[PATCHv4 0/4] pwm: imx: support output polarity inversion

[PATCHv4 0/4] pwm: imx: support output polarity inversion

[Lothar Waßmann]

This patch series adds support for polarity inversion to the pwm-imx
driver. The patches have been tested on i.MX6, i.MX53 and with the
ti-ehrpwm.c driver.

Changes wrt. v2:
- make the use of '#pwm-cells = <3>' optional, so that the change does
  not break existing DT blobs as suggested by Arnd Bergmann and Sascha
  Hauer.

Changes wrt. v3:
- implemented the approach suggested by Sascha Hauer 
- don't modify struct pwm_ops in the imx_pwm probe function

[PATCHv4 1/4] pwm: print error messages with pr_err() instead of pr_debug()

[Lothar Waßmann]

Make the messages that are printed in case of fatal errors actually
visible to the user without having to recompile the driver with
debugging enabled.

Signed-off-by: Lothar Wa?mann <LW@KARO-electronics.de>
---
 drivers/pwm/core.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 4b66bf0..7af0043 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -525,13 +525,13 @@ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id)
 	err = of_parse_phandle_with_args(np, "pwms", "#pwm-cells", index,
 					 &args);
 	if (err) {
-		pr_debug("%s(): can't parse \"pwms\" property\n", __func__);
+		pr_err("%s(): can't parse \"pwms\" property\n", __func__);
 		return ERR_PTR(err);
 	}
 
 	pc = of_node_to_pwmchip(args.np);
 	if (IS_ERR(pc)) {
-		pr_debug("%s(): PWM chip not found\n", __func__);
+		pr_err("%s(): PWM chip not found\n", __func__);
 		pwm = ERR_CAST(pc);
 		goto put;
 	}
-- 
1.7.10.4

[PATCHv4 2/4] pwm: make the PWM_POLARITY flag in DTB optional

[Lothar Waßmann]

Change the pwm chip driver registration, so that a chip driver that
supports polarity inversion can still be used with DTBs that don't
provide the 'PWM_POLARITY' flag.

This is done to provide polarity inversion support for the pwm-imx
driver without having to modify all existing DTS files.

Signed-off-by: Lothar Wa?mann <LW@KARO-electronics.de>
---
 drivers/pwm/core.c            |   18 ++++++------------
 drivers/pwm/pwm-atmel-tcb.c   |    1 -
 drivers/pwm/pwm-atmel.c       |    4 +---
 drivers/pwm/pwm-pxa.c         |    5 ++---
 drivers/pwm/pwm-renesas-tpu.c |    1 -
 drivers/pwm/pwm-samsung.c     |    1 -
 drivers/pwm/pwm-tiecap.c      |    1 -
 drivers/pwm/pwm-tiehrpwm.c    |    1 -
 drivers/pwm/pwm-vt8500.c      |    1 -
 include/linux/pwm.h           |    1 -
 10 files changed, 9 insertions(+), 25 deletions(-)

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 7af0043..ab0fc5a 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -136,7 +136,7 @@ of_pwm_xlate_with_flags(struct pwm_chip *pc, const struct of_phandle_args *args)
 {
 	struct pwm_device *pwm;
 
-	if (pc->of_pwm_n_cells < 3)
+	if (args->args_count != 3)
 		return ERR_PTR(-EINVAL);
 
 	if (args->args[0] >= pc->npwm)
@@ -162,12 +162,15 @@ of_pwm_simple_xlate(struct pwm_chip *pc, const struct of_phandle_args *args)
 {
 	struct pwm_device *pwm;
 
-	if (pc->of_pwm_n_cells < 2)
+	if (args->args_count < 2)
 		return ERR_PTR(-EINVAL);
 
 	if (args->args[0] >= pc->npwm)
 		return ERR_PTR(-EINVAL);
 
+	if (args->args_count > 2)
+		return of_pwm_xlate_with_flags(pc, args);
+
 	pwm = pwm_request_from_chip(pc, args->args[0], NULL);
 	if (IS_ERR(pwm))
 		return pwm;
@@ -182,10 +185,8 @@ static void of_pwmchip_add(struct pwm_chip *chip)
 	if (!chip->dev || !chip->dev->of_node)
 		return;
 
-	if (!chip->of_xlate) {
+	if (!chip->of_xlate)
 		chip->of_xlate = of_pwm_simple_xlate;
-		chip->of_pwm_n_cells = 2;
-	}
 
 	of_node_get(chip->dev->of_node);
 }
@@ -536,13 +537,6 @@ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id)
 		goto put;
 	}
 
