Driver core: Remove unneeded get_{device,driver}() calls.
[linux-2.6.git] / drivers / serial / uartlite.c
index 92eba89..8094340 100644 (file)
@@ -1,7 +1,8 @@
 /*
  * uartlite.c: Serial driver for Xilinx uartlite serial controller
  *
- * Peter Korsgaard <jacmet@sunsite.dk>
+ * Copyright (C) 2006 Peter Korsgaard <jacmet@sunsite.dk>
+ * Copyright (C) 2007 Secret Lab Technologies Ltd.
  *
  * This file is licensed under the terms of the GNU General Public License
  * version 2.  This program is licensed "as is" without any warranty of any
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <asm/io.h>
+#if defined(CONFIG_OF)
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#endif
 
+#define ULITE_NAME             "ttyUL"
 #define ULITE_MAJOR            204
 #define ULITE_MINOR            187
 #define ULITE_NR_UARTS         4
 
-/* For register details see datasheet:
-   http://www.xilinx.com/bvdocs/ipcenter/data_sheet/opb_uartlite.pdf
-*/
+/* ---------------------------------------------------------------------
+ * Register definitions
+ *
+ * For register details see datasheet:
+ * http://www.xilinx.com/bvdocs/ipcenter/data_sheet/opb_uartlite.pdf
+ */
+
 #define ULITE_RX               0x00
 #define ULITE_TX               0x04
 #define ULITE_STATUS           0x08
 #define ULITE_CONTROL_IE       0x10
 
 
-static struct uart_port ports[ULITE_NR_UARTS];
+static struct uart_port ulite_ports[ULITE_NR_UARTS];
+
+/* ---------------------------------------------------------------------
+ * Core UART driver operations
+ */
 
 static int ulite_receive(struct uart_port *port, int stat)
 {
@@ -256,7 +270,7 @@ static void ulite_release_port(struct uart_port *port)
 {
        release_mem_region(port->mapbase, ULITE_REGION);
        iounmap(port->membase);
-       port->membase = 0;
+       port->membase = NULL;
 }
 
 static int ulite_request_port(struct uart_port *port)
@@ -278,8 +292,8 @@ static int ulite_request_port(struct uart_port *port)
 
 static void ulite_config_port(struct uart_port *port, int flags)
 {
-       ulite_request_port(port);
-       port->type = PORT_UARTLITE;
+       if (!ulite_request_port(port))
+               port->type = PORT_UARTLITE;
 }
 
 static int ulite_verify_port(struct uart_port *port, struct serial_struct *ser)
@@ -307,16 +321,22 @@ static struct uart_ops ulite_ops = {
        .verify_port    = ulite_verify_port
 };
 
+/* ---------------------------------------------------------------------
+ * Console driver operations
+ */
+
 #ifdef CONFIG_SERIAL_UARTLITE_CONSOLE
 static void ulite_console_wait_tx(struct uart_port *port)
 {
        int i;
+       u8 val;
 
-       /* wait up to 10ms for the character(s) to be sent */
-       for (i = 0; i < 10000; i++) {
-               if (readb(port->membase + ULITE_STATUS) & ULITE_STATUS_TXEMPTY)
+       /* Spin waiting for TX fifo to have space available */
+       for (i = 0; i < 100000; i++) {
+               val = readb(port->membase + ULITE_STATUS);
+               if ((val & ULITE_STATUS_TXFULL) == 0)
                        break;
-               udelay(1);
+               cpu_relax();
        }
 }
 
@@ -329,7 +349,7 @@ static void ulite_console_putchar(struct uart_port *port, int ch)
 static void ulite_console_write(struct console *co, const char *s,
                                unsigned int count)
 {
-       struct uart_port *port = &ports[co->index];
+       struct uart_port *port = &ulite_ports[co->index];
        unsigned long flags;
        unsigned int ier;
        int locked = 1;
@@ -355,6 +375,32 @@ static void ulite_console_write(struct console *co, const char *s,
                spin_unlock_irqrestore(&port->lock, flags);
 }
 
+#if defined(CONFIG_OF)
+static inline void __init ulite_console_of_find_device(int id)
+{
+       struct device_node *np;
+       struct resource res;
+       const unsigned int *of_id;
+       int rc;
+
+       for_each_compatible_node(np, NULL, "xilinx,uartlite") {
+               of_id = of_get_property(np, "port-number", NULL);
+               if ((!of_id) || (*of_id != id))
+                       continue;
+
+               rc = of_address_to_resource(np, 0, &res);
+               if (rc)
+                       continue;
+
+               ulite_ports[id].mapbase = res.start;
+               of_node_put(np);
+               return;
+       }
+}
+#else /* CONFIG_OF */
+static inline void __init ulite_console_of_find_device(int id) { /* do nothing */ }
+#endif /* CONFIG_OF */
+
 static int __init ulite_console_setup(struct console *co, char *options)
 {
        struct uart_port *port;
@@ -366,11 +412,23 @@ static int __init ulite_console_setup(struct console *co, char *options)
        if (co->index < 0 || co->index >= ULITE_NR_UARTS)
                return -EINVAL;
 
