* [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
@ 2018-04-20 17:24 Sebastian Reichel
2018-04-20 17:44 ` Ezequiel Garcia
2018-04-23 11:58 ` [PATCHv2] " Sebastian Reichel
0 siblings, 2 replies; 10+ messages in thread
From: Sebastian Reichel @ 2018-04-20 17:24 UTC (permalink / raw)
To: Nick Dyer, Dmitry Torokhov, linux-input
Cc: linux-kernel, kernel, Sebastian Reichel
The current reset-gpio support triggers an interrupt storm on platforms
using the maxtouch with level based interrupt. The Motorola Droid 4,
which I used for some of the tests is not affected, since it uses a level
based interrupt.
This change avoids the interrupt storm by enabling the device while
its interrupt is disabled. The following mxt_initialize() requires,
that the device is responsive (at least mxt224E is unresponsive for
~22ms), so we wait some time. We don't wait for leaving bootloader
mode anymore, since mxt_initialize() checks for it anyways.
This fixes a boot problem on GE PPD (watchdog kills device) and also
has been tested on the Droid 4.
Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line")
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
---
drivers/input/touchscreen/atmel_mxt_ts.c | 15 +++++----------
1 file changed, 5 insertions(+), 10 deletions(-)
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 5d9699fe1b55..f8a9f2a47e78 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -194,6 +194,7 @@ enum t100_type {
/* Delay times */
#define MXT_BACKUP_TIME 50 /* msec */
+#define MXT_RESET_GPIO_TIME 20 /* msec */
#define MXT_RESET_TIME 200 /* msec */
#define MXT_RESET_TIMEOUT 3000 /* msec */
#define MXT_CRC_TIMEOUT 1000 /* msec */
@@ -3167,20 +3168,14 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
return error;
}
+ disable_irq(client->irq);
+
if (data->reset_gpio) {
- data->in_bootloader = true;
- msleep(MXT_RESET_TIME);
- reinit_completion(&data->bl_completion);
+ msleep(MXT_RESET_GPIO_TIME);
gpiod_set_value(data->reset_gpio, 1);
- error = mxt_wait_for_completion(data, &data->bl_completion,
- MXT_RESET_TIMEOUT);
- if (error)
- return error;
- data->in_bootloader = false;
+ msleep(MXT_RESET_TIME);
}
- disable_irq(client->irq);
-
error = mxt_initialize(data);
if (error)
return error;
--
2.17.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-04-20 17:24 [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs Sebastian Reichel
@ 2018-04-20 17:44 ` Ezequiel Garcia
2018-04-20 19:42 ` Sebastian Reichel
2018-04-23 11:58 ` [PATCHv2] " Sebastian Reichel
1 sibling, 1 reply; 10+ messages in thread
From: Ezequiel Garcia @ 2018-04-20 17:44 UTC (permalink / raw)
To: Sebastian Reichel, Nick Dyer, Dmitry Torokhov, linux-input
Cc: linux-kernel, kernel
Hi Sebastian,
On Fri, 2018-04-20 at 19:24 +0200, Sebastian Reichel wrote:
> The current reset-gpio support triggers an interrupt storm on platforms
> using the maxtouch with level based interrupt. The Motorola Droid 4,
> which I used for some of the tests is not affected, since it uses a level
> based interrupt.
>
I found this confusing. Interrupt storm happen with level-based interrupts,
but the Droid4 is not affected?
> This change avoids the interrupt storm by enabling the device while
> its interrupt is disabled. The following mxt_initialize() requires,
> that the device is responsive (at least mxt224E is unresponsive for
> ~22ms), so we wait some time. We don't wait for leaving bootloader
> mode anymore, since mxt_initialize() checks for it anyways.
>
IMHO, having some more or less arbritrary sleeps is almost
always a problem. This value might be enough for some platform,
might be too short for some other, and then it might get too large
for someone else.
> This fixes a boot problem on GE PPD (watchdog kills device) and also
> has been tested on the Droid 4.
