From mboxrd@z Thu Jan 1 00:00:00 1970 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=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 8CB8DC55186 for ; Fri, 24 Apr 2020 21:03:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6A66620661 for ; Fri, 24 Apr 2020 21:03:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="hphE9Eht" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726192AbgDXVDU (ORCPT ); Fri, 24 Apr 2020 17:03:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48956 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726119AbgDXVDU (ORCPT ); Fri, 24 Apr 2020 17:03:20 -0400 Received: from mail-pj1-x1042.google.com (mail-pj1-x1042.google.com [IPv6:2607:f8b0:4864:20::1042]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 356CBC09B048; Fri, 24 Apr 2020 14:03:20 -0700 (PDT) Received: by mail-pj1-x1042.google.com with SMTP id a7so4386094pju.2; Fri, 24 Apr 2020 14:03:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=ZknRY+ED4Rci10RQgZ5KLUNuZwg2P5QWQY0A1F9mV4E=; b=hphE9Ehti93jXXiIfv9SCmt1TeErLdGL89RPBfZCeVjiSHwooSXmlWfqfRI2mDhaCo 1p3iY0nxZgUwElQxHhNtaefO3Vqlm9qd/ccZSO8ad15rHth3GhnMzsAaBBab8LgKknkv 7uMwMK/R639q+MT8eSJUHKP+Y/H/FRNKbWk8cOK7uyKc8YpI+vUbvuP9vadsdZUFBvG8 ZvC87Ii2vT6oypL5OEC+xWef5/MUshNGnxdoenqgcYFy7/xsNa+MKteu2RGzviOLMKgx wOZipQ/xXjYnoC6Jz7D5sW1GaQkeRbrnKqyLAWetLOsIPk1ti4nsv8IccaRL6I5v2sjd lYng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=ZknRY+ED4Rci10RQgZ5KLUNuZwg2P5QWQY0A1F9mV4E=; b=Nwn+WAgHue0WeEUWWjxIfl1P+21XaXe7mldJ1XI0axOFULYF6YWXgT9rEIthz7U+ud jHoQS/JCckTddWMSJe9gOhsrnGz713oqggSM3ew3LOczBBNCpZFfMSTyBi9umLpeCVY6 NSZZ4aK6X+ujkELlyY2oaesjq2FNW9w5afzzurYoHXXnmN71xRmJ7DiiSvJDae7EsfIl 6Iq4tF9x7McEECwX37yDPxtrcS3pTYRymuH5XoQdy8ILNAOJcMKHS49c6zIDuZHgbr5Z 059EBZRt8tk9JLfh6LXXx3N8fJd+vkIGewzWqSlI3WdLJe55Wqccki6fv+ufTMuGXbf2 nMiw== X-Gm-Message-State: AGi0Pub548a8lZZb3X+1fFMQTRklhiTYzweEcWYZRCYR56Nws5oOYpf8 4AVNuN7if3InicZfswmhHAjSWvvB X-Google-Smtp-Source: APiQypKJZGHlzUhqTrUKYo3As8yT7reZGH+s/LyNtQsjNcDivk9xdGtLO7MoIPiZIte2R8ne7f9BwQ== X-Received: by 2002:a17:902:b78b:: with SMTP id e11mr10926839pls.311.1587762199439; Fri, 24 Apr 2020 14:03:19 -0700 (PDT) Received: from dtor-ws ([2620:15c:202:201:3c2a:73a9:c2cf:7f45]) by smtp.gmail.com with ESMTPSA id r23sm6762811pfr.64.2020.04.24.14.03.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Apr 2020 14:03:18 -0700 (PDT) Date: Fri, 24 Apr 2020 14:03:16 -0700 From: Dmitry Torokhov To: Rajat Jain Cc: dtor@google.com, Rob Herring , Mark Rutland , Kate Stewart , Enrico Weigelt , Greg Kroah-Hartman , Thomas Gleixner , Allison Randal , "Rafael J. Wysocki" , Stephen Boyd , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, furquan@google.com, dlaurie@google.com, bleung@google.com, zentaro@google.com, dbehr@google.com, rajatxjain@gmail.com Subject: Re: [PATCH v4 2/5] Input: atkbd: Expose function row physical map to userspace Message-ID: <20200424210316.GI125362@dtor-ws> References: <20200328185916.98423-1-rajatja@google.com> <20200328185916.98423-2-rajatja@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200328185916.98423-2-rajatja@google.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Rajat, On Sat, Mar 28, 2020 at 11:59:13AM -0700, Rajat Jain wrote: > Certain keyboards have their top-row keys intended > for actions such as "Browser back", "Browser Refresh", "Fullscreen" > etc as their primary mode, thus they will send physical codes for those > actions. Further, they don't have a dedicated "Fn" key so don't have > the capability to generate function key codes (e.g. F1, F2 etc..). > However in this case, if userspace still wants to "synthesize" those > function keys using the top row action keys, it needs to know the > physical position of the top row keys. (Essentially a mapping between > usage codes and a physical location in the top row). > > This patch enhances the atkbd driver to receive such a mapping from the > firmware / device tree, and expose it to userspace in the form of > a function-row-physmap attribute. The attribute would be a space > separated ordered list of physical codes, for the keys in the function > row, in left-to-right order. > > The attribute will only be present if the kernel knows about such > mapping, otherwise the attribute shall not be visible. > > Signed-off-by: Rajat Jain > --- > v4: Same as v3 > v3: Change to dev_dbg and remove unecessary error check > v2: Remove the Change-Id from the commit log > > drivers/input/keyboard/atkbd.c | 56 ++++++++++++++++++++++++++++++++++ > 1 file changed, 56 insertions(+) > > diff --git a/drivers/input/keyboard/atkbd.c b/drivers/input/keyboard/atkbd.c > index 7e3eae54c1926..3b20aba1861cd 100644 > --- a/drivers/input/keyboard/atkbd.c > +++ b/drivers/input/keyboard/atkbd.c > @@ -24,6 +24,7 @@ > #include > #include > #include > +#include > > #define DRIVER_DESC "AT and PS/2 keyboard driver" > > @@ -63,6 +64,8 @@ static bool atkbd_terminal; > module_param_named(terminal, atkbd_terminal, bool, 0); > MODULE_PARM_DESC(terminal, "Enable break codes on an IBM Terminal keyboard connected via AT/PS2"); > > +#define MAX_FUNCTION_ROW_KEYS 24 > + > /* > * Scancode to keycode tables. These are just the default setting, and > * are loadable via a userland utility. > @@ -230,6 +233,9 @@ struct atkbd { > > /* Serializes reconnect(), attr->set() and event work */ > struct mutex mutex; > + > + u16 function_row_physmap[MAX_FUNCTION_ROW_KEYS]; > + int num_function_row_keys; > }; > > /* > @@ -283,6 +289,7 @@ static struct device_attribute atkbd_attr_##_name = \ > __ATTR(_name, S_IRUGO, atkbd_do_show_##_name, NULL); > > ATKBD_DEFINE_RO_ATTR(err_count); > +ATKBD_DEFINE_RO_ATTR(function_row_physmap); > > static struct attribute *atkbd_attributes[] = { > &atkbd_attr_extra.attr, > @@ -292,11 +299,42 @@ static struct attribute *atkbd_attributes[] = { > &atkbd_attr_softrepeat.attr, > &atkbd_attr_softraw.attr, > &atkbd_attr_err_count.attr, > + &atkbd_attr_function_row_physmap.attr, > NULL > }; > > +static ssize_t atkbd_show_function_row_physmap(struct atkbd *atkbd, char *buf) > +{ > + ssize_t size = 0; > + int i; > + > + if (!atkbd->num_function_row_keys) > + return 0; > + > + for (i = 0; i < atkbd->num_function_row_keys; i++) > + size += sprintf(buf + size, "%02X ", > + atkbd->function_row_physmap[i]); > + size += sprintf(buf + size, "\n"); Can we change this to scnprintf() with PAGE_SIZE as the initial limit? > + return size; > +} > + > +static umode_t atkbd_attr_is_visible(struct kobject *kobj, > + struct attribute *attr, int i) > +{ > + struct device *dev = container_of(kobj, struct device, kobj); > + struct serio *serio = to_serio_port(dev); > + struct atkbd *atkbd = serio_get_drvdata(serio); > + > + if (attr == &atkbd_attr_function_row_physmap.attr && > + !atkbd->num_function_row_keys) > + return 0; > + > + return attr->mode; > +} > + > static struct attribute_group atkbd_attribute_group = { > .attrs = atkbd_attributes, > + .is_visible = atkbd_attr_is_visible, > }; > > static const unsigned int xl_table[] = { > @@ -1121,6 +1159,22 @@ static void atkbd_set_device_attrs(struct atkbd *atkbd) > } > } > > +static void atkbd_parse_fwnode_data(struct serio *serio) > +{ > + struct atkbd *atkbd = serio_get_drvdata(serio); > + struct device *dev = &serio->dev; > + int n; > + > + /* Parse "function-row-physmap" property */ > + n = device_property_count_u16(dev, "function-row-physmap"); I think for ACPI case it does not matter, but if we ever have device tree using it, it will lead to less errors if we use u32 as the element size. Do you mind switching to it? > + if (n > 0 && n <= MAX_FUNCTION_ROW_KEYS && > + !device_property_read_u16_array(dev, "function-row-physmap", > + atkbd->function_row_physmap, n)) { > + atkbd->num_function_row_keys = n; > + dev_dbg(dev, "FW reported %d function-row key locations\n", n); > + } > +} > + > /* > * atkbd_connect() is called when the serio module finds an interface > * that isn't handled yet by an appropriate device driver. We check if > @@ -1184,6 +1238,8 @@ static int atkbd_connect(struct serio *serio, struct serio_driver *drv) > atkbd->id = 0xab00; > } > > + atkbd_parse_fwnode_data(serio); > + > atkbd_set_keycode_table(atkbd); > atkbd_set_device_attrs(atkbd); > Thanks. -- Dmitry