@@ -38,6 +38,7 @@
#define MX3_PWMCR_DOZEEN (1 << 24)
#define MX3_PWMCR_WAITEN (1 << 23)
#define MX3_PWMCR_DBGEN (1 << 22)
+#define MX3_PWMCR_POUTC (1 << 18)
#define MX3_PWMCR_CLKSRC_IPG_HIGH (2 << 16)
#define MX3_PWMCR_CLKSRC_IPG (1 << 16)
#define MX3_PWMCR_SWR (1 << 3)
@@ -179,6 +180,9 @@ 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 +200,11 @@ 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 +248,49 @@ 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 +312,8 @@ static int imx_pwm_probe(struct platform_device *pdev)
if (!of_id)
return -ENODEV;
+ data = of_id->data;
+
imx = devm_kzalloc(&pdev->dev, sizeof(*imx), GFP_KERNEL);
if (imx == NULL)
return -ENOMEM;
@@ -299,18 +332,22 @@ 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;
imx->chip.can_sleep = true;
+ if (data->pwm_ops->set_polarity) {
+ dev_dbg(&pdev->dev, "PWM supports output inversion\n");
+ imx->chip.of_xlate = of_pwm_xlate_with_flags;
+ imx->chip.of_pwm_n_cells = 3;
+ }
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
imx->mmio_base = devm_ioremap_resource(&pdev->dev, r);
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;
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 Waßmann <LW@KARO-electronics.de> --- drivers/pwm/pwm-imx.c | 43 ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 40 insertions(+), 3 deletions(-)