2019-01-14 08:23:57

by Ryder Lee

[permalink] [raw]
Subject: [PATCH 1/5] pwm: mediatek: add a property "mediatek,num-pwms"

This adds a property "mediatek,num-pwms" to avoid having an endless
list of compatibles with no other differences for the same driver.

Signed-off-by: Ryder Lee <[email protected]>
---
drivers/pwm/pwm-mediatek.c | 25 +++++++++++--------------
1 file changed, 11 insertions(+), 14 deletions(-)

diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c
index eb6674c..37daa84 100644
--- a/drivers/pwm/pwm-mediatek.c
+++ b/drivers/pwm/pwm-mediatek.c
@@ -55,7 +55,6 @@ enum {
};

struct mtk_pwm_platform_data {
- unsigned int num_pwms;
bool pwm45_fixup;
bool has_clks;
};
@@ -226,10 +225,11 @@ static void mtk_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)

static int mtk_pwm_probe(struct platform_device *pdev)
{
+ struct device_node *np = pdev->dev.of_node;
const struct mtk_pwm_platform_data *data;
struct mtk_pwm_chip *pc;
struct resource *res;
- unsigned int i;
+ unsigned int i, num_pwms;
int ret;

pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
@@ -246,7 +246,13 @@ static int mtk_pwm_probe(struct platform_device *pdev)
if (IS_ERR(pc->regs))
return PTR_ERR(pc->regs);

- for (i = 0; i < data->num_pwms + 2 && pc->soc->has_clks; i++) {
+ ret = of_property_read_u32(np, "mediatek,num-pwms", &num_pwms);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to get pwm number: %d\n", ret);
+ return ret;
+ }
+
+ for (i = 0; i < num_pwms + 2 && pc->soc->has_clks; i++) {
pc->clks[i] = devm_clk_get(&pdev->dev, mtk_pwm_clk_name[i]);
if (IS_ERR(pc->clks[i])) {
dev_err(&pdev->dev, "clock: %s fail: %ld\n",
@@ -260,7 +266,7 @@ static int mtk_pwm_probe(struct platform_device *pdev)
pc->chip.dev = &pdev->dev;
pc->chip.ops = &mtk_pwm_ops;
pc->chip.base = -1;
- pc->chip.npwm = data->num_pwms;
+ pc->chip.npwm = num_pwms;

ret = pwmchip_add(&pc->chip);
if (ret < 0) {
@@ -279,32 +285,23 @@ static int mtk_pwm_remove(struct platform_device *pdev)
}

static const struct mtk_pwm_platform_data mt2712_pwm_data = {
- .num_pwms = 8,
- .pwm45_fixup = false,
- .has_clks = true,
-};
-
-static const struct mtk_pwm_platform_data mt7622_pwm_data = {
- .num_pwms = 6,
.pwm45_fixup = false,
.has_clks = true,
};

static const struct mtk_pwm_platform_data mt7623_pwm_data = {
- .num_pwms = 5,
.pwm45_fixup = true,
.has_clks = true,
};

static const struct mtk_pwm_platform_data mt7628_pwm_data = {
- .num_pwms = 4,
.pwm45_fixup = true,
.has_clks = false,
};

static const struct of_device_id mtk_pwm_of_match[] = {
{ .compatible = "mediatek,mt2712-pwm", .data = &mt2712_pwm_data },
- { .compatible = "mediatek,mt7622-pwm", .data = &mt7622_pwm_data },
+ { .compatible = "mediatek,mt7622-pwm", .data = &mt2712_pwm_data },
{ .compatible = "mediatek,mt7623-pwm", .data = &mt7623_pwm_data },
{ .compatible = "mediatek,mt7628-pwm", .data = &mt7628_pwm_data },
{ },
--
1.9.1



2019-01-14 08:22:54

by Ryder Lee

[permalink] [raw]
Subject: [PATCH 3/5] arm64: dts: mt7622: add a property "mediatek,num-pwms" for PWM

This adds a property "mediatek,num-pwms" for PWM controller.

