From patchwork Fri Feb 28 18:02:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 11413125 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 07CB5138D for ; Fri, 28 Feb 2020 18:03:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E5303246AE for ; Fri, 28 Feb 2020 18:03:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726791AbgB1SCr (ORCPT ); Fri, 28 Feb 2020 13:02:47 -0500 Received: from muru.com ([72.249.23.125]:58278 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725730AbgB1SCr (ORCPT ); Fri, 28 Feb 2020 13:02:47 -0500 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id 5C966806C; Fri, 28 Feb 2020 18:03:31 +0000 (UTC) Date: Fri, 28 Feb 2020 10:02:43 -0800 From: Tony Lindgren To: Dmitry Torokhov Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, Arthur Demchenkov , Merlijn Wajer , Pavel Machek , Sebastian Reichel , ruleh Subject: [PATCHv2 4/3] Input: omap4-keypad - scan the keys in two phases to detect lost key-up Message-ID: <20200228180243.GM37466@atomide.com> References: <20200228171223.11444-1-tony@atomide.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200228171223.11444-1-tony@atomide.com> Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org In addition to handling errata i689 for idle with state, we must also check for lost key up interrupts on fast key presses. For example rapidly pressing shift-shift-j can sometimes produce a J instead of j. Let's fix the issue by scanning the keyboard in two phases. First we scan for any key up events that we may have missed, and then we scan for key down events. Cc: Arthur Demchenkov Cc: Merlijn Wajer Cc: Pavel Machek Cc: Sebastian Reichel Signed-off-by: Tony Lindgren --- drivers/input/keyboard/omap4-keypad.c | 48 ++++++++++++++++++--------- 1 file changed, 32 insertions(+), 16 deletions(-) diff --git a/drivers/input/keyboard/omap4-keypad.c b/drivers/input/keyboard/omap4-keypad.c --- a/drivers/input/keyboard/omap4-keypad.c +++ b/drivers/input/keyboard/omap4-keypad.c @@ -109,6 +109,34 @@ static void kbd_write_irqreg(struct omap4_keypad *keypad_data, keypad_data->base + keypad_data->irqreg_offset + offset); } +static void omap4_keypad_scan_state(struct omap4_keypad *keypad_data, + unsigned char *key_state, + bool down) +{ + struct input_dev *input_dev = keypad_data->input; + unsigned int col, row, code, changed; + bool key_down; + + for (row = 0; row < keypad_data->rows; row++) { + changed = key_state[row] ^ keypad_data->key_state[row]; + if (!changed) + continue; + + for (col = 0; col < keypad_data->cols; col++) { + if (changed & (1 << col)) { + code = MATRIX_SCAN_CODE(row, col, + keypad_data->row_shift); + key_down = key_state[row] & (1 << col); + if (key_down != down) + continue; + input_event(input_dev, EV_MSC, MSC_SCAN, code); + input_report_key(input_dev, + keypad_data->keymap[code], + key_down); + } + } + } +} /* Interrupt handlers */ static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id) @@ -125,7 +153,6 @@ static bool omap4_keypad_scan_keys(struct omap4_keypad *keypad_data, bool clear) { struct input_dev *input_dev = keypad_data->input; unsigned char key_state[ARRAY_SIZE(keypad_data->key_state)]; - unsigned int col, row, code, changed; u32 *rows_lo = (u32 *)key_state; u32 *rows_hi = rows_lo + 1; @@ -138,22 +165,11 @@ static bool omap4_keypad_scan_keys(struct omap4_keypad *keypad_data, bool clear) *rows_hi = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32); } - for (row = 0; row < keypad_data->rows; row++) { - changed = key_state[row] ^ keypad_data->key_state[row]; - if (!changed) - continue; + /* Scan for key up evetns for lost key-up interrupts */ + omap4_keypad_scan_state(keypad_data, key_state, false); - for (col = 0; col < keypad_data->cols; col++) { - if (changed & (1 << col)) { - code = MATRIX_SCAN_CODE(row, col, - keypad_data->row_shift); - input_event(input_dev, EV_MSC, MSC_SCAN, code); - input_report_key(input_dev, - keypad_data->keymap[code], - key_state[row] & (1 << col)); - } - } - } + /* Scan for key down events */ + omap4_keypad_scan_state(keypad_data, key_state, true); input_sync(input_dev);