The 8250_fintek driver advertises as the PNP0501 driver; however this
conflicts with the standard 16550A uart PNP0501. The conflict causes
the 8250_fintek driver to load with _every_ PNP0501, but never probe,
and causing the entire 8250 driver stack to unload if the 8250_fintek
driver is unloaded (modprobe doesn't know that 8250_pnp rather than
8250_fintek claimed the resource).
This patch merges the Fintek driver into 8250_base. On autoconfig_16550
the device is probed to verify if it is a FINTEK device or not. Only the
address ranges that belong to the ACPI device PNP0C02 are probed. If the
vendor and product matches, the port_type is changed to PORT_F81216A.
This custom probing can be disabled completely via configuration. When a
Fintek device is not probed it will behave as a standard 16550A device,
with no RS485 capabilities.
Reported-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@xxxxxxxxx>
---
This patches includes the comments from Peter for patch:
serial: 8250: Integrate Fintek into 8250_pnp
drivers/tty/serial/8250/8250.h | 6 ++
drivers/tty/serial/8250/8250_fintek.c | 190 ++++++++++++++--------------------
drivers/tty/serial/8250/8250_port.c | 14 +++
drivers/tty/serial/8250/Kconfig | 22 ++--
drivers/tty/serial/8250/Makefile | 2 +-
include/uapi/linux/serial.h | 1 +
6 files changed, 116 insertions(+), 119 deletions(-)
diff --git a/drivers/tty/serial/8250/8250.h b/drivers/tty/serial/8250/8250.h
index 047a7ba6796a..52b5700a6c59 100644
--- a/drivers/tty/serial/8250/8250.h
+++ b/drivers/tty/serial/8250/8250.h
@@ -151,6 +151,12 @@ static inline int serial8250_pnp_init(void) { return 0; }
static inline void serial8250_pnp_exit(void) { }
#endif
+#ifdef CONFIG_SERIAL_8250_FINTEK
+int fintek_8250_probe(struct uart_8250_port *uart);
+#else
+static inline int fintek_8250_probe(struct uart_8250_port *uart) { return 0; }
+#endif
+
#ifdef CONFIG_ARCH_OMAP1
static inline int is_omap1_8250(struct uart_8250_port *pt)
{
diff --git a/drivers/tty/serial/8250/8250_fintek.c b/drivers/tty/serial/8250/8250_fintek.c
index 89474399ab89..2096d87b6de9 100644
--- a/drivers/tty/serial/8250/8250_fintek.c
+++ b/drivers/tty/serial/8250/8250_fintek.c
@@ -1,9 +1,7 @@
/*
* Probe for F81216A LPC to 4 UART
*
- * Based on drivers/tty/serial/8250_pnp.c, by Russell King, et al
- *
- * Copyright (C) 2014 Ricardo Ribalda, Qtechnology A/S
+ * Copyright (C) 2014-2016 Ricardo Ribalda, Qtechnology A/S
*
*
* This program is free software; you can redistribute it and/or modify
@@ -15,6 +13,7 @@
#include <linux/pnp.h>
#include <linux/kernel.h>
#include <linux/serial_core.h>
+#include <linux/sfi_acpi.h>
#include "8250.h"
#define ADDR_PORT 0
@@ -38,30 +37,44 @@
#define RXW4C_IRA BIT(3)
#define TXW4C_IRA BIT(2)
-#define DRIVER_NAME "8250_fintek"
-
struct fintek_8250 {
u16 base_port;
u8 index;
u8 key;
- long line;
};
+struct fintek_8250_probe {
+ struct fintek_8250 pdata;
+ u16 io_address;
+};
+
+static void _fintek_8250_enter_key(u16 base_port, u8 key)
+{
+
+ outb(key, base_port + ADDR_PORT);
+ outb(key, base_port + ADDR_PORT);
+}
+
static int fintek_8250_enter_key(u16 base_port, u8 key)
{
- if (!request_muxed_region(base_port, 2, DRIVER_NAME))
+ if (!request_muxed_region(base_port, 2, "8250_fintek"))
return -EBUSY;
- outb(key, base_port + ADDR_PORT);