Signed-off-by: Ryder Lee <[email protected]>
---
arch/arm64/boot/dts/mediatek/mt7622.dtsi | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/mediatek/mt7622.dtsi b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
index 8fc4aa7..ab016cf 100644
--- a/arch/arm64/boot/dts/mediatek/mt7622.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
@@ -436,6 +436,7 @@
<&pericfg CLK_PERI_PWM6_PD>;
clock-names = "top", "main", "pwm1", "pwm2", "pwm3", "pwm4",
"pwm5", "pwm6";
+ mediatek,num-pwms = <6>;
status = "disabled";
};

--
1.9.1


2019-01-14 08:22:57

by Ryder Lee

[permalink] [raw]
Subject: [PATCH 5/5] dt-bindings: pwm: update bindings for MT7629 SoC

This updates bindings for MT7629 pwm controller.

Signed-off-by: Ryder Lee <[email protected]>
---
Documentation/devicetree/bindings/pwm/pwm-mediatek.txt | 1 +
1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt b/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
index f9e2d1f..f7e7784 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
@@ -6,6 +6,7 @@ Required properties:
- "mediatek,mt7622-pwm": found on mt7622 SoC.
- "mediatek,mt7623-pwm": found on mt7623 SoC.
- "mediatek,mt7628-pwm": found on mt7628 SoC.
+ - "mediatek,mt7629-pwm", "mediatek,mt7622-pwm": found on mt7629 SoC.
- reg: physical base address and length of the controller's registers.
- #pwm-cells: must be 2. See pwm.txt in this directory for a description of
the cell format.
--
1.9.1


2019-01-14 08:23:14

by Ryder Lee

[permalink] [raw]
Subject: [PATCH 2/5] dt-bindings: pwm: add a property "mediatek,num-pwms"

This adds a property "mediatek,num-pwms" in example so that we could
set the number of PWM channels via device tree.

Signed-off-by: Ryder Lee <[email protected]>
---
Documentation/devicetree/bindings/pwm/pwm-mediatek.txt | 2 ++
1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt b/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
index 991728c..f9e2d1f 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
@@ -20,6 +20,7 @@ Required properties:
- pinctrl-names: Must contain a "default" entry.
- pinctrl-0: One property must exist for each entry in pinctrl-names.
See pinctrl/pinctrl-bindings.txt for details of the property values.
+ - mediatek,num-pwms: the number of PWM channels.

Example:
pwm0: pwm@11006000 {
@@ -37,4 +38,5 @@ Example:
"pwm3", "pwm4", "pwm5";
pinctrl-names = "default";
pinctrl-0 = <&pwm0_pins>;
+ mediatek,num-pwms = <5>;
};
--
1.9.1


2019-01-14 08:24:22

by Ryder Lee

[permalink] [raw]
Subject: [PATCH 4/5] arm: dts: mt7623: add a property "mediatek,num-pwms" for PWM

This adds a property "mediatek,num-pwms" for PWM controller.

Signed-off-by: Ryder Lee <[email protected]>
---
arch/arm/boot/dts/mt7623.dtsi | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm/boot/dts/mt7623.dtsi b/arch/arm/boot/dts/mt7623.dtsi
index 98f1159..2dd2f93 100644
--- a/arch/arm/boot/dts/mt7623.dtsi
+++ b/arch/arm/boot/dts/mt7623.dtsi
@@ -443,6 +443,7 @@
<&pericfg CLK_PERI_PWM5>;
clock-names = "top", "main", "pwm1", "pwm2",
"pwm3", "pwm4", "pwm5";
+ mediatek,num-pwms = <5>;
status = "disabled";
};

--
1.9.1


2019-01-14 11:18:44

by Matthias Brugger

[permalink] [raw]
Subject: Re: [PATCH 1/5] pwm: mediatek: add a property "mediatek,num-pwms"



