[PARISC] [MUX] Make the Serial Mux driver work as module

The following updates are based off a patch from willy:
  * Removal of the mux_card list.
  * Add the mux_remove function.

Other updates:
  * Re-organize the driver structure a bit to make the
    mux_init and mux_exit functions more symmetrical.
  * Added the del_timer.
  * Unregistered the console.

At this point I can insmod, rmmod, and re-insmod the
mux without any failures.

Signed-off-by: Ryan Bradetich <rbrad@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>

diff --git a/drivers/serial/mux.c b/drivers/serial/mux.c
index f21faf1..5ff7e05 100644 (file)
--- a/drivers/serial/mux.c
+++ b/drivers/serial/mux.c
@@ -66,13 +66,6 @@ static struct uart_driver mux_driver = {
        .nr = MUX_NR,
 };
 
-struct mux_card {
-       int port_count;
-       struct parisc_device *dev;
-       struct mux_card *next;
-};
-
-static struct mux_card *mux_card_head;
 static struct timer_list mux_timer;
 
 #define UART_PUT_CHAR(p, c) __raw_writel((c), (p)->membase + IO_DATA_REG_OFFSET)
@@ -441,37 +434,6 @@ static struct uart_ops mux_pops = {
 };
 
 /**
- * get_new_mux_card - Allocate and return a new mux card.
- *
- * This function is used to allocate and return a new mux card.
- */
-static struct mux_card * __init get_new_mux_card(void)
-{
-       struct mux_card *card = mux_card_head;
-
-       if(card == NULL) {
-               mux_card_head = kzalloc(sizeof(struct mux_card), GFP_KERNEL);
-               if(!mux_card_head) {
-                       printk(KERN_ERR "MUX: Unable to allocate memory.\n");
-                       return NULL;
-               }
-               return mux_card_head;
-       }
-
-       while(card->next) {
-               card = card->next;
-       }
-
-       card->next = kzalloc(sizeof(struct mux_card), GFP_KERNEL);
-       if(!card->next) {
-               printk(KERN_ERR "MUX: Unable to allocate memory.\n");
-               return NULL;
-       }
-
-       return card->next;
-}
-
-/**
  * mux_probe - Determine if the Serial Mux should claim this device.
  * @dev: The parisc device.
  *
@@ -480,11 +442,9 @@ static struct mux_card * __init get_new_mux_card(void)
  */
 static int __init mux_probe(struct parisc_device *dev)
 {
-       int i, status, ports;
+       int i, status, port_count;
        u8 iodc_data[32];
        unsigned long bytecnt;
-       struct uart_port *port;
-       struct mux_card *card;
 
        status = pdc_iodc_read(&bytecnt, dev->hpa.start, 0, iodc_data, 32);
        if(status != PDC_OK) {
@@ -492,17 +452,12 @@ static int __init mux_probe(struct parisc_device *dev)
                return 1;
        }
 
-       ports = GET_MUX_PORTS(iodc_data);
-       printk(KERN_INFO "Serial mux driver (%d ports) Revision: 0.4\n", ports);
+       port_count = GET_MUX_PORTS(iodc_data);
+       printk(KERN_INFO "Serial mux driver (%d ports) Revision: 0.5\n", port_count);
 
-       card = get_new_mux_card();
-       if(card == NULL)
-               return 1;
-
-       card->dev = dev;
-       card->port_count = ports;
-       request_mem_region(card->dev->hpa.start + MUX_OFFSET,
-               card->port_count * MUX_LINE_OFFSET, "Mux");
+       dev_set_drvdata(&dev->dev, (void *)(long)port_count);
+       request_mem_region(dev->hpa.start + MUX_OFFSET,
+                           port_count * MUX_LINE_OFFSET, "Mux");
 
        if(!port_cnt) {
                mux_driver.cons = MUX_CONSOLE;
@@ -512,13 +467,10 @@ static int __init mux_probe(struct parisc_device *dev)
                        printk(KERN_ERR "Serial mux: Unable to register driver.\n");
                        return 1;
                }
-
-               init_timer(&mux_timer);
-               mux_timer.function = mux_poll;
        }
 
