* [PATCH] drm/ast: fixed reading monitor EDID not stable issue
@ 2018-10-30 6:00 Y.C. Chen
2018-10-30 13:01 ` Ilia Mirkin
2018-10-31 1:31 ` [[PATCH v2]] " Y.C. Chen
0 siblings, 2 replies; 7+ messages in thread
From: Y.C. Chen @ 2018-10-30 6:00 UTC (permalink / raw)
To: dri-devel; +Cc: airlied, eich, benh, stable, daniel, yc_chen
From: "Y.C. Chen" <yc_chen@aspeedtech.com>
over-sample data to increase the stability with some specific monitors
Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com>
---
drivers/gpu/drm/ast/ast_mode.c | 32 ++++++++++++++++++++++++++------
1 file changed, 26 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 5e77d45..22e80c0 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -972,9 +972,19 @@ static int get_clock(void *i2c_priv)
{
struct ast_i2c_chan *i2c = i2c_priv;
struct ast_private *ast = i2c->dev->dev_private;
- uint32_t val;
+ volatile uint32_t val, val2, count;
+
+ count = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ do {
+ val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ if (val == val2) count++;
+ else {
+ count = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ }
+ } while (count < 5);
- val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4;
return val & 1 ? 1 : 0;
}
@@ -982,9 +992,19 @@ static int get_data(void *i2c_priv)
{
struct ast_i2c_chan *i2c = i2c_priv;
struct ast_private *ast = i2c->dev->dev_private;
- uint32_t val;
+ volatile uint32_t val, val2, count;
+
+ count = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ do {
+ val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ if (val == val2) count++;
+ else {
+ count = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ }
+ } while (count < 5);
- val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5;
return val & 1 ? 1 : 0;
}
@@ -997,7 +1017,7 @@ static void set_clock(void *i2c_priv, int clock)
for (i = 0; i < 0x10000; i++) {
ujcrb7 = ((clock & 0x01) ? 0 : 1);
- ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfe, ujcrb7);
+ ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf4, ujcrb7);
jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x01);
if (ujcrb7 == jtemp)
break;
@@ -1013,7 +1033,7 @@ static void set_data(void *i2c_priv, int data)
for (i = 0; i < 0x10000; i++) {
ujcrb7 = ((data & 0x01) ? 0 : 1) << 2;
- ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfb, ujcrb7);
+ ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf1, ujcrb7);
jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x04);
if (ujcrb7 == jtemp)
break;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [PATCH] drm/ast: fixed reading monitor EDID not stable issue
2018-10-30 6:00 [PATCH] drm/ast: fixed reading monitor EDID not stable issue Y.C. Chen
@ 2018-10-30 13:01 ` Ilia Mirkin
2018-10-31 1:31 ` [[PATCH v2]] " Y.C. Chen
1 sibling, 0 replies; 7+ messages in thread
From: Ilia Mirkin @ 2018-10-30 13:01 UTC (permalink / raw)
To: yacheng600221; +Cc: dri-devel, # 3.9+, eich, Dave Airlie
On Tue, Oct 30, 2018 at 4:24 AM Y.C. Chen <yacheng600221@gmail.com> wrote:
>
> From: "Y.C. Chen" <yc_chen@aspeedtech.com>
>
> over-sample data to increase the stability with some specific monitors
>
> Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com>
> ---
> drivers/gpu/drm/ast/ast_mode.c | 32 ++++++++++++++++++++++++++------
> 1 file changed, 26 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
> index 5e77d45..22e80c0 100644
> --- a/drivers/gpu/drm/ast/ast_mode.c
> +++ b/drivers/gpu/drm/ast/ast_mode.c
> @@ -972,9 +972,19 @@ static int get_clock(void *i2c_priv)
> {
> struct ast_i2c_chan *i2c = i2c_priv;
> struct ast_private *ast = i2c->dev->dev_private;
> - uint32_t val;
> + volatile uint32_t val, val2, count;
> +
> + count = 0;
> + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
> + do {
> + val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
> + if (val == val2) count++;
> + else {
> + count = 0;
> + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
> + }
> + } while (count < 5);
This can lead to an infinite loop if there's no stable output, no? I
think those are frowned upon in the kernel...
