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Subject[PATCH 5/8] pwm: pwm-tiehrpwm: Add device-tree binding support for EHRPWM driver
Date
Add support for device-tree binding for EHRWPM driver.
Also size of #pwm-cells set to 3 to support PWM channel number, PWM
period & polarity configuration from device tree.
Also enable clock gating in PWM subsystem common config space.
Also 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>
---
Second version
- Combined with HWMOD changes & DT bindings.
- Remove the custom of_xlate support.

:000000 100644 0000000... aa2ed0a... A Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
:100644 100644 d3c1dff... 1e63652... M drivers/pwm/pwm-tiehrpwm.c
.../devicetree/bindings/pwm/pwm-tiehrpwm.txt | 25 +++++++++++++
drivers/pwm/pwm-tiehrpwm.c | 37 ++++++++++++++++++-
2 files changed, 60 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt b/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
new file mode 100644
index 0000000..aa2ed0a
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
@@ -0,0 +1,25 @@
+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 cycle in nanoseconds and bit 0 in the third cell is
+ used to encode the polarity of PWM output.
+- 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
+- tbclkgating: platforms require tbclk gating from control module
+ should populate
+
+Example:
+
+ehrpwm0: ehrpwm@0 {
+ compatible = "ti,am33xx-ehrpwm";
+ #pwm-cells = <3>;
+ reg = <0x48300200 0x100>;
+ ti,hwmods = "ehrpwm0";
+ tbclkgating;
+};
diff --git a/drivers/pwm/pwm-tiehrpwm.c b/drivers/pwm/pwm-tiehrpwm.c
index d3c1dff..1e63652 100644
--- a/drivers/pwm/pwm-tiehrpwm.c
+++ b/drivers/pwm/pwm-tiehrpwm.c
@@ -25,6 +25,10 @@
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/pm_runtime.h>
+#include <linux/of_device.h>
+#include <linux/pinctrl/consumer.h>
+
+#include "tipwmss.h"

/* EHRPWM registers and bits definitions */

@@ -107,6 +111,10 @@
#define AQCSFRC_CSFA_FRCHIGH BIT(1)
#define AQCSFRC_CSFA_DISSWFRC (BIT(1) | BIT(0))

+#define EPWMCLK_EN_SHIFT 8
+
+#define PWM_CELL_SIZE 3
+
#define NUM_PWM_CHANNEL 2 /* EHRPWM channels */

struct ehrpwm_pwm_chip {
@@ -392,12 +400,27 @@ static const struct pwm_ops ehrpwm_pwm_ops = {
.owner = THIS_MODULE,
};

+#ifdef CONFIG_OF
+static const struct of_device_id ehrpwm_of_match[] = {
+ {
+ .compatible = "ti,am33xx-ehrpwm",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ehrpwm_of_match);
+#endif
+
static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev)
{
int ret;
struct resource *r;
struct clk *clk;
struct ehrpwm_pwm_chip *pc;
+ struct pinctrl *pinctrl;
+
+ pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
+ if (IS_ERR(pinctrl))
+ dev_warn(&pdev->dev, "failed to configure pins from driver\n");

pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
if (!pc) {
@@ -419,6 +442,7 @@ static int __devinit ehrpwm_pwm_probe(struct platform_device *pdev)

pc->chip.dev = &pdev->dev;
pc->chip.ops = &ehrpwm_pwm_ops;
+ pc->chip.of_pwm_n_cells = PWM_CELL_SIZE;
pc->chip.base = -1;
pc->chip.npwm = NUM_PWM_CHANNEL;

@@ -437,8 +461,11 @@ 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);
+ pwmss_submodule_state_change(pdev->dev.parent, EPWMCLK_EN_SHIFT, true);
+ pm_runtime_put_sync(&pdev->dev);
+
platform_set_drvdata(pdev, pc);
return 0;
}
@@ -447,6 +474,10 @@ 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);
+ pwmss_submodule_state_change(pdev->dev.parent, EPWMCLK_EN_SHIFT, false);
+ pm_runtime_put_sync(&pdev->dev);
+
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return pwmchip_remove(&pc->chip);
@@ -454,7 +485,9 @@ 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 = of_match_ptr(ehrpwm_of_match),
},
.probe = ehrpwm_pwm_probe,
.remove = __devexit_p(ehrpwm_pwm_remove),
--
1.7.0.4


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