-	if (args.args_count != pc->of_pwm_n_cells) {
-		pr_debug("%s: wrong #pwm-cells for %s\n", np->full_name,
-			 args.np->full_name);
-		pwm = ERR_PTR(-EINVAL);
-		goto put;
-	}
-
 	pwm = pc->of_xlate(pc, &args);
 	if (IS_ERR(pwm))
 		goto put;
diff --git a/drivers/pwm/pwm-atmel-tcb.c b/drivers/pwm/pwm-atmel-tcb.c
index f3dcd02..55fabf8 100644
--- a/drivers/pwm/pwm-atmel-tcb.c
+++ b/drivers/pwm/pwm-atmel-tcb.c
@@ -395,7 +395,6 @@ static int atmel_tcb_pwm_probe(struct platform_device *pdev)
 	tcbpwm->chip.dev = &pdev->dev;
 	tcbpwm->chip.ops = &atmel_tcb_pwm_ops;
 	tcbpwm->chip.of_xlate = of_pwm_xlate_with_flags;
-	tcbpwm->chip.of_pwm_n_cells = 3;
 	tcbpwm->chip.base = -1;
 	tcbpwm->chip.npwm = NPWM;
 	tcbpwm->tc = tc;
diff --git a/drivers/pwm/pwm-atmel.c b/drivers/pwm/pwm-atmel.c
index 6e700a5..ae7c946 100644
--- a/drivers/pwm/pwm-atmel.c
+++ b/drivers/pwm/pwm-atmel.c
@@ -350,10 +350,8 @@ static int atmel_pwm_probe(struct platform_device *pdev)
 	atmel_pwm->chip.dev = &pdev->dev;
 	atmel_pwm->chip.ops = &atmel_pwm_ops;
 
-	if (pdev->dev.of_node) {
+	if (pdev->dev.of_node)
 		atmel_pwm->chip.of_xlate = of_pwm_xlate_with_flags;
-		atmel_pwm->chip.of_pwm_n_cells = 3;
-	}
 
 	atmel_pwm->chip.base = -1;
 	atmel_pwm->chip.npwm = 4;
diff --git a/drivers/pwm/pwm-pxa.c b/drivers/pwm/pwm-pxa.c
index 0b312ec..5656052 100644
--- a/drivers/pwm/pwm-pxa.c
+++ b/drivers/pwm/pwm-pxa.c
@@ -191,10 +191,9 @@ static int pwm_probe(struct platform_device *pdev)
 	pwm->chip.base = -1;
 	pwm->chip.npwm = (id->driver_data & HAS_SECONDARY_PWM) ? 2 : 1;
 
-	if (IS_ENABLED(CONFIG_OF)) {
+	if (IS_ENABLED(CONFIG_OF))
 		pwm->chip.of_xlate = pxa_pwm_of_xlate;
-		pwm->chip.of_pwm_n_cells = 1;
-	}
+
 
 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	pwm->mmio_base = devm_ioremap_resource(&pdev->dev, r);
diff --git a/drivers/pwm/pwm-renesas-tpu.c b/drivers/pwm/pwm-renesas-tpu.c
index 3b71b42..5271da3 100644
--- a/drivers/pwm/pwm-renesas-tpu.c
+++ b/drivers/pwm/pwm-renesas-tpu.c
@@ -419,7 +419,6 @@ static int tpu_probe(struct platform_device *pdev)
 	tpu->chip.dev = &pdev->dev;
 	tpu->chip.ops = &tpu_pwm_ops;
 	tpu->chip.of_xlate = of_pwm_xlate_with_flags;
-	tpu->chip.of_pwm_n_cells = 3;
 	tpu->chip.base = -1;
 	tpu->chip.npwm = TPU_CHANNEL_MAX;
 
diff --git a/drivers/pwm/pwm-samsung.c b/drivers/pwm/pwm-samsung.c
index ba6b650..317d7d1 100644
--- a/drivers/pwm/pwm-samsung.c
+++ b/drivers/pwm/pwm-samsung.c
@@ -484,7 +484,6 @@ static int pwm_samsung_probe(struct platform_device *pdev)
 			return ret;
 
 		chip->chip.of_xlate = of_pwm_xlate_with_flags;
-		chip->chip.of_pwm_n_cells = 3;
 	} else {
 		if (!pdev->dev.platform_data) {
 			dev_err(&pdev->dev, "no platform data specified\n");
diff --git a/drivers/pwm/pwm-tiecap.c b/drivers/pwm/pwm-tiecap.c
index 74efbe7..a8e8282 100644
--- a/drivers/pwm/pwm-tiecap.c
+++ b/drivers/pwm/pwm-tiecap.c
@@ -227,7 +227,6 @@ static int ecap_pwm_probe(struct platform_device *pdev)
 	pc->chip.dev = &pdev->dev;
 	pc->chip.ops = &ecap_pwm_ops;
 	pc->chip.of_xlate = of_pwm_xlate_with_flags;
-	pc->chip.of_pwm_n_cells = 3;
 	pc->chip.base = -1;
 	pc->chip.npwm = 1;
 
diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c
index cb75133..12a8ae4 100644
--- a/drivers/pwm/pwm-tiehrpwm.c
+++ b/drivers/pwm/pwm-tiehrpwm.c
@@ -458,7 +458,6 @@ static int ehrpwm_pwm_probe(struct platform_device *pdev)
 	pc->chip.dev = &pdev->dev;
 	pc->chip.ops = &ehrpwm_pwm_ops;
 	pc->chip.of_xlate = of_pwm_xlate_with_flags;
-	pc->chip.of_pwm_n_cells = 3;
 	pc->chip.base = -1;
 	pc->chip.npwm = NUM_PWM_CHANNEL;
 
diff --git a/drivers/pwm/pwm-vt8500.c b/drivers/pwm/pwm-vt8500.c
index 652e6b5..e04a3c0 100644
--- a/drivers/pwm/pwm-vt8500.c
+++ b/drivers/pwm/pwm-vt8500.c
@@ -217,7 +217,6 @@ static int vt8500_pwm_probe(struct platform_device *pdev)
 	chip->chip.dev = &pdev->dev;
 	chip->chip.ops = &vt8500_pwm_ops;
 	chip->chip.of_xlate = of_pwm_xlate_with_flags;
-	chip->chip.of_pwm_n_cells = 3;
 	chip->chip.base = -1;
 	chip->chip.npwm = VT8500_NR_PWMS;
 
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index e90628c..4cf1569 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -174,7 +174,6 @@ struct pwm_chip {
 
 	struct pwm_device *	(*of_xlate)(struct pwm_chip *pc,
 					    const struct of_phandle_args *args);
-	unsigned int		of_pwm_n_cells;
 	bool			can_sleep;
 };
 
-- 
1.7.10.4

[PATCHv4 3/4] pwm: imx: indentation cleanup

[Lothar Waßmann]

Signed-off-by: Lothar Wa?mann <LW@KARO-electronics.de>
---
 drivers/pwm/pwm-imx.c |   21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c
index 5449d91..f836635 100644
--- a/drivers/pwm/pwm-imx.c
+++ b/drivers/pwm/pwm-imx.c
@@ -25,20 +25,21 @@
 #define MX1_PWMS    0x04   /* PWM Sample Register */
 #define MX1_PWMP    0x08   /* PWM Period Register */
 
-#define MX1_PWMC_EN		(1 << 4)
+#define MX1_PWMC_EN			(1 << 4)
 
 /* i.MX27, i.MX31, i.MX35 share the same PWM function block: */
 
-#define MX3_PWMCR                 0x00    /* PWM Control Register */
-#define MX3_PWMSAR                0x0C    /* PWM Sample Register */
-#define MX3_PWMPR                 0x10    /* PWM Period Register */
-#define MX3_PWMCR_PRESCALER(x)    (((x - 1) & 0xFFF) << 4)
-#define MX3_PWMCR_DOZEEN                (1 << 24)
-#define MX3_PWMCR_WAITEN                (1 << 23)
+#define MX3_PWMCR			0x00	  /* PWM Control Register */
+#define MX3_PWMSAR			0x0C	  /* PWM Sample Register */
+#define MX3_PWMPR			0x10	  /* PWM Period Register */
+#define MX3_PWMCR_PRESCALER(x)		((((x) - 1) & 0xFFF) << 4)
+#define MX3_PWMCR_DOZEEN		(1 << 24)
+#define MX3_PWMCR_WAITEN		(1 << 23)
 #define MX3_PWMCR_DBGEN			(1 << 22)
-#define MX3_PWMCR_CLKSRC_IPG_HIGH (2 << 16)
-#define MX3_PWMCR_CLKSRC_IPG      (1 << 16)
-#define MX3_PWMCR_EN              (1 << 0)
+#define MX3_PWMCR_POUTC			(1 << 18)
+#define MX3_PWMCR_CLKSRC_IPG_HIGH	(2 << 16)
+#define MX3_PWMCR_CLKSRC_IPG		(1 << 16)
+#define MX3_PWMCR_EN			(1 << 0)
 
 struct imx_chip {
 	struct clk	*clk_per;
-- 
1.7.10.4

[PATCHv4 4/4] pwm: imx: support output polarity inversion

[Lothar Waßmann]

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 <LW@KARO-electronics.de>
---
 drivers/pwm/pwm-imx.c |   38 +++++++++++++++++++++++++++++++++++---
 1 file changed, 35 insertions(+), 3 deletions(-)

diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c
index f836635..585b0a8 100644
--- a/drivers/pwm/pwm-imx.c
+++ b/drivers/pwm/pwm-imx.c
@@ -138,6 +138,8 @@ static int imx_pwm_config_v2(struct pwm_chip *chip,
 
 	if (test_bit(PWMF_ENABLED, &pwm->flags))
 		cr |= MX3_PWMCR_EN;
+	if (pwm->polarity == PWM_POLARITY_INVERSED)
+		cr |= MX3_PWMCR_POUTC;
 
 	writel(cr, imx->mmio_base + MX3_PWMCR);
 
