omap-serial: Add minimal device tree support

Adapt the driver to device tree and pass minimal platform
data from device tree needed for console boot.
No power management features will be suppported for now
since it requires more tweaks around OCP settings
to toggle forceidle/noidle/smartidle bits and handling
remote wakeup and dynamic muxing.

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Reviewed-by: Rob Herring <rob.herring@calxeda.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

1 files changed, 42 insertions, 3 deletions

diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index c5b545f19a16..ca24ab37d11c 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -38,6 +38,7 @@
 #include <linux/serial_core.h>
 #include <linux/irq.h>
 #include <linux/pm_runtime.h>
+#include <linux/of.h>
 
 #include <plat/dma.h>
 #include <plat/dmtimer.h>
@@ -1325,6 +1326,19 @@ static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
         return;
 }
 
+static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
+{
+        struct omap_uart_port_info *omap_up_info;
+
+        omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
+        if (!omap_up_info)
+                return NULL; /* out of memory */
+
+        of_property_read_u32(dev->of_node, "clock-frequency",
+                                         &omap_up_info->uartclk);
+        return omap_up_info;
+}
+
 static int serial_omap_probe(struct platform_device *pdev)
 {
         struct uart_omap_port   *up;
@@ -1332,6 +1346,9 @@ static int serial_omap_probe(struct platform_device *pdev)
         struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
         int ret = -ENOSPC;
 
+        if (pdev->dev.of_node)
+                omap_up_info = of_get_uart_port_info(&pdev->dev);
+
         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (!mem) {
                 dev_err(&pdev->dev, "no mem resource?\n");
@@ -1376,9 +1393,20 @@ static int serial_omap_probe(struct platform_device *pdev)
         up->port.regshift = 2;
         up->port.fifosize = 64;
         up->port.ops = &serial_omap_pops;
-        up->port.line = pdev->id;
-        sprintf(up->name, "OMAP UART%d", up->port.line);
 
+        if (pdev->dev.of_node)
+                up->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
+        else
+                up->port.line = pdev->id;
+
+        if (up->port.line < 0) {
+                dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
+                                                                up->port.line);
+                ret = -ENODEV;
+                goto err;
+        }
+
+        sprintf(up->name, "OMAP UART%d", up->port.line);
         up->port.mapbase = mem->start;
         up->port.membase = ioremap(mem->start, resource_size(mem));
         if (!up->port.membase) {
@@ -1531,7 +1559,7 @@ static int serial_omap_runtime_suspend(struct device *dev)
         if (!up)
                 return -EINVAL;
 
-        if (!pdata->enable_wakeup)
+        if (!pdata || !pdata->enable_wakeup)
                 return 0;
 
         if (pdata->get_context_loss_count)
@@ -1592,12 +1620,23 @@ static const struct dev_pm_ops serial_omap_dev_pm_ops = {
                                 serial_omap_runtime_resume, NULL)
 };
 
+#if defined(CONFIG_OF)
+static const struct of_device_id omap_serial_of_match[] = {
+        { .compatible = "ti,omap2-uart" },
+        { .compatible = "ti,omap3-uart" },
+        { .compatible = "ti,omap4-uart" },
+        {},
+};
+MODULE_DEVICE_TABLE(of, omap_serial_of_match);
+#endif
+
 static struct platform_driver serial_omap_driver = {
         .probe          = serial_omap_probe,
         .remove         = serial_omap_remove,
         .driver         = {
                 .name   = DRIVER_NAME,
                 .pm     = &serial_omap_dev_pm_ops,
+                .of_match_table = of_match_ptr(omap_serial_of_match),
         },
 };