From patchwork Tue Apr 2 06:30:37 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: William Breathitt Gray X-Patchwork-Id: 10881063 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 313A91669 for ; Tue, 2 Apr 2019 06:30:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1C121286D5 for ; Tue, 2 Apr 2019 06:30:43 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0FFB5286E6; Tue, 2 Apr 2019 06:30:43 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3CDDC286D5 for ; Tue, 2 Apr 2019 06:30:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729063AbfDBGae (ORCPT ); Tue, 2 Apr 2019 02:30:34 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:33291 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726690AbfDBGad (ORCPT ); Tue, 2 Apr 2019 02:30:33 -0400 Received: by mail-pg1-f194.google.com with SMTP id b12so6039533pgk.0; Mon, 01 Apr 2019 23:30:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=D3TIN7GVmzZf2vc4K8K5AuMdS/7XAlZhj8cjpR6bpjs=; b=JsVsUpDoZ8mC7tNQGcsRzmeEU0alBBVqm5MslrRSC6T2ZRVw+zUqt5rkWJPxMciLun u1i9k9xtM7TlZs7oEbetVzr+i3i4A49Y87c5Mnd8cseTs6iZILi+vQRtwcijBUdNfCRb +nTtiJ1hSXrpi2IK5px1Acc9Z4uLWXcrCIikshC3zYiwtMYyHAh8twl5Iy3ELpSpOvT4 Uo3t9KZC8d5Egtkyew32U3Qx7qUMG6Om1tO8BNDXO30ragx0q7HIT5cpWIZOjUYVnoT+ SoXITqElV2aKCzMkVYJGgaYBQYAiVGcrKp3GZezuaueYlH+Zlp4NqkPcIDSkw9996Gt0 V8VQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=D3TIN7GVmzZf2vc4K8K5AuMdS/7XAlZhj8cjpR6bpjs=; b=UpTC3znTdvzIx0bXHl6zhRtfOicaKkB0+TDhk3rABUoi6JUTcYIeckPsZBnRcoWWR9 FRTeSTbgQ0q2ICgF9KMTWDy8xaQ10qy+n6XKNwgYposeILdoFkA7I+SUKweS+D0dBXhJ +u45i8EaiWzHIyy1fb9HSkSJ9AkH//948ez2X3gBZsCJ3jz3F0VLMEfPNB0K++af4NPH 1KVhUmUkcqRgYp4v8/F51T4MbuWdCQpRFhGM7cENJoPlxVL5VgjaQmIyRcZebjzfjrZP mk4I3rrR85ngR74zUm6aUrV0pH6vrbhrgb7j4a2QW4Pc8HG7jfAo1wz2UYGMIk3nWg5Q nFlg== X-Gm-Message-State: APjAAAWKwmmgVGAhl4oofCNqNv5hFr55bbw5JjCOafTxWGRbD9NPqRla iCpyce8Q3VdhlssNJbASlNg= X-Google-Smtp-Source: APXvYqzSeGoSAa/6Nug0zyY9tEFUnup6xUq83Lxmbp4KhfmcdS/VfA1Xkq1I1CPJp/NHDZYDlGfFwQ== X-Received: by 2002:a63:fc43:: with SMTP id r3mr47039829pgk.44.1554186632252; Mon, 01 Apr 2019 23:30:32 -0700 (PDT) Received: from localhost.localdomain ([2001:268:c0a5:4ce0:c70:4af9:86e2:2]) by smtp.gmail.com with ESMTPSA id a17sm19327289pfj.123.2019.04.01.23.30.21 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 01 Apr 2019 23:30:31 -0700 (PDT) From: William Breathitt Gray To: gregkh@linuxfoundation.org Cc: jic23@kernel.org, linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, fabrice.gasnier@st.com, benjamin.gaignard@st.com, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, akpm@linux-foundation.org, david@lechnology.com, robh+dt@kernel.org, mark.rutland@arm.com, shawnguo@kernel.org, leoyang.li@nxp.com, daniel.lezcano@linaro.org, tglx@linutronix.de, thierry.reding@gmail.com, esben@haabendal.dk, linux-pwm@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, patrick.havelange@essensium.com, William Breathitt Gray , Jonathan Cameron Subject: [PATCH v10 02/18] counter: Documentation: Add Generic Counter sysfs documentation Date: Tue, 2 Apr 2019 15:30:37 +0900 Message-Id: X-Mailer: git-send-email 2.21.0 In-Reply-To: References: MIME-Version: 1.0 Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patch adds standard documentation for the userspace sysfs attributes of the Generic Counter interface. Reviewed-by: Jonathan Cameron Signed-off-by: William Breathitt Gray --- Documentation/ABI/testing/sysfs-bus-counter | 230 ++++++++++++++++++++ MAINTAINERS | 1 + 2 files changed, 231 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-counter diff --git a/Documentation/ABI/testing/sysfs-bus-counter b/Documentation/ABI/testing/sysfs-bus-counter new file mode 100644 index 000000000000..566bd99fe0a5 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-counter @@ -0,0 +1,230 @@ +What: /sys/bus/counter/devices/counterX/countY/count +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Count data of Count Y represented as a string. + +What: /sys/bus/counter/devices/counterX/countY/ceiling +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Count value ceiling for Count Y. This is the upper limit for the + respective counter. + +What: /sys/bus/counter/devices/counterX/countY/floor +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Count value floor for Count Y. This is the lower limit for the + respective counter. + +What: /sys/bus/counter/devices/counterX/countY/count_mode +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Count mode for channel Y. The ceiling and floor values for + Count Y are used by the count mode where required. The following + count modes are available: + + normal: + Counting is continuous in either direction. + + range limit: + An upper or lower limit is set, mimicking limit switches + in the mechanical counterpart. The upper limit is set to + the Count Y ceiling value, while the lower limit is set + to the Count Y floor value. The counter freezes at + count = ceiling when counting up, and at count = floor + when counting down. At either of these limits, the + counting is resumed only when the count direction is + reversed. + + non-recycle: + The counter is disabled whenever a counter overflow or + underflow takes place. The counter is re-enabled when a + new count value is loaded to the counter via a preset + operation or direct write. + + modulo-n: + A count value boundary is set between the Count Y floor + value and the Count Y ceiling value. The counter is + reset to the Count Y floor value at count = ceiling when + counting up, while the counter is set to the Count Y + ceiling value at count = floor when counting down; the + counter does not freeze at the boundary points, but + counts continuously throughout. + +What: /sys/bus/counter/devices/counterX/countY/count_mode_available +What: /sys/bus/counter/devices/counterX/countY/error_noise_available +What: /sys/bus/counter/devices/counterX/countY/function_available +What: /sys/bus/counter/devices/counterX/countY/signalZ_action_available +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Discrete set of available values for the respective Count Y + configuration are listed in this file. Values are delimited by + newline characters. + +What: /sys/bus/counter/devices/counterX/countY/direction +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Read-only attribute that indicates the count direction of Count + Y. Two count directions are available: forward and backward. + + Some counter devices are able to determine the direction of + their counting. For example, quadrature encoding counters can + determine the direction of movement by evaluating the leading + phase of the respective A and B quadrature encoding signals. + This attribute exposes such count directions. + +What: /sys/bus/counter/devices/counterX/countY/enable +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Whether channel Y counter is enabled. Valid attribute values are + boolean. + + This attribute is intended to serve as a pause/unpause mechanism + for Count Y. Suppose a counter device is used to count the total + movement of a conveyor belt: this attribute allows an operator + to temporarily pause the counter, service the conveyor belt, + and then finally unpause the counter to continue where it had + left off. + +What: /sys/bus/counter/devices/counterX/countY/error_noise +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Read-only attribute that indicates whether excessive noise is + present at the channel Y counter inputs. + +What: /sys/bus/counter/devices/counterX/countY/function +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Count function mode of Count Y; count function evaluation is + triggered by conditions specified by the Count Y signalZ_action + attributes. The following count functions are available: + + increase: + Accumulated count is incremented. + + decrease: + Accumulated count is decremented. + + pulse-direction: + Rising edges on signal A updates the respective count. + The input level of signal B determines direction. + + quadrature x1 a: + If direction is forward, rising edges on quadrature pair + signal A updates the respective count; if the direction + is backward, falling edges on quadrature pair signal A + updates the respective count. Quadrature encoding + determines the direction. + + quadrature x1 b: + If direction is forward, rising edges on quadrature pair + signal B updates the respective count; if the direction + is backward, falling edges on quadrature pair signal B + updates the respective count. Quadrature encoding + determines the direction. + + quadrature x2 a: + Any state transition on quadrature pair signal A updates + the respective count. Quadrature encoding determines the + direction. + + quadrature x2 b: + Any state transition on quadrature pair signal B updates + the respective count. Quadrature encoding determines the + direction. + + quadrature x4: + Any state transition on either quadrature pair signals + updates the respective count. Quadrature encoding + determines the direction. + +What: /sys/bus/counter/devices/counterX/countY/name +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Read-only attribute that indicates the device-specific name of + Count Y. If possible, this should match the name of the + respective channel as it appears in the device datasheet. + +What: /sys/bus/counter/devices/counterX/countY/preset +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + If the counter device supports preset registers -- registers + used to load counter channels to a set count upon device-defined + preset operation trigger events -- the preset count for channel + Y is provided by this attribute. + +What: /sys/bus/counter/devices/counterX/countY/preset_enable +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Whether channel Y counter preset operation is enabled. Valid + attribute values are boolean. + +What: /sys/bus/counter/devices/counterX/countY/signalZ_action +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Action mode of Count Y for Signal Z. This attribute indicates + the condition of Signal Z that triggers the count function + evaluation for Count Y. The following action modes are + available: + + none: + Signal does not trigger the count function. In + Pulse-Direction count function mode, this Signal is + evaluated as Direction. + + rising edge: + Low state transitions to high state. + + falling edge: + High state transitions to low state. + + both edges: + Any state transition. + +What: /sys/bus/counter/devices/counterX/name +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Read-only attribute that indicates the device-specific name of + the Counter. This should match the name of the device as it + appears in its respective datasheet. + +What: /sys/bus/counter/devices/counterX/num_counts +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Read-only attribute that indicates the total number of Counts + belonging to the Counter. + +What: /sys/bus/counter/devices/counterX/num_signals +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Read-only attribute that indicates the total number of Signals + belonging to the Counter. + +What: /sys/bus/counter/devices/counterX/signalY/signal +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Signal data of Signal Y represented as a string. + +What: /sys/bus/counter/devices/counterX/signalY/name +KernelVersion: 5.2 +Contact: linux-iio@vger.kernel.org +Description: + Read-only attribute that indicates the device-specific name of + Signal Y. If possible, this should match the name of the + respective signal as it appears in the device datasheet. diff --git a/MAINTAINERS b/MAINTAINERS index ef497d470501..af701863a249 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3970,6 +3970,7 @@ COUNTER SUBSYSTEM M: William Breathitt Gray L: linux-iio@vger.kernel.org S: Maintained +F: Documentation/ABI/testing/sysfs-bus-counter* F: drivers/counter/ F: include/linux/counter.h F: include/linux/counter_enum.h