2014-04-29 04:18:21

by Xiubo Li

[permalink] [raw]
Subject: [PATCHv2 0/4] FTM PWM adds regmap and endianness support.

Convert to direct regmap API usage. Since the regmap core has already
support rich endianness modes of device, this patch convert to direct
regmap API usage, preparing to support big endianness for LS1 SoC.

Using the regmag framework will be more easy to support the endiannesses
switching of one same device driver on different SoCs.

The endianness scenarios are:
SoC | CPU | FTM-PWM | 'big-endian' property is needed?
--------|--------|---------|---------------------------------
Vybird | LE | LE | No
LS1 | LE | BE | Yes
LS2 | LE | LE | No



Changes in V2:
- Adds detail descriptions of these patches.


Xiubo Li (4):
Documentation: Add 'big-endian' property for FTM PWM.
pwm: ftm-pwm: Clean up the code.
pwm: ftm-pwm: Convert to direct regmap API usage.
pwm: ftm-pwm: Add big-endian support

.../devicetree/bindings/pwm/pwm-fsl-ftm.txt | 12 ++-
drivers/pwm/pwm-fsl-ftm.c | 96 ++++++++++++----------
2 files changed, 64 insertions(+), 44 deletions(-)

--
1.8.4


2014-04-29 04:18:25

by Xiubo Li

[permalink] [raw]
Subject: [PATCHv2 3/4] pwm: ftm-pwm: Convert to direct regmap API usage.

Since the regmap core has already support rich endianness modes of
device, this patch convert to direct regmap API usage, preparing to
support big endianness for LS1 SoC.

Using the regmag framework will be more easy to support the endiannesses
switching of one same device driver on different SoCs.

Signed-off-by: Xiubo Li <[email protected]>
---
drivers/pwm/pwm-fsl-ftm.c | 83 +++++++++++++++++++++++++----------------------
1 file changed, 44 insertions(+), 39 deletions(-)

diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index 4a4ad58..5d999c1 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -18,6 +18,7 @@
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
+#include <linux/regmap.h>
#include <linux/slab.h>

#define FTM_SC 0x00
@@ -82,7 +83,7 @@ struct fsl_pwm_chip {
unsigned int cnt_select;
unsigned int clk_ps;

- void __iomem *base;
+ struct regmap *regmap;

int period_ns;

@@ -218,10 +219,11 @@ static unsigned long fsl_pwm_calculate_duty(struct fsl_pwm_chip *fpc,
unsigned long period_ns,
unsigned long duty_ns)
{
- unsigned long long val, duty;
+ unsigned long long duty;
+ u32 val;

- val = readl(fpc->base + FTM_MOD);
- duty = duty_ns * (val + 1);
+ regmap_read(fpc->regmap, FTM_MOD, &val);
+ duty = (unsigned long long)duty_ns * (val + 1);
do_div(duty, period_ns);

return (unsigned long)duty;
@@ -231,7 +233,7 @@ static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
- u32 val, period, duty;
+ u32 period, duty;

mutex_lock(&fpc->lock);

@@ -256,11 +258,9 @@ static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
return -EINVAL;
}

- val = readl(fpc->base + FTM_SC);
- val &= ~FTM_SC_PS_MASK;
- val |= fpc->clk_ps;
- writel(val, fpc->base + FTM_SC);
- writel(period - 1, fpc->base + FTM_MOD);
+ regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_PS_MASK,
+ fpc->clk_ps);
+ regmap_write(fpc->regmap, FTM_MOD, period - 1);

fpc->period_ns = period_ns;
}
@@ -269,8 +269,9 @@ static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,

duty = fsl_pwm_calculate_duty(fpc, period_ns, duty_ns);

- writel(FTM_CSC_MSB | FTM_CSC_ELSB, fpc->base + FTM_CSC(pwm->hwpwm));
- writel(duty, fpc->base + FTM_CV(pwm->hwpwm));
+ regmap_write(fpc->regmap, FTM_CSC(pwm->hwpwm),
+ FTM_CSC_MSB | FTM_CSC_ELSB);
+ regmap_write(fpc->regmap, FTM_CV(pwm->hwpwm), duty);

return 0;
}
@@ -282,31 +283,28 @@ static int fsl_pwm_set_polarity(struct pwm_chip *chip,
struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
u32 val;

- val = readl(fpc->base + FTM_POL);
+ regmap_read(fpc->regmap, FTM_POL, &val);

if (polarity == PWM_POLARITY_INVERSED)
val |= BIT(pwm->hwpwm);
else
val &= ~BIT(pwm->hwpwm);

- writel(val, fpc->base + FTM_POL);
+ regmap_write(fpc->regmap, FTM_POL, val);

return 0;
}

static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
{
- u32 val;
int ret;

