On Mon, 2013-12-02 at 10:48 +0200, Heikki Krogerus wrote:

On Sun, Dec 01, 2013 at 10:26:18AM +0400, Sergei Ianovich wrote:

quoted

The patch adds support for 3 additional LP-8x4x built-in serial
ports.

The device can also host up to 8 extension cards with 4 serial ports
on each card for a total of 35 ports. However, I don't have
the hardware to test extension cards, so they are not supported, yet.

quoted

--- a/arch/arm/mach-pxa/include/mach/lp8x4x.h
+++ b/arch/arm/mach-pxa/include/mach/lp8x4x.h

@@ -50,6 +50,12 @@
 #define LP8X4X_CLRFALLINT	LP8X4X_P2V(0x1700901a)
 #define LP8X4X_RWRTC		LP8X4X_P2V(0x1700901c)
 #define LP8X4X_SRAMBANK		0x1700901e
+#define LP8X4X_TTYS0_QUIRK	0x17009030
+#define LP8X4X_TTYS1_QUIRK	0x17009032
+#define LP8X4X_TTYS2_QUIRK	0x17009034
+#define LP8X4X_TTYS0_IOMEM	0x17009050
+#define LP8X4X_TTYS1_IOMEM	0x17009060
+#define LP8X4X_TTYS2_IOMEM	0x17009070
+
+static void lp8x4x_set_termios(struct uart_port *port,
+		struct ktermios *termios, struct ktermios *old)
+{

<snip>

quoted

+static int request_and_remap(int i)
+{
+	if (!request_mem_region(extra_mem[i], 1, "serial"))
+		return -EBUSY;
+
+	lp8x4x_data[i].private_data = ioremap(extra_mem[i], 1);
+	if (lp8x4x_data[i].private_data)
+		return 0;
+
+	release_mem_region(extra_mem[i], 1);
+	return -ENODEV;

Instead of registering a platform device for serial8250 here, you need
to simply register a platform driver for something like lp8x4x_serial.
The platform code will to registers the platform devices for it. You
will use serial8250_register_8250_port() in your probe to register a
new port. Use 8250_em.c and 8250_dw.c under drivers/tty/serial/8250/
as an example.

You don't need to introduce plat_serial8250_port so you won't need
the QUIRK_PORT stuff. You deliver the iomem and the irq as normal
resources that the driver uses when you create the platform device.
That of course also means the driver does not need to care about the
instances. The platform code will generate a platform device for as
many ports you have and set to resources accordingly.

8250_core.c doesn't use platform infrastructure to request and map IO
memory. There will be a conflict (and an error in
serial8250_request_std_resource()), if main IO memory is requested by
the platform device, won't it?