On 14/01/2019 09:21, Ryder Lee wrote:
> This adds a property "mediatek,num-pwms" to avoid having an endless
> list of compatibles with no other differences for the same driver.
>
> Signed-off-by: Ryder Lee <[email protected]>
> ---
> drivers/pwm/pwm-mediatek.c | 25 +++++++++++--------------
> 1 file changed, 11 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c
> index eb6674c..37daa84 100644
> --- a/drivers/pwm/pwm-mediatek.c
> +++ b/drivers/pwm/pwm-mediatek.c
> @@ -55,7 +55,6 @@ enum {
> };
>
> struct mtk_pwm_platform_data {
> - unsigned int num_pwms;
> bool pwm45_fixup;
> bool has_clks;
> };
> @@ -226,10 +225,11 @@ static void mtk_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
>
> static int mtk_pwm_probe(struct platform_device *pdev)
> {
> + struct device_node *np = pdev->dev.of_node;
> const struct mtk_pwm_platform_data *data;
> struct mtk_pwm_chip *pc;
> struct resource *res;
> - unsigned int i;
> + unsigned int i, num_pwms;
> int ret;
>
> pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
> @@ -246,7 +246,13 @@ static int mtk_pwm_probe(struct platform_device *pdev)
> if (IS_ERR(pc->regs))
> return PTR_ERR(pc->regs);
>
> - for (i = 0; i < data->num_pwms + 2 && pc->soc->has_clks; i++) {
> + ret = of_property_read_u32(np, "mediatek,num-pwms", &num_pwms);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "failed to get pwm number: %d\n", ret);
> + return ret;
> + }
> +
> + for (i = 0; i < num_pwms + 2 && pc->soc->has_clks; i++) {
> pc->clks[i] = devm_clk_get(&pdev->dev, mtk_pwm_clk_name[i]);
> if (IS_ERR(pc->clks[i])) {
> dev_err(&pdev->dev, "clock: %s fail: %ld\n",
> @@ -260,7 +266,7 @@ static int mtk_pwm_probe(struct platform_device *pdev)
> pc->chip.dev = &pdev->dev;
> pc->chip.ops = &mtk_pwm_ops;
> pc->chip.base = -1;
> - pc->chip.npwm = data->num_pwms;
> + pc->chip.npwm = num_pwms;
>
> ret = pwmchip_add(&pc->chip);
> if (ret < 0) {
> @@ -279,32 +285,23 @@ static int mtk_pwm_remove(struct platform_device *pdev)
> }
>
> static const struct mtk_pwm_platform_data mt2712_pwm_data = {
> - .num_pwms = 8,
> - .pwm45_fixup = false,
> - .has_clks = true,
> -};
> -
> -static const struct mtk_pwm_platform_data mt7622_pwm_data = {
> - .num_pwms = 6,
> .pwm45_fixup = false,
> .has_clks = true,
> };

From my point of view that's not perfect. We should make sure that a newer
kernel does not break with an older device tree and vice versa.
Just imagine I use some board where u-boot passes the device tree to the kernel,
I update the kernel and PWM is broken.

So also it is crappy we will need to have the num_pwms variable for the older
boards.
Maybe put a switch in the probe function which checks the compatible with a
comment message saying that this is for legacy device tree, so that no new
contributer just copys the wrong code.

What do you think?
Regards,
Matthias

>
> static const struct mtk_pwm_platform_data mt7623_pwm_data = {
> - .num_pwms = 5,
> .pwm45_fixup = true,
> .has_clks = true,
> };
>
> static const struct mtk_pwm_platform_data mt7628_pwm_data = {
> - .num_pwms = 4,
> .pwm45_fixup = true,
> .has_clks = false,
> };
>
> static const struct of_device_id mtk_pwm_of_match[] = {
> { .compatible = "mediatek,mt2712-pwm", .data = &mt2712_pwm_data },
> - { .compatible = "mediatek,mt7622-pwm", .data = &mt7622_pwm_data },
> + { .compatible = "mediatek,mt7622-pwm", .data = &mt2712_pwm_data },
> { .compatible = "mediatek,mt7623-pwm", .data = &mt7623_pwm_data },
> { .compatible = "mediatek,mt7628-pwm", .data = &mt7628_pwm_data },
> { },
>

2019-01-14 11:20:40

by Matthias Brugger

[permalink] [raw]
Subject: Re: [PATCH 2/5] dt-bindings: pwm: add a property "mediatek,num-pwms"