Cheers,
-ilia
^ permalink raw reply [flat|nested] 7+ messages in thread* [[PATCH v2]] drm/ast: fixed reading monitor EDID not stable issue
2018-10-30 6:00 [PATCH] drm/ast: fixed reading monitor EDID not stable issue Y.C. Chen
2018-10-30 13:01 ` Ilia Mirkin
@ 2018-10-31 1:31 ` Y.C. Chen
2018-11-22 1:15 ` Dave Airlie
2018-11-22 3:56 ` [PATCH v3] " Y.C. Chen
1 sibling, 2 replies; 7+ messages in thread
From: Y.C. Chen @ 2018-10-31 1:31 UTC (permalink / raw)
To: dri-devel; +Cc: airlied, eich, imirkin, yc_chen, stable
From: "Y.C. Chen" <yc_chen@aspeedtech.com>
v1: over-sample data to increase the stability with some specific monitors
v2: refine to avoid infinite loop
Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com>
---
drivers/gpu/drm/ast/ast_mode.c | 34 ++++++++++++++++++++++++++++------
1 file changed, 28 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 5e77d45..092e9a7 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -972,9 +972,20 @@ static int get_clock(void *i2c_priv)
{
struct ast_i2c_chan *i2c = i2c_priv;
struct ast_private *ast = i2c->dev->dev_private;
- uint32_t val;
+ volatile uint32_t val, val2, count, pass;
+
+ count = 0;
+ pass = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ do {
+ val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ if (val == val2) pass++;
+ else {
+ pass = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ }
+ } while ((pass < 5) && (count++ < 0x10000));
- val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4;
return val & 1 ? 1 : 0;
}
@@ -982,9 +993,20 @@ static int get_data(void *i2c_priv)
{
struct ast_i2c_chan *i2c = i2c_priv;
struct ast_private *ast = i2c->dev->dev_private;
- uint32_t val;
+ volatile uint32_t val, val2, count, pass;
+
+ count = 0;
+ pass = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ do {
+ val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ if (val == val2) pass++;
+ else {
+ pass = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ }
+ } while ((pass < 5) && (count++ < 0x10000));
- val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5;
return val & 1 ? 1 : 0;
}
@@ -997,7 +1019,7 @@ static void set_clock(void *i2c_priv, int clock)
for (i = 0; i < 0x10000; i++) {
ujcrb7 = ((clock & 0x01) ? 0 : 1);
- ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfe, ujcrb7);
+ ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf4, ujcrb7);
jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x01);
if (ujcrb7 == jtemp)
break;
@@ -1013,7 +1035,7 @@ static void set_data(void *i2c_priv, int data)
for (i = 0; i < 0x10000; i++) {
ujcrb7 = ((data & 0x01) ? 0 : 1) << 2;
- ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfb, ujcrb7);
+ ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf1, ujcrb7);
jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x04);
if (ujcrb7 == jtemp)
break;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [[PATCH v2]] drm/ast: fixed reading monitor EDID not stable issue
2018-10-31 1:31 ` [[PATCH v2]] " Y.C. Chen
@ 2018-11-22 1:15 ` Dave Airlie
2018-11-22 1:42 ` 陳雅正
2018-11-22 3:56 ` [PATCH v3] " Y.C. Chen
1 sibling, 1 reply; 7+ messages in thread
From: Dave Airlie @ 2018-11-22 1:15 UTC (permalink / raw)
To: yacheng600221; +Cc: dri-devel, Dave Airlie, stable, Egbert Eich
On Wed, 31 Oct 2018 at 18:12, Y.C. Chen <yacheng600221@gmail.com> wrote:
>
> From: "Y.C. Chen" <yc_chen@aspeedtech.com>
>
> v1: over-sample data to increase the stability with some specific monitors
> v2: refine to avoid infinite loop
This contains at least 4 whitespace breakages (val =) in a few
places, also why the volatiles, I don't think they make much sense
here, have you verified they are required?
