diff mbox series

serial: 8250_pnp: Support configurable clock frequency

Message ID 20210705121238.1223921-1-chenhuacai@loongson.cn
State New
Headers show
Series serial: 8250_pnp: Support configurable clock frequency | expand

Commit Message

Huacai Chen July 5, 2021, 12:12 p.m. UTC 
From: Jianmin Lv <lvjianmin@loongson.cn>

ACPI-based Loongson boards need configurable rather than fixed clock
frequency for serial ports.

Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
 drivers/tty/serial/8250/8250_pnp.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/tty/serial/8250/8250_pnp.c b/drivers/tty/serial/8250/8250_pnp.c
index de90d681b64c..5f8fc724ba46 100644
--- a/drivers/tty/serial/8250/8250_pnp.c
+++ b/drivers/tty/serial/8250/8250_pnp.c
@@ -15,6 +15,7 @@ 
 #include <linux/kernel.h>
 #include <linux/serial_core.h>
 #include <linux/bitops.h>
+#include <linux/property.h>
 
 #include <asm/byteorder.h>
 
@@ -474,7 +475,9 @@  serial_pnp_probe(struct pnp_dev *dev, const struct pnp_device_id *dev_id)
 	uart.port.flags |= UPF_SKIP_TEST | UPF_BOOT_AUTOCONF;
 	if (pnp_irq_flags(dev, 0) & IORESOURCE_IRQ_SHAREABLE)
 		uart.port.flags |= UPF_SHARE_IRQ;
-	uart.port.uartclk = 1843200;
+	if (device_property_read_u32(&dev->dev, "clock-frequency", &uart.port.uartclk)) {
+		uart.port.uartclk = 1843200;
+	}
 	uart.port.dev = &dev->dev;
 
 	line = serial8250_register_8250_port(&uart);