On 14/01/2019 09:21, Ryder Lee wrote:
> This adds a property "mediatek,num-pwms" in example so that we could
> set the number of PWM channels via device tree.
>
> Signed-off-by: Ryder Lee <[email protected]>

Reviewed-by: Matthias Brugger <[email protected]>

> ---
> Documentation/devicetree/bindings/pwm/pwm-mediatek.txt | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt b/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
> index 991728c..f9e2d1f 100644
> --- a/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
> +++ b/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
> @@ -20,6 +20,7 @@ Required properties:
> - pinctrl-names: Must contain a "default" entry.
> - pinctrl-0: One property must exist for each entry in pinctrl-names.
> See pinctrl/pinctrl-bindings.txt for details of the property values.
> + - mediatek,num-pwms: the number of PWM channels.
>
> Example:
> pwm0: pwm@11006000 {
> @@ -37,4 +38,5 @@ Example:
> "pwm3", "pwm4", "pwm5";
> pinctrl-names = "default";
> pinctrl-0 = <&pwm0_pins>;
> + mediatek,num-pwms = <5>;
> };
>

2019-01-14 11:21:03

by Matthias Brugger

[permalink] [raw]
Subject: Re: [PATCH 5/5] dt-bindings: pwm: update bindings for MT7629 SoC



On 14/01/2019 09:21, Ryder Lee wrote:
> This updates bindings for MT7629 pwm controller.
>
> Signed-off-by: Ryder Lee <[email protected]>

Reviewed-by: Matthias Brugger <[email protected]>

> ---
> Documentation/devicetree/bindings/pwm/pwm-mediatek.txt | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt b/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
> index f9e2d1f..f7e7784 100644
> --- a/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
> +++ b/Documentation/devicetree/bindings/pwm/pwm-mediatek.txt
> @@ -6,6 +6,7 @@ Required properties:
> - "mediatek,mt7622-pwm": found on mt7622 SoC.
> - "mediatek,mt7623-pwm": found on mt7623 SoC.
> - "mediatek,mt7628-pwm": found on mt7628 SoC.
> + - "mediatek,mt7629-pwm", "mediatek,mt7622-pwm": found on mt7629 SoC.
> - reg: physical base address and length of the controller's registers.
> - #pwm-cells: must be 2. See pwm.txt in this directory for a description of
> the cell format.
>

2019-01-16 11:02:59

by Uwe Kleine-König

[permalink] [raw]
Subject: Re: [PATCH 1/5] pwm: mediatek: add a property "mediatek,num-pwms"

On Mon, Jan 14, 2019 at 04:21:20PM +0800, Ryder Lee wrote:
> This adds a property "mediatek,num-pwms" to avoid having an endless
> list of compatibles with no other differences for the same driver.

I seem to recall having said something similar before, but maybe this
was a different series (there is no v2 or higher in the Subject ...)

I think it would be sensible to drop the vendor prefix and go with plain
"num-pwms" (or "npwms" to align to "ngpios" in the gpio bindings).

> Signed-off-by: Ryder Lee <[email protected]>
> ---
> drivers/pwm/pwm-mediatek.c | 25 +++++++++++--------------
> 1 file changed, 11 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c
> index eb6674c..37daa84 100644
> --- a/drivers/pwm/pwm-mediatek.c
> +++ b/drivers/pwm/pwm-mediatek.c
> @@ -55,7 +55,6 @@ enum {
> };
>
> struct mtk_pwm_platform_data {
> - unsigned int num_pwms;
> bool pwm45_fixup;
> bool has_clks;
> };
> @@ -226,10 +225,11 @@ static void mtk_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
>
> static int mtk_pwm_probe(struct platform_device *pdev)
> {
> + struct device_node *np = pdev->dev.of_node;
> const struct mtk_pwm_platform_data *data;
> struct mtk_pwm_chip *pc;
> struct resource *res;
> - unsigned int i;
> + unsigned int i, num_pwms;
> int ret;
>
> pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
> @@ -246,7 +246,13 @@ static int mtk_pwm_probe(struct platform_device *pdev)
> if (IS_ERR(pc->regs))
> return PTR_ERR(pc->regs);
>
> - for (i = 0; i < data->num_pwms + 2 && pc->soc->has_clks; i++) {
> + ret = of_property_read_u32(np, "mediatek,num-pwms", &num_pwms);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "failed to get pwm number: %d\n", ret);

This sounds wrong. "Failed to get number of pwms" sounds better to my
(non-native) ear.

