From patchwork Wed Mar 18 22:57:27 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tony Lindgren X-Patchwork-Id: 211559 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham 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 C68E6C4332B for ; Wed, 18 Mar 2020 22:57:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9A5C92076F for ; Wed, 18 Mar 2020 22:57:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727308AbgCRW5l (ORCPT ); Wed, 18 Mar 2020 18:57:41 -0400 Received: from muru.com ([72.249.23.125]:60794 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727383AbgCRW5k (ORCPT ); Wed, 18 Mar 2020 18:57:40 -0400 Received: from hillo.muru.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTP id 753A181B1; Wed, 18 Mar 2020 22:58:25 +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 , Merlijn Wajer , Pavel Machek , ruleh , Sebastian Reichel Subject: [PATCH 3/3] Input: omap4-keypad - check state again for lost key-up interrupts Date: Wed, 18 Mar 2020 15:57:27 -0700 Message-Id: <20200318225727.29327-4-tony@atomide.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200318225727.29327-1-tony@atomide.com> References: <20200318225727.29327-1-tony@atomide.com> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org We are still missing handling for errata i689 related issues for the case where we never see a key up interrupt for the last pressed key. To fix the issue, we must scan the key state again after the keyboard controller has idled to check if a key up event was missed. This is described in the omap4 silicon errata documentation for Errata ID i689 "1.32 Keyboard Key Up Event Can Be Missed": "When a key is released for a time shorter than the debounce time, in-between 2 key press (KP1 and KP2), the keyboard state machine will go to idle mode and will never detect the key release (after KP1, and also after KP2), and thus will never generate a new IRQ indicating the key release." Let's use delayed_work after each key down event to catch stuck keys if no more interrupts are seen. We use mod_delayed_work() as we already scan for lost key up events in case of new interrupts, so only the last key down interrupt needs the delayed_work handling. Cc: Arthur Demchenkov Cc: Merlijn Wajer Cc: Pavel Machek Cc: ruleh Cc: Sebastian Reichel Signed-off-by: Tony Lindgren --- drivers/input/keyboard/omap4-keypad.c | 55 ++++++++++++++++++++++++--- 1 file changed, 49 insertions(+), 6 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 @@ -71,6 +71,8 @@ struct omap4_keypad { void __iomem *base; bool irq_wake_enabled; unsigned int irq; + struct delayed_work key_work; + struct mutex lock; /* for key scan */ unsigned int rows; unsigned int cols; @@ -154,17 +156,19 @@ static irqreturn_t omap4_keypad_irq_handler(int irq, void *dev_id) return IRQ_NONE; } -static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id) +static bool omap4_keypad_scan_keys(struct omap4_keypad *keypad_data, bool clear) { - struct omap4_keypad *keypad_data = dev_id; struct input_dev *input_dev = keypad_data->input; int keys_up, keys_down; u32 low, high; - u64 keys; + u64 keys = 0; - low = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0); - high = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32); - keys = low | (u64)high << 32; + mutex_lock(&keypad_data->lock); + if (!clear) { + low = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE31_0); + high = kbd_readl(keypad_data, OMAP4_KBD_FULLCODE63_32); + keys = low | (u64)high << 32; + } /* Scan for key up events for lost key-up interrupts */ keys_up = omap4_keypad_scan_state(keypad_data, keys, false); @@ -176,6 +180,23 @@ static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id) keypad_data->keys = keys; + mutex_unlock(&keypad_data->lock); + + return keys_down; +} + +static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id) +{ + struct omap4_keypad *keypad_data = dev_id; + bool down_events; + + down_events = omap4_keypad_scan_keys(keypad_data, false); + if (down_events) + mod_delayed_work(system_wq, &keypad_data->key_work, + msecs_to_jiffies(50)); + else + cancel_delayed_work_sync(&keypad_data->key_work); + /* clear pending interrupts */ kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS, kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS)); @@ -183,6 +204,25 @@ static irqreturn_t omap4_keypad_irq_thread_fn(int irq, void *dev_id) return IRQ_HANDLED; } +/* + * Errata ID i689 "1.32 Keyboard Key Up Event Can Be Missed". + * Interrupt may not happen for key-up events. + */ +static void omap4_keypad_work(struct work_struct *work) +{ + struct omap4_keypad *keypad_data = + container_of(work, struct omap4_keypad, key_work.work); + bool events; + u32 active; + + active = kbd_readl(keypad_data, OMAP4_KBD_STATEMACHINE); + if (active) + return; + + dev_dbg(keypad_data->input->dev.parent, "idle with events\n"); + events = omap4_keypad_scan_keys(keypad_data, true); +} + static int omap4_keypad_open(struct input_dev *input) { struct omap4_keypad *keypad_data = input_get_drvdata(input); @@ -275,6 +315,8 @@ static int omap4_keypad_probe(struct platform_device *pdev) } keypad_data->irq = irq; + mutex_init(&keypad_data->lock); + INIT_DELAYED_WORK(&keypad_data->key_work, omap4_keypad_work); error = omap4_keypad_parse_dt(&pdev->dev, keypad_data); if (error) @@ -410,6 +452,7 @@ static int omap4_keypad_remove(struct platform_device *pdev) struct resource *res; free_irq(keypad_data->irq, keypad_data); + cancel_delayed_work_sync(&keypad_data->key_work); pm_runtime_disable(&pdev->dev);