diff options
Diffstat (limited to 'drivers/usb/serial/pl2303.c')
| -rw-r--r-- | drivers/usb/serial/pl2303.c | 33 |
1 files changed, 29 insertions, 4 deletions
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c index f1d904706758..55122ac84518 100644 --- a/drivers/usb/serial/pl2303.c +++ b/drivers/usb/serial/pl2303.c @@ -145,6 +145,8 @@ MODULE_DEVICE_TABLE(usb, id_table); #define UART_OVERRUN_ERROR 0x40 #define UART_CTS 0x80 +#define PL2303_FLOWCTRL_MASK 0xf0 + static void pl2303_set_break(struct usb_serial_port *port, bool enable); enum pl2303_type { @@ -225,6 +227,29 @@ static int pl2303_vendor_write(struct usb_serial *serial, u16 value, u16 index) return 0; } +static int pl2303_update_reg(struct usb_serial *serial, u8 reg, u8 mask, u8 val) +{ + int ret = 0; + u8 *buf; + + buf = kmalloc(1, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + ret = pl2303_vendor_read(serial, reg | 0x80, buf); + if (ret) + goto out_free; + + *buf &= ~mask; + *buf |= val & mask; + + ret = pl2303_vendor_write(serial, reg, *buf); +out_free: + kfree(buf); + + return ret; +} + static int pl2303_probe(struct usb_serial *serial, const struct usb_device_id *id) { @@ -694,13 +719,13 @@ static void pl2303_set_termios(struct tty_struct *tty, if (C_CRTSCTS(tty)) { if (spriv->quirks & PL2303_QUIRK_LEGACY) - pl2303_vendor_write(serial, 0x0, 0x41); + pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x40); else - pl2303_vendor_write(serial, 0x0, 0x61); + pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0x60); } else if (pl2303_enable_xonxoff(tty, spriv->type)) { - pl2303_vendor_write(serial, 0x0, 0xc0); + pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0xc0); } else { - pl2303_vendor_write(serial, 0x0, 0x0); + pl2303_update_reg(serial, 0, PL2303_FLOWCTRL_MASK, 0); } kfree(buf); |