On Wed, Aug 19, 2020 at 08:59:35PM +0530, kuldip dwivedi wrote:
> This adds support for ACPI enumerated FSL 16550 UARTs.
Why? We need more information here than just this, please.
>
> Signed-off-by: kuldip dwivedi <kuldip.dwivedi@xxxxxxxxxxxxxxxx>
> ---
> drivers/tty/serial/8250/8250_fsl.c | 147 +++++++++++++++++++++++++----
> 1 file changed, 131 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/tty/serial/8250/8250_fsl.c b/drivers/tty/serial/8250/8250_fsl.c
> index 0d0c80905c58..49e5987e538b 100644
> --- a/drivers/tty/serial/8250/8250_fsl.c
> +++ b/drivers/tty/serial/8250/8250_fsl.c
> @@ -1,24 +1,50 @@
> -// SPDX-License-Identifier: GPL-2.0
> +// SPDX-License-Identifier: GPL-2.0+
Why are you changing the license of this file? Are you _SURE_ you are
allowed to do that?
> +//
> +// Freescale 16550 UART "driver"
> +//
> +// Copyright (C) 2011 Paul Gortmaker.
> +// Copyright 2020 NXP
> +// Copyright 2020 Puresoftware Ltd
> +//
> +// This isn't a full driver; it just provides an alternate IRQ
> +// handler to deal with an errata. Everything else is just
> +// using the bog standard 8250 support.
> +//
> +// We follow code flow of serial8250_default_handle_irq() but add
> +// a check for a break and insert a dummy read on the Rx for the
> +// immediately following IRQ event.
> +//
> +// We re-use the already existing "bug handling" lsr_saved_flags
> +// field to carry the "what we just did" information from the one
> +// IRQ event to the next one.
/* */ is nicer for file headers, please.
> +
> +#include <linux/acpi.h>
> +#include <linux/clk.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +
> #include <linux/serial_reg.h>
> #include <linux/serial_8250.h>
>
> +
> +#include <asm/byteorder.h>
Why the extra blank lines here? And why asm/ ? what do you need from
that?
> +
> #include "8250.h"
>
> -/*
> - * Freescale 16550 UART "driver", Copyright (C) 2011 Paul Gortmaker.
> - *
> - * This isn't a full driver; it just provides an alternate IRQ
> - * handler to deal with an errata. Everything else is just
> - * using the bog standard 8250 support.
> - *
> - * We follow code flow of serial8250_default_handle_irq() but add
> - * a check for a break and insert a dummy read on the Rx for the
> - * immediately following IRQ event.
> - *
> - * We re-use the already existing "bug handling" lsr_saved_flags
> - * field to carry the "what we just did" information from the one
> - * IRQ event to the next one.
> - */
> +#define DRIVER_NAME "fsl-ns16550-uart"
> +
> +struct fsl8250_data {
> + int line;
> +};
>
> int fsl8250_handle_irq(struct uart_port *port)
> {
> @@ -79,3 +105,92 @@ 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 fsl8250_acpi_match[] = {
> + { "NXP0018", 0 },
> + { },
> +};
> +MODULE_DEVICE_TABLE(acpi, fsl8250_acpi_match);
> +
> +static struct platform_driver fsl8250_platform_driver = {
> + .driver = {
> + .name = "fsl-16550-uart",
> + .acpi_match_table = ACPI_PTR(fsl8250_acpi_match),
> + },
> + .probe = fsl8250_acpi_probe,
> + .remove = fsl8250_acpi_remove,
> +};
> +
> +module_platform_driver(fsl8250_platform_driver);
> +
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("FSL 8250 serial port driver");
> +MODULE_ALIAS("platform:" DRIVER_NAME);
> --
> 2.17.1
>
Are you _sure_ this will work properly with the build system? You are
turning an individual file into a stand-alone module, but you didn't
touch any build files.
thanks,
greg k-h