-       port = &ports[co->index];
+       port = &ulite_ports[co->index];
 
-       /* not initialized yet? */
-       if (!port->membase)
+       /* Check if it is an OF device */
+       if (!port->mapbase)
+               ulite_console_of_find_device(co->index);
+
+       /* Do we have a device now? */
+       if (!port->mapbase) {
+               pr_debug("console on ttyUL%i not present\n", co->index);
                return -ENODEV;
+       }
+
+       /* not initialized yet? */
+       if (!port->membase) {
+               if (ulite_request_port(port))
+                       return -ENODEV;
+       }
 
        if (options)
                uart_parse_options(options, &baud, &parity, &bits, &flow);
@@ -381,7 +439,7 @@ static int __init ulite_console_setup(struct console *co, char *options)
 static struct uart_driver ulite_uart_driver;
 
 static struct console ulite_console = {
-       .name   = "ttyUL",
+       .name   = ULITE_NAME,
        .write  = ulite_console_write,
        .device = uart_console_device,
        .setup  = ulite_console_setup,
@@ -403,7 +461,7 @@ console_initcall(ulite_console_init);
 static struct uart_driver ulite_uart_driver = {
        .owner          = THIS_MODULE,
        .driver_name    = "uartlite",
-       .dev_name       = "ttyUL",
+       .dev_name       = ULITE_NAME,
        .major          = ULITE_MAJOR,
        .minor          = ULITE_MINOR,
        .nr             = ULITE_NR_UARTS,
@@ -412,88 +470,225 @@ static struct uart_driver ulite_uart_driver = {
 #endif
 };
 
-static int __devinit ulite_probe(struct platform_device *pdev)
+/* ---------------------------------------------------------------------
+ * Port assignment functions (mapping devices to uart_port structures)
+ */
+
+/** ulite_assign: register a uartlite device with the driver
+ *
+ * @dev: pointer to device structure
+ * @id: requested id number.  Pass -1 for automatic port assignment
+ * @base: base address of uartlite registers
+ * @irq: irq number for uartlite
+ *
+ * Returns: 0 on success, <0 otherwise
+ */
+static int __devinit ulite_assign(struct device *dev, int id, u32 base, int irq)
 {
-       struct resource *res, *res2;
        struct uart_port *port;
+       int rc;
 
-       if (pdev->id < 0 || pdev->id >= ULITE_NR_UARTS)
+       /* if id = -1; then scan for a free id and use that */
+       if (id < 0) {
+               for (id = 0; id < ULITE_NR_UARTS; id++)
+                       if (ulite_ports[id].mapbase == 0)
+                               break;
+       }
+       if (id < 0 || id >= ULITE_NR_UARTS) {
+               dev_err(dev, "%s%i too large\n", ULITE_NAME, id);
                return -EINVAL;
+       }
 
-       if (ports[pdev->id].membase)
+       if ((ulite_ports[id].mapbase) && (ulite_ports[id].mapbase != base)) {
+               dev_err(dev, "cannot assign to %s%i; it is already in use\n",
+                       ULITE_NAME, id);
                return -EBUSY;
+       }
 
-       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-       if (!res)
-               return -ENODEV;
-
-       res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
-       if (!res2)
-               return -ENODEV;
+       port = &ulite_ports[id];
+
+       spin_lock_init(&port->lock);
+       port->fifosize = 16;
+       port->regshift = 2;
+       port->iotype = UPIO_MEM;
+       port->iobase = 1; /* mark port in use */
+       port->mapbase = base;
+       port->membase = NULL;
+       port->ops = &ulite_ops;
+       port->irq = irq;
+       port->flags = UPF_BOOT_AUTOCONF;
+       port->dev = dev;
+       port->type = PORT_UNKNOWN;
+       port->line = id;
+
+       dev_set_drvdata(dev, port);
+
+       /* Register the port */
+       rc = uart_add_one_port(&ulite_uart_driver, port);
+       if (rc) {
+               dev_err(dev, "uart_add_one_port() failed; err=%i\n", rc);
+               port->mapbase = 0;
+               dev_set_drvdata(dev, NULL);
+               return rc;
+       }
 
-       port = &ports[pdev->id];
+       return 0;
+}
 
-       port->fifosize  = 16;
-       port->regshift  = 2;
-       port->iotype    = UPIO_MEM;
-       port->iobase    = 1; /* mark port in use */
-       port->mapbase   = res->start;
-       port->membase   = 0;
-       port->ops       = &ulite_ops;
-       port->irq       = res2->start;
-       port->flags     = UPF_BOOT_AUTOCONF;
-       port->dev       = &pdev->dev;
-       port->type      = PORT_UNKNOWN;
-       port->line      = pdev->id;
+/** ulite_release: register a uartlite device with the driver
+ *
+ * @dev: pointer to device structure
+ */
+static int __devexit ulite_release(struct device *dev)
+{
+       struct uart_port *port = dev_get_drvdata(dev);
+       int rc = 0;
 
