8250: FIX Fourth port offset of Pericom PI7C9X7954 boards

Hi,
below patch to fix Fourth port offset of Percom PI7C9X7954 boards.

I had a problem using Fourth port on a pci express serial board based on Pericom
PI7C9X7954. Reading datasheet I notice a "special" offset assign to this port
when used in I/O mode.

Offset 0x0 ->  UART 0
Offset 0x8 ->  UART 1
Offset 0x10 ->  UART 2
Offset 0x38 ->  UART 3  <<---- This don't follow a logical sequence

This patch add a different init to last port, to have right offset.

I check also Pericom 7952 and 7958 but that devices follow logical sequence,
so they are ok.

Regards,
Angelo

Signed-off-by: Angelo Butti <buttiangelo@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index b98c157..5aeabf7 100644 (file)
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1329,6 +1329,30 @@ static int pci_default_setup(struct serial_private *priv,
        return setup_port(priv, port, bar, offset, board->reg_shift);
 }
 
+static int pci_pericom_setup(struct serial_private *priv,
+                 const struct pciserial_board *board,
+                 struct uart_8250_port *port, int idx)
+{
+       unsigned int bar, offset = board->first_offset, maxnr;
+
+       bar = FL_GET_BASE(board->flags);
+       if (board->flags & FL_BASE_BARS)
+               bar += idx;
+       else
+               offset += idx * board->uart_offset;
+
+       if (idx==3)
+               offset = 0x38;
+
+       maxnr = (pci_resource_len(priv->dev, bar) - board->first_offset) >>
+               (board->reg_shift + 3);
+
+       if (board->flags & FL_REGION_SZ_CAP && idx >= maxnr)
+               return 1;
+
+       return setup_port(priv, port, bar, offset, board->reg_shift);
+}
+
 static int
 ce4100_serial_setup(struct serial_private *priv,
                  const struct pciserial_board *board,
@@ -2096,6 +2120,16 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
                .exit           = pci_plx9050_exit,
        },
        /*
+        * Pericom (Only 7954 - It have a offset jump for port 4)
+        */
+       {
+               .vendor         = PCI_VENDOR_ID_PERICOM,
+               .device         = PCI_DEVICE_ID_PERICOM_PI7C9X7954,
+               .subvendor      = PCI_ANY_ID,
+               .subdevice      = PCI_ANY_ID,
+               .setup          = pci_pericom_setup,
+       },
+       /*
         * PLX
         */
        {