linux/drivers/tty/serial/8250/8250_men_mcb.c

176 lines
4.5 KiB
C

#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/mcb.h>
#include <linux/serial.h>
#include <linux/serial_core.h>
#include <linux/serial_8250.h>
#include <uapi/linux/serial_core.h>
#define MEN_UART_ID_Z025 0x19
#define MEN_UART_ID_Z057 0x39
#define MEN_UART_ID_Z125 0x7d
#define MEN_UART_MEM_SIZE 0x10
struct serial_8250_men_mcb_data {
struct uart_8250_port uart;
int line;
};
/*
* The Z125 16550-compatible UART has no fixed base clock assigned
* So, depending on the board we're on, we need to adjust the
* parameter in order to really set the correct baudrate, and
* do so if possible without user interaction
*/
static u32 men_lookup_uartclk(struct mcb_device *mdev)
{
/* use default value if board is not available below */
u32 clkval = 1041666;
dev_info(&mdev->dev, "%s on board %s\n",
dev_name(&mdev->dev),
mdev->bus->name);
if (strncmp(mdev->bus->name, "F075", 4) == 0)
clkval = 1041666;
else if (strncmp(mdev->bus->name, "F216", 4) == 0)
clkval = 1843200;
else if (strncmp(mdev->bus->name, "G215", 4) == 0)
clkval = 1843200;
else if (strncmp(mdev->bus->name, "F210", 4) == 0)
clkval = 115200;
else
dev_info(&mdev->dev,
"board not detected, using default uartclk\n");
clkval = clkval << 4;
return clkval;
}
static unsigned int get_num_ports(struct mcb_device *mdev,
void __iomem *membase)
{
switch (mdev->id) {
case MEN_UART_ID_Z125:
return 1U;
case MEN_UART_ID_Z025:
return readb(membase) >> 4;
case MEN_UART_ID_Z057:
return 4U;
default:
dev_err(&mdev->dev, "no supported device!\n");
return -ENODEV;
}
}
static int serial_8250_men_mcb_probe(struct mcb_device *mdev,
const struct mcb_device_id *id)
{
struct serial_8250_men_mcb_data *data;
struct resource *mem;
unsigned int num_ports;
unsigned int i;
void __iomem *membase;
mem = mcb_get_resource(mdev, IORESOURCE_MEM);
if (mem == NULL)
return -ENXIO;
membase = devm_ioremap_resource(&mdev->dev, mem);
if (IS_ERR(membase))
return PTR_ERR_OR_ZERO(membase);
num_ports = get_num_ports(mdev, membase);
dev_dbg(&mdev->dev, "found a 16z%03u with %u ports\n",
mdev->id, num_ports);
if (num_ports == 0 || num_ports > 4) {
dev_err(&mdev->dev, "unexpected number of ports: %u\n",
num_ports);
return -ENODEV;
}
data = devm_kcalloc(&mdev->dev, num_ports,
sizeof(struct serial_8250_men_mcb_data),
GFP_KERNEL);
if (!data)
return -ENOMEM;
mcb_set_drvdata(mdev, data);
for (i = 0; i < num_ports; i++) {
data[i].uart.port.dev = mdev->dma_dev;
spin_lock_init(&data[i].uart.port.lock);
data[i].uart.port.type = PORT_16550;
data[i].uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ
| UPF_FIXED_TYPE;
data[i].uart.port.iotype = UPIO_MEM;
data[i].uart.port.uartclk = men_lookup_uartclk(mdev);
data[i].uart.port.regshift = 0;
data[i].uart.port.irq = mcb_get_irq(mdev);
data[i].uart.port.membase = membase;
data[i].uart.port.fifosize = 60;
data[i].uart.port.mapbase = (unsigned long) mem->start
+ i * MEN_UART_MEM_SIZE;
data[i].uart.port.iobase = data[i].uart.port.mapbase;
/* ok, register the port */
data[i].line = serial8250_register_8250_port(&data[i].uart);
if (data[i].line < 0) {
dev_err(&mdev->dev, "unable to register UART port\n");
return data[i].line;
}
dev_info(&mdev->dev, "found MCB UART: ttyS%d\n", data[i].line);
}
return 0;
}
static void serial_8250_men_mcb_remove(struct mcb_device *mdev)
{
unsigned int num_ports, i;
struct serial_8250_men_mcb_data *data = mcb_get_drvdata(mdev);
if (!data)
return;
num_ports = get_num_ports(mdev, data[0].uart.port.membase);
if (num_ports < 0 || num_ports > 4) {
dev_err(&mdev->dev, "error retrieving number of ports!\n");
return;
}
for (i = 0; i < num_ports; i++)
serial8250_unregister_port(data[i].line);
}
static const struct mcb_device_id serial_8250_men_mcb_ids[] = {
{ .device = MEN_UART_ID_Z025 },
{ .device = MEN_UART_ID_Z057 },
{ .device = MEN_UART_ID_Z125 },
{ }
};
MODULE_DEVICE_TABLE(mcb, serial_8250_men_mcb_ids);
static struct mcb_driver mcb_driver = {
.driver = {
.name = "8250_men_mcb",
.owner = THIS_MODULE,
},
.probe = serial_8250_men_mcb_probe,
.remove = serial_8250_men_mcb_remove,
.id_table = serial_8250_men_mcb_ids,
};
module_mcb_driver(mcb_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("MEN 8250 UART driver");
MODULE_AUTHOR("Michael Moese <michael.moese@men.de");
MODULE_ALIAS("mcb:16z125");
MODULE_ALIAS("mcb:16z025");
MODULE_ALIAS("mcb:16z057");