From 4001130df1a74948cfa8be02b420953a84ab83e8 Mon Sep 17 00:00:00 2001 From: Tony Prisk Date: Fri, 3 Aug 2012 20:56:25 +1200 Subject: [PATCH] serial: vt8500: Add devicetree support for vt8500-serial Increase vt8500_max_ports to 6 as the WM8505 as 6 available uarts. Use devicetree port id as primary addressing for ports but allow auto-allocation if id not specified. Signed-off-by: Tony Prisk Acked-by: Alan Cox --- drivers/tty/serial/vt8500_serial.c | 58 +++++++++++++++++++++++++++--- 1 file changed, 53 insertions(+), 5 deletions(-) diff --git a/drivers/tty/serial/vt8500_serial.c b/drivers/tty/serial/vt8500_serial.c index 2be006fb3da..205d4cf4a06 100644 --- a/drivers/tty/serial/vt8500_serial.c +++ b/drivers/tty/serial/vt8500_serial.c @@ -34,6 +34,7 @@ #include #include #include +#include /* * UART Register offsets @@ -76,6 +77,8 @@ #define RX_FIFO_INTS (RXFAF | RXFF | RXOVER | PER | FER | RXTOUT) #define TX_FIFO_INTS (TXFAE | TXFE | TXUDR) +#define VT8500_MAX_PORTS 6 + struct vt8500_port { struct uart_port uart; char name[16]; @@ -83,6 +86,13 @@ struct vt8500_port { unsigned int ier; }; +/* + * we use this variable to keep track of which ports + * have been allocated as we can't use pdev->id in + * devicetree + */ +static unsigned long vt8500_ports_in_use; + static inline void vt8500_write(struct uart_port *port, unsigned int val, unsigned int off) { @@ -431,7 +441,7 @@ static int vt8500_verify_port(struct uart_port *port, return 0; } -static struct vt8500_port *vt8500_uart_ports[4]; +static struct vt8500_port *vt8500_uart_ports[VT8500_MAX_PORTS]; static struct uart_driver vt8500_uart_driver; #ifdef CONFIG_SERIAL_VT8500_CONSOLE @@ -548,7 +558,9 @@ static int __devinit vt8500_serial_probe(struct platform_device *pdev) { struct vt8500_port *vt8500_port; struct resource *mmres, *irqres; + struct device_node *np = pdev->dev.of_node; int ret; + int port; mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); irqres = platform_get_resource(pdev, IORESOURCE_IRQ, 0); @@ -559,16 +571,46 @@ static int __devinit vt8500_serial_probe(struct platform_device *pdev) if (!vt8500_port) return -ENOMEM; + if (np) + port = of_alias_get_id(np, "serial"); + if (port > VT8500_MAX_PORTS) + port = -1; + else + port = -1; + + if (port < 0) { + /* calculate the port id */ + port = find_first_zero_bit(&vt8500_ports_in_use, + sizeof(vt8500_ports_in_use)); + } + + if (port > VT8500_MAX_PORTS) + return -ENODEV; + + /* reserve the port id */ + if (test_and_set_bit(port, &vt8500_ports_in_use)) { + /* port already in use - shouldn't really happen */ + return -EBUSY; + } + vt8500_port->uart.type = PORT_VT8500; vt8500_port->uart.iotype = UPIO_MEM; vt8500_port->uart.mapbase = mmres->start; vt8500_port->uart.irq = irqres->start; vt8500_port->uart.fifosize = 16; vt8500_port->uart.ops = &vt8500_uart_pops; - vt8500_port->uart.line = pdev->id; + vt8500_port->uart.line = port; vt8500_port->uart.dev = &pdev->dev; vt8500_port->uart.flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF; - vt8500_port->uart.uartclk = 24000000; + + vt8500_port->clk = of_clk_get(pdev->dev.of_node, 0); + if (vt8500_port->clk) { + vt8500_port->uart.uartclk = clk_get_rate(vt8500_port->clk); + } else { + /* use the default of 24Mhz if not specified and warn */ + pr_warn("%s: serial clock source not specified\n", __func__); + vt8500_port->uart.uartclk = 24000000; + } snprintf(vt8500_port->name, sizeof(vt8500_port->name), "VT8500 UART%d", pdev->id); @@ -579,7 +621,7 @@ static int __devinit vt8500_serial_probe(struct platform_device *pdev) goto err; } - vt8500_uart_ports[pdev->id] = vt8500_port; + vt8500_uart_ports[port] = vt8500_port; uart_add_one_port(&vt8500_uart_driver, &vt8500_port->uart); @@ -603,12 +645,18 @@ static int __devexit vt8500_serial_remove(struct platform_device *pdev) return 0; } +static const struct of_device_id wmt_dt_ids[] = { + { .compatible = "via,vt8500-uart", }, + {} +}; + static struct platform_driver vt8500_platform_driver = { .probe = vt8500_serial_probe, .remove = __devexit_p(vt8500_serial_remove), .driver = { .name = "vt8500_serial", .owner = THIS_MODULE, + .of_match_table = of_match_ptr(wmt_dt_ids), }, }; @@ -642,4 +690,4 @@ module_exit(vt8500_serial_exit); MODULE_AUTHOR("Alexey Charkov "); MODULE_DESCRIPTION("Driver for vt8500 serial device"); -MODULE_LICENSE("GPL"); +MODULE_LICENSE("GPL v2");