>
> Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line")
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
> ---
> drivers/input/touchscreen/atmel_mxt_ts.c | 15 +++++----------
> 1 file changed, 5 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> index 5d9699fe1b55..f8a9f2a47e78 100644
> --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> @@ -194,6 +194,7 @@ enum t100_type {
>
> /* Delay times */
> #define MXT_BACKUP_TIME 50 /* msec */
> +#define MXT_RESET_GPIO_TIME 20 /* msec */
> #define MXT_RESET_TIME 200 /* msec */
> #define MXT_RESET_TIMEOUT 3000 /* msec */
> #define MXT_CRC_TIMEOUT 1000 /* msec */
> @@ -3167,20 +3168,14 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
> return error;
> }
>
> + disable_irq(client->irq);
> +
> if (data->reset_gpio) {
> - data->in_bootloader = true;
> - msleep(MXT_RESET_TIME);
> - reinit_completion(&data->bl_completion);
> + msleep(MXT_RESET_GPIO_TIME);
> gpiod_set_value(data->reset_gpio, 1);
Can't we enable the IRQ here, just before the wait...
> - error = mxt_wait_for_completion(data, &data->bl_completion,
> - MXT_RESET_TIMEOUT);
... and then disable it back afterwards?
> - if (error)
> - return error;
> - data->in_bootloader = false;
> + msleep(MXT_RESET_TIME);
> }
>
> - disable_irq(client->irq);
> -
> error = mxt_initialize(data);
> if (error)
> return error;
> --
> 2.17.0
>
>
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-04-20 17:44 ` Ezequiel Garcia
@ 2018-04-20 19:42 ` Sebastian Reichel
2018-04-21 20:11 ` Nick Dyer
0 siblings, 1 reply; 10+ messages in thread
From: Sebastian Reichel @ 2018-04-20 19:42 UTC (permalink / raw)
To: Ezequiel Garcia
Cc: Nick Dyer, Dmitry Torokhov, linux-input, linux-kernel, kernel
[-- Attachment #1: Type: text/plain, Size: 3719 bytes --]
On Fri, Apr 20, 2018 at 02:44:02PM -0300, Ezequiel Garcia wrote:
> Hi Sebastian,
>
> On Fri, 2018-04-20 at 19:24 +0200, Sebastian Reichel wrote:
> > The current reset-gpio support triggers an interrupt storm on platforms
> > using the maxtouch with level based interrupt. The Motorola Droid 4,
> > which I used for some of the tests is not affected, since it uses a level
> > based interrupt.
> >
>
> I found this confusing. Interrupt storm happen with level-based interrupts,
> but the Droid4 is not affected?
This is a typo. Droid 4 has an edge based interrupt defined, PPD has
an level based interrupt defined. PPD got an interrupt storm, Droid 4
did not.
> > This change avoids the interrupt storm by enabling the device while
> > its interrupt is disabled. The following mxt_initialize() requires,
> > that the device is responsive (at least mxt224E is unresponsive for
> > ~22ms), so we wait some time. We don't wait for leaving bootloader
> > mode anymore, since mxt_initialize() checks for it anyways.
> >
>
> IMHO, having some more or less arbritrary sleeps is almost
> always a problem. This value might be enough for some platform,
> might be too short for some other, and then it might get too large
> for someone else.
The 22ms chip-being-unresponsive are not newly introduced. The
same 22ms are also required for soft-reset. I did introduce a
new time (MXT_RESET_GPIO_TIME) for the "chip being reset" state,
since my randomly chosen 200ms from before were exaggerated
considering all mxt datasheets I checked stated only a few nano
seconds.
> > This fixes a boot problem on GE PPD (watchdog kills device) and also
> > has been tested on the Droid 4.
> >
> > Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line")
> > Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
> > ---
> > drivers/input/touchscreen/atmel_mxt_ts.c | 15 +++++----------
> > 1 file changed, 5 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> > index 5d9699fe1b55..f8a9f2a47e78 100644
> > --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> > +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> > @@ -194,6 +194,7 @@ enum t100_type {
> >
> > /* Delay times */
> > #define MXT_BACKUP_TIME 50 /* msec */
> > +#define MXT_RESET_GPIO_TIME 20 /* msec */
> > #define MXT_RESET_TIME 200 /* msec */
> > #define MXT_RESET_TIMEOUT 3000 /* msec */
> > #define MXT_CRC_TIMEOUT 1000 /* msec */
> > @@ -3167,20 +3168,14 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
> > return error;
> > }
> >
> > + disable_irq(client->irq);
> > +
> > if (data->reset_gpio) {
> > - data->in_bootloader = true;
> > - msleep(MXT_RESET_TIME);
> > - reinit_completion(&data->bl_completion);
> > + msleep(MXT_RESET_GPIO_TIME);
> > gpiod_set_value(data->reset_gpio, 1);
>
> Can't we enable the IRQ here, just before the wait...
