diff mbox

[v2,1/2] fb_ddc: Allow I2C adapters without SCL read capability

Message ID 1443132854-31786-1-git-send-email-linux@rainbow-software.org (mailing list archive)
State New, archived
Headers show

Commit Message

Ondrej Zary Sept. 24, 2015, 10:14 p.m. UTC 
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>
---
 drivers/video/fbdev/core/fb_ddc.c |   28 ++++++++++++++++++----------
 1 file changed, 18 insertions(+), 10 deletions(-)

Comments

Tomi Valkeinen Sept. 30, 2015, 7:55 a.m. UTC | #1 
On 25/09/15 01:14, 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>
> ---
>  drivers/video/fbdev/core/fb_ddc.c |   28 ++++++++++++++++++----------
>  1 file changed, 18 insertions(+), 10 deletions(-)

Thanks, queued this and the 2/2 patch for 4.4.

 Tomi
diff mbox

Patch

diff --git a/drivers/video/fbdev/core/fb_ddc.c b/drivers/video/fbdev/core/fb_ddc.c
index 94322cc..8bf5f2f 100644
--- a/drivers/video/fbdev/core/fb_ddc.c
+++ b/drivers/video/fbdev/core/fb_ddc.c
@@ -67,13 +67,17 @@  unsigned char *fb_ddc_read(struct i2c_adapter *adapter)
 		msleep(13);
 
 		algo_data->setscl(algo_data->data, 1);
-		for (j = 0; j < 5; j++) {
-			msleep(10);
-			if (algo_data->getscl(algo_data->data))
-				break;
+		if (algo_data->getscl) {
+			for (j = 0; j < 5; j++) {
+				msleep(10);
+				if (algo_data->getscl(algo_data->data))
+					break;
+			}
+			if (j == 5)
+				continue;
+		} else {
+			udelay(algo_data->udelay);
 		}
-		if (j == 5)
-			continue;
 
 		algo_data->setsda(algo_data->data, 0);
 		msleep(15);
@@ -89,10 +93,14 @@  unsigned char *fb_ddc_read(struct i2c_adapter *adapter)
 		msleep(15);
 
 		algo_data->setscl(algo_data->data, 1);
-		for (j = 0; j < 10; j++) {
-			msleep(10);
-			if (algo_data->getscl(algo_data->data))
-				break;
+		if (algo_data->getscl) {
+			for (j = 0; j < 10; j++) {
+				msleep(10);
+				if (algo_data->getscl(algo_data->data))
+					break;
+			}
+		} else {
+			udelay(algo_data->udelay);
 		}
 
 		algo_data->setsda(algo_data->data, 1);