From patchwork Mon Jul 29 16:33:58 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathieu Poirier X-Patchwork-Id: 2835051 Return-Path: X-Original-To: patchwork-linux-input@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id EC3269F4D4 for ; Mon, 29 Jul 2013 16:34:16 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1976C202DD for ; Mon, 29 Jul 2013 16:34:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BD3AD202B8 for ; Mon, 29 Jul 2013 16:34:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757114Ab3G2QeJ (ORCPT ); Mon, 29 Jul 2013 12:34:09 -0400 Received: from mail-pa0-f43.google.com ([209.85.220.43]:56658 "EHLO mail-pa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755508Ab3G2QeI (ORCPT ); Mon, 29 Jul 2013 12:34:08 -0400 Received: by mail-pa0-f43.google.com with SMTP id hz10so5041605pad.30 for ; Mon, 29 Jul 2013 09:34:07 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:x-gm-message-state; bh=Saq7+LBBbUTgYihA1cwG1djTpzciYUuZmXiPmmgNwwA=; b=YGEYkprNtQyH3kY9XaEdgMb1DD1ojd2AI4BfCwzWtYwKL/LdBsxLm2tS7MlAuqL6rB TrKCmtcycOyeki8bJboIR9oOcVnHKaZSwo0jhdhw0GpPHdGVhZi7ldyv03EZF+K/7Ins fQtssTcF7jISCEaEhdUHnHrWORy/E9sVqFi9I9c80hAP7RwyXs487P+dc/UBV+TXo1qy oSBTmJFvzRWigybXMUUEqjIO4pEbdhcHhi2jzIZ9YlQqiid0+lieKvdkGbcTHVMdyH/V n8tuLppovytb6iV0PbRFbwbjTOgdT3dFgey6tN+OW2uKxb4GvWGSVWgPoHpk5/5EqDb6 97jQ== X-Received: by 10.68.195.35 with SMTP id ib3mr68403556pbc.53.1375115647295; Mon, 29 Jul 2013 09:34:07 -0700 (PDT) Received: from t430.cg.shawcable.net (S0106002369de4dac.cg.shawcable.net. [70.73.24.112]) by mx.google.com with ESMTPSA id qh10sm37931879pbb.33.2013.07.29.09.34.05 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 29 Jul 2013 09:34:06 -0700 (PDT) From: mathieu.poirier@linaro.org To: robherring2@gmail.com, grant.likely@linaro.org, dmitry.torokhov@gmail.com Cc: devicetree@vger.kernel.org, john.stultz@linaro.org, linux-input@vger.kernel.org, kernel-team@android.com, mathieu.poirier@linaro.org Subject: [PATCH v6] Input: sysrq - DT binding for key sequence Date: Mon, 29 Jul 2013 10:33:58 -0600 Message-Id: <1375115638-21236-1-git-send-email-mathieu.poirier@linaro.org> X-Mailer: git-send-email 1.8.1.2 X-Gm-Message-State: ALoCoQlA0WCVhjn8VptL4bbWD0t/kJC7Lcl/bep2K72oWp6/ExiWIosamkjdqJ5G1sLiCkglwZgM Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org X-Spam-Status: No, score=-8.4 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: "Mathieu J. Poirier" Adding a simple device tree binding for the specification of key sequences. Definition of the keys found in the sequence are located in 'include/uapi/linux/input.h'. For the sysrq driver, holding the sequence of keys down for a specific amount of time will reset the system. Signed-off-by: Mathieu Poirier Acked-by: Grant Likely --- changes for v6: - Made binding description more specific. 'sysrq-reset-seq's definition was enhanced and the case where 'timeout-ms' is omitted clearly explained. --- .../devicetree/bindings/input/input-reset.txt | 34 ++++++++++++++++++++ drivers/tty/sysrq.c | 37 ++++++++++++++++++++++ 2 files changed, 71 insertions(+) create mode 100644 Documentation/devicetree/bindings/input/input-reset.txt diff --git a/Documentation/devicetree/bindings/input/input-reset.txt b/Documentation/devicetree/bindings/input/input-reset.txt new file mode 100644 index 0000000..13421a9 --- /dev/null +++ b/Documentation/devicetree/bindings/input/input-reset.txt @@ -0,0 +1,34 @@ +Input: sysrq reset sequence + +A simple binding to represent a set of keys as described in +include/uapi/linux/input.h. This is to communicate a +sequence of keys to the sysrq driver. Upon holding the keys +for a specified amount of time (if specified) the system is +sync'ed and reset. + +Key sequences are global to the system but all the keys in a +set must be coming from the same input device. + +The /chosen node should contain a 'linux,sysrq-reset-seq' child +node to define a set of keys. + +Required property: +sysrq-reset-seq: array of Linux keycodes, one keycode per cell. + +Optional property: +timeout-ms: duration keys must be pressed together in milliseconds +before generating a sysrq. If omitted the system is rebooted +immediately when a valid sequence has beend recognized. + +Example: + + chosen { + linux,sysrq-reset-seq { + keyset = <0x03 + 0x04 + 0x0a>; + timeout-ms = <3000>; + }; + }; + +Would represent KEY_2, KEY_3 and KEY_9. diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c index d5cc3ac..b04a24d 100644 --- a/drivers/tty/sysrq.c +++ b/drivers/tty/sysrq.c @@ -45,6 +45,7 @@ #include #include #include +#include #include #include @@ -681,6 +682,34 @@ static void sysrq_detect_reset_sequence(struct sysrq_state *state, } } +static void sysrq_of_get_keyreset_config(void) +{ + u32 key; + struct device_node *np; + struct property *prop; + const __be32 *p; + + np = of_find_node_by_path("/chosen/linux,sysrq-reset-seq"); + if (!np) { + pr_debug("No sysrq node found"); + return; + } + + /* reset in case a __weak definition was present */ + sysrq_reset_seq_len = 0; + + of_property_for_each_u32(np, "keyset", prop, p, key) { + if ((key == KEY_RESERVED || key > KEY_MAX) || + (sysrq_reset_seq_len == SYSRQ_KEY_RESET_MAX)) + break; + + sysrq_reset_seq[sysrq_reset_seq_len++] = (unsigned short)key; + } + + /* get reset timeout if any */ + of_property_read_u32(np, "timeout-ms", &sysrq_reset_downtime_ms); +} + static void sysrq_reinject_alt_sysrq(struct work_struct *work) { struct sysrq_state *sysrq = @@ -914,6 +943,7 @@ static inline void sysrq_register_handler(void) int error; int i; + /* first check if a __weak interface was instantiated */ for (i = 0; i < ARRAY_SIZE(sysrq_reset_seq); i++) { key = platform_sysrq_reset_seq[i]; if (key == KEY_RESERVED || key > KEY_MAX) @@ -922,6 +952,13 @@ static inline void sysrq_register_handler(void) sysrq_reset_seq[sysrq_reset_seq_len++] = key; } + /* + * DT configuration takes precedence over anything + * that would have been defined via the __weak + * interface + */ + sysrq_of_get_keyreset_config(); + error = input_register_handler(&sysrq_handler); if (error) pr_err("Failed to register input handler, error %d", error);