serial/8250_fintek: Support keys different than default

Chip can be configured to use entry key different than 0x77. Try all the
valid keys until one gives out the right chip id.

Reported-by: Peter Hong <peter_hong@fintek.com.tw>
Reviewed-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_fintek.c b/drivers/tty/serial/8250/8250_fintek.c
index 2c3228e84a2ee2897686f513860f862da64a72f9..5b916857671b57f7e30435e1a9e2fc0335612949 100644 (file)
--- a/drivers/tty/serial/8250/8250_fintek.c
+++ b/drivers/tty/serial/8250/8250_fintek.c
@@ -19,7 +19,6 @@
 
 #define ADDR_PORT 0
 #define DATA_PORT 1
-#define ENTRY_KEY 0x77
 #define EXIT_KEY 0xAA
 #define CHIP_ID1  0x20
 #define CHIP_ID2  0x21
@@ -42,17 +41,18 @@
 struct fintek_8250 {
        u16 base_port;
        u8 index;
+       u8 key;
        long line;
 };
 
-static int fintek_8250_enter_key(u16 base_port)
+static int fintek_8250_enter_key(u16 base_port, u8 key)
 {
 
        if (!request_muxed_region(base_port, 2, DRIVER_NAME))
                return -EBUSY;
 
-       outb(ENTRY_KEY, base_port + ADDR_PORT);
-       outb(ENTRY_KEY, base_port + ADDR_PORT);
+       outb(key, base_port + ADDR_PORT);
+       outb(key, base_port + ADDR_PORT);
        return 0;
 }
 
@@ -134,7 +134,7 @@ static int fintek_8250_rs485_config(struct uart_port *port,
        if (rs485->flags & SER_RS485_RTS_ON_SEND)
                config |= RTS_INVERT;
 
-       if (fintek_8250_enter_key(pdata->base_port))
+       if (fintek_8250_enter_key(pdata->base_port, pdata->key))
                return -EBUSY;
 
        outb(LDN, pdata->base_port + ADDR_PORT);
@@ -148,20 +148,25 @@ static int fintek_8250_rs485_config(struct uart_port *port,
        return 0;
 }
 
-static int fintek_8250_base_port(void)
+static int fintek_8250_base_port(u8 *key)
 {
        static const u16 addr[] = {0x4e, 0x2e};
-       int i;
+       static const u8 keys[] = {0x77, 0xa0, 0x87, 0x67};
+       int i, j;
 
        for (i = 0; i < ARRAY_SIZE(addr); i++) {
-               int ret;
-
-               if (fintek_8250_enter_key(addr[i]))
-                       continue;
-               ret = fintek_8250_check_id(addr[i]);
-               fintek_8250_exit_key(addr[i]);
-               if (!ret)
-                       return addr[i];
+               for (j = 0; j < ARRAY_SIZE(keys); j++) {
+                       int ret;
+
+                       if (fintek_8250_enter_key(addr[i], keys[j]))
+                               continue;
+                       ret = fintek_8250_check_id(addr[i]);
+                       fintek_8250_exit_key(addr[i]);
+                       if (!ret) {
+                               *key = keys[j];
+                               return addr[i];
+                       }
+               }
        }
 
        return -ENODEV;
@@ -174,11 +179,12 @@ fintek_8250_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
        struct fintek_8250 *pdata;
        int index;
        int base_port;
+       u8 key;
 
        if (!pnp_port_valid(dev, 0))
                return -ENODEV;
 
-       base_port = fintek_8250_base_port();
+       base_port = fintek_8250_base_port(&key);
        if (base_port < 0)
                return -ENODEV;
 
@@ -206,6 +212,7 @@ fintek_8250_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
        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);