Dave.
>
> Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com>
> ---
> drivers/gpu/drm/ast/ast_mode.c | 34 ++++++++++++++++++++++++++++------
> 1 file changed, 28 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
> index 5e77d45..092e9a7 100644
> --- a/drivers/gpu/drm/ast/ast_mode.c
> +++ b/drivers/gpu/drm/ast/ast_mode.c
> @@ -972,9 +972,20 @@ static int get_clock(void *i2c_priv)
> {
> struct ast_i2c_chan *i2c = i2c_priv;
> struct ast_private *ast = i2c->dev->dev_private;
> - uint32_t val;
> + volatile uint32_t val, val2, count, pass;
> +
> + count = 0;
> + pass = 0;
> + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
> + do {
> + val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
> + if (val == val2) pass++;
> + else {
> + pass = 0;
> + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
> + }
> + } while ((pass < 5) && (count++ < 0x10000));
>
> - val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4;
> return val & 1 ? 1 : 0;
> }
>
> @@ -982,9 +993,20 @@ static int get_data(void *i2c_priv)
> {
> struct ast_i2c_chan *i2c = i2c_priv;
> struct ast_private *ast = i2c->dev->dev_private;
> - uint32_t val;
> + volatile uint32_t val, val2, count, pass;
> +
> + count = 0;
> + pass = 0;
> + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
> + do {
> + val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
> + if (val == val2) pass++;
> + else {
> + pass = 0;
> + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
> + }
> + } while ((pass < 5) && (count++ < 0x10000));
>
> - val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5;
> return val & 1 ? 1 : 0;
> }
>
> @@ -997,7 +1019,7 @@ static void set_clock(void *i2c_priv, int clock)
>
> for (i = 0; i < 0x10000; i++) {
> ujcrb7 = ((clock & 0x01) ? 0 : 1);
> - ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfe, ujcrb7);
> + ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf4, ujcrb7);
> jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x01);
> if (ujcrb7 == jtemp)
> break;
> @@ -1013,7 +1035,7 @@ static void set_data(void *i2c_priv, int data)
>
> for (i = 0; i < 0x10000; i++) {
> ujcrb7 = ((data & 0x01) ? 0 : 1) << 2;
> - ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfb, ujcrb7);
> + ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf1, ujcrb7);
> jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x04);
> if (ujcrb7 == jtemp)
> break;
> --
> 1.8.3.1
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [[PATCH v2]] drm/ast: fixed reading monitor EDID not stable issue
2018-11-22 1:15 ` Dave Airlie
@ 2018-11-22 1:42 ` 陳雅正
2018-11-22 2:48 ` Dave Airlie
0 siblings, 1 reply; 7+ messages in thread
From: 陳雅正 @ 2018-11-22 1:42 UTC (permalink / raw)
To: airlied; +Cc: airlied, stable, dri-devel, eich
[-- Attachment #1.1: Type: text/plain, Size: 4527 bytes --]
Hi Dave,
Thanks for your feedback. No issue found actually if I remove "volatile" on
my platform. In my experience, if the value is volatile, adding "volatile"
will be safer and no harm, that is why I add it by default. If you think it
is not necessary, it's ok for me to remove it.
Regards,
Y.C. Chen
Dave Airlie <airlied@gmail.com> 於 2018年11月22日 週四 上午9:15寫道：
> On Wed, 31 Oct 2018 at 18:12, Y.C. Chen <yacheng600221@gmail.com> wrote:
> >
> > From: "Y.C. Chen" <yc_chen@aspeedtech.com>
> >
> > v1: over-sample data to increase the stability with some specific
> monitors
> > v2: refine to avoid infinite loop
>
> This contains at least 4 whitespace breakages (val =) in a few
> places, also why the volatiles, I don't think they make much sense
> here, have you verified they are required?
