* [PATCH v2 2/2] Introduce 8250_men_mcb
2017-08-02 7:58 [PATCH v2 1/2] mcb: introduce mcb_get_resource() Michael Moese
@ 2017-08-02 7:58 ` Michael Moese
2017-08-11 13:13 ` Johannes Thumshirn
0 siblings, 1 reply; 3+ messages in thread
From: Michael Moese @ 2017-08-02 7:58 UTC (permalink / raw)
To: gregkh, jslaby, linux-serial, linux-kernel
Cc: michael.moese, johannes.thumshirn
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>
---
drivers/tty/serial/8250/8250_men_mcb.c | 118 +++++++++++++++++++++++++++++++++
drivers/tty/serial/8250/Kconfig | 11 +++
drivers/tty/serial/8250/Makefile | 1 +
3 files changed, 130 insertions(+)
create mode 100644 drivers/tty/serial/8250/8250_men_mcb.c
diff --git a/drivers/tty/serial/8250/8250_men_mcb.c b/drivers/tty/serial/8250/8250_men_mcb.c
new file mode 100644
index 000000000000..308977807994
--- /dev/null
+++ b/drivers/tty/serial/8250/8250_men_mcb.c
@@ -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");
diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig
index a1161ec0256f..a5c0ef1e7695 100644
--- a/drivers/tty/serial/8250/Kconfig
+++ b/drivers/tty/serial/8250/Kconfig
@@ -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
diff --git a/drivers/tty/serial/8250/Makefile b/drivers/tty/serial/8250/Makefile
index a44a99a3e623..6a18d2d768fe 100644
--- a/drivers/tty/serial/8250/Makefile
+++ b/drivers/tty/serial/8250/Makefile
@@ -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
--
2.12.3
^ permalink raw reply related [flat|nested] 3+ messages in thread