On Tue, Aug 25, 2020 at 07:01:35PM +0530, kuldip dwivedi wrote:
> This adds support for ACPI enumerated FSL 16550 UARTs.
> For supporting ACPI, I added a wrapper so that this driver
> can be used if firmware has exposed the HID "NXP0018" in
> DSDT table.
>
> This will be built as object file if config "SERIAL_8250_FSL"
> is enabled which depends on config "SERIAL_8250_CONSOLE".
>
> Signed-off-by: kuldip dwivedi <kuldip.dwivedi@xxxxxxxxxxxxxxxx>
> ---
>
> Notes:
> 1. revert the license change from v1
> 2. revert the file header format change from v1
> 3. remove extra headers from v1
> 4. this is tested on layerscape platform LS1046A
> with the firmware having ACPI support.
>
> This will be built as object file if config " SERIAL_8250_FSL"
> is enabled which depends on config " SERIAL_8250_CONSOLE ".
> this driver will be probed if firmware has exposed HID " NXP0018" in DSDT table
>
> drivers/tty/serial/8250/8250_fsl.c | 98 ++++++++++++++++++++++++++++++
> 1 file changed, 98 insertions(+)
>
> diff --git a/drivers/tty/serial/8250/8250_fsl.c b/drivers/tty/serial/8250/8250_fsl.c
> index 0d0c80905c58..62e5e2d33f69 100644
> --- a/drivers/tty/serial/8250/8250_fsl.c
> +++ b/drivers/tty/serial/8250/8250_fsl.c
> @@ -1,11 +1,16 @@
> // SPDX-License-Identifier: GPL-2.0
> +#include <linux/acpi.h>
> #include <linux/serial_reg.h>
> #include <linux/serial_8250.h>
>
> #include "8250.h"
>
> +#define DRIVER_NAME "fsl-ns16550-uart"
Why is this needed?
> +
> /*
> * Freescale 16550 UART "driver", Copyright (C) 2011 Paul Gortmaker.
> + * Copyright 2020 NXP
> + * Copyright 2020 Puresoftware Ltd.
Copyright info goes at the top of the file, not down here.
> *
> * This isn't a full driver; it just provides an alternate IRQ
> * handler to deal with an errata. Everything else is just
> @@ -20,6 +25,10 @@
> * IRQ event to the next one.
> */
>
> +struct fsl8250_data {
> + int line;
> +};
> +
> int fsl8250_handle_irq(struct uart_port *port)
> {
> unsigned char lsr, orig_lsr;
> @@ -79,3 +88,92 @@ int fsl8250_handle_irq(struct uart_port *port)
> return 1;
> }
> EXPORT_SYMBOL_GPL(fsl8250_handle_irq);
> +
> +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) {
> + if (irq != -EPROBE_DEFER)
> + dev_err(dev, "cannot get irq\n");
> + 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)
> + ret = data->line;
> +
> + platform_set_drvdata(pdev, data);
> + return 0;
> +}
> +
> +static int fsl8250_acpi_remove(struct platform_device *pdev)
> +{
> + struct fsl8250_data *data = platform_get_drvdata(pdev);
> +
> + serial8250_unregister_port(data->line);
> + return 0;
> +}
> +
> +static const struct acpi_device_id fsl_8250_acpi_id[] = {
> + { "NXP0018", 0 },
> + { },
> +};
> +MODULE_DEVICE_TABLE(acpi, fsl_8250_acpi_id);
Will this now break the build on non-acpi systems, which the original
driver first was written for?
Don't you need some sort of dependancy on ACPI now?
thanks,
greg k-h
