Pull-Up mode is disabled (default) in PL2303HXD.
When the Pull-Up mode is activated, its TX/DTR/RTS external resistor will start the output function.
How to enable the Pull-Up mode of PL2303HXD
1.TX/DTR/RTS external resistor is required on the circuit diagram (PCB)
2.PL2303HXD OTP needs to be programmed to have a Pull-Up mode through 6.5V (USB_VCC,5V->6.5V)
The patch driver will read whether the PL2303HXD has a Pull-Up mode,and if so,
it will be set to enable Pull-Up mode function.
Signed-off-by: Charles Yeh <charlesyeh522@xxxxxxxxx>
---
drivers/usb/serial/pl2303.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index bb3f9aa4a909..e5d00e4a495d 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -145,6 +145,16 @@ MODULE_DEVICE_TABLE(usb, id_table);
#define UART_OVERRUN_ERROR 0x40
#define UART_CTS 0x80
+#define TYPE_HX_READ_PUM_STATUS_REG 0x8484
+#define TYPE_HX_READ_PUM_ADD 0x0404
+#define TYPE_HX_READ_PUM_DATA_REG 0x8383
+#define TYPE_HX_PULLUP_MODE_DATA 0x08
+#define TYPE_HX_PULLUP_MODE_REG 0x09
+#define TYPE_HX_PUM_ADD0 0x00
+#define TYPE_HX_PUM_DATA0 0x31
+#define TYPE_HX_PUM_ADD1 0x01
+#define TYPE_HX_PUM_DATA1 0x08
+
static void pl2303_set_break(struct usb_serial_port *port, bool enable);
enum pl2303_type {
@@ -688,6 +698,20 @@ static void pl2303_set_termios(struct tty_struct *tty,
pl2303_vendor_write(serial, 0x0, 0x0);
}
+ if (spriv->type == &pl2303_type_data[TYPE_HX]) {
+ pl2303_vendor_read(serial, TYPE_HX_READ_PUM_STATUS_REG, buf);
+ pl2303_vendor_write(serial, TYPE_HX_READ_PUM_ADD,
+ TYPE_HX_PULLUP_MODE_REG);
+ pl2303_vendor_read(serial, TYPE_HX_READ_PUM_STATUS_REG, buf);
+ pl2303_vendor_read(serial, TYPE_HX_READ_PUM_DATA_REG, buf);
+ if (*buf == TYPE_HX_PULLUP_MODE_DATA) {
+ pl2303_vendor_write(serial, TYPE_HX_PUM_ADD0,
+ TYPE_HX_PUM_DATA0);
+ pl2303_vendor_write(serial, TYPE_HX_PUM_ADD1,
+ TYPE_HX_PUM_DATA1);
+ }
+ }
+
kfree(buf);
}
--
2.19.1