>
> > - error = mxt_wait_for_completion(data, &data->bl_completion,
> > - MXT_RESET_TIMEOUT);
>
> ... and then disable it back afterwards?
Yes and no. We need the wait, since the interrupt pin does random
stuff for 100ms after reset. We can do the wait-for-completion
after that time (see mxt_soft_reset function). I kept it simple,
since the following init does another soft reset anyways.
> > - if (error)
> > - return error;
> > - data->in_bootloader = false;
> > + msleep(MXT_RESET_TIME);
>
> > }
> >
> > - disable_irq(client->irq);
> > -
> > error = mxt_initialize(data);
> > if (error)
> > return error;
-- Sebastian
[-- Attachment #2: signature.asc --]
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-04-20 19:42 ` Sebastian Reichel
@ 2018-04-21 20:11 ` Nick Dyer
2018-04-23 11:43 ` Sebastian Reichel
0 siblings, 1 reply; 10+ messages in thread
From: Nick Dyer @ 2018-04-21 20:11 UTC (permalink / raw)
To: Sebastian Reichel, Ezequiel Garcia
Cc: Dmitry Torokhov, linux-input, linux-kernel, kernel
On Fri, Apr 20, 2018 at 09:42:07PM +0200, Sebastian Reichel wrote:
> On Fri, Apr 20, 2018 at 02:44:02PM -0300, Ezequiel Garcia wrote:
> > Hi Sebastian,
> >
> > On Fri, 2018-04-20 at 19:24 +0200, Sebastian Reichel wrote:
> > > The current reset-gpio support triggers an interrupt storm on platforms
> > > using the maxtouch with level based interrupt. The Motorola Droid 4,
> > > which I used for some of the tests is not affected, since it uses a level
> > > based interrupt.
> > >
> >
> > I found this confusing. Interrupt storm happen with level-based interrupts,
> > but the Droid4 is not affected?
Can I ask what happens during the interrupt storm. Are you getting lots
of the "failed to read T44 and T5" message, or something else?
> > > This change avoids the interrupt storm by enabling the device while
> > > its interrupt is disabled. The following mxt_initialize() requires,
> > > that the device is responsive (at least mxt224E is unresponsive for
> > > ~22ms), so we wait some time. We don't wait for leaving bootloader
> > > mode anymore, since mxt_initialize() checks for it anyways.
> > >
> >
> > IMHO, having some more or less arbritrary sleeps is almost
> > always a problem. This value might be enough for some platform,
> > might be too short for some other, and then it might get too large
> > for someone else.
>
> The 22ms chip-being-unresponsive are not newly introduced. The
> same 22ms are also required for soft-reset. I did introduce a
> new time (MXT_RESET_GPIO_TIME) for the "chip being reset" state,
> since my randomly chosen 200ms from before were exaggerated
> considering all mxt datasheets I checked stated only a few nano
> seconds.
According to the data sheets there is a period after a reset where the
CHG line is temporarily set as an input, during which the host should
ignore it. If you don't, you might get a stray interrupt and try and
communicate with the device, which might leave it in a bad state. I
think you mentioned that later in your email.
The reset time varies per chip, but the 100ms in mxt_soft_reset() was
based on discussions with app support at Atmel, so should be correct in
most cases.
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-04-21 20:11 ` Nick Dyer
@ 2018-04-23 11:43 ` Sebastian Reichel
0 siblings, 0 replies; 10+ messages in thread
From: Sebastian Reichel @ 2018-04-23 11:43 UTC (permalink / raw)
To: Nick Dyer
Cc: Ezequiel Garcia, Dmitry Torokhov, linux-input, linux-kernel, kernel
[-- Attachment #1: Type: text/plain, Size: 2784 bytes --]
Hi,
On Sat, Apr 21, 2018 at 09:11:37PM +0100, Nick Dyer wrote:
> On Fri, Apr 20, 2018 at 09:42:07PM +0200, Sebastian Reichel wrote:
> > On Fri, Apr 20, 2018 at 02:44:02PM -0300, Ezequiel Garcia wrote:
> > > Hi Sebastian,
> > >
> > > On Fri, 2018-04-20 at 19:24 +0200, Sebastian Reichel wrote:
> > > > The current reset-gpio support triggers an interrupt storm on platforms
> > > > using the maxtouch with level based interrupt. The Motorola Droid 4,
> > > > which I used for some of the tests is not affected, since it uses a level
> > > > based interrupt.
> > > >
> > >
> > > I found this confusing. Interrupt storm happen with level-based interrupts,
> > > but the Droid4 is not affected?
>
> Can I ask what happens during the interrupt storm. Are you getting lots
> of the "failed to read T44 and T5" message, or something else?
I don't get any message (with DEBUG enabled for the driver).
The boot process hangs and after a few seconds the watchdog kicks in.
> > > > This change avoids the interrupt storm by enabling the device while
> > > > its interrupt is disabled. The following mxt_initialize() requires,
> > > > that the device is responsive (at least mxt224E is unresponsive for
> > > > ~22ms), so we wait some time. We don't wait for leaving bootloader
> > > > mode anymore, since mxt_initialize() checks for it anyways.
> > > >
> > >
> > > IMHO, having some more or less arbritrary sleeps is almost
> > > always a problem. This value might be enough for some platform,
> > > might be too short for some other, and then it might get too large
> > > for someone else.
> >
> > The 22ms chip-being-unresponsive are not newly introduced. The
> > same 22ms are also required for soft-reset. I did introduce a
> > new time (MXT_RESET_GPIO_TIME) for the "chip being reset" state,
> > since my randomly chosen 200ms from before were exaggerated
> > considering all mxt datasheets I checked stated only a few nano
> > seconds.
>
> According to the data sheets there is a period after a reset where the
> CHG line is temporarily set as an input, during which the host should
> ignore it. If you don't, you might get a stray interrupt and try and
> communicate with the device, which might leave it in a bad state. I
> think you mentioned that later in your email.
>
> The reset time varies per chip, but the 100ms in mxt_soft_reset() was
> based on discussions with app support at Atmel, so should be correct in
> most cases.
Right. This sleep time is missing for the gpio based reset. The
other checks are not required, since the chip initialization
routine is called directly afterwards. I will send a PATCHv2,
that fixes the patch description and uses the same timeout value
for both resets.
-- Sebastian
[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]
^ permalink raw reply [flat|nested] 10+ messages in thread
* [PATCHv2] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-04-20 17:24 [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs Sebastian Reichel
2018-04-20 17:44 ` Ezequiel Garcia
@ 2018-04-23 11:58 ` Sebastian Reichel
2018-05-03 9:15 ` Sebastian Reichel
` (2 more replies)
1 sibling, 3 replies; 10+ messages in thread
From: Sebastian Reichel @ 2018-04-23 11:58 UTC (permalink / raw)
To: Nick Dyer, Dmitry Torokhov, linux-input
Cc: linux-kernel, Ezequiel Garcia, kernel, Sebastian Reichel
The current reset-gpio support triggers an interrupt storm on platforms
using the maxtouch with level based interrupt. The Motorola Droid 4,
which I used for some of the tests is not affected, since it uses a edge
based interrupt.
This change avoids the interrupt storm by enabling the device while its
interrupt is disabled. Afterwards we wait 100ms. This is important for
two reasons: The device is unresponsive for some time (~22ms for
mxt224E) and the CHG (interrupt) line is not working properly for 100ms.
We don't need to wait for any following interrupts, since the following
mxt_initialize() checks for bootloader mode anyways.
This fixes a boot issue on GE PPD (watchdog kills device due to
interrupt storm) and does not cause regression on Motorola Droid 4.
Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line")
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
---
Changes since PATCHv2:
* fix patch description
* use same timeout value for soft and gpio-reset
---
drivers/input/touchscreen/atmel_mxt_ts.c | 18 +++++++-----------
1 file changed, 7 insertions(+), 11 deletions(-)
diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
index 5d9699fe1b55..f97fbb0af020 100644
--- a/drivers/input/touchscreen/atmel_mxt_ts.c
+++ b/drivers/input/touchscreen/atmel_mxt_ts.c
@@ -194,6 +194,8 @@ enum t100_type {
/* Delay times */
#define MXT_BACKUP_TIME 50 /* msec */
+#define MXT_RESET_GPIO_TIME 20 /* msec */
+#define MXT_RESET_INVALID_CHG 100 /* msec */
#define MXT_RESET_TIME 200 /* msec */
#define MXT_RESET_TIMEOUT 3000 /* msec */
#define MXT_CRC_TIMEOUT 1000 /* msec */
@@ -1206,7 +1208,7 @@ static int mxt_soft_reset(struct mxt_data *data)
return ret;
/* Ignore CHG line for 100ms after reset */
- msleep(100);
+ msleep(MXT_RESET_INVALID_CHG);
mxt_acquire_irq(data);
@@ -3167,20 +3169,14 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
return error;
}
+ disable_irq(client->irq);
+
if (data->reset_gpio) {
- data->in_bootloader = true;
- msleep(MXT_RESET_TIME);
- reinit_completion(&data->bl_completion);
+ msleep(MXT_RESET_GPIO_TIME);
gpiod_set_value(data->reset_gpio, 1);
- error = mxt_wait_for_completion(data, &data->bl_completion,
- MXT_RESET_TIMEOUT);
- if (error)
- return error;
- data->in_bootloader = false;
+ msleep(MXT_RESET_INVALID_CHG);
}
- disable_irq(client->irq);
-
error = mxt_initialize(data);
if (error)
return error;
--
2.17.0
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCHv2] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-04-23 11:58 ` [PATCHv2] " Sebastian Reichel
@ 2018-05-03 9:15 ` Sebastian Reichel
2018-05-09 14:25 ` Pavel Machek
2018-05-24 16:35 ` Dmitry Torokhov
2 siblings, 0 replies; 10+ messages in thread
From: Sebastian Reichel @ 2018-05-03 9:15 UTC (permalink / raw)
To: Nick Dyer, Dmitry Torokhov, linux-input
Cc: linux-kernel, Ezequiel Garcia, kernel
[-- Attachment #1: Type: text/plain, Size: 2874 bytes --]
Hi,
On Mon, Apr 23, 2018 at 01:58:44PM +0200, Sebastian Reichel wrote:
> The current reset-gpio support triggers an interrupt storm on platforms
> using the maxtouch with level based interrupt. The Motorola Droid 4,
> which I used for some of the tests is not affected, since it uses a edge
> based interrupt.
>
> This change avoids the interrupt storm by enabling the device while its
> interrupt is disabled. Afterwards we wait 100ms. This is important for
> two reasons: The device is unresponsive for some time (~22ms for
> mxt224E) and the CHG (interrupt) line is not working properly for 100ms.
> We don't need to wait for any following interrupts, since the following
> mxt_initialize() checks for bootloader mode anyways.
>
> This fixes a boot issue on GE PPD (watchdog kills device due to
> interrupt storm) and does not cause regression on Motorola Droid 4.
>
> Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line")
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
> ---
> Changes since PATCHv2:
> * fix patch description
> * use same timeout value for soft and gpio-reset
> ---
ping.
