From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752902AbcDVKSj (ORCPT ); Fri, 22 Apr 2016 06:18:39 -0400 Received: from mail-wm0-f54.google.com ([74.125.82.54]:32961 "EHLO mail-wm0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752716AbcDVKSg (ORCPT ); Fri, 22 Apr 2016 06:18:36 -0400 From: Lee Jones To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: kernel@stlinux.com, maxime.coquelin@st.com, linux-pwm@vger.kernel.org, thierry.reding@gmail.com, ajitpal.singh@st.com, Lee Jones Subject: [[PATCH v2] 09/11] pwm: sti: Add support for PWM Capture IRQs Date: Fri, 22 Apr 2016 11:18:13 +0100 Message-Id: <1461320295-20414-10-git-send-email-lee.jones@linaro.org> X-Mailer: git-send-email 2.8.0 In-Reply-To: <1461320295-20414-1-git-send-email-lee.jones@linaro.org> References: <1461320295-20414-1-git-send-email-lee.jones@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Here we're requesting the PWM Capture IRQ and supplying the handler which will be called in the event of an IRQ fire to handle it. Signed-off-by: Lee Jones --- drivers/pwm/pwm-sti.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 91 insertions(+), 1 deletion(-) diff --git a/drivers/pwm/pwm-sti.c b/drivers/pwm/pwm-sti.c index 9d597bb..2230afb 100644 --- a/drivers/pwm/pwm-sti.c +++ b/drivers/pwm/pwm-sti.c @@ -91,7 +91,9 @@ struct sti_pwm_chip { struct regmap_field *prescale_low; struct regmap_field *prescale_high; struct regmap_field *pwm_out_en; + struct regmap_field *pwm_cpt_en; struct regmap_field *pwm_cpt_int_en; + struct regmap_field *pwm_cpt_int_stat; struct pwm_chip chip; struct pwm_device *cur; unsigned long configured; @@ -311,6 +313,76 @@ static const struct pwm_ops sti_pwm_ops = { .owner = THIS_MODULE, }; +static irqreturn_t sti_pwm_interrupt(int irq, void *data) +{ + struct sti_pwm_chip *pc = data; + struct device *dev = pc->dev; + struct sti_cpt_ddata *ddata; + int devicenum; + unsigned int cpt_int_stat; + unsigned int reg; + int ret = IRQ_NONE; + + ret = regmap_field_read(pc->pwm_cpt_int_stat, &cpt_int_stat); + if (ret) + return ret; + + while (cpt_int_stat) { + devicenum = ffs(cpt_int_stat) - 1; + + ddata = pwm_get_chip_data(&pc->chip.pwms[devicenum]); + + /* + * Capture input: + * _______ _______ + * | | | | + * __| |_________________| |________ + * ^0 ^1 ^2 + * + * Capture start by the first available rising edge + * When a capture event occurs, capture value (CPT_VALx) + * is stored, index incremented, capture edge changed. + * + * After the capture, if the index > 1, we have collected + * the necessary data so we signal the thread waiting for it + * and disable the capture by setting capture edge to none + * + */ + + regmap_read(pc->regmap, + PWM_CPT_VAL(devicenum), + &ddata->snapshot[ddata->index]); + + switch (ddata->index) { + case 0: + case 1: + regmap_read(pc->regmap, PWM_CPT_EDGE(devicenum), ®); + reg ^= PWM_CPT_EDGE_MASK; + regmap_write(pc->regmap, PWM_CPT_EDGE(devicenum), reg); + + ddata->index++; + break; + case 2: + regmap_write(pc->regmap, + PWM_CPT_EDGE(devicenum), + CPT_EDGE_DISABLED); + wake_up(&ddata->wait); + break; + default: + dev_err(dev, "Internal error\n"); + } + + cpt_int_stat &= ~BIT_MASK(devicenum); + + ret = IRQ_HANDLED; + } + + /* Just ACK everything */ + regmap_write(pc->regmap, PWM_INT_ACK, PWM_INT_ACK_MASK); + + return ret; +} + static int sti_pwm_probe_dt(struct sti_pwm_chip *pc) { struct device *dev = pc->dev; @@ -351,6 +423,11 @@ static int sti_pwm_probe_dt(struct sti_pwm_chip *pc) if (IS_ERR(pc->pwm_cpt_int_en)) return PTR_ERR(pc->pwm_cpt_int_en); + pc->pwm_cpt_int_stat = devm_regmap_field_alloc(dev, pc->regmap, + reg_fields[PWM_CPT_INT_STAT]); + if (PTR_ERR_OR_ZERO(pc->pwm_cpt_int_stat)) + return PTR_ERR(pc->pwm_cpt_int_stat); + return 0; } @@ -367,7 +444,7 @@ static int sti_pwm_probe(struct platform_device *pdev) struct sti_pwm_chip *pc; struct resource *res; unsigned int devnum; - int ret; + int irq, ret; pc = devm_kzalloc(dev, sizeof(*pc), GFP_KERNEL); if (!pc) @@ -388,6 +465,19 @@ static int sti_pwm_probe(struct platform_device *pdev) if (IS_ERR(pc->regmap)) return PTR_ERR(pc->regmap); + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "Failed to obtain IRQ\n"); + return irq; + } + + ret = devm_request_irq(&pdev->dev, irq, sti_pwm_interrupt, + 0, pdev->name, pc); + if (ret < 0) { + dev_err(&pdev->dev, "Failed to request IRQ\n"); + return ret; + } + /* * Setup PWM data with default values: some values could be replaced * with specific ones provided from Device Tree. -- 2.8.0