>
> Dave.
>
> >
> > Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com>
> > ---
> > drivers/gpu/drm/ast/ast_mode.c | 34 ++++++++++++++++++++++++++++------
> > 1 file changed, 28 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/ast/ast_mode.c
> b/drivers/gpu/drm/ast/ast_mode.c
> > index 5e77d45..092e9a7 100644
> > --- a/drivers/gpu/drm/ast/ast_mode.c
> > +++ b/drivers/gpu/drm/ast/ast_mode.c
> > @@ -972,9 +972,20 @@ static int get_clock(void *i2c_priv)
> > {
> > struct ast_i2c_chan *i2c = i2c_priv;
> > struct ast_private *ast = i2c->dev->dev_private;
> > - uint32_t val;
> > + volatile uint32_t val, val2, count, pass;
> > +
> > + count = 0;
> > + pass = 0;
> > + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7,
> 0x10) >> 4) & 0x01;
> > + do {
> > + val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT,
> 0xb7, 0x10) >> 4) & 0x01;
> > + if (val == val2) pass++;
> > + else {
> > + pass = 0;
> > + val = (ast_get_index_reg_mask(ast,
> AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
>
>
>
>
> > + }
> > + } while ((pass < 5) && (count++ < 0x10000));
> >
> > - val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10)
> >> 4;
> > return val & 1 ? 1 : 0;
> > }
> >
> > @@ -982,9 +993,20 @@ static int get_data(void *i2c_priv)
> > {
> > struct ast_i2c_chan *i2c = i2c_priv;
> > struct ast_private *ast = i2c->dev->dev_private;
> > - uint32_t val;
> > + volatile uint32_t val, val2, count, pass;
> > +
> > + count = 0;
> > + pass = 0;
> > + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7,
> 0x20) >> 5) & 0x01;
> > + do {
> > + val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT,
> 0xb7, 0x20) >> 5) & 0x01;
> > + if (val == val2) pass++;
> > + else {
> > + pass = 0;
> > + val = (ast_get_index_reg_mask(ast,
> AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
> > + }
> > + } while ((pass < 5) && (count++ < 0x10000));
> >
> > - val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20)
> >> 5;
> > return val & 1 ? 1 : 0;
> > }
> >
> > @@ -997,7 +1019,7 @@ static void set_clock(void *i2c_priv, int clock)
> >
> > for (i = 0; i < 0x10000; i++) {
> > ujcrb7 = ((clock & 0x01) ? 0 : 1);
> > - ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7,
> 0xfe, ujcrb7);
> > + ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7,
> 0xf4, ujcrb7);
> > jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT,
> 0xb7, 0x01);
> > if (ujcrb7 == jtemp)
> > break;
> > @@ -1013,7 +1035,7 @@ static void set_data(void *i2c_priv, int data)
> >
> > for (i = 0; i < 0x10000; i++) {
> > ujcrb7 = ((data & 0x01) ? 0 : 1) << 2;
> > - ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7,
> 0xfb, ujcrb7);
> > + ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7,
> 0xf1, ujcrb7);
> > jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT,
> 0xb7, 0x04);
> > if (ujcrb7 == jtemp)
> > break;
> > --
> > 1.8.3.1
> >
> > _______________________________________________
> > dri-devel mailing list
> > dri-devel@lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/dri-devel
>
[-- Attachment #1.2: Type: text/html, Size: 6117 bytes --]
[-- Attachment #2: Type: text/plain, Size: 160 bytes --]
_______________________________________________
dri-devel mailing list
dri-devel@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/dri-devel
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [[PATCH v2]] drm/ast: fixed reading monitor EDID not stable issue
2018-11-22 1:42 ` 陳雅正
@ 2018-11-22 2:48 ` Dave Airlie
0 siblings, 0 replies; 7+ messages in thread
From: Dave Airlie @ 2018-11-22 2:48 UTC (permalink / raw)
To: yacheng600221; +Cc: dri-devel, Dave Airlie, stable, Egbert Eich, Y.C. Chen
On Thu, 22 Nov 2018 at 11:42, 陳雅正 <yacheng600221@gmail.com> wrote:
>
> Hi Dave,
> Thanks for your feedback. No issue found actually if I remove "volatile" on my platform. In my experience, if the value is volatile, adding "volatile" will be safer and no harm, that is why I add it by default. If you think it is not necessary, it's ok for me to remove it.
