From ca1cd36cef00260db6b35b32d863e0c580c0488d Mon Sep 17 00:00:00 2001 From: Sebastian Reichel Date: Thu, 24 May 2018 09:33:36 -0700 Subject: [PATCH] Input: atmel_mxt_ts - fix reset-gpio for level based irqs 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 Reviewed-by: Pavel Machek Signed-off-by: Dmitry Torokhov --- 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 4ac49c6c0006..54fe190fd4bc 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 */ @@ -1208,7 +1210,7 @@ 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); @@ -3082,20 +3084,14 @@ 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; -- 2.30.2