On 30/11/2020 09.01, Dmitry Torokhov wrote:
On Sun, Nov 29, 2020 at 10:13:06PM +0100, Linus Walleij wrote:
On Sun, Nov 29, 2020 at 3:53 AM Dmitry Torokhov
<dmitry.torokhov@xxxxxxxxx> wrote:
On Sat, Nov 28, 2020 at 01:37:20PM +0100, Linus Walleij wrote:
@@ -1297,8 +1297,6 @@ static int mxt_check_retrigen(struct mxt_data *data)
int val;is
struct irq_data *irqd;
- data->use_retrigen_workaround = false;
-
So this will result in data->use_retrigen_workaround staying "true" for
level interrupts, which is not needed, as with those we will never lose
an edge. So I think your patch can be reduced to simply setting
data->use_retrigen_workaround to true in mxt_probe() and leaving
mxt_check_retrigen() without any changes.
I did that first but then I realized that since there is an
errorpath in mxt_check_retrigen() and it starts by disabling
the workaround so in an error occurs in
__mxt_read_reg() it will be left disabled.
If __mxt_read_reg() fails then we will bail out and leave the device not
operable, so leaving the workaround disabled does not change anything.
But I see that I fail to account for the level-trigging
case where it should disable the workaround and
bail out so I anyway need to revise the patch.
However I wonder if it would not be better to simply call
mxt_check_retrigen() before calling mxt_acquire_irq() in mxt_probe()
instead of after.
I don't fully understand this driver, but it seems the information
whether retrigen is available only appears after talking to the
device a bit, checking firmware and "objects" available on the
device and then it may already be too late.
No, because the workaround is checked only in mxt_acquire_irq() which is
called immediately preceding the check for RETRIGEN. And since
__mxt_read_reg() is a wrapper around i2c_transfer() and does not need
IRQs to be enalbed, we can move stuff around. Could you please check if
the following works for you:
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index dde364dfb79d..2b3fff0822fe 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -2185,11 +2185,11 @@ static int mxt_initialize(struct mxt_data *data)
msleep(MXT_FW_RESET_TIME);
}
- error = mxt_acquire_irq(data);
+ error = mxt_check_retrigen(data);
if (error)
return error;
- error = mxt_check_retrigen(data);
+ error = mxt_acquire_irq(data);
if (error)
return error;
This swap also fixes the driver for me. So both Linus' and your approach work here.
The log says
[ 0.212647] atmel_mxt_ts i2c-ATML0000:01: Family: 164 Variant: 17 Firmware V1.0.AA Objects: 32
[ 0.212804] atmel_mxt_ts i2c-ATML0000:01: Enabling RETRIGEN workaround
[ 0.228469] atmel_mxt_ts i2c-ATML0000:01: Direct firmware load for maxtouch.cfg failed with error -2
[ 0.229979] atmel_mxt_ts i2c-ATML0000:01: Touchscreen size X960Y540
[ 0.230023] input: Atmel maXTouch Touchpad as /devices/pci0000:00/INT3432:00/i2c-0/i2c-ATML0000:01/input/input4
[ 0.236080] atmel_mxt_ts i2c-ATML0001:01: Family: 164 Variant: 13 Firmware V1.0.AA Objects: 41
[ 0.236478] atmel_mxt_ts i2c-ATML0001:01: Enabling RETRIGEN workaround
[ 0.256034] atmel_mxt_ts i2c-ATML0001:01: Direct firmware load for maxtouch.cfg failed with error -2
[ 0.257608] atmel_mxt_ts i2c-ATML0001:01: Touchscreen size X2559Y1699
[ 0.257642] input: Atmel maXTouch Touchscreen as /devices/pci0000:00/INT3433:00/i2c-1/i2c-ATML0001:01/input/input5
Thank you,
Andre