> + return ret;
> + }
> +
> + for (i = 0; i < num_pwms + 2 && pc->soc->has_clks; i++) {
> pc->clks[i] = devm_clk_get(&pdev->dev, mtk_pwm_clk_name[i]);
> if (IS_ERR(pc->clks[i])) {
> dev_err(&pdev->dev, "clock: %s fail: %ld\n",
> @@ -260,7 +266,7 @@ static int mtk_pwm_probe(struct platform_device *pdev)
> pc->chip.dev = &pdev->dev;
> pc->chip.ops = &mtk_pwm_ops;
> pc->chip.base = -1;
> - pc->chip.npwm = data->num_pwms;
> + pc->chip.npwm = num_pwms;
>
> ret = pwmchip_add(&pc->chip);
> if (ret < 0) {
> @@ -279,32 +285,23 @@ static int mtk_pwm_remove(struct platform_device *pdev)
> }
>
> static const struct mtk_pwm_platform_data mt2712_pwm_data = {
> - .num_pwms = 8,
> - .pwm45_fixup = false,
> - .has_clks = true,
> -};
> -
> -static const struct mtk_pwm_platform_data mt7622_pwm_data = {
> - .num_pwms = 6,
> .pwm45_fixup = false,
> .has_clks = true,

I agree with Matthias Brugger that at least for some time you should be
able to fall back to the right number of pwms if the device tree doesn't
have a num-pwms property.

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | http://www.pengutronix.de/ |

2019-01-17 13:06:08

by Matthias Brugger

[permalink] [raw]
Subject: Re: [PATCH 3/5] arm64: dts: mt7622: add a property "mediatek,num-pwms" for PWM



On 15/01/2019 21:02, Uwe Kleine-König wrote:
> Hello,
>
> On Mon, Jan 14, 2019 at 04:21:22PM +0800, Ryder Lee wrote:
>> This adds a property "mediatek,num-pwms" for PWM controller.
>>
>> Signed-off-by: Ryder Lee <[email protected]>
>> ---
>> arch/arm64/boot/dts/mediatek/mt7622.dtsi | 1 +
>> 1 file changed, 1 insertion(+)
>>
>> diff --git a/arch/arm64/boot/dts/mediatek/mt7622.dtsi b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
>> index 8fc4aa7..ab016cf 100644
>> --- a/arch/arm64/boot/dts/mediatek/mt7622.dtsi
>> +++ b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
>> @@ -436,6 +436,7 @@
>> <&pericfg CLK_PERI_PWM6_PD>;
>> clock-names = "top", "main", "pwm1", "pwm2", "pwm3", "pwm4",
>> "pwm5", "pwm6";
>> + mediatek,num-pwms = <6>;
>> status = "disabled";
>
> Conceptually this patch must go in before the change to the driver.
> Otherwise the pwms are not usable with only patch 1 applied which breaks
> bisectability.
>

The driver should have backwards compatibility to older DTs. So that would need
to be fixed in the driver not in the patch order of the series.

Regards,
Matthias

2019-01-18 01:59:02

by Ryder Lee

[permalink] [raw]
Subject: Re: [PATCH 1/5] pwm: mediatek: add a property "mediatek,num-pwms"

