From patchwork Thu Jan 14 18:57:33 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Baruch Siach X-Patchwork-Id: 363138 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 32023C433E6 for ; Thu, 14 Jan 2021 18:58:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3BAA23B31 for ; Thu, 14 Jan 2021 18:58:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726734AbhANS6b (ORCPT ); Thu, 14 Jan 2021 13:58:31 -0500 Received: from guitar.tcltek.co.il ([192.115.133.116]:47411 "EHLO mx.tkos.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726986AbhANS6b (ORCPT ); Thu, 14 Jan 2021 13:58:31 -0500 Received: from tarshish.tkos.co.il (unknown [10.0.8.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx.tkos.co.il (Postfix) with ESMTPS id A38E24407B2; Thu, 14 Jan 2021 20:57:47 +0200 (IST) From: Baruch Siach To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K?= =?utf-8?b?w7ZuaWc=?= , Lee Jones , Linus Walleij , Bartosz Golaszewski Cc: Baruch Siach , Russell King , Andrew Lunn , Gregory Clement , Sebastian Hesselbarth , Thomas Petazzoni , Chris Packham , Sascha Hauer , Ralph Sennhauser , linux-pwm@vger.kernel.org, linux-gpio@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 1/5] gpio: mvebu: fix pwm .get_state period calculation Date: Thu, 14 Jan 2021 20:57:33 +0200 Message-Id: <588373a200d20da0fa6c2a6c7f1928b4818097e9.1610628807.git.baruch@tkos.co.il> X-Mailer: git-send-email 2.29.2 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org The period is the sum of on and off values. That is, calculate period as ($on + $off) / clkrate instead of $off / clkrate - $on / clkrate that makes no sense. Reported-by: Russell King Reviewed-by: Uwe Kleine-König Fixes: 757642f9a584e ("gpio: mvebu: Add limited PWM support") Signed-off-by: Baruch Siach --- drivers/gpio/gpio-mvebu.c | 19 ++++++++----------- 1 file changed, 8 insertions(+), 11 deletions(-) diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index 672681a976f5..a912a8fed197 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -676,20 +676,17 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, else state->duty_cycle = 1; + val = (unsigned long long) u; /* on duration */ regmap_read(mvpwm->regs, mvebu_pwmreg_blink_off_duration(mvpwm), &u); - val = (unsigned long long) u * NSEC_PER_SEC; + val += (unsigned long long) u; /* period = on + off duration */ + val *= NSEC_PER_SEC; do_div(val, mvpwm->clk_rate); - if (val < state->duty_cycle) { + if (val > UINT_MAX) + state->period = UINT_MAX; + else if (val) + state->period = val; + else state->period = 1; - } else { - val -= state->duty_cycle; - if (val > UINT_MAX) - state->period = UINT_MAX; - else if (val) - state->period = val; - else - state->period = 1; - } regmap_read(mvchip->regs, GPIO_BLINK_EN_OFF + mvchip->offset, &u); if (u) From patchwork Thu Jan 14 18:57:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Baruch Siach X-Patchwork-Id: 364119 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 8A589C4332B for ; Thu, 14 Jan 2021 18:58:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4C84523B31 for ; Thu, 14 Jan 2021 18:58:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727134AbhANS6d (ORCPT ); Thu, 14 Jan 2021 13:58:33 -0500 Received: from guitar.tcltek.co.il ([192.115.133.116]:47425 "EHLO mx.tkos.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726287AbhANS6d (ORCPT ); Thu, 14 Jan 2021 13:58:33 -0500 Received: from tarshish.tkos.co.il (unknown [10.0.8.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx.tkos.co.il (Postfix) with ESMTPS id CDEBD4407E8; Thu, 14 Jan 2021 20:57:49 +0200 (IST) From: Baruch Siach To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K?= =?utf-8?b?w7ZuaWc=?