Re: [PATCH] bw-qcam: adds parameter aggressive to skip passive detection and directly attempt initialization
On Dec 5, 2007 9:37 AM, Alan Cox <[EMAIL PROTECTED]> wrote: > Although I would suggest that "aggressive" may not be the best term - I'm > not such of a good one however - skip_passive ? How about force_init? -- Brett Warden -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] bw-qcam: Adds module parameter 'aggressive' to skip polite auto-detection prior to direct initialization.
Sorry, forgot to copy back to the lists. On Dec 5, 2007 8:49 AM, Brett Warden <[EMAIL PROTECTED]> wrote: > On Dec 4, 2007 4:46 PM, Alan Cox <[EMAIL PROTECTED]> wrote: > > > > Someone still has a bw-qcam device ? > > Yes. I haven't found a better option for very-low-light, although I > admit I haven't looked in a long while. The last one I tried was an > OV518+, but of course that driver seems to have been abandoned. > > > The status polling ought to be rock solid - what values do you see ? > > It has been as high as 94-96, but after being connected, powered, and > used for a while, it drops sometimes into the 40s, but has even been > as low as 8-14. When it's that low, it never comes back up until > either I disconnect/reconnect the power, or I force the driver to > initialize it through this hack. Even after trying that again just > now, it's ranging from 24-33. > > -- > Brett Warden > -- Brett Warden -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] bw-qcam: adds parameter aggressive to skip passive detection and directly attempt initialization
On Dec 5, 2007 9:37 AM, Alan Cox [EMAIL PROTECTED] wrote: Although I would suggest that aggressive may not be the best term - I'm not such of a good one however - skip_passive ? How about force_init? -- Brett Warden -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] bw-qcam: Adds module parameter 'aggressive' to skip polite auto-detection prior to direct initialization.
Sorry, forgot to copy back to the lists. On Dec 5, 2007 8:49 AM, Brett Warden [EMAIL PROTECTED] wrote: On Dec 4, 2007 4:46 PM, Alan Cox [EMAIL PROTECTED] wrote: Someone still has a bw-qcam device ? Yes. I haven't found a better option for very-low-light, although I admit I haven't looked in a long while. The last one I tried was an OV518+, but of course that driver seems to have been abandoned. The status polling ought to be rock solid - what values do you see ? It has been as high as 94-96, but after being connected, powered, and used for a while, it drops sometimes into the 40s, but has even been as low as 8-14. When it's that low, it never comes back up until either I disconnect/reconnect the power, or I force the driver to initialize it through this hack. Even after trying that again just now, it's ranging from 24-33. -- Brett Warden -- Brett Warden -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] bw-qcam: use data_reverse instead of manually poking the control register
Fixes use of parport_write_control() to match the newer interface that
requires explicit parport_data_reverse() and parport_data_forward()
calls. This eliminates the following error message and restores the
original intended behavior:
parport0 (bw-qcam): use data_reverse for this!
Also increases threshold in qc_detect() from 300 to 400, as my camera
often results in a count of approx 330. Added a kernel error message
to indicate detection failure.
Signed-off-by: Brett T. Warden <[EMAIL PROTECTED]>
---
Thanks Ray and Randy for your comments, and for pointing out that I
needed to reset the port to forward mode!
diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c
index 7d47cbe..961e377 100644
--- a/drivers/media/video/bw-qcam.c
+++ b/drivers/media/video/bw-qcam.c
@@ -104,6 +104,17 @@ static inline void write_lpdata(struct
qcam_device *q, int d)
static inline void write_lpcontrol(struct qcam_device *q, int d)
{
+ if(0x20 & d) {
+ /* Set bidirectional mode to reverse (data in) */
+ parport_data_reverse(q->pport);
+ } else {
+ /* Set bidirectional mode to forward (data out) */
+ parport_data_forward(q->pport);
+ }
+
+ /* Now issue the regular port command, but strip out the
+* direction flag */
+ d &= ~0x20;
parport_write_control(q->pport, d);
}
@@ -344,10 +355,13 @@ static int qc_detect(struct qcam_device *q)
/* Be (even more) liberal in what you accept... */
/* if (count > 30 && count < 200) */
- if (count > 20 && count < 300)
+ if (count > 20 && count < 400)
+ {
return 1; /* found */
- else
+ } else {
+ printk(KERN_ERR "No Quickcam found on port %s\n",
q->pport->name);
return 0; /* not found */
+ }
}
--
Brett Warden
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] bw-qcam: use data_reverse instead of manually poking the control register
Fixes use of parport_write_control() to match the newer interface that
requires explicit parport_data_reverse() and parport_data_forward()
calls. This eliminates the following error message and restores the
original intended behavior:
parport0 (bw-qcam): use data_reverse for this!
