iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Introduce 8250_men_mcb

Browse Source 
This patch introduces the 8250_men_mcb driver for the MEN 16Z125
IP-Core. This is a 16550-type UART with a 60 byte FIFO.
Due to strange old hardware, every board using this IP core requires
different values for uartclk. A reasonable default is included in
addition to the support of three boards. Additional values for other
boards will be added later.

This v2 has some whitespace fixes, I screwed this up yesterday.

Signed-off-by: Michael Moese <michael.moese@men.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Michael Moese 2017-08-02 09:58:53 +02:00 committed by Greg Kroah-Hartman
parent 2ce8008711
commit 562e6ef81f
3 changed files with 130 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

118
drivers/tty/serial/8250/8250_men_mcb.c Normal file
View File

@ -0,0 +1,118 @@
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.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>
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_z125_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
dev_info(&mdev->dev,
"board not detected, using default uartclk\n");
clkval = clkval << 4;
return clkval;
}
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;
data = devm_kzalloc(&mdev->dev,
sizeof(struct serial_8250_men_mcb_data),
GFP_KERNEL);
if (!data)
return -ENOMEM;
mcb_set_drvdata(mdev, data);
data->uart.port.dev = mdev->dma_dev;
spin_lock_init(&data->uart.port.lock);
data->uart.port.type = PORT_16550;
data->uart.port.flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
data->uart.port.iotype = UPIO_MEM;
data->uart.port.uartclk = men_z125_lookup_uartclk(mdev);
data->uart.port.regshift = 0;
data->uart.port.fifosize = 60;
mem = mcb_get_resource(mdev, IORESOURCE_MEM);
if (mem == NULL)
return -ENXIO;
data->uart.port.irq = mcb_get_irq(mdev);
data->uart.port.membase = devm_ioremap_resource(&mdev->dev, mem);
if (IS_ERR(data->uart.port.membase))
return PTR_ERR_OR_ZERO(data->uart.port.membase);
data->uart.port.mapbase = (unsigned long) mem->start;
data->uart.port.iobase = data->uart.port.mapbase;
/* ok, register the port */
data->line = serial8250_register_8250_port(&data->uart);
if (data->line < 0)
return data->line;
dev_info(&mdev->dev, "found 16Z125 UART: ttyS%d\n", data->line);
return 0;
}
static void serial_8250_men_mcb_remove(struct mcb_device *mdev)
{
struct serial_8250_men_mcb_data *data = mcb_get_drvdata(mdev);
if (data)
serial8250_unregister_port(data->line);
}
static const struct mcb_device_id serial_8250_men_mcb_ids[] = {
{ .device = 0x7d },
{ }
};
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 16z125 8250 UART driver");
MODULE_AUTHOR("Michael Moese <michael.moese@men.de");
MODULE_ALIAS("mcb:16z125");

11
drivers/tty/serial/8250/Kconfig
View File

@ -155,6 +155,17 @@ config SERIAL_8250_CS
If unsure, say N.
config SERIAL_8250_MEN_MCB
tristate "MEN Z125 UART device support"
depends on MCB && SERIAL_8250
help
This enables support for FPGA based UARTs found on many MEN
boards. This driver enables support for the Z125 UARTs.
To compile this driver as a module, chose M here: the
module will be called 8250_men_mcb.
config SERIAL_8250_NR_UARTS
int "Maximum number of 8250/16550 serial ports"
depends on SERIAL_8250

1
drivers/tty/serial/8250/Makefile
View File

@ -23,6 +23,7 @@ obj-$(CONFIG_SERIAL_8250_BOCA) += 8250_boca.o
obj-$(CONFIG_SERIAL_8250_EXAR_ST16C554) += 8250_exar_st16c554.o
obj-$(CONFIG_SERIAL_8250_HUB6) += 8250_hub6.o
obj-$(CONFIG_SERIAL_8250_FSL) += 8250_fsl.o
obj-$(CONFIG_SERIAL_8250_MEN_MCB) += 8250_men_mcb.o
obj-$(CONFIG_SERIAL_8250_DW) += 8250_dw.o
obj-$(CONFIG_SERIAL_8250_EM) += 8250_em.o
obj-$(CONFIG_SERIAL_8250_OMAP) += 8250_omap.o