/*
* 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/tty.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
+#include <linux/init.h>
#include <asm/io.h>
+#if defined(CONFIG_OF)
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+
+/* Match table for of_platform binding */
+static struct of_device_id ulite_of_match[] __devinitdata = {
+ { .compatible = "xlnx,opb-uartlite-1.00.b", },
+ { .compatible = "xlnx,xps-uartlite-1.00.a", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, ulite_of_match);
+
+#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)
{
- struct tty_struct *tty = port->info->tty;
+ struct tty_struct *tty = port->state->port.tty;
unsigned char ch = 0;
char flag = TTY_NORMAL;
static int ulite_transmit(struct uart_port *port, int stat)
{
- struct circ_buf *xmit = &port->info->xmit;
+ struct circ_buf *xmit = &port->state->xmit;
if (stat & ULITE_STATUS_TXFULL)
return 0;
static irqreturn_t ulite_isr(int irq, void *dev_id)
{
- struct uart_port *port = (struct uart_port *)dev_id;
- int busy;
+ struct uart_port *port = dev_id;
+ int busy, n = 0;
do {
int stat = readb(port->membase + ULITE_STATUS);
busy = ulite_receive(port, stat);
busy |= ulite_transmit(port, stat);
+ n++;
} while (busy);
- tty_flip_buffer_push(port->info->tty);
-
- return IRQ_HANDLED;
+ /* work done? */
+ if (n > 1) {
+ tty_flip_buffer_push(port->state->port.tty);
+ return IRQ_HANDLED;
+ } else {
+ return IRQ_NONE;
+ }
}
static unsigned int ulite_tx_empty(struct uart_port *port)
int ret;
ret = request_irq(port->irq, ulite_isr,
- IRQF_DISABLED | IRQF_SAMPLE_RANDOM, "uartlite", port);
+ IRQF_SHARED | IRQF_SAMPLE_RANDOM, "uartlite", port);
if (ret)
return ret;
static int ulite_request_port(struct uart_port *port)
{
+ pr_debug("ulite console: port=%p; port->mapbase=%llx\n",
+ port, (unsigned long long) port->mapbase);
+
if (!request_mem_region(port->mapbase, ULITE_REGION, "uartlite")) {
dev_err(port->dev, "Memory region busy\n");
return -EBUSY;
.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();
}
}
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;
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)
+ /* Has the device been initialized yet? */
+ 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);
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,
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,
#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;
+ port = &ulite_ports[id];
- res2 = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
- if (!res2)
- return -ENODEV;
+ 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 = NULL;
- 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 = NULL;
+ 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);
}
+/* work with hotplug and coldplug */
+MODULE_ALIAS("platform:uartlite");
+
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", __func__, 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);
+}
+
+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);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff