This is a note to let you know that I've just added the patch titled Input: mpr121 - handle multiple bits change of status register to the 3.18-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: input-mpr121-handle-multiple-bits-change-of-status-register.patch and it can be found in the queue-3.18 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Thu Nov 9 10:19:57 CET 2017 From: Akinobu Mita <akinobu.mita@xxxxxxxxx> Date: Sun, 15 Jan 2017 14:44:30 -0800 Subject: Input: mpr121 - handle multiple bits change of status register From: Akinobu Mita <akinobu.mita@xxxxxxxxx> [ Upstream commit 08fea55e37f58371bffc5336a59e55d1f155955a ] This driver reports input events on their interrupts which are triggered by the sensor's status register changes. But only single bit change is reported in the interrupt handler. So if there are multiple bits are changed at almost the same time, other press or release events are ignored. This fixes it by detecting all changed bits in the status register. Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/input/keyboard/mpr121_touchkey.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) --- a/drivers/input/keyboard/mpr121_touchkey.c +++ b/drivers/input/keyboard/mpr121_touchkey.c @@ -87,7 +87,8 @@ static irqreturn_t mpr_touchkey_interrup struct mpr121_touchkey *mpr121 = dev_id; struct i2c_client *client = mpr121->client; struct input_dev *input = mpr121->input_dev; - unsigned int key_num, key_val, pressed; + unsigned long bit_changed; + unsigned int key_num; int reg; reg = i2c_smbus_read_byte_data(client, ELE_TOUCH_STATUS_1_ADDR); @@ -105,18 +106,22 @@ static irqreturn_t mpr_touchkey_interrup reg &= TOUCH_STATUS_MASK; /* use old press bit to figure out which bit changed */ - key_num = ffs(reg ^ mpr121->statusbits) - 1; - pressed = reg & (1 << key_num); + bit_changed = reg ^ mpr121->statusbits; mpr121->statusbits = reg; + for_each_set_bit(key_num, &bit_changed, mpr121->keycount) { + unsigned int key_val, pressed; - key_val = mpr121->keycodes[key_num]; + pressed = reg & BIT(key_num); + key_val = mpr121->keycodes[key_num]; - input_event(input, EV_MSC, MSC_SCAN, key_num); - input_report_key(input, key_val, pressed); - input_sync(input); + input_event(input, EV_MSC, MSC_SCAN, key_num); + input_report_key(input, key_val, pressed); + + dev_dbg(&client->dev, "key %d %d %s\n", key_num, key_val, + pressed ? "pressed" : "released"); - dev_dbg(&client->dev, "key %d %d %s\n", key_num, key_val, - pressed ? "pressed" : "released"); + } + input_sync(input); out: return IRQ_HANDLED; Patches currently in stable-queue which might be from akinobu.mita@xxxxxxxxx are queue-3.18/input-mpr121-set-missing-event-capability.patch queue-3.18/input-mpr121-handle-multiple-bits-change-of-status-register.patch