| // 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"); |