diff mbox

[v4,06/11] pwm: pwm-tiehrpwm: Add device-tree binding support for EHRPWM driver

Message ID 1353503469-18634-7-git-send-email-avinashphilip@ti.com (mailing list archive)
State New, archived
Headers show

Commit Message

avinash philip Nov. 21, 2012, 1:11 p.m. UTC
This patch
1. Add support for device-tree binding for EHRWPM driver.
2. Set size of pwm-cells set to 3 to support PWM channel number, PWM
   period & polarity configuration from device tree.
3. Add enable/disable clock gating in PWM subsystem common config space.
4. When here set .owner member in platform_driver structure to
   THIS_MODULE.

Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
---
Changes since v3:
	- Replace pwmss.h with pwm-tipwmss.h

Changes since v2:
	- Add of_pwm_xlate_with_flags function support

Changes since v1:
	- Add separate patch for pinctrl support
	- Add conditional check for PWM subsystem clock enable.
	- Combined with HWMOD changes & DT bindings.
	- Remove the custom of_xlate support.

:000000 100644 0000000... 4fc7079... A	Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
:100644 100644 d3c1dff... 34f9378... M	drivers/pwm/pwm-tiehrpwm.c
 .../devicetree/bindings/pwm/pwm-tiehrpwm.txt       |   23 ++++++++++
 drivers/pwm/pwm-tiehrpwm.c                         |   45 +++++++++++++++++++-
 2 files changed, 66 insertions(+), 2 deletions(-)

Comments

Thierry Reding Nov. 22, 2012, 9:03 p.m. UTC | #1
On Wed, Nov 21, 2012 at 06:41:03PM +0530, Philip, Avinash wrote:
[...]
> +static const struct of_device_id ehrpwm_of_match[] = {
> +	{
> +		.compatible	= "ti,am33xx-ehrpwm",
> +	},

Same comment as for patch 4.

> @@ -437,16 +451,41 @@ static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev)
>  		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
>  		return ret;
>  	}
> -

I think this blank line actually improves readability so it can stay in.

Thierry
avinash philip Nov. 23, 2012, 10:35 a.m. UTC | #2
On Fri, Nov 23, 2012 at 02:33:47, Thierry Reding wrote:
> On Wed, Nov 21, 2012 at 06:41:03PM +0530, Philip, Avinash wrote:
> [...]
> > +static const struct of_device_id ehrpwm_of_match[] = {
> > +	{
> > +		.compatible	= "ti,am33xx-ehrpwm",
> > +	},
> 
> Same comment as for patch 4.

Ok I will correct it.

> 
> > @@ -437,16 +451,41 @@ static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev)
> >  		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
> >  		return ret;
> >  	}
> > -
> 
> I think this blank line actually improves readability so it can stay in.

I will add.

Thanks
Avinash

> 
> Thierry
> 

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diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt b/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
new file mode 100644
index 0000000..4fc7079
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
@@ -0,0 +1,23 @@ 
+TI SOC EHRPWM based PWM controller
+
+Required properties:
+- compatible : Must be "ti,am33xx-ehrpwm"
+- #pwm-cells: Should be 3. Number of cells being used to specify PWM property.
+  First cell specifies the per-chip index of the PWM to use, the second
+  cell is the period in nanoseconds and bit 0 in the third cell is used to
+  encode the polarity of PWM output. Set bit 0 of the third in PWM specifier
+  to 1 for inverse polarity & set to 0 for normal polarity.
+- reg: physical base address and size of the registers map.
+
+Optional properties:
+- ti,hwmods: Name of the hwmod associated to the EHRPWM:
+  "ehrpwm<x>", <x> being the 0-based instance number from the HW spec
+
+Example:
+
+ehrpwm0: ehrpwm@0 {
+	compatible = "ti,am33xx-ehrpwm";
+	#pwm-cells = <3>;
+	reg = <0x48300200 0x100>;
+	ti,hwmods = "ehrpwm0";
+};
diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c
index d3c1dff..34f9378 100644
--- a/drivers/pwm/pwm-tiehrpwm.c
+++ b/drivers/pwm/pwm-tiehrpwm.c
@@ -25,6 +25,9 @@ 
 #include <linux/err.h>
 #include <linux/clk.h>
 #include <linux/pm_runtime.h>
+#include <linux/of_device.h>
+
+#include "pwm-tipwmss.h"
 
 /* EHRPWM registers and bits definitions */
 
@@ -392,12 +395,21 @@  static const struct pwm_ops ehrpwm_pwm_ops = {
 	.owner		= THIS_MODULE,
 };
 
+static const struct of_device_id ehrpwm_of_match[] = {
+	{
+		.compatible	= "ti,am33xx-ehrpwm",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
+
 static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev)
 {
 	int ret;
 	struct resource *r;
 	struct clk *clk;
 	struct ehrpwm_pwm_chip *pc;
+	u16 status;
 
 	pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
 	if (!pc) {
@@ -419,6 +431,8 @@  static int __devinit 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;
 
@@ -437,16 +451,41 @@  static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
 		return ret;
 	}
-
 	pm_runtime_enable(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+
+	status = pwmss_submodule_state_change(pdev->dev.parent,
+			PWMSS_EPWMCLK_EN);
+	if (!(status & PWMSS_EPWMCLK_EN_ACK)) {
+		dev_err(&pdev->dev, "PWMSS config space clock enable failed\n");
+		ret = -EINVAL;
+		goto pwmss_clk_failure;
+	}
+
+	pm_runtime_put_sync(&pdev->dev);
+
 	platform_set_drvdata(pdev, pc);
 	return 0;
+
+pwmss_clk_failure:
+	pm_runtime_put_sync(&pdev->dev);
+	pm_runtime_disable(&pdev->dev);
+	pwmchip_remove(&pc->chip);
+	return ret;
 }
 
 static int __devexit ehrpwm_pwm_remove(struct platform_device *pdev)
 {
 	struct ehrpwm_pwm_chip *pc = platform_get_drvdata(pdev);
 
+	pm_runtime_get_sync(&pdev->dev);
+	/*
+	 * Due to hardware misbehaviour, acknowledge of the stop_req
+	 * is missing. Hence checking of the status bit skipped.
+	 */
+	pwmss_submodule_state_change(pdev->dev.parent, PWMSS_EPWMCLK_STOP_REQ);
+	pm_runtime_put_sync(&pdev->dev);
+
 	pm_runtime_put_sync(&pdev->dev);
 	pm_runtime_disable(&pdev->dev);
 	return pwmchip_remove(&pc->chip);
@@ -454,7 +493,9 @@  static int __devexit ehrpwm_pwm_remove(struct platform_device *pdev)
 
 static struct platform_driver ehrpwm_pwm_driver = {
 	.driver = {
-		.name = "ehrpwm",
+		.name	= "ehrpwm",
+		.owner	= THIS_MODULE,
+		.of_match_table = ehrpwm_of_match,
 	},
 	.probe = ehrpwm_pwm_probe,
 	.remove = __devexit_p(ehrpwm_pwm_remove),