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path: root/drivers/tty/serial/8250/8250_exar.c
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Diffstat (limited to 'drivers/tty/serial/8250/8250_exar.c')
-rw-r--r--drivers/tty/serial/8250/8250_exar.c189
1 files changed, 179 insertions, 10 deletions
diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c
index 1270ff163f63..b5c98e5bf524 100644
--- a/drivers/tty/serial/8250/8250_exar.c
+++ b/drivers/tty/serial/8250/8250_exar.c
@@ -9,10 +9,13 @@
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License.
*/
+#include <linux/acpi.h>
+#include <linux/dmi.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
+#include <linux/property.h>
#include <linux/serial_core.h>
#include <linux/serial_reg.h>
#include <linux/slab.h>
@@ -60,8 +63,50 @@
#define UART_EXAR_MPIOSEL_15_8 0x99 /* MPIOSEL[15:8] */
#define UART_EXAR_MPIOOD_15_8 0x9a /* MPIOOD[15:8] */
+#define UART_EXAR_RS485_DLY(x) ((x) << 4)
+
+/*
+ * IOT2040 MPIO wiring semantics:
+ *
+ * MPIO Port Function
+ * ---- ---- --------
+ * 0 2 Mode bit 0
+ * 1 2 Mode bit 1
+ * 2 2 Terminate bus
+ * 3 - <reserved>
+ * 4 3 Mode bit 0
+ * 5 3 Mode bit 1
+ * 6 3 Terminate bus
+ * 7 - <reserved>
+ * 8 2 Enable
+ * 9 3 Enable
+ * 10 - Red LED
+ * 11..15 - <unused>
+ */
+
+/* IOT2040 MPIOs 0..7 */
+#define IOT2040_UART_MODE_RS232 0x01
+#define IOT2040_UART_MODE_RS485 0x02
+#define IOT2040_UART_MODE_RS422 0x03
+#define IOT2040_UART_TERMINATE_BUS 0x04
+
+#define IOT2040_UART1_MASK 0x0f
+#define IOT2040_UART2_SHIFT 4
+
+#define IOT2040_UARTS_DEFAULT_MODE 0x11 /* both RS232 */
+#define IOT2040_UARTS_GPIO_LO_MODE 0x88 /* reserved pins as input */
+
+/* IOT2040 MPIOs 8..15 */
+#define IOT2040_UARTS_ENABLE 0x03
+#define IOT2040_UARTS_GPIO_HI_MODE 0xF8 /* enable & LED as outputs */
+
struct exar8250;
+struct exar8250_platform {
+ int (*rs485_config)(struct uart_port *, struct serial_rs485 *);
+ int (*register_gpio)(struct pci_dev *, struct uart_8250_port *);
+};
+
/**
* struct exar8250_board - board information
* @num_ports: number of serial ports
@@ -109,7 +154,6 @@ pci_fastcom335_setup(struct exar8250 *priv, struct pci_dev *pcidev,
u8 __iomem *p;
int err;
- port->port.flags |= UPF_EXAR_EFR;
port->port.uartclk = baud * 16;
err = default_setup(priv, pcidev, idx, offset, port);
@@ -171,24 +215,32 @@ pci_xr17c154_setup(struct exar8250 *priv, struct pci_dev *pcidev,
return default_setup(priv, pcidev, idx, offset, port);
}
-static void setup_gpio(u8 __iomem *p)
+static void setup_gpio(struct pci_dev *pcidev, u8 __iomem *p)
{
+ /*
+ * The Commtech adapters required the MPIOs to be driven low. The Exar
+ * devices will export them as GPIOs, so we pre-configure them safely
+ * as inputs.
+ */
+ u8 dir = pcidev->vendor == PCI_VENDOR_ID_EXAR ? 0xff : 0x00;
+
writeb(0x00, p + UART_EXAR_MPIOINT_7_0);
writeb(0x00, p + UART_EXAR_MPIOLVL_7_0);
writeb(0x00, p + UART_EXAR_MPIO3T_7_0);
writeb(0x00, p + UART_EXAR_MPIOINV_7_0);
- writeb(0x00, p + UART_EXAR_MPIOSEL_7_0);
+ writeb(dir, p + UART_EXAR_MPIOSEL_7_0);
writeb(0x00, p + UART_EXAR_MPIOOD_7_0);
writeb(0x00, p + UART_EXAR_MPIOINT_15_8);
writeb(0x00, p + UART_EXAR_MPIOLVL_15_8);
writeb(0x00, p + UART_EXAR_MPIO3T_15_8);
writeb(0x00, p + UART_EXAR_MPIOINV_15_8);
- writeb(0x00, p + UART_EXAR_MPIOSEL_15_8);
+ writeb(dir, p + UART_EXAR_MPIOSEL_15_8);
writeb(0x00, p + UART_EXAR_MPIOOD_15_8);
}
static void *
-xr17v35x_register_gpio(struct pci_dev *pcidev)
+__xr17v35x_register_gpio(struct pci_dev *pcidev,
+ const struct property_entry *properties)
{
struct platform_device *pdev;
@@ -196,8 +248,11 @@ xr17v35x_register_gpio(struct pci_dev *pcidev)
if (!pdev)
return NULL;
- platform_set_drvdata(pdev, pcidev);
- if (platform_device_add(pdev) < 0) {
+ pdev->dev.parent = &pcidev->dev;
+ ACPI_COMPANION_SET(&pdev->dev, ACPI_COMPANION(&pcidev->dev));
+