Also increases threshold in qc_detect() from 300 to 400, as my camera
often results in a count of approx 330. Added a kernel error message
to indicate detection failure.
Signed-off-by: Brett T. Warden [EMAIL PROTECTED]
---
Thanks Ray and Randy for your comments, and for pointing out that I
needed to reset the port to forward mode!
diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c
index 7d47cbe..961e377 100644
--- a/drivers/media/video/bw-qcam.c
+++ b/drivers/media/video/bw-qcam.c
@@ -104,6 +104,17 @@ static inline void write_lpdata(struct
qcam_device *q, int d)
static inline void write_lpcontrol(struct qcam_device *q, int d)
{
+ if(0x20 d) {
+ /* Set bidirectional mode to reverse (data in) */
+ parport_data_reverse(q-pport);
+ } else {
+ /* Set bidirectional mode to forward (data out) */
+ parport_data_forward(q-pport);
+ }
+
+ /* Now issue the regular port command, but strip out the
+* direction flag */
+ d = ~0x20;
parport_write_control(q-pport, d);
}
@@ -344,10 +355,13 @@ static int qc_detect(struct qcam_device *q)
/* Be (even more) liberal in what you accept... */
/* if (count 30 count 200) */
- if (count 20 count 300)
+ if (count 20 count 400)
+ {
return 1; /* found */
- else
+ } else {
+ printk(KERN_ERR No Quickcam found on port %s\n,
q-pport-name);
return 0; /* not found */
+ }
}
--
Brett Warden
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] bw-qcam: use data_reverse instead of manually poking the control register
On 9/26/07, Ray Lee <[EMAIL PROTECTED]> wrote:
> On 9/26/07, Brett Warden <[EMAIL PROTECTED]> wrote:
> > On 9/26/07, Ray Lee <[EMAIL PROTECTED]> wrote:
> >
> > > Just as an aside, if you've tested this and it works, then there's no
> > > point to keep the write_lpcontrol even as a comment. Kill those four
> > > lines, and if someone's interested in what happened they'll just look
> > > at the file history.
> >
> > Point taken, thanks for the feedback.