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

/* select counter clock source */
- val = readl(fpc->base + FTM_SC);
- val &= ~FTM_SC_CLK_MASK;
- val |= FTM_SC_CLK(fpc->cnt_select);
- writel(val, fpc->base + FTM_SC);
+ regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK,
+ FTM_SC_CLK(fpc->cnt_select));

ret = clk_prepare_enable(fpc->clk[fpc->cnt_select]);
if (ret)
@@ -326,13 +324,10 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
- u32 val;
int ret;

mutex_lock(&fpc->lock);
- val = readl(fpc->base + FTM_OUTMASK);
- val &= ~BIT(pwm->hwpwm);
- writel(val, fpc->base + FTM_OUTMASK);
+ regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm), 0);

ret = fsl_counter_clock_enable(fpc);
mutex_unlock(&fpc->lock);
@@ -342,8 +337,6 @@ static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)

static void fsl_counter_clock_disable(struct fsl_pwm_chip *fpc)
{
- u32 val;
-
/*
* already disabled, do nothing
*/
@@ -355,9 +348,7 @@ static void fsl_counter_clock_disable(struct fsl_pwm_chip *fpc)
return;

/* no users left, disable PWM counter clock */
- val = readl(fpc->base + FTM_SC);
- val &= ~FTM_SC_CLK_MASK;
- writel(val, fpc->base + FTM_SC);
+ regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK, 0);

clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
@@ -369,14 +360,12 @@ static void fsl_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
u32 val;

mutex_lock(&fpc->lock);
- val = readl(fpc->base + FTM_OUTMASK);
- val |= BIT(pwm->hwpwm);
- writel(val, fpc->base + FTM_OUTMASK);
+ regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm),
+ BIT(pwm->hwpwm));

fsl_counter_clock_disable(fpc);

- val = readl(fpc->base + FTM_OUTMASK);
-
+ regmap_read(fpc->regmap, FTM_OUTMASK, &val);
if ((val & 0xFF) == 0xFF)
fpc->period_ns = 0;

@@ -401,19 +390,28 @@ static int fsl_pwm_init(struct fsl_pwm_chip *fpc)
if (ret)
return ret;

- writel(0x00, fpc->base + FTM_CNTIN);
- writel(0x00, fpc->base + FTM_OUTINIT);
- writel(0xFF, fpc->base + FTM_OUTMASK);
+ regmap_write(fpc->regmap, FTM_CNTIN, 0x00);
+ regmap_write(fpc->regmap, FTM_OUTINIT, 0x00);
+ regmap_write(fpc->regmap, FTM_OUTMASK, 0xFF);

clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_SYS]);

return 0;
}

+static struct regmap_config fsl_pwm_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+
+ .max_register = FTM_PWMLOAD,
+};
+
static int fsl_pwm_probe(struct platform_device *pdev)
{
struct fsl_pwm_chip *fpc;
struct resource *res;
+ void __iomem *base;
int ret;

fpc = devm_kzalloc(&pdev->dev, sizeof(*fpc), GFP_KERNEL);
@@ -425,9 +423,16 @@ static int fsl_pwm_probe(struct platform_device *pdev)
fpc->chip.dev = &pdev->dev;

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- fpc->base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(fpc->base))
- return PTR_ERR(fpc->base);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ fpc->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
+ &fsl_pwm_regmap_config);
+ if (IS_ERR(fpc->regmap)) {
+ dev_err(&pdev->dev, "regmap init failed\n");
+ return PTR_ERR(fpc->regmap);
+ }

fpc->clk[FSL_PWM_CLK_SYS] = devm_clk_get(&pdev->dev, "ftm_sys");
if (IS_ERR(fpc->clk[FSL_PWM_CLK_SYS])) {
--
1.8.4

2014-04-29 04:18:23

by Xiubo Li

[permalink] [raw]
Subject: [PATCHv2 1/4] Documentation: Add 'big-endian' property for FTM PWM.

This add the big endianness usage in the binding docuementation, which
will run on LS1 SoC.

