On Mon, Jul 20, 2015 at 07:19:21AM +0200, external.Oleksij.Rempel wrote: > Hi Dmitry, > > > On 17.07.2015 23:58, Dmitry Torokhov wrote: > >Hi Oleksij, > > > >On Tue, Jul 14, 2015 at 08:40:47AM +0200, external.Oleksij.Rempel wrote: > >>Hi Dmitry, > >> > >>On 13.07.2015 19:07, Dmitry Torokhov wrote: > >>>On Mon, Jul 13, 2015 at 02:49:38PM +0200, Dirk Behme wrote: > >>>>From: Oleksij Rempel <[email protected]> > >>>> > >>>>If zforce is not ready to process the interrupt, the touchscreen will > >>>>be lost forever. Make sure we enable the interrupt only if processing > >>>>is ready. > >>>> > >>>>Signed-off-by: Oleksij Rempel <[email protected]> > >>>>Signed-off-by: Dirk Behme <[email protected]> > >>>>--- > >>>> drivers/input/touchscreen/zforce_ts.c | 7 ++++++- > >>>> 1 file changed, 6 insertions(+), 1 deletion(-) > >>>> > >>>>diff --git a/drivers/input/touchscreen/zforce_ts.c > >>>>b/drivers/input/touchscreen/zforce_ts.c > >>>>index 19dc297..a1889e5 100644 > >>>>--- a/drivers/input/touchscreen/zforce_ts.c > >>>>+++ b/drivers/input/touchscreen/zforce_ts.c > >>>>@@ -22,6 +22,7 @@ > >>>> #include <linux/slab.h> > >>>> #include <linux/input.h> > >>>> #include <linux/interrupt.h> > >>>>+#include <linux/irq.h> > >>>> #include <linux/i2c.h> > >>>> #include <linux/delay.h> > >>>> #include <linux/gpio/consumer.h> > >>>>@@ -741,6 +742,7 @@ static int zforce_probe(struct i2c_client *client, > >>>> struct zforce_ts *ts; > >>>> struct input_dev *input_dev; > >>>> int ret; > >>>>+ unsigned int irq; > >>>> if (!pdata) { > >>>> pdata = zforce_parse_dt(&client->dev); > >>>>@@ -835,6 +837,7 @@ static int zforce_probe(struct i2c_client *client, > >>>> init_completion(&ts->command_done); > >>>>+ irq = client->irq; > >>>> /* > >>>> * The zforce pulls the interrupt low when it has data ready. > >>>> * After it is triggered the isr thread runs until all the > >>>> available > >>>>@@ -842,7 +845,8 @@ static int zforce_probe(struct i2c_client *client, > >>>> * Therefore we can trigger the interrupt anytime it is low and > >>>> do > >>>> * not need to limit it to the interrupt edge. > >>>> */ > >>>>- ret = devm_request_threaded_irq(&client->dev, client->irq, > >>>>+ irq_set_status_flags(irq, IRQ_NOAUTOEN); > >>>Instead of playing with the flags should we simply request irq after we > >>>release the reset pin? > >>Because we should be able to process the interrupt. If i put > >>request_irq after reset, some times the interrupt can be missed. > >OK, I see that enabling after reset is racy. But I am still confused why > >having IRQ enabled while reste pin is asserted results in lost > >touchscreen. Can you walk me through the sequence of events? > > > >Thanks. > Mostly it will fail if zforce attached over SerDes > (Serializer/Deserializer). If we register IRQ after release of reset > pin, SerDes will get irq just before it has irq handler. In this > case irq will be lost, which means, not BOOT event will be passed to > the zforce.
Yes, I agreed that requesting interrupt after releasing reset pin is not a good idea. But what is the issue with the original code that requests interrupt first (and enables it) and then releases the reset pin? Thanks. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
