Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754091AbcJ0Gb0 (ORCPT ); Thu, 27 Oct 2016 02:31:26 -0400 Received: from 8.mo4.mail-out.ovh.net ([188.165.33.112]:51341 "EHLO 8.mo4.mail-out.ovh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751731AbcJ0GbZ (ORCPT ); Thu, 27 Oct 2016 02:31:25 -0400 X-Greylist: delayed 9296 seconds by postgrey-1.27 at vger.kernel.org; Thu, 27 Oct 2016 02:31:25 EDT From: Lukasz Majewski To: Thierry Reding , Stefan Agner , Boris Brezillon Cc: linux-pwm@vger.kernel.org, linux-kernel@vger.kernel.org, Fabio Estevam , Fabio Estevam , Lothar Wassmann , Bhuvanchandra DV , kernel@pengutronix.de, Lukasz Majewski Subject: [PATCH v2 06/10] pwm: imx: Provide atomic PWM support for i.MX PWMv2 Date: Thu, 27 Oct 2016 08:29:42 +0200 Message-Id: <1477549785-4972-7-git-send-email-l.majewski@majess.pl> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1477549785-4972-1-git-send-email-l.majewski@majess.pl> References: <1477549785-4972-1-git-send-email-l.majewski@majess.pl> X-Ovh-Tracer-Id: 11473764477786571397 X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeelvddrjedtgdduudduucetufdoteggodetrfdotffvucfrrhhofhhilhgvmecuqfggjfdpvefjgfevmfevgfenuceurghilhhouhhtmecufedttdenucesvcftvggtihhpihgvnhhtshculddquddttddm Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2852 Lines: 109 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 v2: - None --- drivers/pwm/pwm-imx.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c index f7c7534..6b7d2f1 100644 --- a/drivers/pwm/pwm-imx.c +++ b/drivers/pwm/pwm-imx.c @@ -174,6 +174,81 @@ 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; + + ret = clk_prepare_enable(imx->clk_ipg); + if (ret) + return 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); + + clk_disable_unprepare(imx->clk_ipg); + + return 0; +} + static int imx_pwm_config_v2(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { @@ -297,6 +372,7 @@ 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