diff options
Diffstat (limited to 'drivers/usb/serial/pl2303.c')
| -rw-r--r-- | drivers/usb/serial/pl2303.c | 43 |
1 files changed, 32 insertions, 11 deletions
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c index e7a84f0f517..bedf8e47713 100644 --- a/drivers/usb/serial/pl2303.c +++ b/drivers/usb/serial/pl2303.c @@ -139,6 +139,7 @@ enum pl2303_type { HX_TA, /* HX(A) / X(A) / TA version */ /* TODO: improve */ HXD_EA_RA_SA, /* HXD / EA / RA / SA version */ /* TODO: improve */ TB, /* TB version */ + HX_CLONE, /* Cheap and less functional clone of the HX chip */ }; /* * NOTE: don't know the difference between type 0 and type 1, @@ -206,8 +207,23 @@ static int pl2303_startup(struct usb_serial *serial) * the device descriptors of the X/HX, HXD, EA, RA, SA, TA, TB */ if (le16_to_cpu(serial->dev->descriptor.bcdDevice) == 0x300) { - type = HX_TA; - type_str = "X/HX/TA"; + /* Check if the device is a clone */ + pl2303_vendor_read(0x9494, 0, serial, buf); + /* + * NOTE: Not sure if this read is really needed. + * The HX returns 0x00, the clone 0x02, but the Windows + * driver seems to ignore the value and continues. + */ + pl2303_vendor_write(0x0606, 0xaa, serial); + pl2303_vendor_read(0x8686, 0, serial, buf); + if (buf[0] != 0xaa) { + type = HX_CLONE; + type_str = "X/HX clone (limited functionality)"; + } else { + type = HX_TA; + type_str = "X/HX/TA"; + } + pl2303_vendor_write(0x0606, 0x00, serial); } else if (le16_to_cpu(serial->dev->descriptor.bcdDevice) == 0x400) { type = HXD_EA_RA_SA; @@ -305,8 +321,9 @@ static int pl2303_baudrate_encode_direct(int baud, enum pl2303_type type, { /* * NOTE: Only the values defined in baud_sup are supported ! - * => if unsupported values are set, the PL2303 seems to - * use 9600 baud (at least my PL2303X always does) + * => if unsupported values are set, the PL2303 uses 9600 baud instead + * => HX clones just don't work at unsupported baud rates < 115200 baud, + * for baud rates > 115200 they run at 115200 baud */ const int baud_sup[] = { 75, 150, 300, 600, 1200, 1800, 2400, 3600, 4800, 7200, 9600, 14400, 19200, 28800, 38400, @@ -316,14 +333,14 @@ static int pl2303_baudrate_encode_direct(int baud, enum pl2303_type type, * NOTE: With the exception of type_0/1 devices, the following * additional baud rates are supported (tested with HX rev. 3A only): * 110*, 56000*, 128000, 134400, 161280, 201600, 256000*, 268800, - * 403200, 806400. (*: not HX) + * 403200, 806400. (*: not HX and HX clones) * * Maximum values: HXD, TB: 12000000; HX, TA: 6000000; - * type_0+1: 1228800; RA: 921600; SA: 115200 + * type_0+1: 1228800; RA: 921600; HX clones, SA: 115200 * * As long as we are not using this encoding method for anything else - * than the type_0+1 and HX chips, there is no point in complicating - * the code to support them. + * than the type_0+1, HX and HX clone chips, there is no point in + * complicating the code to support them. */ int i; @@ -347,6 +364,8 @@ static int pl2303_baudrate_encode_direct(int baud, enum pl2303_type type, baud = min_t(int, baud, 6000000); else if (type == type_0 || type == type_1) baud = min_t(int, baud, 1228800); + else if (type == HX_CLONE) + baud = min_t(int, baud, 115200); /* Direct (standard) baud rate encoding method */ put_unaligned_le32(baud, buf); @@ -359,7 +378,8 @@ static int pl2303_baudrate_encode_divisor(int baud, enum pl2303_type type, /* * Divisor based baud rate encoding method * - * NOTE: it's not clear if the type_0/1 chips support this method + * NOTE: HX clones do NOT support this method. + * It's not clear if the type_0/1 chips support it. * * divisor = 12MHz * 32 / baudrate = 2^A * B * @@ -452,7 +472,7 @@ static void pl2303_encode_baudrate(struct tty_struct *tty, * 1) Direct method: encodes the baud rate value directly * => supported by all chip types * 2) Divisor based method: encodes a divisor to a base value (12MHz*32) - * => supported by HX chips (and likely not by type_0/1 chips) + * => not supported by HX clones (and likely type_0/1 chips) * * NOTE: Although the divisor based baud rate encoding method is much * more flexible, some of the standard baud rate values can not be @@ -460,7 +480,7 @@ static void pl2303_encode_baudrate(struct tty_struct *tty, * the device likely uses the same baud rate generator for both methods * so that there is likley no difference. */ - if (type == type_0 || type == type_1) + if (type == type_0 || type == type_1 || type == HX_CLONE) baud = pl2303_baudrate_encode_direct(baud, type, buf); else baud = pl2303_baudrate_encode_divisor(baud, type, buf); @@ -813,6 +833,7 @@ static void pl2303_break_ctl(struct tty_struct *tty, int break_state) result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0), BREAK_REQUEST, BREAK_REQUEST_TYPE, state, 0, NULL, 0, 100); + /* NOTE: HX clones don't support sending breaks, -EPIPE is returned */ if (result) dev_err(&port->dev, "error sending break = %d\n", result); } |