| Message ID | 1440445048-24694-3-git-send-email-linux@rainbow-software.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 24/08/15 22:37, Ondrej Zary wrote: > i2c-algo-bit allows I2C adapters without SCL read capability to work but > fb_ddc_read fails to work on them. > > Fix fb_ddc_read to work with I2C adapters not capable of reading SCL. > > Signed-off-by: Ondrej Zary <linux@rainbow-software.org> > Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl> > --- > drivers/video/fbdev/core/fb_ddc.c | 8 +++++--- > 1 file changed, 5 insertions(+), 3 deletions(-) > > diff --git a/drivers/video/fbdev/core/fb_ddc.c b/drivers/video/fbdev/core/fb_ddc.c > index 94322cc..22c694a 100644 > --- a/drivers/video/fbdev/core/fb_ddc.c > +++ b/drivers/video/fbdev/core/fb_ddc.c > @@ -69,10 +69,11 @@ unsigned char *fb_ddc_read(struct i2c_adapter *adapter) > algo_data->setscl(algo_data->data, 1); > for (j = 0; j < 5; j++) { > msleep(10); > - if (algo_data->getscl(algo_data->data)) > + if (algo_data->getscl && > + algo_data->getscl(algo_data->data)) > break; > } > - if (j == 5) > + if (algo_data->getscl && j == 5) > continue; > > algo_data->setsda(algo_data->data, 0); > @@ -91,7 +92,8 @@ unsigned char *fb_ddc_read(struct i2c_adapter *adapter) > algo_data->setscl(algo_data->data, 1); > for (j = 0; j < 10; j++) { > msleep(10); > - if (algo_data->getscl(algo_data->data)) > + if (algo_data->getscl && > + algo_data->getscl(algo_data->data)) > break; > } Aren't both of those loops pointless if there's no getscl? Tomi
On Wednesday 02 September 2015, Tomi Valkeinen wrote: > On 24/08/15 22:37, Ondrej Zary wrote: > > i2c-algo-bit allows I2C adapters without SCL read capability to work but > > fb_ddc_read fails to work on them. > > > > Fix fb_ddc_read to work with I2C adapters not capable of reading SCL. > > > > Signed-off-by: Ondrej Zary <linux@rainbow-software.org> > > Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl> > > --- > > drivers/video/fbdev/core/fb_ddc.c | 8 +++++--- > > 1 file changed, 5 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/video/fbdev/core/fb_ddc.c > > b/drivers/video/fbdev/core/fb_ddc.c index 94322cc..22c694a 100644 > > --- a/drivers/video/fbdev/core/fb_ddc.c > > +++ b/drivers/video/fbdev/core/fb_ddc.c > > @@ -69,10 +69,11 @@ unsigned char *fb_ddc_read(struct i2c_adapter > > *adapter) algo_data->setscl(algo_data->data, 1); > > for (j = 0; j < 5; j++) { > > msleep(10); > > - if (algo_data->getscl(algo_data->data)) > > + if (algo_data->getscl && > > + algo_data->getscl(algo_data->data)) > > break; > > } > > - if (j == 5) > > + if (algo_data->getscl && j == 5) > > continue; > > > > algo_data->setsda(algo_data->data, 0); > > @@ -91,7 +92,8 @@ unsigned char *fb_ddc_read(struct i2c_adapter *adapter) > > algo_data->setscl(algo_data->data, 1); > > for (j = 0; j < 10; j++) { > > msleep(10); > > - if (algo_data->getscl(algo_data->data)) > > + if (algo_data->getscl && > > + algo_data->getscl(algo_data->data)) > > break; > > } > > Aren't both of those loops pointless if there's no getscl? They're reduced to delays - don't know how much critical they are.
On 02/09/15 15:04, Ondrej Zary wrote: > On Wednesday 02 September 2015, Tomi Valkeinen wrote: >> On 24/08/15 22:37, Ondrej Zary wrote: >>> i2c-algo-bit allows I2C adapters without SCL read capability to work but >>> fb_ddc_read fails to work on them. >>> >>> Fix fb_ddc_read to work with I2C adapters not capable of reading SCL. >>> >>> Signed-off-by: Ondrej Zary <linux@rainbow-software.org> >>> Acked-by: Krzysztof Helt <krzysztof.h1@wp.pl> >>> --- >>> drivers/video/fbdev/core/fb_ddc.c | 8 +++++--- >>> 1 file changed, 5 insertions(+), 3 deletions(-) >>> >>> diff --git a/drivers/video/fbdev/core/fb_ddc.c >>> b/drivers/video/fbdev/core/fb_ddc.c index 94322cc..22c694a 100644 >>> --- a/drivers/video/fbdev/core/fb_ddc.c >>> +++ b/drivers/video/fbdev/core/fb_ddc.c >>> @@ -69,10 +69,11 @@ unsigned char *fb_ddc_read(struct i2c_adapter >>> *adapter) algo_data->setscl(algo_data->data, 1); >>> for (j = 0; j < 5; j++) { >>> msleep(10); >>> - if (algo_data->getscl(algo_data->data)) >>> + if (algo_data->getscl && >>> + algo_data->getscl(algo_data->data)) >>> break; >>> } >>> - if (j == 5) >>> + if (algo_data->getscl && j == 5) >>> continue; >>> >>> algo_data->setsda(algo_data->data, 0); >>> @@ -91,7 +92,8 @@ unsigned char *fb_ddc_read(struct i2c_adapter *adapter) >>> algo_data->setscl(algo_data->data, 1); >>> for (j = 0; j < 10; j++) { >>> msleep(10); >>> - if (algo_data->getscl(algo_data->data)) >>> + if (algo_data->getscl && >>> + algo_data->getscl(algo_data->data)) >>> break; >>> } >> >> Aren't both of those loops pointless if there's no getscl? > > They're reduced to delays - don't know how much critical they are. I think the code gets somewhat confusing the way you did it. Maybe instead something like: if (algo_data->getscl) { the current loop & delays here; } else { msleep(25); // 25 was just a guess... } Tomi
diff --git a/drivers/video/fbdev/core/fb_ddc.c b/drivers/video/fbdev/core/fb_ddc.c index 94322cc..22c694a 100644 --- a/drivers/video/fbdev/core/fb_ddc.c +++ b/drivers/video/fbdev/core/fb_ddc.c @@ -69,10 +69,11 @@ unsigned char *fb_ddc_read(struct i2c_adapter *adapter) algo_data->setscl(algo_data->data, 1); for (j = 0; j < 5; j++) { msleep(10); - if (algo_data->getscl(algo_data->data)) + if (algo_data->getscl && + algo_data->getscl(algo_data->data)) break; } - if (j == 5) + if (algo_data->getscl && j == 5) continue; algo_data->setsda(algo_data->data, 0); @@ -91,7 +92,8 @@ unsigned char *fb_ddc_read(struct i2c_adapter *adapter) algo_data->setscl(algo_data->data, 1); for (j = 0; j < 10; j++) { msleep(10); - if (algo_data->getscl(algo_data->data)) + if (algo_data->getscl && + algo_data->getscl(algo_data->data)) break; }