Clean up baud-rate handling somewhat.
Signed-off-by: Johan Hovold <jhovold@xxxxxxxxx>
---
drivers/usb/serial/pl2303.c | 90 +++++++++++++++++++++------------------------
1 file changed, 41 insertions(+), 49 deletions(-)
diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c
index c15d64d..dd59c64 100644
--- a/drivers/usb/serial/pl2303.c
+++ b/drivers/usb/serial/pl2303.c
@@ -29,6 +29,7 @@
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
+#include <asm/unaligned.h>
#include "pl2303.h"
/*
@@ -275,65 +276,56 @@ static void pl2303_encode_baudrate(struct tty_struct *tty,
struct usb_serial *serial = port->serial;
struct pl2303_serial_private *spriv = usb_get_serial_data(serial);
int baud;
- int baud_floor, baud_ceil;
- int k;
+ int i;
- /* NOTE: Only the values defined in baud_sup are supported !
+ /*
+ * 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)
*/
baud = tty_get_baud_rate(tty);
dev_dbg(&port->dev, "baud requested = %d\n", baud);
- if (baud) {
- /* Set baudrate to nearest supported value */
- for (k=0; k<ARRAY_SIZE(baud_sup); k++) {
- if (baud_sup[k] / baud) {
- baud_ceil = baud_sup[k];
- if (k==0) {
- baud = baud_ceil;
- } else {
- baud_floor = baud_sup[k-1];
- if ((baud_ceil % baud)
- > (baud % baud_floor))
- baud = baud_floor;
- else
- baud = baud_ceil;
- }
- break;
- }
- }
- if (baud > 1228800) {
- /* type_0, type_1 only support up to 1228800 baud */
- if (spriv->type != HX)
- baud = 1228800;
- else if (baud > 6000000)
- baud = 6000000;
- }
- dev_dbg(&port->dev, "baud set = %d\n", baud);
- if (baud <= 115200) {
- buf[0] = baud & 0xff;
- buf[1] = (baud >> 8) & 0xff;
- buf[2] = (baud >> 16) & 0xff;
- buf[3] = (baud >> 24) & 0xff;
- } else {
- /* apparently the formula for higher speeds is:
- * baudrate = 12M * 32 / (2^buf[1]) / buf[0]
- */
- unsigned tmp = 12*1000*1000*32 / baud;
- buf[3] = 0x80;
- buf[2] = 0;
- buf[1] = (tmp >= 256);
- while (tmp >= 256) {
- tmp >>= 2;
- buf[1] <<= 1;
- }
- buf[0] = tmp;
+ if (!baud)
+ return;
+
+ /* Set baudrate to nearest supported value */
+ for (i = 0; i < ARRAY_SIZE(baud_sup); ++i) {
+ if (baud_sup[i] > baud)
+ break;
+ }
+
+ if (i == ARRAY_SIZE(baud_sup))
+ baud = baud_sup[i - 1];
+ else if (i > 0 && (baud_sup[i] - baud) > (baud - baud_sup[i - 1]))
+ baud = baud_sup[i - 1];
+ else
+ baud = baud_sup[i];
+
+ /* type_0, type_1 only support up to 1228800 baud */
+ if (spriv->type != HX)
+ baud = max_t(int, baud, 1228800);
+
+ if (baud <= 115200) {
+ put_unaligned_le32(baud, buf);
+ } else {
+ /*
+ * Apparently the formula for higher speeds is:
+ * baudrate = 12M * 32 / (2^buf[1]) / buf[0]
+ */
+ unsigned tmp = 12000000 * 32 / baud;
+ buf[3] = 0x80;
+ buf[2] = 0;
+ buf[1] = (tmp >= 256);
+ while (tmp >= 256) {
+ tmp >>= 2;
+ buf[1] <<= 1;
}
+ buf[0] = tmp;
}
/* Save resulting baud rate */
- if (baud)
- tty_encode_baud_rate(tty, baud, baud);
+ tty_encode_baud_rate(tty, baud, baud);
+ dev_dbg(&port->dev, "baud set = %d\n", baud);
}
static void pl2303_set_termios(struct tty_struct *tty,
--
1.8.2.1
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