lkml.org 
[lkml]   [2012]   [Aug]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCHv4 3/9] serial: vt8500: Add devicetree support for vt8500-serial
Date
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 <linux@prisktech.co.nz>
---
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 2be006f..205d4cf 100644
--- a/drivers/tty/serial/vt8500_serial.c
+++ b/drivers/tty/serial/vt8500_serial.c
@@ -34,6 +34,7 @@
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
+#include <linux/of.h>

/*
* 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 <alchark@gmail.com>");
MODULE_DESCRIPTION("Driver for vt8500 serial device");
-MODULE_LICENSE("GPL");
+MODULE_LICENSE("GPL v2");
--
1.7.9.5


\
 
 \ /
  Last update: 2012-08-23 10:41    [W:0.111 / U:0.256 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site