- outb(key, base_port + ADDR_PORT);
+ _fintek_8250_enter_key(base_port, key);
+
return 0;
}
+static void _fintek_8250_exit_key(u16 base_port)
+{
+ outb(EXIT_KEY, base_port + ADDR_PORT);
+}
+
static void fintek_8250_exit_key(u16 base_port)
{
- outb(EXIT_KEY, base_port + ADDR_PORT);
+ return _fintek_8250_exit_key(base_port);
release_region(base_port + ADDR_PORT, 2);
}
@@ -138,21 +151,40 @@ static int fintek_8250_rs485_config(struct uart_port *port,
return 0;
}
-static int fintek_8250_base_port(u16 io_address, u8 *key, u8 *index)
+static acpi_status check_fintek_resource(struct acpi_resource *res, void *data)
{
static const u16 addr[] = {0x4e, 0x2e};
static const u8 keys[] = {0x77, 0xa0, 0x87, 0x67};
+ struct fintek_8250_probe *probe_data = data;
int i, j, k;
+ if (res->type != ACPI_RESOURCE_TYPE_IO || res->length < 2)
+ return AE_OK;
+
+
for (i = 0; i < ARRAY_SIZE(addr); i++) {
+ struct resource mem =
+ DEFINE_RES_IO(res->data.io.minimum, 2);
+
+ if (addr[i] != res->data.io.minimum)
+ continue;
+
+ /*
+ * Avoid probing on ioports requested by other
+ * devices.
+ * request_muxed_region() cannot be used here
+ * because this function is called from a non
+ * sleeping context.
+ */
+ if (!request_resource(&ioport_resource, &mem))
+ continue;
+
for (j = 0; j < ARRAY_SIZE(keys); j++) {
- if (fintek_8250_enter_key(addr[i], keys[j]))
- continue;
- if (fintek_8250_check_id(addr[i])) {
- fintek_8250_exit_key(addr[i]);
+ _fintek_8250_enter_key(addr[i], keys[j]);
+
+ if (fintek_8250_check_id(addr[i]))
continue;
- }
for (k = 0; k < 4; k++) {
u16 aux;
@@ -164,119 +196,57 @@ static int fintek_8250_base_port(u16 io_address, u8 *key, u8 *index)
aux = inb(addr[i] + DATA_PORT);
outb(IO_ADDR2, addr[i] + ADDR_PORT);
aux |= inb(addr[i] + DATA_PORT) << 8;
- if (aux != io_address)
+ if (aux != probe_data->io_address)
continue;
- fintek_8250_exit_key(addr[i]);
- *key = keys[j];
- *index = k;
- return addr[i];
+ _fintek_8250_exit_key(addr[i]);
+ probe_data->pdata.key = keys[j];
+ probe_data->pdata.base_port = addr[i];
+ probe_data->pdata.index = k;
+
+ return AE_CTRL_TERMINATE;
}
- fintek_8250_exit_key(addr[i]);
+ _fintek_8250_exit_key(addr[i]);
}
}
- return -ENODEV;
+ return AE_OK;
+
}
-static int
-fintek_8250_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
+static acpi_status find_fintek_resource(acpi_handle handle, u32 lvl,
+ void *context, void **rv)
{
- struct uart_8250_port uart;
- struct fintek_8250 *pdata;
- int base_port;
- u8 key;
- u8 index;
+ struct fintek_8250_probe *probe_data = context;
- if (!pnp_port_valid(dev, 0))
- return -ENODEV;
-
- base_port = fintek_8250_base_port(pnp_port_start(dev, 0), &key, &index);
- if (base_port < 0)
- return -ENODEV;
-
- memset(&uart, 0, sizeof(uart));
-
- pdata = devm_kzalloc(&dev->dev, sizeof(*pdata), GFP_KERNEL);
- if (!pdata)
- return -ENOMEM;
- uart.port.private_data = pdata;
+ acpi_walk_resources(handle, METHOD_NAME__CRS,
+ check_fintek_resource, probe_data);
- if (!pnp_irq_valid(dev, 0))
- return -ENODEV;
- uart.port.irq = pnp_irq(dev, 0);
- uart.port.iobase = pnp_port_start(dev, 0);
- uart.port.iotype = UPIO_PORT;
- uart.port.rs485_config = fintek_8250_rs485_config;
-
- uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
- if (pnp_irq_flags(dev, 0) & IORESOURCE_IRQ_SHAREABLE)
- uart.port.flags |= UPF_SHARE_IRQ;