>
Don't add it unless you've got proof you need it, we don't want it
confusing people later.
Dave.
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH v3] drm/ast: fixed reading monitor EDID not stable issue
2018-10-31 1:31 ` [[PATCH v2]] " Y.C. Chen
2018-11-22 1:15 ` Dave Airlie
@ 2018-11-22 3:56 ` Y.C. Chen
1 sibling, 0 replies; 7+ messages in thread
From: Y.C. Chen @ 2018-11-22 3:56 UTC (permalink / raw)
To: dri-devel; +Cc: airlied, eich, stable, yc_chen
From: "Y.C. Chen" <yc_chen@aspeedtech.com>
v1: over-sample data to increase the stability with some specific monitors
v2: refine to avoid infinite loop
v3: remove un-necessary "volatile" declaration
Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com>
---
drivers/gpu/drm/ast/ast_mode.c | 34 ++++++++++++++++++++++++++++------
1 file changed, 28 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 5e77d45..843e2f9 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -972,9 +972,20 @@ static int get_clock(void *i2c_priv)
{
struct ast_i2c_chan *i2c = i2c_priv;
struct ast_private *ast = i2c->dev->dev_private;
- uint32_t val;
+ uint32_t val, val2, count, pass;
+
+ count = 0;
+ pass = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ do {
+ val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ if (val == val2) pass++;
+ else {
+ pass = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01;
+ }
+ } while ((pass < 5) && (count++ < 0x10000));
- val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4;
return val & 1 ? 1 : 0;
}
@@ -982,9 +993,20 @@ static int get_data(void *i2c_priv)
{
struct ast_i2c_chan *i2c = i2c_priv;
struct ast_private *ast = i2c->dev->dev_private;
- uint32_t val;
+ uint32_t val, val2, count, pass;
+
+ count = 0;
+ pass = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ do {
+ val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ if (val == val2) pass++;
+ else {
+ pass = 0;
+ val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01;
+ }
+ } while ((pass < 5) && (count++ < 0x10000));
- val = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5;
return val & 1 ? 1 : 0;
}
@@ -997,7 +1019,7 @@ static void set_clock(void *i2c_priv, int clock)
for (i = 0; i < 0x10000; i++) {
ujcrb7 = ((clock & 0x01) ? 0 : 1);
- ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfe, ujcrb7);
+ ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf4, ujcrb7);
jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x01);
if (ujcrb7 == jtemp)
break;
@@ -1013,7 +1035,7 @@ static void set_data(void *i2c_priv, int data)
for (i = 0; i < 0x10000; i++) {
ujcrb7 = ((data & 0x01) ? 0 : 1) << 2;
- ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xfb, ujcrb7);
+ ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf1, ujcrb7);
jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x04);
if (ujcrb7 == jtemp)
break;
--
1.8.3.1
^ permalink raw reply related [flat|nested] 7+ messages in thread
end of thread, other threads:[~2018-11-22 3:56 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2018-10-30 6:00 [PATCH] drm/ast: fixed reading monitor EDID not stable issue Y.C. Chen
2018-10-30 13:01 ` Ilia Mirkin
2018-10-31 1:31 ` [[PATCH v2]] " Y.C. Chen
2018-11-22 1:15 ` Dave Airlie
2018-11-22 1:42 ` 陳雅正
2018-11-22 2:48 ` Dave Airlie
2018-11-22 3:56 ` [PATCH v3] " Y.C. Chen
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).