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. Move Copyright and File description at top of the file
2. Add ACPI wrapper code within CONFIG_ACPI macro
3. this change is tested with DT and ACPI boot on LS1046A platform
4. add return code if serial8250_register_8250_port fails
drivers/tty/serial/8250/8250_fsl.c | 108 +++++++++++++++++++++++++++--
1 file changed, 101 insertions(+), 7 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_fsl.c b/drivers/tty/serial/8250/8250_fsl.c
index 0d0c80905c58..c3582d8938d6 100644
--- a/drivers/tty/serial/8250/8250_fsl.c
+++ b/drivers/tty/serial/8250/8250_fsl.c
@@ -1,15 +1,12 @@
// SPDX-License-Identifier: GPL-2.0
-#include <linux/serial_reg.h>
-#include <linux/serial_8250.h>
-
-#include "8250.h"
-
/*
* 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.
+ * handler to deal with an errata and provide ACPI wrapper.
+ * 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
@@ -20,6 +17,16 @@
* IRQ event to the next one.
*/
+#include <linux/acpi.h>
+#include <linux/serial_reg.h>
+#include <linux/serial_8250.h>
+
+#include "8250.h"
+
+struct fsl8250_data {
+ int line;
+};
+
int fsl8250_handle_irq(struct uart_port *port)
{
unsigned char lsr, orig_lsr;
@@ -79,3 +86,90 @@ int fsl8250_handle_irq(struct uart_port *port)
return 1;
}
EXPORT_SYMBOL_GPL(fsl8250_handle_irq);
+
+#ifdef CONFIG_ACPI
+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)
+ return 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);
+
+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
--
2.17.1
