1 files changed, 111 insertions, 17 deletions

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index b922f5d2e61e..9988c0c305c2 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -33,6 +33,8 @@
 #include <linux/sysrq.h>
 #include <linux/tty_flip.h>
 #include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/dma-mapping.h>
 #include <linux/atmel_pdc.h>
 #include <linux/atmel_serial.h>
@@ -157,11 +159,22 @@ struct atmel_uart_port {
 };
 
 static struct atmel_uart_port atmel_ports[ATMEL_MAX_UART];
+static unsigned long atmel_ports_in_use;
 
 #ifdef SUPPORT_SYSRQ
 static struct console atmel_console;
 #endif
 
+#if defined(CONFIG_OF)
+static const struct of_device_id atmel_serial_dt_ids[] = {
+        { .compatible = "atmel,at91rm9200-usart" },
+        { .compatible = "atmel,at91sam9260-usart" },
+        { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, atmel_serial_dt_ids);
+#endif
+
 static inline struct atmel_uart_port *
 to_atmel_uart_port(struct uart_port *uart)
 {
@@ -339,7 +352,8 @@ static void atmel_stop_tx(struct uart_port *port)
         /* Disable interrupts */
         UART_PUT_IDR(port, atmel_port->tx_done_mask);
 
-        if (atmel_port->rs485.flags & SER_RS485_ENABLED)
+        if ((atmel_port->rs485.flags & SER_RS485_ENABLED) &&
+            !(atmel_port->rs485.flags & SER_RS485_RX_DURING_TX))
                 atmel_start_rx(port);
 }
 
@@ -356,7 +370,8 @@ static void atmel_start_tx(struct uart_port *port)
                            really need this.*/
                         return;
 
-                if (atmel_port->rs485.flags & SER_RS485_ENABLED)
+                if ((atmel_port->rs485.flags & SER_RS485_ENABLED) &&
+                    !(atmel_port->rs485.flags & SER_RS485_RX_DURING_TX))
                         atmel_stop_rx(port);
 
                 /* re-enable PDC transmit */
@@ -680,7 +695,8 @@ static void atmel_tx_dma(struct uart_port *port)
                 /* Enable interrupts */
                 UART_PUT_IER(port, atmel_port->tx_done_mask);
         } else {
-                if (atmel_port->rs485.flags & SER_RS485_ENABLED) {
+                if ((atmel_port->rs485.flags & SER_RS485_ENABLED) &&
+                    !(atmel_port->rs485.flags & SER_RS485_RX_DURING_TX)) {
                         /* DMA done, stop TX, start RX for RS485 */
                         atmel_start_rx(port);
                 }
@@ -1407,6 +1423,48 @@ static struct uart_ops atmel_pops = {
 #endif
 };
 
+static void __devinit atmel_of_init_port(struct atmel_uart_port *atmel_port,
+                                         struct device_node *np)
+{
+        u32 rs485_delay[2];
+
+        /* DMA/PDC usage specification */
+        if (of_get_property(np, "atmel,use-dma-rx", NULL))
+                atmel_port->use_dma_rx  = 1;
+        else
+                atmel_port->use_dma_rx  = 0;
+        if (of_get_property(np, "atmel,use-dma-tx", NULL))
+                atmel_port->use_dma_tx  = 1;
+        else
+                atmel_port->use_dma_tx  = 0;
+
+        /* rs485 properties */
+        if (of_property_read_u32_array(np, "rs485-rts-delay",
+                                            rs485_delay, 2) == 0) {
+                struct serial_rs485 *rs485conf = &atmel_port->rs485;
+
+                rs485conf->delay_rts_before_send = rs485_delay[0];
+                rs485conf->delay_rts_after_send = rs485_delay[1];
+                rs485conf->flags = 0;
+
+                if (rs485conf->delay_rts_before_send == 0 &&
+                    rs485conf->delay_rts_after_send == 0) {
+                        rs485conf->flags |= SER_RS485_RTS_ON_SEND;
+                } else {
+                        if (rs485conf->delay_rts_before_send)
+                                rs485conf->flags |= SER_RS485_RTS_BEFORE_SEND;
+                        if (rs485conf->delay_rts_after_send)
+                                rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
+                }
+
+                if (of_get_property(np, "rs485-rx-during-tx", NULL))
+                        rs485conf->flags |= SER_RS485_RX_DURING_TX;
+
+                if (of_get_property(np, "linux,rs485-enabled-at-boot-time", NULL))
+                        rs485conf->flags |= SER_RS485_ENABLED;
+        }
+}
+
 /*
  * Configure the port from the platform device resource info.
  */
@@ -1414,13 +1472,20 @@ static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port,
                                       struct platform_device *pdev)
 {
         struct uart_port *port = &atmel_port->uart;
-        struct atmel_uart_data *data = pdev->dev.platform_data;
+        struct atmel_uart_data *pdata = pdev->dev.platform_data;
+
+        if (pdev->dev.of_node) {
+                atmel_of_init_port(atmel_port, pdev->dev.of_node);
+        } else {
+                atmel_port->use_dma_rx  = pdata->use_dma_rx;
+                atmel_port->use_dma_tx  = pdata->use_dma_tx;
+                atmel_port->rs485       = pdata->rs485;
+        }
 