= , Lee Jones , Linus Walleij , Bartosz Golaszewski Cc: Baruch Siach , Andrew Lunn , Gregory Clement , Russell King , Sebastian Hesselbarth , Thomas Petazzoni , Chris Packham , Sascha Hauer , Ralph Sennhauser , linux-pwm@vger.kernel.org, linux-gpio@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 2/5] gpio: mvebu: improve pwm period calculation accuracy Date: Thu, 14 Jan 2021 20:57:34 +0200 Message-Id: X-Mailer: git-send-email 2.29.2 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Change 'off' register value calculation from $off = (period - duty_cycle) * clkrate / NSEC_PER_SEC to $off = (period * clkrate / NSEC_PER_SEC) - $on That is, divide the full period value to reduce rounding error. Reported-by: Uwe Kleine-König Reviewed-by: Uwe Kleine-König Signed-off-by: Baruch Siach --- drivers/gpio/gpio-mvebu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index a912a8fed197..c424d88e9e2b 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -715,9 +715,9 @@ static int mvebu_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, else on = 1; - val = (unsigned long long) mvpwm->clk_rate * - (state->period - state->duty_cycle); + val = (unsigned long long) mvpwm->clk_rate * state->period; do_div(val, NSEC_PER_SEC); + val -= on; if (val > UINT_MAX) return -EINVAL; if (val) From patchwork Thu Jan 14 18:57:35 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Baruch Siach X-Patchwork-Id: 363137 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 C10FDC43331 for ; Thu, 14 Jan 2021 18:58:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 958D223B31 for ; Thu, 14 Jan 2021 18:58:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727872AbhANS6f (ORCPT ); Thu, 14 Jan 2021 13:58:35 -0500 Received: from guitar.tcltek.co.il ([192.115.133.116]:47435 "EHLO mx.tkos.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726287AbhANS6f (ORCPT ); Thu, 14 Jan 2021 13:58:35 -0500 Received: from tarshish.tkos.co.il (unknown [10.0.8.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx.tkos.co.il (Postfix) with ESMTPS id 0FE5244081D; Thu, 14 Jan 2021 20:57:51 +0200 (IST) From: Baruch Siach To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K?= =?utf-8?b?w7ZuaWc=?= , Lee Jones , Linus Walleij , Bartosz Golaszewski Cc: Baruch Siach , Andrew Lunn , Gregory Clement , Russell King , Sebastian Hesselbarth , Thomas Petazzoni , Chris Packham , Sascha Hauer , Ralph Sennhauser , linux-pwm@vger.kernel.org, linux-gpio@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 3/5] gpio: mvebu: make pwm .get_state closer to idempotent Date: Thu, 14 Jan 2021 20:57:35 +0200 Message-Id: X-Mailer: git-send-email 2.29.2 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Round up the divisions in .get_state() to make applying the read out configuration idempotent in most cases as .apply rounds down. Reported-by: Uwe Kleine-König Reviewed-by: Uwe Kleine-König Signed-off-by: Baruch Siach --- drivers/gpio/gpio-mvebu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index c424d88e9e2b..8673ba77af5a 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -668,7 +668,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, regmap_read(mvpwm->regs, mvebu_pwmreg_blink_on_duration(mvpwm), &u); val = (unsigned long long) u * NSEC_PER_SEC; - do_div(val, mvpwm->clk_rate); + val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate); if (val > UINT_MAX) state->duty_cycle = UINT_MAX; else if (val) @@ -680,7 +680,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, regmap_read(mvpwm->regs, mvebu_pwmreg_blink_off_duration(mvpwm), &u); val += (unsigned long long) u; /* period = on + off duration */ val *= NSEC_PER_SEC; - do_div(val, mvpwm->clk_rate); + val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate); if (val > UINT_MAX) state->period = UINT_MAX; else if (val) From patchwork Thu Jan 14 18:57:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Baruch Siach X-Patchwork-Id: 364118 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 2D1A7C43332 for ; Thu, 14 Jan 2021 18:58:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DC06923B31 for ; Thu, 14 Jan 2021 18:58:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728009AbhANS6h (ORCPT ); Thu, 14 Jan 2021 13:58:37 -0500 Received: from guitar.tcltek.co.il ([192.115.133.116]:47448 "EHLO mx.tkos.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726287AbhANS6h (ORCPT ); Thu, 14 Jan 2021 13:58:37 -0500 Received: from tarshish.tkos.co.il (unknown [10.0.8.