diff options
Diffstat (limited to 'drivers/tty/serial/8250/8250_ioc3.c')
-rw-r--r-- | drivers/tty/serial/8250/8250_ioc3.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/tty/serial/8250/8250_ioc3.c b/drivers/tty/serial/8250/8250_ioc3.c new file mode 100644 index 0000000000..d5a39e105a --- /dev/null +++ b/drivers/tty/serial/8250/8250_ioc3.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * SGI IOC3 8250 UART driver + * + * Copyright (C) 2019 Thomas Bogendoerfer <tbogendoerfer@suse.de> + * + * based on code Copyright (C) 2005 Stanislaw Skowronek <skylark@unaligned.org> + * Copyright (C) 2014 Joshua Kinard <kumba@gentoo.org> + */ + +#include <linux/module.h> +#include <linux/errno.h> +#include <linux/io.h> +#include <linux/platform_device.h> + +#include "8250.h" + +#define IOC3_UARTCLK (22000000 / 3) + +struct ioc3_8250_data { + int line; +}; + +static unsigned int ioc3_serial_in(struct uart_port *p, int offset) +{ + return readb(p->membase + (offset ^ 3)); +} + +static void ioc3_serial_out(struct uart_port *p, int offset, int value) +{ + writeb(value, p->membase + (offset ^ 3)); +} + +static int serial8250_ioc3_probe(struct platform_device *pdev) +{ + struct ioc3_8250_data *data; + struct uart_8250_port up; + struct resource *r; + void __iomem *membase; + int irq, line; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!r) + return -ENODEV; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + membase = devm_ioremap(&pdev->dev, r->start, resource_size(r)); + if (!membase) + return -ENOMEM; + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + irq = 0; /* no interrupt -> use polling */ + + /* Register serial ports with 8250.c */ + memset(&up, 0, sizeof(struct uart_8250_port)); + up.port.iotype = UPIO_MEM; + up.port.uartclk = IOC3_UARTCLK; + up.port.type = PORT_16550A; + up.port.irq = irq; + up.port.flags = (UPF_BOOT_AUTOCONF | UPF_SHARE_IRQ); + up.port.dev = &pdev->dev; + up.port.membase = membase; + up.port.mapbase = r->start; + up.port.serial_in = ioc3_serial_in; + up.port.serial_out = ioc3_serial_out; + line = serial8250_register_8250_port(&up); + if (line < 0) + return line; + + platform_set_drvdata(pdev, data); + return 0; +} + +static int serial8250_ioc3_remove(struct platform_device *pdev) +{ + struct ioc3_8250_data *data = platform_get_drvdata(pdev); + + serial8250_unregister_port(data->line); + return 0; +} + +static struct platform_driver serial8250_ioc3_driver = { + .probe = serial8250_ioc3_probe, + .remove = serial8250_ioc3_remove, + .driver = { + .name = "ioc3-serial8250", + } +}; + +module_platform_driver(serial8250_ioc3_driver); + +MODULE_AUTHOR("Thomas Bogendoerfer <tbogendoerfer@suse.de>"); +MODULE_DESCRIPTION("SGI IOC3 8250 UART driver"); +MODULE_LICENSE("GPL"); |