-       for(i = 0; i < ports; ++i, ++port_cnt) {
-               port = &mux_ports[port_cnt].port;
+       for(i = 0; i < port_count; ++i, ++port_cnt) {
+               struct uart_port *port = &mux_ports[port_cnt].port;
                port->iobase    = 0;
                port->mapbase   = dev->hpa.start + MUX_OFFSET +
                                                (i * MUX_LINE_OFFSET);
@@ -543,11 +495,34 @@ static int __init mux_probe(struct parisc_device *dev)
                BUG_ON(status);
        }
 
-#ifdef CONFIG_SERIAL_MUX_CONSOLE
-        register_console(&mux_console);
-#endif
-       mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
+       return 0;
+}
 
+static int __devexit mux_remove(struct parisc_device *dev)
+{
+       int i;
+       int port_count = (long)dev_get_drvdata(&dev->dev);
+
+       /* Delete the Mux timer. */
+       del_timer(&mux_timer);
+
+       /* Find Port 0 for this card in the mux_ports list. */
+       for(i = 0; i < port_cnt; ++i) {
+               if(mux_ports[i].port.mapbase == dev->hpa.start + MUX_OFFSET)
+                       break;
+       }
+       BUG_ON(i + port_count > port_cnt);
+
+       /* Release the resources associated with each port on the device. */
+       for(; i < port_count; ++i) {
+               struct uart_port *port = &mux_ports[i].port;
+
+               uart_remove_one_port(&mux_driver, port);
+               if(port->membase)
+                       iounmap(port->membase);
+       }
+
+       release_mem_region(dev->hpa.start + MUX_OFFSET, port_count * MUX_LINE_OFFSET);
        return 0;
 }
 
@@ -562,6 +537,7 @@ static struct parisc_driver serial_mux_driver = {
        .name =         "serial_mux",
        .id_table =     mux_tbl,
        .probe =        mux_probe,
+       .remove =       __devexit_p(mux_remove),
 };
 
 /**
@@ -571,7 +547,20 @@ static struct parisc_driver serial_mux_driver = {
  */
 static int __init mux_init(void)
 {
-       return register_parisc_driver(&serial_mux_driver);
+       int status = register_parisc_driver(&serial_mux_driver);
+
+       if(port_cnt > 0) {
+               /* Start the Mux timer */
+               init_timer(&mux_timer);
+               mux_timer.function = mux_poll;
+               mod_timer(&mux_timer, jiffies + MUX_POLL_DELAY);
+
+#ifdef CONFIG_SERIAL_MUX_CONSOLE
+               register_console(&mux_console);
+#endif
+       }
+
+       return status;
 }
 
 /**
@@ -581,25 +570,15 @@ static int __init mux_init(void)
  */
 static void __exit mux_exit(void)
 {
-       int i;
-       struct mux_card *next;
-       struct mux_card *card = mux_card_head;
-
-       for (i = 0; i < port_cnt; i++) {
-               uart_remove_one_port(&mux_driver, &mux_ports[i].port);
-               if (mux_ports[i].port.membase)
-                       iounmap(mux_ports[i].port.membase);
-       }
-
-       while(card != NULL) {
-               release_mem_region(card->dev->hpa.start + MUX_OFFSET,
-                                  card->port_count * MUX_LINE_OFFSET);
-
-               next = card->next;
-               kfree(card);
-               card = next;
+       /* Delete the Mux timer. */
+       if(port_cnt > 0) {
+               del_timer(&mux_timer);
+#ifdef CONFIG_SERIAL_MUX_CONSOLE
+               unregister_console(&mux_console);
+#endif
        }
 
+       unregister_parisc_driver(&serial_mux_driver);
        uart_unregister_driver(&mux_driver);
 }