From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754964Ab2IFMtW (ORCPT ); Thu, 6 Sep 2012 08:49:22 -0400 Received: from metis.ext.pengutronix.de ([92.198.50.35]:40949 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754750Ab2IFMsv (ORCPT ); Thu, 6 Sep 2012 08:48:51 -0400 From: Sascha Hauer To: Cc: HACHIMI Samir , shawn.guo@linaro.org, thierry.reding@avionic-design.de, linux-kernel@vger.kernel.org, =?UTF-8?q?Beno=C3=AEt=20Th=C3=A9baudeau?= , kernel@pengutronix.de, Philipp Zabel , Sascha Hauer Subject: [PATCH 7/9] pwm i.MX: fix clock lookup Date: Thu, 6 Sep 2012 14:48:13 +0200 Message-Id: <1346935695-25179-8-git-send-email-s.hauer@pengutronix.de> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1346935695-25179-1-git-send-email-s.hauer@pengutronix.de> References: <1346935695-25179-1-git-send-email-s.hauer@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:6f8:1178:2:21e:67ff:fe11:9c5c X-SA-Exim-Mail-From: sha@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Philipp Zabel The i.MX pwm core has two clocks: The ipg clock and the ipg highfreq (peripheral) clock. The ipg clock has to be enabled for this hardware to work. The actual pwm output can either be driven by the ipg clock or the ipg highfreq. The ipg highfreq has the advantage that it runs even when the SoC is in low power modes. This patch requests both clocks and enables the ipg clock for accessing registers and the peripheral clock to actually turn on the pwm. Signed-off-by: Philipp Zabel Signed-off-by: Sascha Hauer Reviewed-by: Shawn Guo Reviewed-by: Benoît Thébaudeau --- drivers/pwm/pwm-imx.c | 35 +++++++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 8 deletions(-) diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c index ea4ab2c..d45d44f 100644 --- a/drivers/pwm/pwm-imx.c +++ b/drivers/pwm/pwm-imx.c @@ -40,7 +40,8 @@ #define MX3_PWMCR_EN (1 << 0) struct imx_chip { - struct clk *clk; + struct clk *clk_per; + struct clk *clk_ipg; int enabled; void __iomem *mmio_base; @@ -105,7 +106,7 @@ static int imx_pwm_config_v2(struct pwm_chip *chip, unsigned long period_cycles, duty_cycles, prescale; u32 cr; - c = clk_get_rate(imx->clk); + c = clk_get_rate(imx->clk_per); c = c * period_ns; do_div(c, 1000000000); period_cycles = c; @@ -160,8 +161,17 @@ static int imx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns) { struct imx_chip *imx = to_imx_chip(chip); + int ret; + + ret = clk_prepare_enable(imx->clk_ipg); + if (ret) + return ret; - return imx->config(chip, pwm, duty_ns, period_ns); + ret = imx->config(chip, pwm, duty_ns, period_ns); + + clk_disable_unprepare(imx->clk_ipg); + + return ret; } static int imx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) @@ -169,7 +179,7 @@ static int imx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) struct imx_chip *imx = to_imx_chip(chip); int ret; - ret = clk_prepare_enable(imx->clk); + ret = clk_prepare_enable(imx->clk_per); if (ret) return ret; @@ -186,7 +196,7 @@ static void imx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) imx->set_enable(chip, false); - clk_disable_unprepare(imx->clk); + clk_disable_unprepare(imx->clk_per); imx->enabled = 0; } @@ -238,10 +248,19 @@ static int __devinit imx_pwm_probe(struct platform_device *pdev) return -ENOMEM; } - imx->clk = devm_clk_get(&pdev->dev, "pwm"); + imx->clk_per = devm_clk_get(&pdev->dev, "per"); + if (IS_ERR(imx->clk_per)) { + dev_err(&pdev->dev, "getting per clock failed with %ld\n", + PTR_ERR(imx->clk_per)); + return PTR_ERR(imx->clk_per); + } - if (IS_ERR(imx->clk)) - return PTR_ERR(imx->clk); + imx->clk_ipg = devm_clk_get(&pdev->dev, "ipg"); + if (IS_ERR(imx->clk_ipg)) { + dev_err(&pdev->dev, "getting ipg clock failed with %ld\n", + PTR_ERR(imx->clk_ipg)); + return PTR_ERR(imx->clk_ipg); + } imx->chip.ops = &imx_pwm_ops; imx->chip.dev = &pdev->dev; -- 1.7.10.4