serial: 8250_pci: Add support for 16 port Exar boards

commit 96a5d18bc1338786fecac73599f1681f59a59a8e upstream.

The Exar XR17V358 chip usually provides only 8 ports. But two chips can be
combined to act as a single 16 port chip. Therefor one chip is configured
as master the second as slave by connecting the mode pin to VCC (master)
or GND (slave).

Then the master chip is reporting a different device-id depending on
whether a slave is detected or not. The UARTs 8-15 are addressed from
0x2000-0x3fff. So the offset of 0x400 from UART to UART can be used to
address all 16 ports as before.

See: https://www.exar.com/common/content/document.ashx?id=1587 page 11

Signed-off-by: Soeren Grunewald <soeren.grunewald@desy.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index ae4a16e8ee1019f12e36ae9776b757a0c0074e45..f01eec579695bd050b9ea7a13364fb39e7d49fef 100644 (file)
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1802,6 +1802,8 @@ pci_wch_ch353_setup(struct serial_private *priv,
 #define PCI_DEVICE_ID_PERICOM_PI7C9X7954       0x7954
 #define PCI_DEVICE_ID_PERICOM_PI7C9X7958       0x7958
 
+#define PCI_DEVICE_ID_EXAR_XR17V8358   0x8358
+
 /* Unknown vendors/cards - this should not be in linux/pci_ids.h */
 #define PCI_SUBDEVICE_ID_UNKNOWN_0x1584        0x1584
 #define PCI_SUBDEVICE_ID_UNKNOWN_0x1588        0x1588
@@ -2281,6 +2283,13 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = {
                .subdevice      = PCI_ANY_ID,
                .setup          = pci_xr17v35x_setup,
        },
+       {
+               .vendor = PCI_VENDOR_ID_EXAR,
+               .device = PCI_DEVICE_ID_EXAR_XR17V8358,
+               .subvendor      = PCI_ANY_ID,
+               .subdevice      = PCI_ANY_ID,
+               .setup          = pci_xr17v35x_setup,
+       },
        /*
         * Xircom cards
         */
@@ -2729,6 +2738,7 @@ enum pci_board_num_t {
        pbn_exar_XR17V352,
        pbn_exar_XR17V354,
        pbn_exar_XR17V358,
+       pbn_exar_XR17V8358,
        pbn_exar_ibm_saturn,
        pbn_pasemi_1682M,
        pbn_ni8430_2,
@@ -3402,6 +3412,14 @@ static struct pciserial_board pci_boards[] = {
                .reg_shift      = 0,
                .first_offset   = 0,
        },
+       [pbn_exar_XR17V8358] = {
+               .flags          = FL_BASE0,
+               .num_ports      = 16,
+               .base_baud      = 7812500,
+               .uart_offset    = 0x400,
+               .reg_shift      = 0,
+               .first_offset   = 0,
+       },
        [pbn_exar_ibm_saturn] = {
                .flags          = FL_BASE0,
                .num_ports      = 1,
@@ -4797,7 +4815,7 @@ static struct pci_device_id serial_pci_tbl[] = {
                0,
                0, pbn_exar_XR17C158 },
        /*
-        * Exar Corp. XR17V35[248] Dual/Quad/Octal PCIe UARTs
+        * Exar Corp. XR17V[48]35[248] Dual/Quad/Octal/Hexa PCIe UARTs
         */
        {       PCI_VENDOR_ID_EXAR, PCI_DEVICE_ID_EXAR_XR17V352,
                PCI_ANY_ID, PCI_ANY_ID,
@@ -4811,7 +4829,10 @@ static struct pci_device_id serial_pci_tbl[] = {
                PCI_ANY_ID, PCI_ANY_ID,
                0,
                0, pbn_exar_XR17V358 },
-
+       {       PCI_VENDOR_ID_EXAR, PCI_DEVICE_ID_EXAR_XR17V8358,
+               PCI_ANY_ID, PCI_ANY_ID,
+               0,
+               0, pbn_exar_XR17V8358 },
        /*
         * Pericom PI7C9X795[1248] Uno/Dual/Quad/Octal UART
         */