> >
> > ---
> >
> > diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c
> > index 7d47cbe..0ba92e3 100644
> > --- a/drivers/media/video/bw-qcam.c
> > +++ b/drivers/media/video/bw-qcam.c
> > @@ -107,6 +107,11 @@ static inline void write_lpcontrol(struct
> > qcam_device *q, int d)
> > parport_write_control(q->pport, d);
> > }
> >
> > +static inline void reverse_port(struct qcam_device *q)
> > +{
> > + parport_data_reverse(q->pport);
> > +}
> > +
> > static int qc_waithand(struct qcam_device *q, int val);
> > static int qc_command(struct qcam_device *q, int command);
> > static int qc_readparam(struct qcam_device *q);
> > @@ -369,7 +374,7 @@ static void qc_reset(struct qcam_device *q)
> > break;
> >
> > case QC_ANY:
> > - write_lpcontrol(q, 0x20);
> > + reverse_port(q);
> > write_lpdata(q, 0x75);
> >
> > if (read_lpdata(q) != 0x75) {
> > @@ -512,10 +517,12 @@ static inline int qc_readbytes(struct
> > qcam_device *q, char buffer[])
> > switch (q->port_mode & QC_MODE_MASK)
> > {
> > case QC_BIDIR: /* Bi-directional Port */
> > - write_lpcontrol(q, 0x26);
> > + reverse_port(q);
> > + write_lpcontrol(q, 0x6);
> > lo = (qc_waithand2(q, 1) >> 1);
> > hi = (read_lpstatus(q) >> 3) & 0x1f;
> > - write_lpcontrol(q, 0x2e);
> > + reverse_port(q);
> > + write_lpcontrol(q, 0xe);
> > lo2 = (qc_waithand2(q, 0) >> 1);
> > hi2 = (read_lpstatus(q) >> 3) & 0x1f;
> > switch (q->bpp)
> > @@ -613,10 +620,13 @@ static long qc_capture(struct qcam_device * q,
> > char __user *buf, unsigned long l
> >
> > if ((q->port_mode & QC_MODE_MASK) == QC_BIDIR)
> > {
> > - write_lpcontrol(q, 0x2e); /* turn port around */
> > - write_lpcontrol(q, 0x26);
> > + reverse_port(q);/* turn port around
> > */
> > + write_lpcontrol(q, 0xe);
> > + reverse_port(q);
> > + write_lpcontrol(q, 0x6);
> > (void) qc_waithand(q, 1);
> > - write_lpcontrol(q, 0x2e);
> > + reverse_port(q);
> > + write_lpcontrol(q, 0xe);
> > (void) qc_waithand(q, 0);
> > }
>
> Better, and do you have time for two (possibly stupid) questions? In
> each of the last cases it looks like the transformation is from a
> write_lpcontrol -> reverse_port and a write_lpcontrol (old address -
> 0x20). Except the first one, which merely has the reverse_port. One
> would think that there should be a write_lpcontrol(q, 0x0); after that
> one.
>
> Also, is the reverse port sticky, or does it only apply to the next
> write? If it's only the next, then maybe a different name would be
> better. If it's sticky, then I think the code is wrong...
In response to Randy's and your questions, here's what I understand:
The error message comes from parport_pc_write_control in
include/linux/parport_pc.h, which is called by bw-qcam's
write_lpcontrol():
static __inline__ void parport_pc_write_control (struct parport *p,
unsigned char d)
{
const unsigned char wm = (PARPORT_CONTROL_STROBE |
PARPORT_CONTROL_AUTOFD |
PARPORT_CONTROL_INIT |
PARPORT_CONTROL_SELECT);
/* Take this out when drivers have adapted to newer interface. */
if (d & 0x20) {
printk (KERN_DEBUG "%s (%s): use data_reverse for this!\n",
p->name, p->cad->name);
parport_pc_data_reverse (p);
}
__parport_pc_frob_control (p, wm, d & wm);
}
Re: [PATCH] bw-qcam: use data_reverse instead of manually poking the control register
On 9/26/07, Ray Lee <[EMAIL PROTECTED]> wrote:
> Just as an aside, if you've tested this and it works, then there's no
> point to keep the write_lpcontrol even as a comment. Kill those four
> lines, and if someone's interested in what happened they'll just look
> at the file history.
Point taken, thanks for the feedback.
