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path: root/drivers/tty/serial/8250/8250_pci.c
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Diffstat (limited to 'drivers/tty/serial/8250/8250_pci.c')
-rw-r--r--drivers/tty/serial/8250/8250_pci.c61
1 files changed, 59 insertions, 2 deletions
diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index 614be0f13a31..0d35c77fad9e 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -19,6 +19,7 @@
#include <linux/serial_core.h>
#include <linux/8250_pci.h>
#include <linux/bitops.h>
+#include <linux/bitfield.h>
#include <asm/byteorder.h>
#include <asm/io.h>
@@ -1970,6 +1971,20 @@ pci_sunix_setup(struct serial_private *priv,
#define MOXA_GPIO_PIN2 BIT(2)
+#define MOXA_RS232 0x00
+#define MOXA_RS422 0x01
+#define MOXA_RS485_4W 0x0B
+#define MOXA_RS485_2W 0x0F
+#define MOXA_UIR_OFFSET 0x04
+#define MOXA_EVEN_RS_MASK GENMASK(3, 0)
+#define MOXA_ODD_RS_MASK GENMASK(7, 4)
+
+enum {
+ MOXA_SUPP_RS232 = BIT(0),
+ MOXA_SUPP_RS422 = BIT(1),
+ MOXA_SUPP_RS485 = BIT(2),
+};
+
static bool pci_moxa_is_mini_pcie(unsigned short device)
{
if (device == PCI_DEVICE_ID_MOXA_CP102N ||
@@ -1983,12 +1998,54 @@ static bool pci_moxa_is_mini_pcie(unsigned short device)
return false;
}
+static unsigned int pci_moxa_supported_rs(struct pci_dev *dev)
+{
+ switch (dev->device & 0x0F00) {
+ case 0x0000:
+ case 0x0600:
+ return MOXA_SUPP_RS232;
+ case 0x0100:
+ return MOXA_SUPP_RS232 | MOXA_SUPP_RS422 | MOXA_SUPP_RS485;
+ case 0x0300:
+ return MOXA_SUPP_RS422 | MOXA_SUPP_RS485;
+ }
+ return 0;
+}
+
+static int pci_moxa_set_interface(const struct pci_dev *dev,
+ unsigned int port_idx,
+ u8 mode)
+{
+ resource_size_t iobar_addr = pci_resource_start(dev, 2);
+ resource_size_t UIR_addr = iobar_addr + MOXA_UIR_OFFSET + port_idx / 2;
+ u8 val;
+
+ val = inb(UIR_addr);
+
+ if (port_idx % 2) {
+ val &= ~MOXA_ODD_RS_MASK;
+ val |= FIELD_PREP(MOXA_ODD_RS_MASK, mode);
+ } else {
+ val &= ~MOXA_EVEN_RS_MASK;
+ val |= FIELD_PREP(MOXA_EVEN_RS_MASK, mode);
+ }
+ outb(val, UIR_addr);
+
+ return 0;
+}
+
static int pci_moxa_init(struct pci_dev *dev)
{
unsigned short device = dev->device;
resource_size_t iobar_addr = pci_resource_start(dev, 2);
- unsigned int num_ports = (device & 0x00F0) >> 4;
- u8 val;
+ unsigned int num_ports = (device & 0x00F0) >> 4, i;
+ u8 val, init_mode = MOXA_RS232;
+
+ if (!(pci_moxa_supported_rs(dev) & MOXA_SUPP_RS232)) {
+ init_mode = MOXA_RS422;
+ }
+ for (i = 0; i < num_ports; ++i)
+ pci_moxa_set_interface(dev, i, init_mode);
/*
* Enable hardware buffer to prevent break signal output when system boots up.