-- Sebastian
> drivers/input/touchscreen/atmel_mxt_ts.c | 18 +++++++-----------
> 1 file changed, 7 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> index 5d9699fe1b55..f97fbb0af020 100644
> --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> @@ -194,6 +194,8 @@ enum t100_type {
>
> /* Delay times */
> #define MXT_BACKUP_TIME 50 /* msec */
> +#define MXT_RESET_GPIO_TIME 20 /* msec */
> +#define MXT_RESET_INVALID_CHG 100 /* msec */
> #define MXT_RESET_TIME 200 /* msec */
> #define MXT_RESET_TIMEOUT 3000 /* msec */
> #define MXT_CRC_TIMEOUT 1000 /* msec */
> @@ -1206,7 +1208,7 @@ static int mxt_soft_reset(struct mxt_data *data)
> return ret;
>
> /* Ignore CHG line for 100ms after reset */
> - msleep(100);
> + msleep(MXT_RESET_INVALID_CHG);
>
> mxt_acquire_irq(data);
>
> @@ -3167,20 +3169,14 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
> return error;
> }
>
> + disable_irq(client->irq);
> +
> if (data->reset_gpio) {
> - data->in_bootloader = true;
> - msleep(MXT_RESET_TIME);
> - reinit_completion(&data->bl_completion);
> + msleep(MXT_RESET_GPIO_TIME);
> gpiod_set_value(data->reset_gpio, 1);
> - error = mxt_wait_for_completion(data, &data->bl_completion,
> - MXT_RESET_TIMEOUT);
> - if (error)
> - return error;
> - data->in_bootloader = false;
> + msleep(MXT_RESET_INVALID_CHG);
> }
>
> - disable_irq(client->irq);
> -
> error = mxt_initialize(data);
> if (error)
> return error;
> --
> 2.17.0
>
[-- Attachment #2: signature.asc --]
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCHv2] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-04-23 11:58 ` [PATCHv2] " Sebastian Reichel
2018-05-03 9:15 ` Sebastian Reichel
@ 2018-05-09 14:25 ` Pavel Machek
2018-05-09 14:40 ` Sebastian Reichel
2018-05-24 16:35 ` Dmitry Torokhov
2 siblings, 1 reply; 10+ messages in thread
From: Pavel Machek @ 2018-05-09 14:25 UTC (permalink / raw)
To: Sebastian Reichel
Cc: Nick Dyer, Dmitry Torokhov, linux-input, linux-kernel,
Ezequiel Garcia, kernel
[-- Attachment #1: Type: text/plain, Size: 1241 bytes --]
On Mon 2018-04-23 13:58:44, Sebastian Reichel wrote:
> The current reset-gpio support triggers an interrupt storm on platforms
> using the maxtouch with level based interrupt. The Motorola Droid 4,
> which I used for some of the tests is not affected, since it uses a edge
> based interrupt.
>
> This change avoids the interrupt storm by enabling the device while its
> interrupt is disabled. Afterwards we wait 100ms. This is important for
> two reasons: The device is unresponsive for some time (~22ms for
> mxt224E) and the CHG (interrupt) line is not working properly for 100ms.
> We don't need to wait for any following interrupts, since the following
> mxt_initialize() checks for bootloader mode anyways.
>
> This fixes a boot issue on GE PPD (watchdog kills device due to
> interrupt storm) and does not cause regression on Motorola Droid 4.
Out of curiosity, what is "GE PPD"?
> Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line")
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCHv2] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-05-09 14:25 ` Pavel Machek
@ 2018-05-09 14:40 ` Sebastian Reichel
0 siblings, 0 replies; 10+ messages in thread
From: Sebastian Reichel @ 2018-05-09 14:40 UTC (permalink / raw)
To: Pavel Machek
Cc: Nick Dyer, Dmitry Torokhov, linux-input, linux-kernel,
Ezequiel Garcia, kernel
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Hi,
On Wed, May 09, 2018 at 04:25:45PM +0200, Pavel Machek wrote:
> On Mon 2018-04-23 13:58:44, Sebastian Reichel wrote:
> > The current reset-gpio support triggers an interrupt storm on platforms
> > using the maxtouch with level based interrupt. The Motorola Droid 4,
> > which I used for some of the tests is not affected, since it uses a edge
> > based interrupt.
> >
> > This change avoids the interrupt storm by enabling the device while its
> > interrupt is disabled. Afterwards we wait 100ms. This is important for
> > two reasons: The device is unresponsive for some time (~22ms for
> > mxt224E) and the CHG (interrupt) line is not working properly for 100ms.
> > We don't need to wait for any following interrupts, since the following
> > mxt_initialize() checks for bootloader mode anyways.
> >
> > This fixes a boot issue on GE PPD (watchdog kills device due to
> > interrupt storm) and does not cause regression on Motorola Droid 4.
>
> Out of curiosity, what is "GE PPD"?