On Mon, 2019-01-14 at 12:16 +0100, Matthias Brugger wrote:
>
> On 14/01/2019 09:21, Ryder Lee wrote:
> > This adds a property "mediatek,num-pwms" to avoid having an endless
> > list of compatibles with no other differences for the same driver.
> >
> > Signed-off-by: Ryder Lee <[email protected]>
> > ---
> > drivers/pwm/pwm-mediatek.c | 25 +++++++++++--------------
> > 1 file changed, 11 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/pwm/pwm-mediatek.c b/drivers/pwm/pwm-mediatek.c
> > index eb6674c..37daa84 100644
> > --- a/drivers/pwm/pwm-mediatek.c
> > +++ b/drivers/pwm/pwm-mediatek.c
> > @@ -55,7 +55,6 @@ enum {
> > };
> >
> > struct mtk_pwm_platform_data {
> > - unsigned int num_pwms;
> > bool pwm45_fixup;
> > bool has_clks;
> > };
> > @@ -226,10 +225,11 @@ static void mtk_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
> >
> > static int mtk_pwm_probe(struct platform_device *pdev)
> > {
> > + struct device_node *np = pdev->dev.of_node;
> > const struct mtk_pwm_platform_data *data;
> > struct mtk_pwm_chip *pc;
> > struct resource *res;
> > - unsigned int i;
> > + unsigned int i, num_pwms;
> > int ret;
> >
> > pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
> > @@ -246,7 +246,13 @@ static int mtk_pwm_probe(struct platform_device *pdev)
> > if (IS_ERR(pc->regs))
> > return PTR_ERR(pc->regs);
> >
> > - for (i = 0; i < data->num_pwms + 2 && pc->soc->has_clks; i++) {
> > + ret = of_property_read_u32(np, "mediatek,num-pwms", &num_pwms);
> > + if (ret < 0) {
> > + dev_err(&pdev->dev, "failed to get pwm number: %d\n", ret);
> > + return ret;
> > + }
> > +
> > + for (i = 0; i < num_pwms + 2 && pc->soc->has_clks; i++) {
> > pc->clks[i] = devm_clk_get(&pdev->dev, mtk_pwm_clk_name[i]);
> > if (IS_ERR(pc->clks[i])) {
> > dev_err(&pdev->dev, "clock: %s fail: %ld\n",
> > @@ -260,7 +266,7 @@ static int mtk_pwm_probe(struct platform_device *pdev)
> > pc->chip.dev = &pdev->dev;
> > pc->chip.ops = &mtk_pwm_ops;
> > pc->chip.base = -1;
> > - pc->chip.npwm = data->num_pwms;
> > + pc->chip.npwm = num_pwms;
> >
> > ret = pwmchip_add(&pc->chip);
> > if (ret < 0) {
> > @@ -279,32 +285,23 @@ static int mtk_pwm_remove(struct platform_device *pdev)
> > }
> >
> > static const struct mtk_pwm_platform_data mt2712_pwm_data = {
> > - .num_pwms = 8,
> > - .pwm45_fixup = false,
> > - .has_clks = true,
> > -};
> > -
> > -static const struct mtk_pwm_platform_data mt7622_pwm_data = {
> > - .num_pwms = 6,
> > .pwm45_fixup = false,
> > .has_clks = true,
> > };
>
> From my point of view that's not perfect. We should make sure that a newer
> kernel does not break with an older device tree and vice versa.
> Just imagine I use some board where u-boot passes the device tree to the kernel,
> I update the kernel and PWM is broken.
>
> So also it is crappy we will need to have the num_pwms variable for the older
> boards.
> Maybe put a switch in the probe function which checks the compatible with a
> comment message saying that this is for legacy device tree, so that no new
> contributer just copys the wrong code.
>
> What do you think?

Okay, I will do that.

Ryder
>
> >
> > static const struct mtk_pwm_platform_data mt7623_pwm_data = {
> > - .num_pwms = 5,
> > .pwm45_fixup = true,
> > .has_clks = true,
> > };
> >
> > static const struct mtk_pwm_platform_data mt7628_pwm_data = {
> > - .num_pwms = 4,
> > .pwm45_fixup = true,
> > .has_clks = false,
> > };
> >
> > static const struct of_device_id mtk_pwm_of_match[] = {
> > { .compatible = "mediatek,mt2712-pwm", .data = &mt2712_pwm_data },
> > - { .compatible = "mediatek,mt7622-pwm", .data = &mt7622_pwm_data },
> > + { .compatible = "mediatek,mt7622-pwm", .data = &mt2712_pwm_data },
> > { .compatible = "mediatek,mt7623-pwm", .data = &mt7623_pwm_data },
> > { .compatible = "mediatek,mt7628-pwm", .data = &mt7628_pwm_data },
> > { },
> >