From patchwork Mon Mar 6 09:48:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Conor Dooley X-Patchwork-Id: 1752277 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=2620:137:e000::1:20; helo=out1.vger.email; envelope-from=linux-pwm-owner@vger.kernel.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=microchip.com header.i=@microchip.com header.a=rsa-sha256 header.s=mchp header.b=bZh9s5Vv; dkim-atps=neutral Received: from out1.vger.email (out1.vger.email [IPv6:2620:137:e000::1:20]) by legolas.ozlabs.org (Postfix) with ESMTP id 4PVYhv6gsjz246K for ; Mon, 6 Mar 2023 20:50:07 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229536AbjCFJuD (ORCPT ); Mon, 6 Mar 2023 04:50:03 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36602 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229667AbjCFJuB (ORCPT ); Mon, 6 Mar 2023 04:50:01 -0500 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33E82206B9; Mon, 6 Mar 2023 01:49:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1678096198; x=1709632198; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=0SyElCUWTlCle3k2VOdcQEbG3TLOBs5Dv4yCPL7zPl8=; b=bZh9s5VvfIFN/GwOIjIl4IUNGpDRxAby4Bf1QarMRc/v9EnzrTP2CM1L PIWtbc3Opjz1PTH54iWEPrtfLak5FPbkoYk5rSL0K0jFI1q8OR1VuddYT 4knEy45EPvd4Pf/tWkdblBtBR7bSijeb/O9WnAh47TzkTOg8xUgKLy8Wo VUkBCwXBkGL+k1HoA6IU07VXsjeGpZMBQPB9lxMiRSBCPAwmDpMWqUDhB WMMy7nnn2GVrIXdexXkeovb3Wc0ft6+PV2o1FG7812di3tFwTH6sSIjVX 71NCQOk2u+NZjL8U3S8sF0b1/91z7t9z4SVGm+t9ftamG3q0ez5lRq34N A==; X-IronPort-AV: E=Sophos;i="5.98,236,1673938800"; d="scan'208";a="203807069" Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa2.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 06 Mar 2023 02:49:57 -0700 Received: from chn-vm-ex02.mchp-main.com (10.10.85.144) by chn-vm-ex01.mchp-main.com (10.10.85.143) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.16; Mon, 6 Mar 2023 02:49:56 -0700 Received: from wendy.microchip.com (10.10.115.15) by chn-vm-ex02.mchp-main.com (10.10.85.144) with Microsoft SMTP Server id 15.1.2507.16 via Frontend Transport; Mon, 6 Mar 2023 02:49:55 -0700 From: Conor Dooley To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K=C3=B6n?= =?utf-8?q?ig?= CC: Daire McNamara , , , , Conor Dooley Subject: [PATCH v14 0/2] Microchip Soft IP corePWM driver Date: Mon, 6 Mar 2023 09:48:57 +0000 Message-ID: <20230306094858.1614819-1-conor.dooley@microchip.com> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=3956; i=conor.dooley@microchip.com; h=from:subject; bh=0SyElCUWTlCle3k2VOdcQEbG3TLOBs5Dv4yCPL7zPl8=; b=owGbwMvMwCFWscWwfUFT0iXG02pJDCms21lM7Kw27U24bxQnd9xa5Ou7rd314v/LJ63fN3HmzWoT YYP5HaUsDGIcDLJiiiyJt/tapNb/cdnh3PMWZg4rE8gQBi5OAZjIbi2Gv8K1C5+sutZ/+fCF9uao9e XxPV3/Lt3Yd9gzZ3mDt+a5ghCG/yH2/Bf3LZjiw3fHa46D0VtbrsptW85k7k7erbT0cFCxKzMA X-Developer-Key: i=conor.dooley@microchip.com; a=openpgp; fpr=F9ECA03CF54F12CD01F1655722E2C55B37CF380C X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, RCVD_IN_MSPIKE_H2,SPF_HELO_PASS,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-pwm@vger.kernel.org Hey Uwe, all, v14 is rebased on top of v6.3-rc1. Uwe & I had a long back and forth about period calculations on v13, my ultimate conclusion being that, after some testing of the "corrected" calculation in hardware, the original calculation was correct. I think we had gotten sucked into discussion the calculation of the period itself, when we were in fact trying to calculate a bound on the period instead. That discussion is here: https://lore.kernel.org/linux-pwm/Y+ow8tfAHo1yv1XL@wendy/ Thanks, Conor. Changes since v13: - couple bits of cleanup to apply_locked(), suggested by Uwe - move the overhead waiting for a change to be applied, for channels with shadow registers, to subsequent calls to apply(). This has the benefit of only waiting when two calls to apply() are close in time rather than eating the delay in every call. Changes since v11: - swap a "bare" multiply & divide for the corresponding helper to prevent overflow - factor out duplicate clk rate acquisition & period calculation - make the period calculation return void by checking the validity of the clock rate in the caller - drop the binding & dt patch, they're on-track for v6.2 via my tree Changes since v10: - reword some comments - try to assign the period if a disable is requested - drop a cast around a u8 -> u16 conversion - fix a check on period_steps that should be on the hw_ variant - split up the period calculation in get_state() to fix the result on 32 bit - add a rate variable in get_state() to only call get_rate() once - redo the locking as suggested to make it more straightforward. - stop checking for enablement in get_state() that was working around intended behaviour of the sysfs interface Changes since v9: - fixed the missing unlock that Dan reported Changes since v8: - fixed a(nother) raw 64 bit division (& built it for riscv32!) - added a check to make sure we don't try to sleep for 0 us Changes since v7: - rebased on 6.0-rc1 - reworded comments you highlighted in v7 - fixed the overkill sleeping - removed the unused variables in calc_duty - added some extra comments to explain behaviours you questioned in v7 - make the mutexes un-interruptible - fixed added the 1s you suggested for the if(period_locked) logic - added setup of the channel_enabled shadowing - fixed the period reporting for the negedge == posedge case in get_state() I had to add the enabled check, as otherwise it broke setting the period for the first time out of reset. - added a test for invalid PERIOD_STEPS values, in which case we abort if we cannot fix the period Changes from v6: - Dropped an unused variable that I'd missed - Actually check the return values of the mutex lock()s - Re-rebased on -next for the MAINTAINERS patch (again...) Changes from v5: - switched to a mutex b/c we must sleep with the lock taken - simplified the locking in apply() and added locking to get_state() - reworked apply() as requested - removed the loop in the period calculation (thanks Uwe!) - add a copy of the enable registers in the driver to save on reads. - remove the second (useless) write to sync_update - added some missing rounding in get_state() - couple other minor cleanups as requested in: https://lore.kernel.org/linux-riscv/20220709160206.cw5luo7kxdshoiua@pengutronix.de/ Changes from v4: - dropped some accidentally added files Changes before v4: https://lore.kernel.org/linux-pwm/20220721172109.941900-1-mail@conchuod.ie Conor Dooley (2): pwm: add microchip soft ip corePWM driver MAINTAINERS: add pwm to PolarFire SoC entry MAINTAINERS | 1 + drivers/pwm/Kconfig | 10 + drivers/pwm/Makefile | 1 + drivers/pwm/pwm-microchip-core.c | 441 +++++++++++++++++++++++++++++++ 4 files changed, 453 insertions(+) create mode 100644 drivers/pwm/pwm-microchip-core.c