         port->iotype            = UPIO_MEM;
         port->flags             = UPF_BOOT_AUTOCONF;
         port->ops               = &atmel_pops;
         port->fifosize          = 1;
-        port->line              = data->num;
         port->dev               = &pdev->dev;
         port->mapbase   = pdev->resource[0].start;
         port->irq       = pdev->resource[1].start;
@@ -1430,10 +1495,10 @@ static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port,
 
         memset(&atmel_port->rx_ring, 0, sizeof(atmel_port->rx_ring));
 
-        if (data->regs)
+        if (pdata && pdata->regs) {
                 /* Already mapped by setup code */
-                port->membase = data->regs;
-        else {
+                port->membase = pdata->regs;
+        } else {
                 port->flags     |= UPF_IOREMAP;
                 port->membase   = NULL;
         }
@@ -1447,9 +1512,6 @@ static void __devinit atmel_init_port(struct atmel_uart_port *atmel_port,
                 /* only enable clock when USART is in use */
         }
 
-        atmel_port->use_dma_rx = data->use_dma_rx;
-        atmel_port->use_dma_tx = data->use_dma_tx;
-        atmel_port->rs485       = data->rs485;
         /* Use TXEMPTY for interrupt when rs485 else TXRDY or ENDTX|TXBUFE */
         if (atmel_port->rs485.flags & SER_RS485_ENABLED)
                 atmel_port->tx_done_mask = ATMEL_US_TXEMPTY;
@@ -1611,10 +1673,14 @@ static int __init atmel_console_init(void)
         if (atmel_default_console_device) {
                 struct atmel_uart_data *pdata =
                         atmel_default_console_device->dev.platform_data;
+                int id = pdata->num;
+                struct atmel_uart_port *port = &atmel_ports[id];
+
+                port->backup_imr = 0;
+                port->uart.line = id;
 
-                add_preferred_console(ATMEL_DEVICENAME, pdata->num, NULL);
-                atmel_init_port(&atmel_ports[pdata->num],
-                                atmel_default_console_device);
+                add_preferred_console(ATMEL_DEVICENAME, id, NULL);
+                atmel_init_port(port, atmel_default_console_device);
                 register_console(&atmel_console);
         }
 
@@ -1711,14 +1777,39 @@ static int atmel_serial_resume(struct platform_device *pdev)
 static int __devinit atmel_serial_probe(struct platform_device *pdev)
 {
         struct atmel_uart_port *port;
+        struct device_node *np = pdev->dev.of_node;
         struct atmel_uart_data *pdata = pdev->dev.platform_data;
         void *data;
-        int ret;
+        int ret = -ENODEV;
 
         BUILD_BUG_ON(ATMEL_SERIAL_RINGSIZE & (ATMEL_SERIAL_RINGSIZE - 1));
 
-        port = &atmel_ports[pdata->num];
+        if (np)
+                ret = of_alias_get_id(np, "serial");
+        else
+                if (pdata)
+                        ret = pdata->num;
+
+        if (ret < 0)
+                /* port id not found in platform data nor device-tree aliases:
+                 * auto-enumerate it */
+                ret = find_first_zero_bit(&atmel_ports_in_use,
+                                sizeof(atmel_ports_in_use));
+
+        if (ret > ATMEL_MAX_UART) {
+                ret = -ENODEV;
+                goto err;
+        }
+
+        if (test_and_set_bit(ret, &atmel_ports_in_use)) {
+                /* port already in use */
+                ret = -EBUSY;
+                goto err;
+        }
+
+        port = &atmel_ports[ret];
         port->backup_imr = 0;
+        port->uart.line = ret;
 
         atmel_init_port(port, pdev);
 
@@ -1764,7 +1855,7 @@ err_alloc_ring:
                 clk_put(port->clk);
                 port->clk = NULL;
         }
-
+err:
         return ret;
 }
 
@@ -1784,6 +1875,8 @@ static int __devexit atmel_serial_remove(struct platform_device *pdev)
 
         /* "port" is allocated statically, so we shouldn't free it */
 
+        clear_bit(port->line, &atmel_ports_in_use);
+
         clk_put(atmel_port->clk);
 
         return ret;
@@ -1797,6 +1890,7 @@ static struct platform_driver atmel_serial_driver = {
         .driver         = {
                 .name   = "atmel_usart",
                 .owner  = THIS_MODULE,
+                .of_match_table = of_match_ptr(atmel_serial_dt_ids),
         },
 };