+ if (platform_device_add_properties(pdev, properties) < 0 ||
+ platform_device_add(pdev) < 0) {
platform_device_put(pdev);
return NULL;
}
@@ -205,17 +260,131 @@ xr17v35x_register_gpio(struct pci_dev *pcidev)
return pdev;
}
+static const struct property_entry exar_gpio_properties[] = {
+ PROPERTY_ENTRY_U32("linux,first-pin", 0),
+ PROPERTY_ENTRY_U32("ngpios", 16),
+ { }
+};
+
+static int xr17v35x_register_gpio(struct pci_dev *pcidev,
+ struct uart_8250_port *port)
+{
+ if (pcidev->vendor == PCI_VENDOR_ID_EXAR)
+ port->port.private_data =
+ __xr17v35x_register_gpio(pcidev, exar_gpio_properties);
+
+ return 0;
+}
+
+static const struct exar8250_platform exar8250_default_platform = {
+ .register_gpio = xr17v35x_register_gpio,
+};
+
+static int iot2040_rs485_config(struct uart_port *port,
+ struct serial_rs485 *rs485)
+{
+ bool is_rs485 = !!(rs485->flags & SER_RS485_ENABLED);
+ u8 __iomem *p = port->membase;
+ u8 mask = IOT2040_UART1_MASK;
+ u8 mode, value;
+
+ if (is_rs485) {
+ if (rs485->flags & SER_RS485_RX_DURING_TX)
+ mode = IOT2040_UART_MODE_RS422;
+ else
+ mode = IOT2040_UART_MODE_RS485;
+
+ if (rs485->flags & SER_RS485_TERMINATE_BUS)
+ mode |= IOT2040_UART_TERMINATE_BUS;
+ } else {
+ mode = IOT2040_UART_MODE_RS232;
+ }
+
+ if (port->line == 3) {
+ mask <<= IOT2040_UART2_SHIFT;
+ mode <<= IOT2040_UART2_SHIFT;
+ }
+
+ value = readb(p + UART_EXAR_MPIOLVL_7_0);
+ value &= ~mask;
+ value |= mode;
+ writeb(value, p + UART_EXAR_MPIOLVL_7_0);
+
+ value = readb(p + UART_EXAR_FCTR);
+ if (is_rs485)
+ value |= UART_FCTR_EXAR_485;
+ else
+ value &= ~UART_FCTR_EXAR_485;
+ writeb(value, p + UART_EXAR_FCTR);
+
+ if (is_rs485)
+ writeb(UART_EXAR_RS485_DLY(4), p + UART_MSR);
+
+ port->rs485 = *rs485;
+
+ return 0;
+}
+
+static const struct property_entry iot2040_gpio_properties[] = {
+ PROPERTY_ENTRY_U32("linux,first-pin", 10),
+ PROPERTY_ENTRY_U32("ngpios", 1),
+ { }
+};
+
+static int iot2040_register_gpio(struct pci_dev *pcidev,
+ struct uart_8250_port *port)
+{
+ u8 __iomem *p = port->port.membase;
+
+ writeb(IOT2040_UARTS_DEFAULT_MODE, p + UART_EXAR_MPIOLVL_7_0);
+ writeb(IOT2040_UARTS_GPIO_LO_MODE, p + UART_EXAR_MPIOSEL_7_0);
+ writeb(IOT2040_UARTS_ENABLE, p + UART_EXAR_MPIOLVL_15_8);
+ writeb(IOT2040_UARTS_GPIO_HI_MODE, p + UART_EXAR_MPIOSEL_15_8);
+
+ port->port.private_data =
+ __xr17v35x_register_gpio(pcidev, iot2040_gpio_properties);
+
+ return 0;
+}
+
+static const struct exar8250_platform iot2040_platform = {
+ .rs485_config = iot2040_rs485_config,
+ .register_gpio = iot2040_register_gpio,
+};
+
+static const struct dmi_system_id exar_platforms[] = {
+ {
+ .matches = {
+ DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
+ DMI_EXACT_MATCH(DMI_BOARD_ASSET_TAG,
+ "6ES7647-0AA00-1YA2"),
+ },
+ .driver_data = (void *)&iot2040_platform,
+ },
+ {}
+};
+
static int
pci_xr17v35x_setup(struct exar8250 *priv, struct pci_dev *pcidev,
struct uart_8250_port *port, int idx)
{
const struct exar8250_board *board = priv->board;
+ const struct exar8250_platform *platform;
+ const struct dmi_system_id *dmi_match;
unsigned int offset = idx * 0x400;
unsigned int baud = 7812500;
u8 __iomem *p;
int ret;
+ dmi_match = dmi_first_match(exar_platforms);
+ if (dmi_match)
+ platform = dmi_match->driver_data;
+ else
+ platform = &exar8250_default_platform;
+
port->port.uartclk = baud * 16;
+ port->port.rs485_config = platform->rs485_config;
+
/*
* Setup the uart clock for the devices on expansion slot to
* half the clock speed of the main chip (which is 125MHz)
@@ -236,12 +405,12 @@ pci_xr17v35x_setup(struct exar8250 *priv, struct pci_dev *pcidev,
if (idx == 0) {
/* Setup Multipurpose Input/Output pins. */
- setup_gpio(p);
+ setup_gpio(pcidev, p);
- port->port.private_data = xr17v35x_register_gpio(pcidev);
+ ret = platform->register_gpio(pcidev, port);
}
- return 0;
+ return ret;
}
static void pci_xr17v35x_exit(struct pci_dev *pcidev)