---
diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c
index 7d47cbe..0ba92e3 100644
--- a/drivers/media/video/bw-qcam.c
+++ b/drivers/media/video/bw-qcam.c
@@ -107,6 +107,11 @@ static inline void write_lpcontrol(struct
qcam_device *q, int d)
parport_write_control(q->pport, d);
}
+static inline void reverse_port(struct qcam_device *q)
+{
+ parport_data_reverse(q->pport);
+}
+
static int qc_waithand(struct qcam_device *q, int val);
static int qc_command(struct qcam_device *q, int command);
static int qc_readparam(struct qcam_device *q);
@@ -369,7 +374,7 @@ static void qc_reset(struct qcam_device *q)
break;
case QC_ANY:
- write_lpcontrol(q, 0x20);
+ reverse_port(q);
write_lpdata(q, 0x75);
if (read_lpdata(q) != 0x75) {
@@ -512,10 +517,12 @@ static inline int qc_readbytes(struct
qcam_device *q, char buffer[])
switch (q->port_mode & QC_MODE_MASK)
{
case QC_BIDIR: /* Bi-directional Port */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
lo = (qc_waithand2(q, 1) >> 1);
hi = (read_lpstatus(q) >> 3) & 0x1f;
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
lo2 = (qc_waithand2(q, 0) >> 1);
hi2 = (read_lpstatus(q) >> 3) & 0x1f;
switch (q->bpp)
@@ -613,10 +620,13 @@ static long qc_capture(struct qcam_device * q,
char __user *buf, unsigned long l
if ((q->port_mode & QC_MODE_MASK) == QC_BIDIR)
{
- write_lpcontrol(q, 0x2e); /* turn port around */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);/* turn port around */
+ write_lpcontrol(q, 0xe);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
(void) qc_waithand(q, 1);
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
(void) qc_waithand(q, 0);
}
--
Brett Warden
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[PATCH] bw-qcam: use data_reverse instead of manually poking the control register
Appeases the warning "parport0 (bw-qcam): use data_reverse for this!"
Signed-off-by: Brett T. Warden <[EMAIL PROTECTED]>
---
It seems to work fine with my Quickcam under 2.6.22.
diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c
index 7d47cbe..01e47ed 100644
--- a/drivers/media/video/bw-qcam.c
+++ b/drivers/media/video/bw-qcam.c
@@ -107,6 +107,11 @@ static inline void write_lpcontrol(struct
qcam_device *q, int d)
parport_write_control(q->pport, d);
}
+static inline void reverse_port(struct qcam_device *q)
+{
+ parport_data_reverse(q->pport);
+}
+
static int qc_waithand(struct qcam_device *q, int val);
static int qc_command(struct qcam_device *q, int command);
static int qc_readparam(struct qcam_device *q);
@@ -369,7 +374,11 @@ static void qc_reset(struct qcam_device *q)
break;
case QC_ANY:
- write_lpcontrol(q, 0x20);
+ /*
+* Replaced with reverse_port
+* write_lpcontrol(q, 0x20);
+*/
+ reverse_port(q);
write_lpdata(q, 0x75);
if (read_lpdata(q) != 0x75) {
@@ -512,10 +521,12 @@ static inline int qc_readbytes(struct
qcam_device *q, char buffer[])
switch (q->port_mode & QC_MODE_MASK)
{
case QC_BIDIR: /* Bi-directional Port */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
lo = (qc_waithand2(q, 1) >> 1);
hi = (read_lpstatus(q) >> 3) & 0x1f;
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
lo2 = (qc_waithand2(q, 0) >> 1);
hi2 = (read_lpstatus(q) >> 3) & 0x1f;
switch (q->bpp)
@@ -613,10 +624,13 @@ static long qc_capture(struct qcam_device * q,
char __user *buf, unsigned long l
if ((q->port_mode & QC_MODE_MASK) == QC_BIDIR)
{
- write_lpcontrol(q, 0x2e); /* turn port around */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);/* turn port around */
+ write_lpcontrol(q, 0xe);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
(void) qc_waithand(q, 1);
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
(void) qc_waithand(q, 0);
}
--
Brett Warden
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[PATCH] bw-qcam: use data_reverse instead of manually poking the control register
Appeases the warning parport0 (bw-qcam): use data_reverse for this!
