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@xxxxxx>
Cc: Grant Likely <grant.likely@xxxxxxxxxxxx>
Cc: Rob Herring <rob.herring@xxxxxxxxxxx>
Cc: Rob Landley <rob@xxxxxxxxxxx>
---
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... aa2ed0a... A Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
:100644 100644 d3c1dff... fba7f9b... M drivers/pwm/pwm-tiehrpwm.c
.../devicetree/bindings/pwm/pwm-tiehrpwm.txt | 25 ++++++++++
drivers/pwm/pwm-tiehrpwm.c | 49 +++++++++++++++++++-
2 files changed, 72 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..fba7f9b 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 "tipwmss.h"
/* EHRPWM registers and bits definitions */
@@ -107,6 +110,13 @@
#define AQCSFRC_CSFA_FRCHIGH BIT(1)
#define AQCSFRC_CSFA_DISSWFRC (BIT(1) | BIT(0))
+#define EPWMCLK_EN BIT(8)
+#define EPWMCLK_STOP_REQ BIT(9)
+
+#define EPWMCLK_EN_ACK BIT(8)
+
+#define PWM_CELL_SIZE 3
+
#define NUM_PWM_CHANNEL 2 /* EHRPWM channels */
struct ehrpwm_pwm_chip {
@@ -392,6 +402,16 @@ 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;
@@ -419,6 +439,7 @@ 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;
@@ -437,16 +458,38 @@ 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);
+ if (!(pwmss_submodule_state_change(pdev->dev.parent, EPWMCLK_EN) &
+ EPWMCLK_EN_ACK)) {
+ dev_err(&pdev->dev, "PWMSS config space clock enable failure\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, 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 +497,9 @@ 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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