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx.tkos.co.il (Postfix) with ESMTPS id 1637C440820; Thu, 14 Jan 2021 20:57:54 +0200 (IST) From: Baruch Siach To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K?= =?utf-8?b?w7ZuaWc=?= , Lee Jones , Linus Walleij , Bartosz Golaszewski Cc: Baruch Siach , Andrew Lunn , Gregory Clement , Russell King , Sebastian Hesselbarth , Thomas Petazzoni , Chris Packham , Sascha Hauer , Ralph Sennhauser , linux-pwm@vger.kernel.org, linux-gpio@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 4/5] gpio: mvebu: don't limit pwm period/duty_cycle to UINT_MAX Date: Thu, 14 Jan 2021 20:57:36 +0200 Message-Id: X-Mailer: git-send-email 2.29.2 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org PWM on/off registers are limited to UINT_MAX. However the state period and duty_cycle fields are ns values of type u64. There is no reason to limit them to UINT_MAX. Reported-by: Uwe Kleine-König Reviewed-by: Uwe Kleine-König Signed-off-by: Baruch Siach --- drivers/gpio/gpio-mvebu.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index 8673ba77af5a..6b017854ce61 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -669,9 +669,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, regmap_read(mvpwm->regs, mvebu_pwmreg_blink_on_duration(mvpwm), &u); val = (unsigned long long) u * NSEC_PER_SEC; val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate); - if (val > UINT_MAX) - state->duty_cycle = UINT_MAX; - else if (val) + if (val) state->duty_cycle = val; else state->duty_cycle = 1; @@ -681,9 +679,7 @@ static void mvebu_pwm_get_state(struct pwm_chip *chip, val += (unsigned long long) u; /* period = on + off duration */ val *= NSEC_PER_SEC; val = DIV_ROUND_UP_ULL(val, mvpwm->clk_rate); - if (val > UINT_MAX) - state->period = UINT_MAX; - else if (val) + if (val) state->period = val; else state->period = 1; From patchwork Thu Jan 14 18:57:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Baruch Siach X-Patchwork-Id: 363136 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT 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 8F75EC43381 for ; Thu, 14 Jan 2021 18:59:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 665C223B31 for ; Thu, 14 Jan 2021 18:59:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726177AbhANS7N (ORCPT ); Thu, 14 Jan 2021 13:59:13 -0500 Received: from guitar.tcltek.co.il ([192.115.133.116]:47461 "EHLO mx.tkos.co.il" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725883AbhANS7M (ORCPT ); Thu, 14 Jan 2021 13:59:12 -0500 Received: from tarshish.tkos.co.il (unknown [10.0.8.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mx.tkos.co.il (Postfix) with ESMTPS id 3CB0E440932; Thu, 14 Jan 2021 20:57:56 +0200 (IST) From: Baruch Siach To: Thierry Reding , =?utf-8?q?Uwe_Kleine-K?= =?utf-8?b?w7ZuaWc=?= , Lee Jones , Linus Walleij , Bartosz Golaszewski Cc: Baruch Siach , Russell King , Andrew Lunn , Gregory Clement , Sebastian Hesselbarth , Thomas Petazzoni , Chris Packham , Sascha Hauer , Ralph Sennhauser , linux-pwm@vger.kernel.org, linux-gpio@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v3 5/5] gpio: mvebu: document zero pwm duty cycle limitation Date: Thu, 14 Jan 2021 20:57:37 +0200 Message-Id: <7c18dd67d3bf3e3ed9a8efa2edd33e8f29f09a7a.1610628807.git.baruch@tkos.co.il> X-Mailer: git-send-email 2.29.2 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Add a comment on why the code never sets on/off registers to zero. Reported-by: Uwe Kleine-König Analyzed-by: Russell King Signed-off-by: Baruch Siach --- drivers/gpio/gpio-mvebu.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index 6b017854ce61..09780944bef9 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -706,6 +706,10 @@ static int mvebu_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, do_div(val, NSEC_PER_SEC); if (val > UINT_MAX) return -EINVAL; + /* + * Zero on/off values don't work as expected. Experimentation shows + * that zero value is treated as 2^32. This behavior is not documented. + */ if (val) on = val; else