-       uart_add_one_port(&ulite_uart_driver, port);
-       platform_set_drvdata(pdev, port);
+       if (port) {
+               rc = uart_remove_one_port(&ulite_uart_driver, port);
+               dev_set_drvdata(dev, NULL);
+               port->mapbase = 0;
+       }
 
-       return 0;
+       return rc;
 }
 
-static int ulite_remove(struct platform_device *pdev)
+/* ---------------------------------------------------------------------
+ * Platform bus binding
+ */
+
+static int __devinit ulite_probe(struct platform_device *pdev)
 {
-       struct uart_port *port = platform_get_drvdata(pdev);
+       struct resource *res, *res2;
 
-       platform_set_drvdata(pdev, NULL);
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (!res)
+               return -ENODEV;
 
-       if (port)
-               uart_remove_one_port(&ulite_uart_driver, port);
+       res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+       if (!res2)
+               return -ENODEV;
 
-       /* mark port as free */
-       port->membase = 0;
+       return ulite_assign(&pdev->dev, pdev->id, res->start, res2->start);
+}
 
-       return 0;
+static int __devexit ulite_remove(struct platform_device *pdev)
+{
+       return ulite_release(&pdev->dev);
 }
 
 static struct platform_driver ulite_platform_driver = {
        .probe  = ulite_probe,
-       .remove = ulite_remove,
+       .remove = __devexit_p(ulite_remove),
        .driver = {
                   .owner = THIS_MODULE,
                   .name  = "uartlite",
                   },
 };
 
+/* ---------------------------------------------------------------------
+ * OF bus bindings
+ */
+#if defined(CONFIG_OF)
+static int __devinit
+ulite_of_probe(struct of_device *op, const struct of_device_id *match)
+{
+       struct resource res;
+       const unsigned int *id;
+       int irq, rc;
+
+       dev_dbg(&op->dev, "%s(%p, %p)\n", __FUNCTION__, op, match);
+
+       rc = of_address_to_resource(op->node, 0, &res);
+       if (rc) {
+               dev_err(&op->dev, "invalid address\n");
+               return rc;
+       }
+
+       irq = irq_of_parse_and_map(op->node, 0);
+
+       id = of_get_property(op->node, "port-number", NULL);
+
+       return ulite_assign(&op->dev, id ? *id : -1, res.start+3, irq);
+}
+
+static int __devexit ulite_of_remove(struct of_device *op)
+{
+       return ulite_release(&op->dev);
+}
+
+/* Match table for of_platform binding */
+static struct of_device_id __devinit ulite_of_match[] = {
+       { .type = "serial", .compatible = "xilinx,uartlite", },
+       {},
+};
+MODULE_DEVICE_TABLE(of, ulite_of_match);
+
+static struct of_platform_driver ulite_of_driver = {
+       .owner = THIS_MODULE,
+       .name = "uartlite",
+       .match_table = ulite_of_match,
+       .probe = ulite_of_probe,
+       .remove = __devexit_p(ulite_of_remove),
+       .driver = {
+               .name = "uartlite",
+       },
+};
+
+/* Registration helpers to keep the number of #ifdefs to a minimum */
+static inline int __init ulite_of_register(void)
+{
+       pr_debug("uartlite: calling of_register_platform_driver()\n");
+       return of_register_platform_driver(&ulite_of_driver);
+}
+
+static inline void __exit ulite_of_unregister(void)
+{
+       of_unregister_platform_driver(&ulite_of_driver);
+}
+#else /* CONFIG_OF */
+/* CONFIG_OF not enabled; do nothing helpers */
+static inline int __init ulite_of_register(void) { return 0; }
+static inline void __exit ulite_of_unregister(void) { }
+#endif /* CONFIG_OF */
+
+/* ---------------------------------------------------------------------
+ * Module setup/teardown
+ */
+
 int __init ulite_init(void)
 {
        int ret;
 
+       pr_debug("uartlite: calling uart_register_driver()\n");
        ret = uart_register_driver(&ulite_uart_driver);
        if (ret)
-               return ret;
+               goto err_uart;
 
+       ret = ulite_of_register();
+       if (ret)
+               goto err_of;
+
+       pr_debug("uartlite: calling platform_driver_register()\n");
        ret = platform_driver_register(&ulite_platform_driver);
        if (ret)
-               uart_unregister_driver(&ulite_uart_driver);
+               goto err_plat;
 
+       return 0;
+
+err_plat:
+       ulite_of_unregister();
+err_of:
+       uart_unregister_driver(&ulite_uart_driver);
+err_uart:
+       printk(KERN_ERR "registering uartlite driver failed: err=%i", ret);
        return ret;
 }
 
 void __exit ulite_exit(void)
 {
        platform_driver_unregister(&ulite_platform_driver);
+       ulite_of_unregister();
        uart_unregister_driver(&ulite_uart_driver);
 }