@@ -156,6 +158,11 @@ 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);
 }
 
@@ -199,27 +206,49 @@ 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[] = {
@@ -241,6 +270,10 @@ 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;
@@ -259,7 +292,7 @@ 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;
@@ -270,7 +303,6 @@ 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

[PATCHv4 0/4] pwm: imx: support output polarity inversion

[Lothar Waßmann]

Hi,

Lothar Wa?mann wrote:
> This patch series adds support for polarity inversion to the pwm-imx
> driver. The patches have been tested on i.MX6, i.MX53 and with the
> ti-ehrpwm.c driver.
> 
> Changes wrt. v2:
> - make the use of '#pwm-cells = <3>' optional, so that the change does
>   not break existing DT blobs as suggested by Arnd Bergmann and Sascha
>   Hauer.
> 
> Changes wrt. v3:
> - implemented the approach suggested by Sascha Hauer 
> - don't modify struct pwm_ops in the imx_pwm probe function
> 
> 
Any further comments?
Anyone taking care of these patches?


Lothar Wa?mann
-- 
___________________________________________________________

Ka-Ro electronics GmbH | Pascalstra?e 22 | D - 52076 Aachen
Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10
Gesch?ftsf?hrer: Matthias Kaussen
Handelsregistereintrag: Amtsgericht Aachen, HRB 4996

www.karo-electronics.de | info at karo-electronics.de
___________________________________________________________

[PATCHv4 4/4] pwm: imx: support output polarity inversion

[Shawn Guo]

On Wed, Aug 20, 2014 at 08:55:56AM +0200, Lothar Wa?mann wrote:
> 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 <LW@KARO-electronics.de>

Acked-by: Shawn Guo <shawn.guo@linaro.org>

[PATCHv4 0/4] pwm: imx: support output polarity inversion

[Lothar Waßmann]

Hi,

Lothar Wa?mann wrote:
> This patch series adds support for polarity inversion to the pwm-imx
> driver. The patches have been tested on i.MX6, i.MX53 and with the
> ti-ehrpwm.c driver.
> 
> Changes wrt. v2:
> - make the use of '#pwm-cells = <3>' optional, so that the change does
>   not break existing DT blobs as suggested by Arnd Bergmann and Sascha
>   Hauer.
> 
> Changes wrt. v3:
> - implemented the approach suggested by Sascha Hauer 
> - don't modify struct pwm_ops in the imx_pwm probe function
> 
> 
Ping?
It's now over a month without any reaction. What should I do with these
patches?


Lothar Wa?mann
-- 
___________________________________________________________

Ka-Ro electronics GmbH | Pascalstra?e 22 | D - 52076 Aachen
Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10
Gesch?ftsf?hrer: Matthias Kaussen
Handelsregistereintrag: Amtsgericht Aachen, HRB 4996

www.karo-electronics.de | info at karo-electronics.de
___________________________________________________________

[PATCHv4 0/4] pwm: imx: support output polarity inversion

[Sascha Hauer]

On Tue, Aug 26, 2014 at 09:24:09AM +0200, Lothar Wa?mann wrote:
> Hi,
> 
> Lothar Wa?mann wrote:
> > This patch series adds support for polarity inversion to the pwm-imx
> > driver. The patches have been tested on i.MX6, i.MX53 and with the
> > ti-ehrpwm.c driver.
> > 
> > Changes wrt. v2:
> > - make the use of '#pwm-cells = <3>' optional, so that the change does
> >   not break existing DT blobs as suggested by Arnd Bergmann and Sascha
> >   Hauer.
> > 
> > Changes wrt. v3:
> > - implemented the approach suggested by Sascha Hauer 
> > - don't modify struct pwm_ops in the imx_pwm probe function
> > 
> > 
> Any further comments?

No, except this one:

Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>

Sascha

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

[PATCHv4 0/4] pwm: imx: support output polarity inversion

[Lothar Waßmann]

This patch series adds support for polarity inversion to the pwm-imx
driver. The patches have been tested on i.MX6, i.MX53 and with the
ti-ehrpwm.c driver.

Changes wrt. v2:
- make the use of '#pwm-cells = <3>' optional, so that the change does
  not break existing DT blobs as suggested by Arnd Bergmann and Sascha
  Hauer.

Changes wrt. v3:
- implemented the approach suggested by Sascha Hauer 
- don't modify struct pwm_ops in the imx_pwm probe function