Signed-off-by: Brett T. Warden [EMAIL PROTECTED]
---
It seems to work fine with my Quickcam under 2.6.22.
diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c
index 7d47cbe..01e47ed 100644
--- a/drivers/media/video/bw-qcam.c
+++ b/drivers/media/video/bw-qcam.c
@@ -107,6 +107,11 @@ static inline void write_lpcontrol(struct
qcam_device *q, int d)
parport_write_control(q-pport, d);
}
+static inline void reverse_port(struct qcam_device *q)
+{
+ parport_data_reverse(q-pport);
+}
+
static int qc_waithand(struct qcam_device *q, int val);
static int qc_command(struct qcam_device *q, int command);
static int qc_readparam(struct qcam_device *q);
@@ -369,7 +374,11 @@ static void qc_reset(struct qcam_device *q)
break;
case QC_ANY:
- write_lpcontrol(q, 0x20);
+ /*
+* Replaced with reverse_port
+* write_lpcontrol(q, 0x20);
+*/
+ reverse_port(q);
write_lpdata(q, 0x75);
if (read_lpdata(q) != 0x75) {
@@ -512,10 +521,12 @@ static inline int qc_readbytes(struct
qcam_device *q, char buffer[])
switch (q-port_mode QC_MODE_MASK)
{
case QC_BIDIR: /* Bi-directional Port */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
lo = (qc_waithand2(q, 1) 1);
hi = (read_lpstatus(q) 3) 0x1f;
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
lo2 = (qc_waithand2(q, 0) 1);
hi2 = (read_lpstatus(q) 3) 0x1f;
switch (q-bpp)
@@ -613,10 +624,13 @@ static long qc_capture(struct qcam_device * q,
char __user *buf, unsigned long l
if ((q-port_mode QC_MODE_MASK) == QC_BIDIR)
{
- write_lpcontrol(q, 0x2e); /* turn port around */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);/* turn port around */
+ write_lpcontrol(q, 0xe);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
(void) qc_waithand(q, 1);
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
(void) qc_waithand(q, 0);
}
--
Brett Warden
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] bw-qcam: use data_reverse instead of manually poking the control register
On 9/26/07, Ray Lee [EMAIL PROTECTED] wrote:
Just as an aside, if you've tested this and it works, then there's no
point to keep the write_lpcontrol even as a comment. Kill those four
lines, and if someone's interested in what happened they'll just look
at the file history.
Point taken, thanks for the feedback.
---
diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c
index 7d47cbe..0ba92e3 100644
--- a/drivers/media/video/bw-qcam.c
+++ b/drivers/media/video/bw-qcam.c
@@ -107,6 +107,11 @@ static inline void write_lpcontrol(struct
qcam_device *q, int d)
parport_write_control(q-pport, d);
}
+static inline void reverse_port(struct qcam_device *q)
+{
+ parport_data_reverse(q-pport);
+}
+
static int qc_waithand(struct qcam_device *q, int val);
static int qc_command(struct qcam_device *q, int command);
static int qc_readparam(struct qcam_device *q);
@@ -369,7 +374,7 @@ static void qc_reset(struct qcam_device *q)
break;
case QC_ANY:
- write_lpcontrol(q, 0x20);
+ reverse_port(q);
write_lpdata(q, 0x75);
if (read_lpdata(q) != 0x75) {
@@ -512,10 +517,12 @@ static inline int qc_readbytes(struct
qcam_device *q, char buffer[])
switch (q-port_mode QC_MODE_MASK)
{
case QC_BIDIR: /* Bi-directional Port */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
lo = (qc_waithand2(q, 1) 1);
hi = (read_lpstatus(q) 3) 0x1f;
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
lo2 = (qc_waithand2(q, 0) 1);
hi2 = (read_lpstatus(q) 3) 0x1f;
switch (q-bpp)
@@ -613,10 +620,13 @@ static long qc_capture(struct qcam_device * q,
char __user *buf, unsigned long l
if ((q-port_mode QC_MODE_MASK) == QC_BIDIR)
{
- write_lpcontrol(q, 0x2e); /* turn port around */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);/* turn port around */
+ write_lpcontrol(q, 0xe);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
(void) qc_waithand(q, 1);
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
(void) qc_waithand(q, 0);
}
--
Brett Warden
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] bw-qcam: use data_reverse instead of manually poking the control register
On 9/26/07, Ray Lee [EMAIL PROTECTED] wrote:
On 9/26/07, Brett Warden [EMAIL PROTECTED] wrote:
On 9/26/07, Ray Lee [EMAIL PROTECTED] wrote:
Just as an aside, if you've tested this and it works, then there's no
point to keep the write_lpcontrol even as a comment. Kill those four
lines, and if someone's interested in what happened they'll just look
at the file history.
