From ea28fd56fcde69af768135e428093f94c5ca6a88 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Fri, 11 Jan 2013 11:50:23 +0530 Subject: [PATCH] serial/arc-uart: switch to devicetree based probing * DT binding for arc-uart * With alll the bits in place we can now use DT probing. Note that there's a bit of kludge right now because earlyprintk portion of driver can't use the DT infrastrcuture to get resoures/plat_data. This requires some infrastructre changes to of_flat_ framework Signed-off-by: Vineet Gupta Cc: Grant Likely Cc: Arnd Bergmann Cc: Alan Cox Cc: devicetree-discuss@lists.ozlabs.org Cc: Rob Herring Cc: Rob Landley Acked-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman --- .../bindings/tty/serial/arc-uart.txt | 26 +++++++++++ drivers/tty/serial/arc_uart.c | 43 +++++++++++++++++-- 2 files changed, 66 insertions(+), 3 deletions(-) create mode 100644 Documentation/devicetree/bindings/tty/serial/arc-uart.txt diff --git a/Documentation/devicetree/bindings/tty/serial/arc-uart.txt b/Documentation/devicetree/bindings/tty/serial/arc-uart.txt new file mode 100644 index 000000000000..c3bd8f9c9997 --- /dev/null +++ b/Documentation/devicetree/bindings/tty/serial/arc-uart.txt @@ -0,0 +1,26 @@ +* Synopsys ARC UART : Non standard UART used in some of the ARC FPGA boards + +Required properties: +- compatible : "snps,arc-uart" +- reg : offset and length of the register set for the device. +- interrupts : device interrupt +- clock-frequency : the input clock frequency for the UART +- baud : baud rate for UART + +e.g. + +arcuart0: serial@c0fc1000 { + compatible = "snps,arc-uart"; + reg = <0xc0fc1000 0x100>; + interrupts = <5>; + clock-frequency = <80000000>; + baud = <115200>; + status = "okay"; +}; + +Note: Each port should have an alias correctly numbered in "aliases" node. + +e.g. +aliases { + serial0 = &arcuart0; +}; diff --git a/drivers/tty/serial/arc_uart.c b/drivers/tty/serial/arc_uart.c index 2db64105677b..b46860104312 100644 --- a/drivers/tty/serial/arc_uart.c +++ b/drivers/tty/serial/arc_uart.c @@ -37,6 +37,8 @@ #include #include #include +#include +#include /************************************* * ARC UART Hardware Specs @@ -537,8 +539,26 @@ arc_uart_init_one(struct platform_device *pdev, int dev_id) return -ENODEV; uart->is_emulated = !!plat_data[0]; /* workaround ISS bug */ - uart->port.uartclk = plat_data[1]; - uart->baud = plat_data[2]; + + 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) @@ -673,8 +693,18 @@ static int __init arc_serial_probe_earlyprintk(struct platform_device *pdev) static int arc_serial_probe(struct platform_device *pdev) { int rc, dev_id; + struct device_node *np = pdev->dev.of_node; + + /* no device tree device */ + if (!np) + return -ENODEV; + + 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; + } - dev_id = pdev->id < 0 ? 0 : pdev->id; rc = arc_uart_init_one(pdev, dev_id); if (rc) return rc; @@ -689,12 +719,19 @@ 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, }, }; -- 2.20.1