From mboxrd@z Thu Jan 1 00:00:00 1970 From: LW@KARO-electronics.de (=?UTF-8?q?Lothar=20Wa=C3=9Fmann?=) Date: Tue, 7 Oct 2014 15:55:34 +0200 Subject: [PATCHv5 3/3] pwm: imx: support output polarity inversion In-Reply-To: <1412690134-13712-1-git-send-email-LW@KARO-electronics.de> References: <1412690134-13712-1-git-send-email-LW@KARO-electronics.de> Message-ID: <1412690134-13712-4-git-send-email-LW@KARO-electronics.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The i.MX pwm unit on i.MX27 and newer SoCs provides a configurable output polarity. This patch adds support to utilize this feature where available. Signed-off-by: Lothar Wa?mann Acked-by: Shawn Guo Reviewed-by: Sascha Hauer --- drivers/pwm/pwm-imx.c | 39 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 36 insertions(+), 3 deletions(-) diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c index f8b5f10..57aac836 100644 --- a/drivers/pwm/pwm-imx.c +++ b/drivers/pwm/pwm-imx.c @@ -179,6 +179,9 @@ static int imx_pwm_config_v2(struct pwm_chip *chip, if (enable) cr |= MX3_PWMCR_EN; + if (pwm->polarity == PWM_POLARITY_INVERSED) + cr |= MX3_PWMCR_POUTC; + writel(cr, imx->mmio_base + MX3_PWMCR); return 0; @@ -196,6 +199,11 @@ static void imx_pwm_set_enable_v2(struct pwm_chip *chip, bool enable) else val &= ~MX3_PWMCR_EN; + if (chip->pwms[0].polarity == PWM_POLARITY_INVERSED) + val |= MX3_PWMCR_POUTC; + else + val &= ~MX3_PWMCR_POUTC; + writel(val, imx->mmio_base + MX3_PWMCR); } @@ -239,27 +247,49 @@ static void imx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) clk_disable_unprepare(imx->clk_per); } -static struct pwm_ops imx_pwm_ops = { +static int imx_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct imx_chip *imx = to_imx_chip(chip); + + dev_dbg(imx->chip.dev, "%s: polarity set to %s\n", __func__, + polarity == PWM_POLARITY_INVERSED ? "inverted" : "normal"); + + return 0; +} + +static struct pwm_ops imx_pwm_ops_v1 = { .enable = imx_pwm_enable, .disable = imx_pwm_disable, .config = imx_pwm_config, .owner = THIS_MODULE, }; +static struct pwm_ops imx_pwm_ops_v2 = { + .enable = imx_pwm_enable, + .disable = imx_pwm_disable, + .set_polarity = imx_pwm_set_polarity, + .config = imx_pwm_config, + .owner = THIS_MODULE, +}; + struct imx_pwm_data { int (*config)(struct pwm_chip *chip, struct pwm_device *pwm, int duty_ns, int period_ns); void (*set_enable)(struct pwm_chip *chip, bool enable); + struct pwm_ops *pwm_ops; }; static struct imx_pwm_data imx_pwm_data_v1 = { .config = imx_pwm_config_v1, .set_enable = imx_pwm_set_enable_v1, + .pwm_ops = &imx_pwm_ops_v1, }; static struct imx_pwm_data imx_pwm_data_v2 = { .config = imx_pwm_config_v2, .set_enable = imx_pwm_set_enable_v2, + .pwm_ops = &imx_pwm_ops_v2, }; static const struct of_device_id imx_pwm_dt_ids[] = { @@ -281,6 +311,10 @@ static int imx_pwm_probe(struct platform_device *pdev) if (!of_id) return -ENODEV; + data = of_id->data; + if (data->pwm_ops->set_polarity) + dev_dbg(&pdev->dev, "PWM supports output inversion\n"); + imx = devm_kzalloc(&pdev->dev, sizeof(*imx), GFP_KERNEL); if (imx == NULL) return -ENOMEM; @@ -299,7 +333,7 @@ static int imx_pwm_probe(struct platform_device *pdev) return PTR_ERR(imx->clk_ipg); } - imx->chip.ops = &imx_pwm_ops; + imx->chip.ops = data->pwm_ops; imx->chip.dev = &pdev->dev; imx->chip.base = -1; imx->chip.npwm = 1; @@ -310,7 +344,6 @@ static int imx_pwm_probe(struct platform_device *pdev) if (IS_ERR(imx->mmio_base)) return PTR_ERR(imx->mmio_base); - data = of_id->data; imx->config = data->config; imx->set_enable = data->set_enable; -- 1.7.10.4