PPD is a product from GE Healthcare to monitor vital biometric signals:
arch/arm/boot/dts/imx53-ppd.dts
> > Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line")
> > Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
>
> Reviewed-by: Pavel Machek <pavel@ucw.cz>
Thanks,
-- Sebastian
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^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCHv2] Input: atmel_mxt_ts - fix reset-gpio for level based irqs
2018-04-23 11:58 ` [PATCHv2] " Sebastian Reichel
2018-05-03 9:15 ` Sebastian Reichel
2018-05-09 14:25 ` Pavel Machek
@ 2018-05-24 16:35 ` Dmitry Torokhov
2 siblings, 0 replies; 10+ messages in thread
From: Dmitry Torokhov @ 2018-05-24 16:35 UTC (permalink / raw)
To: Sebastian Reichel
Cc: Nick Dyer, linux-input, linux-kernel, Ezequiel Garcia, kernel
On Mon, Apr 23, 2018 at 01:58:44PM +0200, Sebastian Reichel wrote:
> The current reset-gpio support triggers an interrupt storm on platforms
> using the maxtouch with level based interrupt. The Motorola Droid 4,
> which I used for some of the tests is not affected, since it uses a edge
> based interrupt.
>
> This change avoids the interrupt storm by enabling the device while its
> interrupt is disabled. Afterwards we wait 100ms. This is important for
> two reasons: The device is unresponsive for some time (~22ms for
> mxt224E) and the CHG (interrupt) line is not working properly for 100ms.
> We don't need to wait for any following interrupts, since the following
> mxt_initialize() checks for bootloader mode anyways.
>
> This fixes a boot issue on GE PPD (watchdog kills device due to
> interrupt storm) and does not cause regression on Motorola Droid 4.
>
> Fixes: f657b00df22e ("Input: atmel_mxt_ts - add support for reset line")
> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Applied, thank you.
> ---
> Changes since PATCHv2:
> * fix patch description
> * use same timeout value for soft and gpio-reset
> ---
> drivers/input/touchscreen/atmel_mxt_ts.c | 18 +++++++-----------
> 1 file changed, 7 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c
> index 5d9699fe1b55..f97fbb0af020 100644
> --- a/drivers/input/touchscreen/atmel_mxt_ts.c
> +++ b/drivers/input/touchscreen/atmel_mxt_ts.c
> @@ -194,6 +194,8 @@ enum t100_type {
>
> /* Delay times */
> #define MXT_BACKUP_TIME 50 /* msec */
> +#define MXT_RESET_GPIO_TIME 20 /* msec */
> +#define MXT_RESET_INVALID_CHG 100 /* msec */
> #define MXT_RESET_TIME 200 /* msec */
> #define MXT_RESET_TIMEOUT 3000 /* msec */
> #define MXT_CRC_TIMEOUT 1000 /* msec */
> @@ -1206,7 +1208,7 @@ static int mxt_soft_reset(struct mxt_data *data)
> return ret;
>
> /* Ignore CHG line for 100ms after reset */
> - msleep(100);
> + msleep(MXT_RESET_INVALID_CHG);
>
> mxt_acquire_irq(data);
>
> @@ -3167,20 +3169,14 @@ static int mxt_probe(struct i2c_client *client, const struct i2c_device_id *id)
> return error;
> }
>
> + disable_irq(client->irq);
> +
> if (data->reset_gpio) {
> - data->in_bootloader = true;
> - msleep(MXT_RESET_TIME);
> - reinit_completion(&data->bl_completion);
> + msleep(MXT_RESET_GPIO_TIME);
> gpiod_set_value(data->reset_gpio, 1);
> - error = mxt_wait_for_completion(data, &data->bl_completion,
> - MXT_RESET_TIMEOUT);
> - if (error)
> - return error;
> - data->in_bootloader = false;
> + msleep(MXT_RESET_INVALID_CHG);
> }
>
> - disable_irq(client->irq);
> -
> error = mxt_initialize(data);
> if (error)
> return error;
> --
> 2.17.0
>
--
Dmitry
^ permalink raw reply [flat|nested] 10+ messages in thread
end of thread, other threads:[~2018-05-24 16:35 UTC | newest]
Thread overview: 10+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-04-20 17:24 [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs Sebastian Reichel
2018-04-20 17:44 ` Ezequiel Garcia
2018-04-20 19:42 ` Sebastian Reichel
2018-04-21 20:11 ` Nick Dyer
2018-04-23 11:43 ` Sebastian Reichel
2018-04-23 11:58 ` [PATCHv2] " Sebastian Reichel
2018-05-03 9:15 ` Sebastian Reichel
2018-05-09 14:25 ` Pavel Machek
2018-05-09 14:40 ` Sebastian Reichel
2018-05-24 16:35 ` Dmitry Torokhov
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