (for 1/1 boards)  all +428.0  text +428.0

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Marek Vasut <marex@denx.de>
Reviewed-by: Marek Vasut <marex@denx.de>

2 files changed, 52 insertions, 10 deletions

diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
index fd61a5e..803d850 100644
--- a/drivers/serial/serial.c
+++ b/drivers/serial/serial.c
@@ -254,6 +254,48 @@ void serial_initialize(void)
 	serial_assign(default_serial_console()->name);
 }
 
+int serial_stub_start(struct stdio_dev *sdev)
+{
+	struct serial_device *dev = sdev->priv;
+
+	return dev->start();
+}
+
+int serial_stub_stop(struct stdio_dev *sdev)
+{
+	struct serial_device *dev = sdev->priv;
+
+	return dev->stop();
+}
+
+void serial_stub_putc(struct stdio_dev *sdev, const char ch)
+{
+	struct serial_device *dev = sdev->priv;
+
+	dev->putc(ch);
+}
+
+void serial_stub_puts(struct stdio_dev *sdev, const char *str)
+{
+	struct serial_device *dev = sdev->priv;
+
+	dev->puts(str);
+}
+
+int serial_stub_getc(struct stdio_dev *sdev)
+{
+	struct serial_device *dev = sdev->priv;
+
+	return dev->getc();
+}
+
+int serial_stub_tstc(struct stdio_dev *sdev)
+{
+	struct serial_device *dev = sdev->priv;
+
+	return dev->tstc();
+}
+
 /**
  * serial_stdio_init() - Register serial ports with STDIO core
  *
@@ -272,12 +314,12 @@ void serial_stdio_init(void)
 		strcpy(dev.name, s->name);
 		dev.flags = DEV_FLAGS_OUTPUT | DEV_FLAGS_INPUT;
 
-		dev.start = s->start;
-		dev.stop = s->stop;
-		dev.putc = s->putc;
-		dev.puts = s->puts;
-		dev.getc = s->getc;
-		dev.tstc = s->tstc;
+		dev.start = serial_stub_start;
+		dev.stop = serial_stub_stop;
+		dev.putc = serial_stub_putc;
+		dev.puts = serial_stub_puts;
+		dev.getc = serial_stub_getc;
+		dev.tstc = serial_stub_tstc;
 
 		stdio_register(&dev);
 
diff --git a/drivers/serial/usbtty.c b/drivers/serial/usbtty.c
index 6b912ef..b030526 100644
--- a/drivers/serial/usbtty.c
+++ b/drivers/serial/usbtty.c
@@ -389,7 +389,7 @@ static void str2wide (char *str, u16 * wide)
  * Test whether a character is in the RX buffer
  */
 
-int usbtty_tstc (void)
+int usbtty_tstc(struct stdio_dev *dev)
 {
 	struct usb_endpoint_instance *endpoint =
 		&endpoint_instance[rx_endpoint];
@@ -409,7 +409,7 @@ int usbtty_tstc (void)
  * written into its argument c.
  */
 
-int usbtty_getc (void)
+int usbtty_getc(struct stdio_dev *dev)
 {
 	char c;
 	struct usb_endpoint_instance *endpoint =
@@ -429,7 +429,7 @@ int usbtty_getc (void)
 /*
  * Output a single byte to the usb client port.
  */
-void usbtty_putc (const char c)
+void usbtty_putc(struct stdio_dev *dev, const char c)
 {
 	if (!usbtty_configured ())
 		return;
@@ -484,7 +484,7 @@ static void __usbtty_puts (const char *str, int len)
 	}
 }
 
-void usbtty_puts (const char *str)
+void usbtty_puts(struct stdio_dev *dev, const char *str)
 {
 	int n;
 	int len;