Revert "usb: pl2303: increase the allowed baud rate range for the divisor based encoding method"
This reverts commit b5c16c6a031c52cc4b7dda6c3de46462fbc92eab.
Revert all of the pl2303 changes that went into 3.12-rc1 and -rc2 as
they cause regressions on some versions of the chip. This will all be
revisited for later kernel versions when we can figure out how to handle
this in a way that does not break working devices.
Reported-by: Mika Westerberg <email@example.com>
Cc: Frank Schäfer <firstname.lastname@example.org>
Acked-by: Johan Hovold <email@example.com>
Signed-off-by: Greg Kroah-Hartman <firstname.lastname@example.org>
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index 61c9f9d..693ed7e 100644
@@ -324,20 +324,12 @@
unsigned int A, B;
- * NOTE: The Windows driver allows maximum baud rates of 110% of the
- * specified maximium value.
- * Quick tests with early (2004) HX (rev. A) chips suggest, that even
- * higher baud rates (up to the maximum of 24M baud !) are working fine,
- * but that should really be tested carefully in "real life" scenarios
- * before removing the upper limit completely.
- * Baud rates smaller than the specified 75 baud are definitely working
- * fine.
+ /* Respect the specified baud rate limits */
+ baud = max_t(int, baud, 75);
if (type == HX)
- baud = min_t(int, baud, 6000000 * 1.1);
+ baud = min_t(int, baud, 6000000);
- baud = min_t(int, baud, 1228800 * 1.1);
+ baud = min_t(int, baud, 1228800);
/* Determine factors A and B */
A = 0;
B = 12000000 * 32 / baud; /* 12MHz */