[PATCH v2 1/3] pwm: ftm: fix one bug of wrong counting the use counter.

[Xiubo Li]

No matter what times the FTM pwm is enabled, the use_count will
always be one.

Signed-off-by: Xiubo Li <***@freescale.com>
---
drivers/pwm/pwm-fsl-ftm.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index 0f2cc7e..1150598 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -299,7 +299,7 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
{
int ret;

- if (fpc->use_count != 0)
+ if (fpc->use_count++ != 0)
return 0;

/* select counter clock source */
@@ -316,8 +316,6 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
return ret;
}

- fpc->use_count++;
-
return 0;
}

[Xiubo Li]

This patch is to prepare for adding PM support for FTM pwm driver
using callback function suspend and resume in .driver.pm of
platform_driver.

Signed-off-by: Xiubo Li <***@freescale.com>
---
drivers/pwm/pwm-fsl-ftm.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index 1150598..9bfbea5 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -397,12 +397,23 @@ static int fsl_pwm_init(struct fsl_pwm_chip *fpc)
return 0;
}

+static bool fsl_pwm_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ case FTM_CNT:
+ return true;
+ }
+ return false;
+}
+
static const struct regmap_config fsl_pwm_regmap_config = {
.reg_bits = 32,
.reg_stride = 4,
.val_bits = 32,

.max_register = FTM_PWMLOAD,
+ .volatile_reg = fsl_pwm_volatile_reg,
+ .cache_type = REGCACHE_RBTREE,
};

static int fsl_pwm_probe(struct platform_device *pdev)

[Xiubo Li]

Add PM support for FTM pwm driver using callback function suspend
and resume in .driver.pm of platform_driver.

Signed-off-by: Xiubo Li <***@freescale.com>
---
drivers/pwm/pwm-fsl-ftm.c | 49 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 48 insertions(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index 9bfbea5..666e1be 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -17,6 +17,7 @@
#include <linux/mutex.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
+#include <linux/pm.h>
#include <linux/pwm.h>
#include <linux/regmap.h>
#include <linux/slab.h>
@@ -436,7 +437,7 @@ static int fsl_pwm_probe(struct platform_device *pdev)
if (IS_ERR(base))
return PTR_ERR(base);

- fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
+ fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "ftm_sys", base,
&fsl_pwm_regmap_config);
if (IS_ERR(fpc->regmap)) {
dev_err(&pdev->dev, "regmap init failed\n");
@@ -487,6 +488,51 @@ static int fsl_pwm_remove(struct platform_device *pdev)
return pwmchip_remove(&fpc->chip);
}

+#ifdef CONFIG_PM_SLEEP
+static int fsl_pwm_suspend(struct device *dev)
+{
+ struct fsl_pwm_chip *fpc = dev_get_drvdata(dev);
+ u32 val;
+
+ regcache_cache_only(fpc->regmap, true);
+ regcache_mark_dirty(fpc->regmap);
+
+ /* read from cache */
+ regmap_read(fpc->regmap, FTM_OUTMASK, &val);
+ if ((val & 0xFF) != 0xFF) {
+ clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
+ clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
+ clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);
+ }
+
+ return 0;
+}
+
+static int fsl_pwm_resume(struct device *dev)
+{
+ struct fsl_pwm_chip *fpc = dev_get_drvdata(dev);
+ u32 val;
+
+ /* read from cache */
+ regmap_read(fpc->regmap, FTM_OUTMASK, &val);
+ if ((val & 0xFF) != 0xFF) {
+ clk_prepare_enable(fpc->clk[FSL_PWM_CLK_SYS]);
+ clk_prepare_enable(fpc->clk[fpc->cnt_select]);
+ clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]);
+ }
+
+ /* restore all registers from cache */
+ regcache_cache_only(fpc->regmap, false);
+ regcache_sync(fpc->regmap);
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops fsl_pwm_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(fsl_pwm_suspend, fsl_pwm_resume)
+};
+
static const struct of_device_id fsl_pwm_dt_ids[] = {
{ .compatible = "fsl,vf610-ftm-pwm", },
{ /* sentinel */ }
@@ -497,6 +543,7 @@ static struct platform_driver fsl_pwm_driver = {
.driver = {
.name = "fsl-ftm-pwm",
.of_match_table = fsl_pwm_dt_ids,
+ .pm = &fsl_pwm_pm_ops,
},
.probe = fsl_pwm_probe,
.remove = fsl_pwm_remove,