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.reic...@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

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