drivers/tty/serial/8250/8250_fsl.c

Source file repositories/reference/linux-study-clean/drivers/tty/serial/8250/8250_fsl.c

File Facts

System
Linux kernel
Corpus path
drivers/tty/serial/8250/8250_fsl.c
Extension
.c
Size
5368 bytes
Lines
190
Domain
Driver Families
Bucket
drivers/tty
Inferred role
Driver Families: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

struct fsl8250_data {
	int	line;
};

static int fsl8250_acpi_probe(struct platform_device *pdev)
{
	struct fsl8250_data *data;
	struct uart_8250_port port8250;
	struct device *dev = &pdev->dev;
	struct resource *regs;

	int ret, irq;

	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!regs) {
		dev_err(dev, "no registers defined\n");
		return -EINVAL;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0)
		return irq;

	memset(&port8250, 0, sizeof(port8250));

	ret = device_property_read_u32(dev, "clock-frequency",
					&port8250.port.uartclk);
	if (ret)
		return ret;

	spin_lock_init(&port8250.port.lock);

	port8250.port.mapbase           = regs->start;
	port8250.port.irq               = irq;
	port8250.port.handle_irq        = fsl8250_handle_irq;
	port8250.port.type              = PORT_16550A;
	port8250.port.flags             = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF
						| UPF_FIXED_PORT | UPF_IOREMAP
						| UPF_FIXED_TYPE;
	port8250.port.dev               = dev;
	port8250.port.mapsize           = resource_size(regs);
	port8250.port.iotype            = UPIO_MEM;
	port8250.port.irqflags          = IRQF_SHARED;

	port8250.port.membase = devm_ioremap(dev,  port8250.port.mapbase,
							port8250.port.mapsize);
	if (!port8250.port.membase)
		return -ENOMEM;

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	data->line = serial8250_register_8250_port(&port8250);
	if (data->line < 0)
		return data->line;

	platform_set_drvdata(pdev, data);
	return 0;
}

static void fsl8250_acpi_remove(struct platform_device *pdev)
{
	struct fsl8250_data *data = platform_get_drvdata(pdev);

	serial8250_unregister_port(data->line);
}

static const struct acpi_device_id fsl_8250_acpi_id[] = {
	{ "NXP0018", 0 },
	{ },
};
MODULE_DEVICE_TABLE(acpi, fsl_8250_acpi_id);

static struct platform_driver fsl8250_platform_driver = {
	.driver = {
		.name			= "fsl-16550-uart",
		.acpi_match_table	= ACPI_PTR(fsl_8250_acpi_id),
	},
	.probe			= fsl8250_acpi_probe,
	.remove			= fsl8250_acpi_remove,
};

module_platform_driver(fsl8250_platform_driver);
#endif

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Handling of Freescale specific 8250 variants");

Annotation

Implementation Notes