Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757837AbcJXPXx (ORCPT ); Mon, 24 Oct 2016 11:23:53 -0400 Received: from up.free-electrons.com ([163.172.77.33]:46773 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1756511AbcJXPXv (ORCPT ); Mon, 24 Oct 2016 11:23:51 -0400 Date: Mon, 24 Oct 2016 17:23:49 +0200 From: Boris Brezillon To: Lukasz Majewski Cc: Thierry Reding , Stefan Agner , linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org, Fabio Estevam , Fabio Estevam , Lothar Wassmann , Bhuvanchandra DV , kernel@pengutronix.de Subject: Re: [PATCH 3/6] pwm: imx: Move PWMv2 wait for fifo slot code to a separate function Message-ID: <20161024172349.496a7386@bbrezillon> In-Reply-To: <1477259146-19167-4-git-send-email-l.majewski@majess.pl> References: <1477259146-19167-1-git-send-email-l.majewski@majess.pl> <1477259146-19167-4-git-send-email-l.majewski@majess.pl> X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2857 Lines: 87 On Sun, 23 Oct 2016 23:45:43 +0200 Lukasz Majewski wrote: > The code, which waits for fifo slot, has been extracted from > imx_pwm_config_v2 function and moved to new one - imx_pwm_wait_fifo_slot(). > > This change reduces the overall size of imx_pwm_config_v2() and prepares > it for atomic PWM operation. > > Suggested-by: Stefan Agner > Suggested-by: Boris Brezillon > Signed-off-by: Lukasz Majewski Reviewed-by: Boris Brezillon > --- > drivers/pwm/pwm-imx.c | 42 +++++++++++++++++++++++++----------------- > 1 file changed, 25 insertions(+), 17 deletions(-) > > diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c > index fac5c93..f3577c5 100644 > --- a/drivers/pwm/pwm-imx.c > +++ b/drivers/pwm/pwm-imx.c > @@ -149,18 +149,36 @@ static void imx_pwm_sw_reset(struct pwm_chip *chip) > dev_warn(dev, "software reset timeout\n"); > } > > +static void imx_pwm_wait_fifo_slot(struct pwm_chip *chip, > + struct pwm_device *pwm) > +{ > + struct imx_chip *imx = to_imx_chip(chip); > + struct device *dev = chip->dev; > + unsigned int period_ms; > + int fifoav; > + u32 sr; > + > + sr = readl(imx->mmio_base + MX3_PWMSR); > + fifoav = sr & MX3_PWMSR_FIFOAV_MASK; > + if (fifoav == MX3_PWMSR_FIFOAV_4WORDS) { > + period_ms = DIV_ROUND_UP(pwm_get_period(pwm), > + NSEC_PER_MSEC); > + msleep(period_ms); > + > + sr = readl(imx->mmio_base + MX3_PWMSR); > + if (fifoav == (sr & MX3_PWMSR_FIFOAV_MASK)) > + dev_warn(dev, "there is no free FIFO slot\n"); > + } > +} > > static int imx_pwm_config_v2(struct pwm_chip *chip, > struct pwm_device *pwm, int duty_ns, int period_ns) > { > struct imx_chip *imx = to_imx_chip(chip); > - struct device *dev = chip->dev; > unsigned long long c; > unsigned long period_cycles, duty_cycles, prescale; > - unsigned int period_ms; > bool enable = pwm_is_enabled(pwm); > - int fifoav; > - u32 cr, sr; > + u32 cr; > > /* > * i.MX PWMv2 has a 4-word sample FIFO. > @@ -169,19 +187,9 @@ static int imx_pwm_config_v2(struct pwm_chip *chip, > * wait for a full PWM cycle to get a relinquished FIFO slot > * when the controller is enabled and the FIFO is fully loaded. > */ > - if (enable) { > - sr = readl(imx->mmio_base + MX3_PWMSR); > - fifoav = sr & MX3_PWMSR_FIFOAV_MASK; > - if (fifoav == MX3_PWMSR_FIFOAV_4WORDS) { > - period_ms = DIV_ROUND_UP(pwm_get_period(pwm), > - NSEC_PER_MSEC); > - msleep(period_ms); > - > - sr = readl(imx->mmio_base + MX3_PWMSR); > - if (fifoav == (sr & MX3_PWMSR_FIFOAV_MASK)) > - dev_warn(dev, "there is no free FIFO slot\n"); > - } > - } else > + if (enable) > + imx_pwm_wait_fifo_slot(chip, pwm); > + else > imx_pwm_sw_reset(chip); > > c = clk_get_rate(imx->clk_per);