Point taken, thanks for the feedback.
---
diff --git a/drivers/media/video/bw-qcam.c b/drivers/media/video/bw-qcam.c
index 7d47cbe..0ba92e3 100644
--- a/drivers/media/video/bw-qcam.c
+++ b/drivers/media/video/bw-qcam.c
@@ -107,6 +107,11 @@ static inline void write_lpcontrol(struct
qcam_device *q, int d)
parport_write_control(q-pport, d);
}
+static inline void reverse_port(struct qcam_device *q)
+{
+ parport_data_reverse(q-pport);
+}
+
static int qc_waithand(struct qcam_device *q, int val);
static int qc_command(struct qcam_device *q, int command);
static int qc_readparam(struct qcam_device *q);
@@ -369,7 +374,7 @@ static void qc_reset(struct qcam_device *q)
break;
case QC_ANY:
- write_lpcontrol(q, 0x20);
+ reverse_port(q);
write_lpdata(q, 0x75);
if (read_lpdata(q) != 0x75) {
@@ -512,10 +517,12 @@ static inline int qc_readbytes(struct
qcam_device *q, char buffer[])
switch (q-port_mode QC_MODE_MASK)
{
case QC_BIDIR: /* Bi-directional Port */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
lo = (qc_waithand2(q, 1) 1);
hi = (read_lpstatus(q) 3) 0x1f;
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
lo2 = (qc_waithand2(q, 0) 1);
hi2 = (read_lpstatus(q) 3) 0x1f;
switch (q-bpp)
@@ -613,10 +620,13 @@ static long qc_capture(struct qcam_device * q,
char __user *buf, unsigned long l
if ((q-port_mode QC_MODE_MASK) == QC_BIDIR)
{
- write_lpcontrol(q, 0x2e); /* turn port around */
- write_lpcontrol(q, 0x26);
+ reverse_port(q);/* turn port around
*/
+ write_lpcontrol(q, 0xe);
+ reverse_port(q);
+ write_lpcontrol(q, 0x6);
(void) qc_waithand(q, 1);
- write_lpcontrol(q, 0x2e);
+ reverse_port(q);
+ write_lpcontrol(q, 0xe);
(void) qc_waithand(q, 0);
}
Better, and do you have time for two (possibly stupid) questions? In
each of the last cases it looks like the transformation is from a
write_lpcontrol - reverse_port and a write_lpcontrol (old address -
0x20). Except the first one, which merely has the reverse_port. One
would think that there should be a write_lpcontrol(q, 0x0); after that
one.
Also, is the reverse port sticky, or does it only apply to the next
write? If it's only the next, then maybe a different name would be
better. If it's sticky, then I think the code is wrong...
In response to Randy's and your questions, here's what I understand:
The error message comes from parport_pc_write_control in
include/linux/parport_pc.h, which is called by bw-qcam's
write_lpcontrol():
static __inline__ void parport_pc_write_control (struct parport *p,
unsigned char d)
{
const unsigned char wm = (PARPORT_CONTROL_STROBE |
PARPORT_CONTROL_AUTOFD |
PARPORT_CONTROL_INIT |
PARPORT_CONTROL_SELECT);
/* Take this out when drivers have adapted to newer interface. */
if (d 0x20) {
printk (KERN_DEBUG %s (%s): use data_reverse for this!\n,
p-name, p-cad-name);
parport_pc_data_reverse (p);
}
__parport_pc_frob_control (p, wm, d wm);
}
The mask wm works out to 0x0f, so first it calls
parport_pc_data_reverse(), then masks off the high nibble with the
reverse flag and makes the regular call.
Looking at that more carefully, I'm not sure whether I need to add the
write_lpcontrol(q, 0) after the first call. Other than that, I believe
I'm following the same procedure.
As for whether data_reverse is sticky, I don't know... I'll see what I
can find out.
--
Brett Warden
-
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
