[PATCH] MEDIATEK: serial: 8250_mtk: Add ACPI support
From: Zhiyong Tao <hidden>
Date: 2026-01-05 02:41:16
Also in:
linux-mediatek, linux-serial, lkml
Subsystem:
8250/16?50 (and clone uarts) serial driver, the rest, tty layer and serial drivers · Maintainers:
Greg Kroah-Hartman, Linus Torvalds, Jiri Slaby
From: "Zhiyong.Tao" <redacted> Add ACPI support to 8250_mtk driver. This makes it possible to use UART on ARM-based desktops with EDK2 UEFI firmware. Signed-off-by: Yenchia Chen <redacted> Signed-off-by: Zhiyong.Tao <redacted> --- drivers/tty/serial/8250/8250_mtk.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-)
diff --git a/drivers/tty/serial/8250/8250_mtk.c b/drivers/tty/serial/8250/8250_mtk.c
index 5875a7b9b4b1..e6a56cf54ae0 100644
--- a/drivers/tty/serial/8250/8250_mtk.c
+++ b/drivers/tty/serial/8250/8250_mtk.c@@ -19,6 +19,7 @@ #include <linux/dma-mapping.h> #include <linux/tty.h> #include <linux/tty_flip.h> +#include <linux/units.h> #include "8250.h"
@@ -521,6 +522,7 @@ static int mtk8250_probe(struct platform_device *pdev) struct mtk8250_data *data; struct resource *regs; int irq, err; + struct fwnode_handle *fwnode = dev_fwnode(&pdev->dev); irq = platform_get_irq(pdev, 0); if (irq < 0)
@@ -543,12 +545,13 @@ static int mtk8250_probe(struct platform_device *pdev) data->clk_count = 0; - if (pdev->dev.of_node) { + if (is_of_node(fwnode)) { err = mtk8250_probe_of(pdev, &uart.port, data); if (err) return err; - } else + } else if (!fwnode) { return -ENODEV; + } spin_lock_init(&uart.port.lock); uart.port.mapbase = regs->start;
@@ -564,14 +567,18 @@ static int mtk8250_probe(struct platform_device *pdev) uart.port.startup = mtk8250_startup; uart.port.set_termios = mtk8250_set_termios; uart.port.uartclk = clk_get_rate(data->uart_clk); + if (!uart.port.uartclk) + uart.port.uartclk = 26 * HZ_PER_MHZ; #ifdef CONFIG_SERIAL_8250_DMA if (data->dma) uart.dma = data->dma; #endif - /* Disable Rate Fix function */ - writel(0x0, uart.port.membase + + if (is_of_node(fwnode)) { + /* Disable Rate Fix function */ + writel(0x0, uart.port.membase + (MTK_UART_RATE_FIX << uart.port.regshift)); + } platform_set_drvdata(pdev, data);
@@ -649,11 +656,19 @@ static const struct of_device_id mtk8250_of_match[] = { }; MODULE_DEVICE_TABLE(of, mtk8250_of_match); +static const struct acpi_device_id mtk8250_acpi_match[] = { + { "MTKI0511" }, + { "NVDA0240" }, + {} +}; +MODULE_DEVICE_TABLE(acpi, mtk8250_acpi_match); + static struct platform_driver mtk8250_platform_driver = { .driver = { .name = "mt6577-uart", .pm = &mtk8250_pm_ops, .of_match_table = mtk8250_of_match, + .acpi_match_table = mtk8250_acpi_match, }, .probe = mtk8250_probe, .remove = mtk8250_remove,
--
2.45.2