- uart.port.uartclk = 1843200;
- uart.port.dev = &dev->dev;
-
- pdata->key = key;
- pdata->base_port = base_port;
- pdata->index = index;
- pdata->line = serial8250_register_8250_port(&uart);
- if (pdata->line < 0)
- return -ENODEV;
+ if (probe_data->pdata.base_port)
+ return AE_CTRL_TERMINATE;
- pnp_set_drvdata(dev, pdata);
- return 0;
+ return AE_OK;
}
-static void fintek_8250_remove(struct pnp_dev *dev)
-{
- struct fintek_8250 *pdata = pnp_get_drvdata(dev);
- if (pdata)
- serial8250_unregister_port(pdata->line);
-}
-
-#ifdef CONFIG_PM
-static int fintek_8250_suspend(struct pnp_dev *dev, pm_message_t state)
+int fintek_8250_probe(struct uart_8250_port *uart)
{
- struct fintek_8250 *pdata = pnp_get_drvdata(dev);
+ struct fintek_8250 *pdata;
+ struct fintek_8250_probe probe_data;
- if (!pdata)
+ probe_data.io_address = uart->port.iobase;
+ probe_data.pdata.base_port = 0;
+ acpi_get_devices("PNP0C02", find_fintek_resource, &probe_data, NULL);
+ if (!probe_data.pdata.base_port)
return -ENODEV;
- serial8250_suspend_port(pdata->line);
- return 0;
-}
-
-static int fintek_8250_resume(struct pnp_dev *dev)
-{
- struct fintek_8250 *pdata = pnp_get_drvdata(dev);
+ pdata = devm_kzalloc(uart->port.dev, sizeof(*pdata), GFP_ATOMIC);
if (!pdata)
- return -ENODEV;
- serial8250_resume_port(pdata->line);
- return 0;
-}
-#else
-#define fintek_8250_suspend NULL
-#define fintek_8250_resume NULL
-#endif /* CONFIG_PM */
-
-static const struct pnp_device_id fintek_dev_table[] = {
- /* Qtechnology Panel PC / IO1000 */
- { "PNP0501"},
- {}
-};
+ return -ENOMEM;
-MODULE_DEVICE_TABLE(pnp, fintek_dev_table);
+ memcpy(pdata, &probe_data.pdata, sizeof(probe_data.pdata));
+ uart->port.rs485_config = fintek_8250_rs485_config;
+ uart->port.private_data = pdata;
-static struct pnp_driver fintek_8250_driver = {
- .name = DRIVER_NAME,
- .probe = fintek_8250_probe,
- .remove = fintek_8250_remove,
- .suspend = fintek_8250_suspend,
- .resume = fintek_8250_resume,
- .id_table = fintek_dev_table,
-};
-
-module_pnp_driver(fintek_8250_driver);
-MODULE_DESCRIPTION("Fintek F812164 module");
-MODULE_AUTHOR("Ricardo Ribalda <ricardo.ribalda@xxxxxxxxx>");
-MODULE_LICENSE("GPL");
+ return 0;
+}
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index e213da01a3d7..f29b52cead71 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -272,6 +272,14 @@ static const struct serial8250_config uart_config[] = {
.rxtrig_bytes = {1, 4, 8, 14},
.flags = UART_CAP_FIFO,
},
+ [PORT_F81216A] = {
+ .name = "Fintek F81216A",
+ .fifo_size = 16,
+ .tx_loadsz = 16,
+ .fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10,
+ .rxtrig_bytes = {1, 4, 8, 14},
+ .flags = UART_CAP_FIFO,
+ },
};
/* Uart divisor latch read */
@@ -1151,6 +1159,12 @@ static void autoconfig_16550a(struct uart_8250_port *up)
up->port.type = PORT_U6_16550A;
up->capabilities |= UART_CAP_AFE;
}
+
+ /*
+ * Check if the device is a Fintek F81216A
+ */
+ if (fintek_8250_probe(up) == 0)
+ up->port.type = PORT_F81216A;
}
/*
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index 64742a086ae3..0b2855e0d9b7 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -57,6 +57,20 @@ config SERIAL_8250_PNP
This builds standard PNP serial support. You may be able to
disable this feature if you only need legacy serial support.
