From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Levin Subject: [PATCH AUTOSEL 5.4 053/205] pwm: sun4i: Fix incorrect calculation of duty_cycle/period Date: Thu, 16 Jan 2020 11:40:28 -0500 Message-ID: <20200116164300.6705-53-sashal@kernel.org> References: <20200116164300.6705-1-sashal@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: <20200116164300.6705-1-sashal@kernel.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane-mx.org@lists.infradead.org To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ondrej Jirman , Sasha Levin , linux-pwm@vger.kernel.org, Thierry Reding , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , linux-arm-kernel@lists.infradead.org List-Id: linux-pwm@vger.kernel.org RnJvbTogT25kcmVqIEppcm1hbiA8bWVnb3VzQG1lZ291cy5jb20+CgpbIFVwc3RyZWFtIGNvbW1p dCA1MGNjN2UzZTRmMjZlM2JmNWVkNzRhOGQwNjExOTVjNGQyMTYxYjhiIF0KClNpbmNlIDUuNC1y YzEsIHB3bV9hcHBseV9zdGF0ZSBjYWxscyAtPmdldF9zdGF0ZSBhZnRlciAtPmFwcGx5CmlmIGF2 YWlsYWJsZSwgYW5kIHRoaXMgcmV2ZWFsZWQgYW4gaXNzdWUgd2l0aCBpbnRlZ2VyIHByZWNpc2lv bgp3aGVuIGNhbGN1bGF0aW5nIGR1dHlfY3ljbGUgYW5kIHBlcmlvZCBmb3IgdGhlIGN1cnJlbnRs eSBzZXQKc3RhdGUgaW4gLT5nZXRfc3RhdGUgY2FsbGJhY2suCgpUaGlzIGlzc3VlIG1hbmlmZXN0 ZWQgaW4gYnJva2VuIGJhY2tsaWdodCBvbiBzZXZlcmFsIEFsbHdpbm5lcgpiYXNlZCBkZXZpY2Vz LgoKUHJldmlvdXNseSB0aGlzIHdvcmtlZCwgYmVjYXVzZSAtPmFwcGx5IHVwZGF0ZWQgdGhlIHBh c3NlZCBzdGF0ZQpkaXJlY3RseS4KCkZpeGVzOiBkZWI5YzQ2MmY0ZTUzICgicHdtOiBzdW40aTog RG9uJ3QgdXBkYXRlIHRoZSBzdGF0ZSBmb3IgdGhlIGNhbGxlciBvZiBwd21fYXBwbHlfc3RhdGUi KQpTaWduZWQtb2ZmLWJ5OiBPbmRyZWogSmlybWFuIDxtZWdvdXNAbWVnb3VzLmNvbT4KQWNrZWQt Ynk6IFV3ZSBLbGVpbmUtS8O2bmlnIDx1LmtsZWluZS1rb2VuaWdAcGVuZ3V0cm9uaXguZGU+ClNp Z25lZC1vZmYtYnk6IFRoaWVycnkgUmVkaW5nIDx0aGllcnJ5LnJlZGluZ0BnbWFpbC5jb20+ClNp Z25lZC1vZmYtYnk6IFNhc2hhIExldmluIDxzYXNoYWxAa2VybmVsLm9yZz4KLS0tCiBkcml2ZXJz L3B3bS9wd20tc3VuNGkuYyB8IDQgKystLQogMSBmaWxlIGNoYW5nZWQsIDIgaW5zZXJ0aW9ucygr KSwgMiBkZWxldGlvbnMoLSkKCmRpZmYgLS1naXQgYS9kcml2ZXJzL3B3bS9wd20tc3VuNGkuYyBi L2RyaXZlcnMvcHdtL3B3bS1zdW40aS5jCmluZGV4IDZmNTg0MGExYTgyZC4uMDUyNzM3MjVhOWZm IDEwMDY0NAotLS0gYS9kcml2ZXJzL3B3bS9wd20tc3VuNGkuYworKysgYi9kcml2ZXJzL3B3bS9w d20tc3VuNGkuYwpAQCAtMTM3LDEwICsxMzcsMTAgQEAgc3RhdGljIHZvaWQgc3VuNGlfcHdtX2dl dF9zdGF0ZShzdHJ1Y3QgcHdtX2NoaXAgKmNoaXAsCiAKIAl2YWwgPSBzdW40aV9wd21fcmVhZGwo c3VuNGlfcHdtLCBQV01fQ0hfUFJEKHB3bS0+aHdwd20pKTsKIAotCXRtcCA9IHByZXNjYWxlciAq IE5TRUNfUEVSX1NFQyAqIFBXTV9SRUdfRFRZKHZhbCk7CisJdG1wID0gKHU2NClwcmVzY2FsZXIg KiBOU0VDX1BFUl9TRUMgKiBQV01fUkVHX0RUWSh2YWwpOwogCXN0YXRlLT5kdXR5X2N5Y2xlID0g RElWX1JPVU5EX0NMT1NFU1RfVUxMKHRtcCwgY2xrX3JhdGUpOwogCi0JdG1wID0gcHJlc2NhbGVy ICogTlNFQ19QRVJfU0VDICogUFdNX1JFR19QUkQodmFsKTsKKwl0bXAgPSAodTY0KXByZXNjYWxl ciAqIE5TRUNfUEVSX1NFQyAqIFBXTV9SRUdfUFJEKHZhbCk7CiAJc3RhdGUtPnBlcmlvZCA9IERJ Vl9ST1VORF9DTE9TRVNUX1VMTCh0bXAsIGNsa19yYXRlKTsKIH0KIAotLSAKMi4yMC4xCgoKX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KbGludXgtYXJtLWtl cm5lbCBtYWlsaW5nIGxpc3QKbGludXgtYXJtLWtlcm5lbEBsaXN0cy5pbmZyYWRlYWQub3JnCmh0 dHA6Ly9saXN0cy5pbmZyYWRlYWQub3JnL21haWxtYW4vbGlzdGluZm8vbGludXgtYXJtLWtlcm5l bAo= 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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 121D8C33CB1 for ; 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Thu, 16 Jan 2020 16:47:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579193244; bh=TxwKOVFcE2pzmB8eSzLGTN684D6ahhL2WTGB0irJpMc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PzMZa/1uCMHSCpC8q61Q87mU/WI8XW++I8IRZK8R6OG6M/fjAnHH1DtNvJ7RhNO77 YUZCPYnFwehTxKJeHrLefpglJ9eVT9fn98CPCzcXf7p1qRaMX+YqCU314Eli8w3H/z /HNCLxLp8g8mIAeLtTBjpSYVdTPSFJ253T+i254I= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ondrej Jirman , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= , Thierry Reding , Sasha Levin , linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH AUTOSEL 5.4 053/205] pwm: sun4i: Fix incorrect calculation of duty_cycle/period Date: Thu, 16 Jan 2020 11:40:28 -0500 Message-Id: <20200116164300.6705-53-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200116164300.6705-1-sashal@kernel.org> References: <20200116164300.6705-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ondrej Jirman [ Upstream commit 50cc7e3e4f26e3bf5ed74a8d061195c4d2161b8b ] Since 5.4-rc1, pwm_apply_state calls ->get_state after ->apply if available, and this revealed an issue with integer precision when calculating duty_cycle and period for the currently set state in ->get_state callback. This issue manifested in broken backlight on several Allwinner based devices. Previously this worked, because ->apply updated the passed state directly. Fixes: deb9c462f4e53 ("pwm: sun4i: Don't update the state for the caller of pwm_apply_state") Signed-off-by: Ondrej Jirman Acked-by: Uwe Kleine-König Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin --- drivers/pwm/pwm-sun4i.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 6f5840a1a82d..05273725a9ff 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -137,10 +137,10 @@ static void sun4i_pwm_get_state(struct pwm_chip *chip, val = sun4i_pwm_readl(sun4i_pwm, PWM_CH_PRD(pwm->hwpwm)); - tmp = prescaler * NSEC_PER_SEC * PWM_REG_DTY(val); + tmp = (u64)prescaler * NSEC_PER_SEC * PWM_REG_DTY(val); state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate); - tmp = prescaler * NSEC_PER_SEC * PWM_REG_PRD(val); + tmp = (u64)prescaler * NSEC_PER_SEC * PWM_REG_PRD(val); state->period = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate); } -- 2.20.1