From patchwork Sun Jan 10 19:05:26 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 12009377 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5846CC43381 for ; Sun, 10 Jan 2021 19:07:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3A85C22AAB for ; Sun, 10 Jan 2021 19:07:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726864AbhAJTG0 (ORCPT ); Sun, 10 Jan 2021 14:06:26 -0500 Received: from muru.com ([72.249.23.125]:42274 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726267AbhAJTGZ (ORCPT ); Sun, 10 Jan 2021 14:06:25 -0500 Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id E6BE5810A; Sun, 10 Jan 2021 19:05:43 +0000 (UTC) From: Tony Lindgren To: Dmitry Torokhov Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, Arthur Demchenkov , Carl Philipp Klemm , Merlijn Wajer , Pavel Machek , ruleh , Sebastian Reichel Subject: [PATCH 2/5] Input: omap4-keypad - scan keys in two phases and simplify with bitmask Date: Sun, 10 Jan 2021 21:05:26 +0200 Message-Id: <20210110190529.46135-3-tony@atomide.com> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210110190529.46135-1-tony@atomide.com> References: <20210110190529.46135-1-tony@atomide.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org Because of errata i689 the keyboard can idle with state where no key up interrupts are seen until after the next key press. This means we need to first check for any lost key up events before scanning for new down events. 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. Let's also simplify things with for_each_set_bit() as suggested by Dmitry Torokhov . Cc: Arthur Demchenkov Cc: Carl Philipp Klemm Cc: Merlijn Wajer Cc: Pavel Machek Cc: ruleh Cc: Sebastian Reichel Signed-off-by: Tony Lindgren --- drivers/input/keyboard/omap4-keypad.c | 69 ++++++++++++++++++--------- 1 file changed, 46 insertions(+), 23 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 @@ -78,7 +78,7 @@ struct omap4_keypad { u32 irqreg_offset; unsigned int row_shift; bool no_autorepeat; - unsigned char key_state[8]; + u64 keys; unsigned short *keymap; }; @@ -107,6 +107,41 @@ static void kbd_write_irqreg(struct omap4_keypad *keypad_data, keypad_data->base + keypad_data->irqreg_offset + offset); } +static int omap4_keypad_scan_state(struct omap4_keypad *keypad_data, u64 keys, + bool down) +{ + struct input_dev *input_dev = keypad_data->input; + unsigned int col, row, code; + DECLARE_BITMAP(mask, 64); + unsigned long bit; + int events = 0; + bool key_down; + u64 changed; + + changed = keys ^ keypad_data->keys; + bitmap_from_u64(mask, changed); + + for_each_set_bit(bit, mask, keypad_data->rows * BITS_PER_BYTE) { + row = bit / BITS_PER_BYTE; + col = bit % BITS_PER_BYTE; + code = MATRIX_SCAN_CODE(row, col, keypad_data->row_shift); + + if (BIT_ULL(bit) & keys) + key_down = true; + else + key_down = false; + + 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); + events++; + } + + return events; +} /* Interrupt handlers */ static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id) @@ -123,34 +158,22 @@ static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id) { struct omap4_keypad *keypad_data = dev_id; 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 *new_state = (u32 *) key_state; + u32 low, high; + u64 keys; - *new_state = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0); - *(new_state + 1) = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32); + low = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0); + high = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32); + keys = low | (u64)high << 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 events for lost key-up interrupts */ + omap4_keypad_scan_state(keypad_data, keys, 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, keys, true); input_sync(input_dev); - memcpy(keypad_data->key_state, key_state, - sizeof(keypad_data->key_state)); + keypad_data->keys = keys; /* clear pending interrupts */ kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,