1 files changed, 70 insertions, 36 deletions

diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c
index 3e0b3fac6a0e..6f7eadc424a3 100644
--- a/drivers/tty/serial/arc_uart.c
+++ b/drivers/tty/serial/arc_uart.c
@@ -37,6 +37,8 @@
 #include <linux/tty_flip.h>
 #include <linux/serial_core.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
 
 /*************************************
  * ARC UART Hardware Specs
@@ -209,12 +211,8 @@ static void arc_serial_start_tx(struct uart_port *port)
 
 static void arc_serial_rx_chars(struct arc_uart_port *uart)
 {
-        struct tty_struct *tty = tty_port_tty_get(&uart->port.state->port);
         unsigned int status, ch, flg = 0;
 
-        if (!tty)
-                return;
-
         /*
          * UART has 4 deep RX-FIFO. Driver's recongnition of this fact
          * is very subtle. Here's how ...
@@ -250,10 +248,8 @@ static void arc_serial_rx_chars(struct arc_uart_port *uart)
                 uart_insert_char(&uart->port, status, RXOERR, ch, flg);
 
 done:
-                tty_flip_buffer_push(tty);
+                tty_flip_buffer_push(&uart->port.state->port);
         }
-
-        tty_kref_put(tty);
 }
 
 /*
@@ -526,18 +522,37 @@ static struct uart_ops arc_serial_pops = {
 };
 
 static int
-arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
+arc_uart_init_one(struct platform_device *pdev, int dev_id)
 {
         struct resource *res, *res2;
         unsigned long *plat_data;
-
-        if (pdev->id < 0 || pdev->id >= CONFIG_SERIAL_ARC_NR_PORTS) {
-                dev_err(&pdev->dev, "Wrong uart platform device id.\n");
-                return -ENOENT;
-        }
+        struct arc_uart_port *uart = &arc_uart_ports[dev_id];
 
         plat_data = ((unsigned long *)(pdev->dev.platform_data));
-        uart->baud = plat_data[0];
+        if (!plat_data)
+                return -ENODEV;
+
+        uart->is_emulated = !!plat_data[0];     /* workaround ISS bug */
+
+        if (is_early_platform_device(pdev)) {
+                uart->port.uartclk = plat_data[1];
+                uart->baud = plat_data[2];
+        } else {
+                struct device_node *np = pdev->dev.of_node;
+                u32 val;
+
+                if (of_property_read_u32(np, "clock-frequency", &val)) {
+                        dev_err(&pdev->dev, "clock-frequency property NOTset\n");
+                        return -EINVAL;
+                }
+                uart->port.uartclk = val;
+
+                if (of_property_read_u32(np, "baud", &val)) {
+                        dev_err(&pdev->dev, "baud property NOT set\n");
+                        return -EINVAL;
+                }
+                uart->baud = val;
+        }
 
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (!res)
@@ -557,10 +572,9 @@ arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
         uart->port.dev = &pdev->dev;
         uart->port.iotype = UPIO_MEM;
         uart->port.flags = UPF_BOOT_AUTOCONF;
-        uart->port.line = pdev->id;
+        uart->port.line = dev_id;
         uart->port.ops = &arc_serial_pops;
 
-        uart->port.uartclk = plat_data[1];
         uart->port.fifosize = ARC_UART_TX_FIFO_SIZE;
 
         /*
@@ -569,9 +583,6 @@ arc_uart_init_one(struct platform_device *pdev, struct arc_uart_port *uart)
          */
         uart->port.ignore_status_mask = 0;
 
-        /* Real Hardware vs. emulated to work around a bug */
-        uart->is_emulated = !!plat_data[2];
-
         return 0;
 }
 
@@ -648,45 +659,52 @@ static __init void early_serial_write(struct console *con, const char *s,
         }
 }
 
-static struct __initdata console arc_early_serial_console = {
+static struct console arc_early_serial_console __initdata = {
         .name = "early_ARCuart",
         .write = early_serial_write,
         .flags = CON_PRINTBUFFER | CON_BOOT,
         .index = -1
 };
 
-static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
+static int __init arc_serial_probe_earlyprintk(struct platform_device *pdev)
 {
-        arc_early_serial_console.index = pdev->id;
+        int dev_id = pdev->id < 0 ? 0 : pdev->id;
+        int rc;
+
+        arc_early_serial_console.index = dev_id;
 
-        arc_uart_init_one(pdev, &arc_uart_ports[pdev->id]);
+        rc = arc_uart_init_one(pdev, dev_id);
+        if (rc)
+                panic("early console init failed\n");
 
         arc_serial_console_setup(&arc_early_serial_console, NULL);
 
         register_console(&arc_early_serial_console);
         return 0;
 }
-#else
-static int arc_serial_probe_earlyprintk(struct platform_device *pdev)
-{
-        return -ENODEV;
-}
 #endif  /* CONFIG_SERIAL_ARC_CONSOLE */
 
 static int arc_serial_probe(struct platform_device *pdev)
 {
-        struct arc_uart_port *uart;
-        int rc;
+        int rc, dev_id;
+        struct device_node *np = pdev->dev.of_node;
+
+        /* no device tree device */
+        if (!np)
+                return -ENODEV;
 
-        if (is_early_platform_device(pdev))
-                return arc_serial_probe_earlyprintk(pdev);
+        dev_id = of_alias_get_id(np, "serial");
+        if (dev_id < 0) {
+                dev_err(&pdev->dev, "failed to get alias id: %d\n", dev_id);
+                return dev_id;
+        }
 
-        uart = &arc_uart_ports[pdev->id];
-        rc = arc_uart_init_one(pdev, uart);
+        rc = arc_uart_init_one(pdev, dev_id);
         if (rc)
                 return rc;
 
-        return uart_add_one_port(&arc_uart_driver, &uart->port);
+        rc = uart_add_one_port(&arc_uart_driver, &arc_uart_ports[dev_id].port);
+        return rc;
 }
 
 static int arc_serial_remove(struct platform_device *pdev)
@@ -695,16 +713,32 @@ static int arc_serial_remove(struct platform_device *pdev)
         return 0;
 }
 
+static const struct of_device_id arc_uart_dt_ids[] = {
+        { .compatible = "snps,arc-uart" },
+        { /* Sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, arc_uart_dt_ids);
+
 static struct platform_driver arc_platform_driver = {
         .probe = arc_serial_probe,
         .remove = arc_serial_remove,
         .driver = {
                 .name = DRIVER_NAME,
                 .owner = THIS_MODULE,
+                .of_match_table  = arc_uart_dt_ids,
          },
 };
 
 #ifdef CONFIG_SERIAL_ARC_CONSOLE
+
+static struct platform_driver early_arc_platform_driver __initdata = {
+        .probe = arc_serial_probe_earlyprintk,
+        .remove = arc_serial_remove,
+        .driver = {
+                .name = DRIVER_NAME,
+                .owner = THIS_MODULE,
+         },
+};
 /*
  * Register an early platform driver of "earlyprintk" class.
  * ARCH platform code installs the driver and probes the early devices
@@ -712,7 +746,7 @@ static struct platform_driver arc_platform_driver = {
  * or it could be done independently, for all "earlyprintk" class drivers.
  * [see arch/arc/plat-arcfpga/platform.c]
  */
-early_platform_init("earlyprintk", &arc_platform_driver);
+early_platform_init("earlyprintk", &early_arc_platform_driver);
 
 #endif  /* CONFIG_SERIAL_ARC_CONSOLE */