+config SERIAL_8250_FINTEK
+ bool "Support for Fintek F81216A LPC to 4 UART RS485 API"
+ depends on SERIAL_8250 && PNPACPI
+ ---help---
+ Selecting this option will add support for the RS485 capabilities
+ of the Fintek F81216A LPC to 4 UART.
+
+ If this option is not selected the device will be configured as a
+ standard 16550A serial port.
+
+ Probing relies on an ACPI table with one or more PNP0C02 devices.
+
+ If unsure, say N.
+
config SERIAL_8250_CONSOLE
bool "Console on 8250/16550 and compatible serial port"
depends on SERIAL_8250=y
@@ -359,14 +373,6 @@ config SERIAL_8250_OMAP_TTYO_FIXUP
not booting kernel because the serial console remains silent in case
they forgot to update the command line.
-config SERIAL_8250_FINTEK
- tristate "Support for Fintek F81216A LPC to 4 UART"
- depends on SERIAL_8250 && PNP
- help
- Selecting this option will add support for the Fintek F81216A
- LPC to 4 UART. This device has some RS485 functionality not available
- through the PNP driver. If unsure, say N.
-
config SERIAL_8250_LPC18XX
tristate "NXP LPC18xx/43xx serial port support"
depends on SERIAL_8250 && OF && (ARCH_LPC18XX || COMPILE_TEST)
diff --git a/drivers/tty/serial/8250/Makefile b/drivers/tty/serial/8250/Makefile
index c9a2d6ed87e9..367d403d28d5 100644
--- a/drivers/tty/serial/8250/Makefile
+++ b/drivers/tty/serial/8250/Makefile
@@ -7,6 +7,7 @@ obj-$(CONFIG_SERIAL_8250) += 8250.o 8250_base.o
8250-$(CONFIG_SERIAL_8250_PNP) += 8250_pnp.o
8250_base-y := 8250_port.o
8250_base-$(CONFIG_SERIAL_8250_DMA) += 8250_dma.o
+8250_base-$(CONFIG_SERIAL_8250_FINTEK) += 8250_fintek.o
obj-$(CONFIG_SERIAL_8250_GSC) += 8250_gsc.o
obj-$(CONFIG_SERIAL_8250_PCI) += 8250_pci.o
obj-$(CONFIG_SERIAL_8250_HP300) += 8250_hp300.o
@@ -23,7 +24,6 @@ obj-$(CONFIG_SERIAL_8250_FSL) += 8250_fsl.o
obj-$(CONFIG_SERIAL_8250_DW) += 8250_dw.o
obj-$(CONFIG_SERIAL_8250_EM) += 8250_em.o
obj-$(CONFIG_SERIAL_8250_OMAP) += 8250_omap.o
-obj-$(CONFIG_SERIAL_8250_FINTEK) += 8250_fintek.o
obj-$(CONFIG_SERIAL_8250_LPC18XX) += 8250_lpc18xx.o
obj-$(CONFIG_SERIAL_8250_MT6577) += 8250_mtk.o
obj-$(CONFIG_SERIAL_8250_UNIPHIER) += 8250_uniphier.o
diff --git a/include/uapi/linux/serial.h b/include/uapi/linux/serial.h
index 5d59c3ebf459..cf76df415d7d 100644
--- a/include/uapi/linux/serial.h
+++ b/include/uapi/linux/serial.h
@@ -61,6 +61,7 @@ struct serial_struct {
#define PORT_16850 12
#define PORT_RSA 13 /* RSA-DV II/S card */
#define PORT_MAX 13
+#define PORT_F81216A 14
#define SERIAL_IO_PORT 0
#define SERIAL_IO_HUB6 1
--
2.8.0.rc3
--
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