Now for the following scenarios:
SoC | CPU | FTM-PWM | 'big-endian' property is needed?
--------|--------|---------|---------------------------------
Vybird | LE | LE | No
LS1 | LE | BE | Yes
LS2 | LE | LE | No

Signed-off-by: Xiubo Li <[email protected]>
---
Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt b/Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt
index 0bda229..346e2eb 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm-fsl-ftm.txt
@@ -1,5 +1,13 @@
Freescale FlexTimer Module (FTM) PWM controller

+The endianness of the FTM PWM devices on different SoCs:
+SoC | CPU | FTM-PWM | 'big-endian' property is needed?
+--------|--------|---------|---------------------------------
+Vybird | LE | LE | No
+LS1 | LE | BE | Yes
+LS2 | LE | LE | No
+
+
Required properties:
- compatible: Should be "fsl,vf610-ftm-pwm".
- reg: Physical base address and length of the controller's registers
@@ -16,7 +24,8 @@ Required properties:
- pinctrl-names: Must contain a "default" entry.
- pinctrl-NNN: One property must exist for each entry in pinctrl-names.
See pinctrl/pinctrl-bindings.txt for details of the property values.
-
+- big-endian: One boolean property, for all the device registers, the BE mode
+ will be in use if it's present, or the LE mode will be in use.

Example:

@@ -32,4 +41,5 @@ pwm0: pwm@40038000 {
<&clks VF610_CLK_FTM0_EXT_FIX_EN>;
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_pwm0_1>;
+ big-endian;
};
--
1.8.4

2014-04-29 04:18:28

by Xiubo Li

[permalink] [raw]
Subject: [PATCHv2 4/4] pwm: ftm-pwm: Add big-endian support

This add the big endianness support for the FTM PWM driver, which
will run on LS1 SoC.

Now for the following scenarios:
SoC | CPU | FTM-PWM | 'big-endian' property is needed?
---------|--------|---------|---------------------------------
Vybird | LE | LE | No
LS1 | LE | BE | Yes
LS2 | LE | LE | No

Signed-off-by: Xiubo Li <[email protected]>
---
drivers/pwm/pwm-fsl-ftm.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index 5d999c1..9a82741 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -409,6 +409,7 @@ static struct regmap_config fsl_pwm_regmap_config = {

static int fsl_pwm_probe(struct platform_device *pdev)
{
+ struct device_node *np = pdev->dev.of_node;
struct fsl_pwm_chip *fpc;
struct resource *res;
void __iomem *base;
@@ -422,6 +423,11 @@ static int fsl_pwm_probe(struct platform_device *pdev)

fpc->chip.dev = &pdev->dev;

+ if (of_property_read_bool(np, "big-endian"))
+ fsl_pwm_regmap_config.val_format_endian = REGMAP_ENDIAN_BIG;
+ else
+ fsl_pwm_regmap_config.val_format_endian = REGMAP_ENDIAN_NATIVE;
+
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(base))
--
1.8.4

2014-04-29 04:18:54

by Xiubo Li

[permalink] [raw]
Subject: [PATCHv2 2/4] pwm: ftm-pwm: Clean up the code.

This patch intends to prepare for converting to direct regmap
API usage.

Signed-off-by: Xiubo Li <[email protected]>
---
drivers/pwm/pwm-fsl-ftm.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index 420169e..4a4ad58 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -21,11 +21,10 @@
#include <linux/slab.h>

#define FTM_SC 0x00
-#define FTM_SC_CLK_MASK 0x3
-#define FTM_SC_CLK_SHIFT 3
-#define FTM_SC_CLK(c) (((c) + 1) << FTM_SC_CLK_SHIFT)
+#define FTM_SC_CLK_MASK_SHIFT 3
+#define FTM_SC_CLK_MASK (3 << FTM_SC_CLK_MASK_SHIFT)
+#define FTM_SC_CLK(c) (((c) + 1) << FTM_SC_CLK_MASK_SHIFT)
#define FTM_SC_PS_MASK 0x7
-#define FTM_SC_PS_SHIFT 0

#define FTM_CNT 0x04
#define FTM_MOD 0x08
@@ -258,7 +257,7 @@ static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
}

val = readl(fpc->base + FTM_SC);
- val &= ~(FTM_SC_PS_MASK << FTM_SC_PS_SHIFT);
+ val &= ~FTM_SC_PS_MASK;
val |= fpc->clk_ps;
writel(val, fpc->base + FTM_SC);
writel(period - 1, fpc->base + FTM_MOD);
@@ -305,7 +304,7 @@ static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)

/* select counter clock source */
val = readl(fpc->base + FTM_SC);
- val &= ~(FTM_SC_CLK_MASK << FTM_SC_CLK_SHIFT);
+ val &= ~FTM_SC_CLK_MASK;
val |= FTM_SC_CLK(fpc->cnt_select);
writel(val, fpc->base + FTM_SC);

@@ -357,7 +356,7 @@ static void fsl_counter_clock_disable(struct fsl_pwm_chip *fpc)

/* no users left, disable PWM counter clock */
val = readl(fpc->base + FTM_SC);
- val &= ~(FTM_SC_CLK_MASK << FTM_SC_CLK_SHIFT);
+ val &= ~FTM_SC_CLK_MASK;
writel(val, fpc->base + FTM_SC);

clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
--
1.8.4