serial: 8250: Fold EndRun device support into OxSemi Tornado code

The EndRun PTP/1588 dual serial port device is based on the Oxford
Semiconductor OXPCIe952 UART device with the PCI vendor:device ID set
for EndRun Technologies and uses the same sequence to determine the
number of ports available.  Despite that we have duplicate code
specific to the EndRun device.

Remove redundant code then and factor out OxSemi Tornado device
detection.
Signed-off-by: NMaciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: NAndy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/alpine.DEB.2.21.2204181516220.9383@angie.orcam.me.ukSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/8250/8250_pci.c

@@ -994,41 +994,29 @@ static void pci_ite887x_exit(struct pci_dev *dev)
 }
 
 /*
- * EndRun Technologies.
- * Determine the number of ports available on the device.
+ * Oxford Semiconductor Inc.
+ * Check if an OxSemi device is part of the Tornado range of devices.
  */
 #define PCI_VENDOR_ID_ENDRUN			0x7401
 #define PCI_DEVICE_ID_ENDRUN_1588	0xe100
 
-static int pci_endrun_init(struct pci_dev *dev)
+static bool pci_oxsemi_tornado_p(struct pci_dev *dev)
 {
-	u8 __iomem *p;
-	unsigned long deviceID;
-	unsigned int  number_uarts = 0;
+	/* OxSemi Tornado devices are all 0xCxxx */
+	if (dev->vendor == PCI_VENDOR_ID_OXSEMI &&
+	    (dev->device & 0xf000) != 0xc000)
+		return false;
 
-	/* EndRun device is all 0xexxx */
+	/* EndRun devices are all 0xExxx */
 	if (dev->vendor == PCI_VENDOR_ID_ENDRUN &&
-		(dev->device & 0xf000) != 0xe000)
-		return 0;
-
-	p = pci_iomap(dev, 0, 5);
-	if (p == NULL)
-		return -ENOMEM;
+	    (dev->device & 0xf000) != 0xe000)
+		return false;
 
-	deviceID = ioread32(p);
-	/* EndRun device */
-	if (deviceID == 0x07000200) {
-		number_uarts = ioread8(p + 4);
-		pci_dbg(dev, "%d ports detected on EndRun PCI Express device\n", number_uarts);
-	}
-	pci_iounmap(dev, p);
-	return number_uarts;
+	return true;
 }
 
 /*
- * Oxford Semiconductor Inc.
- * Check that device is part of the Tornado range of devices, then determine
- * the number of ports available on the device.
+ * Determine the number of ports available on a Tornado device.
  */
 static int pci_oxsemi_tornado_init(struct pci_dev *dev)
 {
@@ -1036,9 +1024,7 @@ static int pci_oxsemi_tornado_init(struct pci_dev *dev)
 	unsigned long deviceID;
 	unsigned int  number_uarts = 0;
 
-	/* OxSemi Tornado devices are all 0xCxxx */
-	if (dev->vendor == PCI_VENDOR_ID_OXSEMI &&
-	    (dev->device & 0xF000) != 0xC000)
+	if (!pci_oxsemi_tornado_p(dev))
 		return 0;
 
 	p = pci_iomap(dev, 0, 5);
@@ -1049,7 +1035,10 @@ static int pci_oxsemi_tornado_init(struct pci_dev *dev)
 	/* Tornado device */
 	if (deviceID == 0x07000200) {
 		number_uarts = ioread8(p + 4);
-		pci_dbg(dev, "%d ports detected on Oxford PCI Express device\n", number_uarts);
+		pci_dbg(dev, "%d ports detected on %s PCI Express device\n",
+			number_uarts,
+			dev->vendor == PCI_VENDOR_ID_ENDRUN ?
+			"EndRun" : "Oxford");
 	}
 	pci_iounmap(dev, p);
 	return number_uarts;
@@ -2244,7 +2233,7 @@ static struct pci_serial_quirk pci_serial_quirks[] = {
 		.device		= PCI_ANY_ID,
 		.subvendor	= PCI_ANY_ID,
 		.subdevice	= PCI_ANY_ID,
-		.init		= pci_endrun_init,
+		.init		= pci_oxsemi_tornado_init,
 		.setup		= pci_default_setup,
 	},
 	/*
@@ -2667,7 +2656,6 @@ enum pci_board_num_t {
 	pbn_panacom2,
 	pbn_panacom4,
 	pbn_plx_romulus,
-	pbn_endrun_2_3906250,
 	pbn_oxsemi,
 	pbn_oxsemi_1_3906250,
 	pbn_oxsemi_2_3906250,
@@ -3189,20 +3177,6 @@ static struct pciserial_board pci_boards[] = {
 		.first_offset	= 0x03,
 	},
 
-	/*
-	 * EndRun Technologies
-	* Uses the size of PCI Base region 0 to
-	* signal now many ports are available
-	* 2 port 952 Uart support
-	*/
-	[pbn_endrun_2_3906250] = {
-		.flags		= FL_BASE0,
-		.num_ports	= 2,
-		.base_baud	= 3906250,
-		.uart_offset	= 0x200,
-		.first_offset	= 0x1000,
-	},
-
 	/*
 	 * This board uses the size of PCI Base region 0 to
 	 * signal now many ports are available
@@ -4122,13 +4096,6 @@ static const struct pci_device_id serial_pci_tbl[] = {
 	{	PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_ROMULUS,
 		0x10b5, 0x106a, 0, 0,
 		pbn_plx_romulus },
-	/*
-	* EndRun Technologies. PCI express device range.
-	*    EndRun PTP/1588 has 2 Native UARTs.
-	*/
-	{	PCI_VENDOR_ID_ENDRUN, PCI_DEVICE_ID_ENDRUN_1588,
-		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
-		pbn_endrun_2_3906250 },
 	/*
 	 * Quatech cards. These actually have configurable clocks but for
 	 * now we just use the default.
@@ -4390,6 +4357,13 @@ static const struct pci_device_id serial_pci_tbl[] = {
 	{	PCI_VENDOR_ID_DIGI, PCIE_DEVICE_ID_NEO_2_OX_IBM,
 		PCI_SUBVENDOR_ID_IBM, PCI_ANY_ID, 0, 0,
 		pbn_oxsemi_2_3906250 },
+	/*
+	 * EndRun Technologies. PCI express device range.
+	 * EndRun PTP/1588 has 2 Native UARTs utilizing OxSemi 952.
+	 */
+	{	PCI_VENDOR_ID_ENDRUN, PCI_DEVICE_ID_ENDRUN_1588,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_oxsemi_2_3906250 },
 
 	/*
 	 * SBS Technologies, Inc. P-Octal and PMC-OCTPRO cards,