Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755900AbcLZW55 (ORCPT ); Mon, 26 Dec 2016 17:57:57 -0500 Received: from 2.mo177.mail-out.ovh.net ([178.33.109.80]:55404 "EHLO 2.mo177.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755769AbcLZW5y (ORCPT ); Mon, 26 Dec 2016 17:57:54 -0500 From: Lukasz Majewski To: Thierry Reding , Sascha Hauer , Stefan Agner , linux-pwm@vger.kernel.org, Bhuvanchandra DV , linux-kernel@vger.kernel.org Cc: Fabio Estevam , Fabio Estevam , Boris Brezillon , Lothar Wassmann , kernel@pengutronix.de, Lukasz Majewski Subject: [PATCH v3 RESEND 07/11] pwm: imx: Provide atomic PWM support for i.MX PWMv2 Date: Mon, 26 Dec 2016 23:55:57 +0100 Message-Id: <1482792961-12702-8-git-send-email-l.majewski@majess.pl> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1482792961-12702-1-git-send-email-l.majewski@majess.pl> References: <1477259146-19167-1-git-send-email-l.majewski@majess.pl> <1482792961-12702-1-git-send-email-l.majewski@majess.pl> X-Ovh-Tracer-Id: 11561021721696912005 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeelfedrledvgdduieekucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuqfggjfdpvefjgfevmfevgfenuceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddm Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2802 Lines: 106 This commit provides apply() callback implementation for i.MX's PWMv2. Suggested-by: Stefan Agner Suggested-by: Boris Brezillon Signed-off-by: Lukasz Majewski Reviewed-by: Boris Brezillon --- Changes for v3: - Remove ipg clock enable/disable functions Changes for v2: - None --- drivers/pwm/pwm-imx.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c index ebe9b0c..cd53c05 100644 --- a/drivers/pwm/pwm-imx.c +++ b/drivers/pwm/pwm-imx.c @@ -159,6 +159,75 @@ static void imx_pwm_wait_fifo_slot(struct pwm_chip *chip, } } +static int imx_pwm_apply_v2(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + unsigned long period_cycles, duty_cycles, prescale; + struct imx_chip *imx = to_imx_chip(chip); + struct pwm_state cstate; + unsigned long long c; + u32 cr = 0; + int ret; + + pwm_get_state(pwm, &cstate); + + c = clk_get_rate(imx->clk_per); + c *= state->period; + + do_div(c, 1000000000); + period_cycles = c; + + prescale = period_cycles / 0x10000 + 1; + + period_cycles /= prescale; + c = (unsigned long long)period_cycles * state->duty_cycle; + do_div(c, state->period); + duty_cycles = c; + + /* + * according to imx pwm RM, the real period value should be + * PERIOD value in PWMPR plus 2. + */ + if (period_cycles > 2) + period_cycles -= 2; + else + period_cycles = 0; + + /* Enable the clock if the PWM is being enabled. */ + if (state->enabled && !cstate.enabled) { + ret = clk_prepare_enable(imx->clk_per); + if (ret) + return ret; + } + + /* + * Wait for a free FIFO slot if the PWM is already enabled, and flush + * the FIFO if the PWM was disabled and is about to be enabled. + */ + if (cstate.enabled) + imx_pwm_wait_fifo_slot(chip, pwm); + else if (state->enabled) + imx_pwm_sw_reset(chip); + + writel(duty_cycles, imx->mmio_base + MX3_PWMSAR); + writel(period_cycles, imx->mmio_base + MX3_PWMPR); + + cr |= MX3_PWMCR_PRESCALER(prescale) | + MX3_PWMCR_DOZEEN | MX3_PWMCR_WAITEN | + MX3_PWMCR_DBGEN | MX3_PWMCR_CLKSRC_IPG_HIGH; + + if (state->enabled) + cr |= MX3_PWMCR_EN; + + writel(cr, imx->mmio_base + MX3_PWMCR); + + /* Disable the clock if the PWM is being disabled. */ + if (!state->enabled && cstate.enabled) + clk_disable_unprepare(imx->clk_per); + + return 0; +} + static int imx_pwm_config_v2(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { @@ -273,6 +342,7 @@ static struct pwm_ops imx_pwm_ops_v2 = { .enable = imx_pwm_enable, .disable = imx_pwm_disable, .config = imx_pwm_config, + .apply = imx_pwm_apply_v2, .owner = THIS_MODULE, }; -- 2.1.4