On 2013-03-26 22:01, H Hartley Sweeten wrote:
This variable in the private data is not necessary. Remove it.
Signed-off-by: H Hartley Sweeten <hsweeten@xxxxxxxxxxxxxxxxxxx>
Cc: Ian Abbott <abbotti@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/staging/comedi/drivers/rtd520.c | 15 ++++-----------
1 file changed, 4 insertions(+), 11 deletions(-)
diff --git a/drivers/staging/comedi/drivers/rtd520.c b/drivers/staging/comedi/drivers/rtd520.c
index 6902353..70e93c0 100644
--- a/drivers/staging/comedi/drivers/rtd520.c
+++ b/drivers/staging/comedi/drivers/rtd520.c
@@ -412,9 +412,6 @@ struct rtdPrivate {
/* timer gate (when enabled) */
u8 utcGate[4]; /* 1 extra allows simple range check */
- /* shadow registers affect other registers, but can't be read back */
- /* The macros below update these on writes */
- u8 utcCtrl[4]; /* crtl mode for 3 utc + read back */
unsigned fifoLen;
};
@@ -1319,14 +1316,10 @@ static void rtd_init_board(struct comedi_device *dev)
writel(0, devpriv->las0 + LAS0_DAC2_RESET);
/* clear digital IO fifo */
writew(0, devpriv->las0 + LAS0_DIO_STATUS);
- devpriv->utcCtrl[0] = (0 << 6) | 0x30;
- devpriv->utcCtrl[1] = (1 << 6) | 0x30;
- devpriv->utcCtrl[2] = (2 << 6) | 0x30;
- devpriv->utcCtrl[3] = (3 << 6) | 0x00;
- writeb(devpriv->utcCtrl[0], devpriv->las0 + LAS0_UTC_CTRL);
- writeb(devpriv->utcCtrl[1], devpriv->las0 + LAS0_UTC_CTRL);
- writeb(devpriv->utcCtrl[2], devpriv->las0 + LAS0_UTC_CTRL);
- writeb(devpriv->utcCtrl[3], devpriv->las0 + LAS0_UTC_CTRL);
+ writeb((0 << 6) | 0x30, devpriv->las0 + LAS0_UTC_CTRL);
+ writeb((1 << 6) | 0x30, devpriv->las0 + LAS0_UTC_CTRL);
+ writeb((2 << 6) | 0x30, devpriv->las0 + LAS0_UTC_CTRL);
+ writeb((3 << 6) | 0x00, devpriv->las0 + LAS0_UTC_CTRL);
/* TODO: set user out source ??? */
}
This is not a comment on the patch, but a comment on the operation. The
first three writeb()s set each of the 3 "8254" counter channels
(selected by bits 7..6) to mode 0 (bits 3..1), binary count (bit 0),
with the 16-bit counter accessed lsb first (bits 5..4). The remaining
writeb() is a bit mysterious. It's a "read-back" command (bits 7..6 =
3), latching the count and status (bits 6 and 5, both negative logic),
but with no channels selected (bits 3, 2 and 1 for channels 2, 1 and 0,
respectively). Because it doesn't select any channels it's probably a
bit of a no-op and therefore unnecessary.
--
-=( Ian Abbott @ MEV Ltd. E-mail: <abbotti@xxxxxxxxx> )=-
-=( Tel: +44 (0)161 477 1898 FAX: +44 (0)161 718 3587 )=-
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