[PATCH v2 0/4] PWM and keyboard backlight driver for ARM Macs

[PATCH v2 0/4] PWM and keyboard backlight driver for ARM Macs

[Sasha Finkelstein]

Hi,

This is the v2 of the patch series to add PWM and keyboard backlight
drivers for ARM macs. The changes from v1 address the review
comments on that patch set.

v1: https://www.spinics.net/lists/linux-pwm/msg19500.html

Best Regards.

Sasha Finkelstein (4):
  dt-bindings: pwm: Add Apple PWM controller
  pwm: Add Apple PWM controller
  arm64: dts: apple: t8103: Add PWM controller
  MAINTAINERS: Add entries for Apple PWM driver

 .../bindings/pwm/apple,s5l-fpwm.yaml          |  51 +++++++
 MAINTAINERS                                   |   2 +
 arch/arm64/boot/dts/apple/t8103-j293.dts      |  20 +++
 arch/arm64/boot/dts/apple/t8103-j313.dts      |  20 +++
 arch/arm64/boot/dts/apple/t8103.dtsi          |   9 ++
 drivers/pwm/Kconfig                           |  12 ++
 drivers/pwm/Makefile                          |   1 +
 drivers/pwm/pwm-apple.c                       | 127 ++++++++++++++++++
 8 files changed, 242 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pwm/apple,s5l-fpwm.yaml
 create mode 100644 drivers/pwm/pwm-apple.c

-- 
2.37.3

[PATCH v2 1/4] dt-bindings: pwm: Add Apple PWM controller

[Sasha Finkelstein]

Apple SoCs such as the M1 contain a PWM controller used
among other things to control the keyboard backlight.

Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com>
---
 .../bindings/pwm/apple,s5l-fpwm.yaml          | 51 +++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pwm/apple,s5l-fpwm.yaml

diff --git a/Documentation/devicetree/bindings/pwm/apple,s5l-fpwm.yaml b/Documentation/devicetree/bindings/pwm/apple,s5l-fpwm.yaml
new file mode 100644
index 000000000000..142157bff0cd
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/apple,s5l-fpwm.yaml
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pwm/apple,s5l-fpwm.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple FPWM controller
+
+maintainers:
+  - asahi@lists.linux.dev
+  - Sasha Finkelstein <fnkl.kernel@gmail.com>
+
+description: PWM controller used for keyboard backlight on ARM Macs
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - apple,t8103-fpwm
+          - apple,t6000-fpwm
+          - apple,t8112-fpwm
+      - const: apple,s5l-fpwm
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  power-domains:
+    maxItems: 1
+
+  "#pwm-cells":
+    const: 2
+
+required:
+  - compatible
+  - reg
+  - clocks
+
+additionalProperties: false
+
+examples:
+  - |
+    pwm@235044000 {
+      compatible = "apple,t8103-fpwm", "apple,s5l-fpwm";
+      reg = <0x35044000 0x4000>;
+      power-domains = <&ps_fpwm1>;
+      clocks = <&clkref>;
+      #pwm-cells = <2>;
+    };
-- 
2.37.3

Re: [PATCH v2 1/4] dt-bindings: pwm: Add Apple PWM controller

[Krzysztof Kozlowski]

On 02/11/2022 10:15, Sasha Finkelstein wrote:
> Apple SoCs such as the M1 contain a PWM controller used
> among other things to control the keyboard backlight.
> 
> Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com>


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

[PATCH v2 2/4] pwm: Add Apple PWM controller

[Sasha Finkelstein]

Adds the Apple PWM controller driver.

Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com>
---
 drivers/pwm/Kconfig     |  12 ++++
 drivers/pwm/Makefile    |   1 +
 drivers/pwm/pwm-apple.c | 127 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 140 insertions(+)
 create mode 100644 drivers/pwm/pwm-apple.c

diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 60d13a949bc5..c3be11468414 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -51,6 +51,18 @@ config PWM_AB8500
 	  To compile this driver as a module, choose M here: the module
 	  will be called pwm-ab8500.
 
+config PWM_APPLE
+	tristate "Apple SoC PWM support"
+	depends on ARCH_APPLE || COMPILE_TEST
+	help
+	  Generic PWM framework driver for PWM controller present on
+	  Apple SoCs
+
+	  Say Y here if you have an ARM Apple laptop, otherwise say N
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called pwm-apple.
+
 config PWM_ATMEL
 	tristate "Atmel PWM support"
 	depends on ARCH_AT91 || COMPILE_TEST
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 7bf1a29f02b8..19899b912e00 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -2,6 +2,7 @@
 obj-$(CONFIG_PWM)		+= core.o
 obj-$(CONFIG_PWM_SYSFS)		+= sysfs.o
 obj-$(CONFIG_PWM_AB8500)	+= pwm-ab8500.o
+obj-$(CONFIG_PWM_APPLE)		+= pwm-apple.o
 obj-$(CONFIG_PWM_ATMEL)		+= pwm-atmel.o
 obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM)	+= pwm-atmel-hlcdc.o
 obj-$(CONFIG_PWM_ATMEL_TCB)	+= pwm-atmel-tcb.o
diff --git a/drivers/pwm/pwm-apple.c b/drivers/pwm/pwm-apple.c
new file mode 100644
index 000000000000..7b2936346f4e
--- /dev/null
+++ b/drivers/pwm/pwm-apple.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/*
+ * Driver for the Apple SoC PWM controller
+ *
+ * Copyright The Asahi Linux Contributors
+ */
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/pm_runtime.h>
+#include <linux/math64.h>
+
+#define PWM_CONTROL     0x00
+#define PWM_ON_CYCLES   0x1c
+#define PWM_OFF_CYCLES  0x18
+
+#define CTRL_ENABLE        BIT(0)
+#define CTRL_MODE          BIT(2)
+#define CTRL_UPDATE        BIT(5)
+#define CTRL_TRIGGER       BIT(9)
+#define CTRL_INVERT        BIT(10)
+#define CTRL_OUTPUT_ENABLE BIT(14)
+
+struct apple_pwm {
+	struct pwm_chip chip;
+	void __iomem *base;
+	u64 clkrate;
+};
+
+static int apple_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+			   const struct pwm_state *state)
+{
+	struct apple_pwm *fpwm;
+	u64 on_cycles, off_cycles;
+
+	fpwm = container_of(chip, struct apple_pwm, chip);
+	if (state->enabled) {
+		on_cycles = mul_u64_u64_div_u64(fpwm->clkrate,
+						state->duty_cycle, NSEC_PER_SEC);
+		off_cycles = mul_u64_u64_div_u64(fpwm->clkrate,
+						 state->period, NSEC_PER_SEC) - on_cycles;
+		writel(on_cycles, fpwm->base + PWM_ON_CYCLES);
+		writel(off_cycles, fpwm->base + PWM_OFF_CYCLES);
+		writel(CTRL_ENABLE | CTRL_OUTPUT_ENABLE | CTRL_UPDATE,
+		       fpwm->base + PWM_CONTROL);
+	} else {
+		writel(0, fpwm->base + PWM_CONTROL);
+	}
+	return 0;
+}
+
+static void apple_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+			   struct pwm_state *state)
+{
+	struct apple_pwm *fpwm;
+	u32 on_cycles, off_cycles, ctrl;
+
+	fpwm = container_of(chip, struct apple_pwm, chip);
+
+	ctrl = readl(fpwm->base + PWM_CONTROL);
+	on_cycles = readl(fpwm->base + PWM_ON_CYCLES);
+	off_cycles = readl(fpwm->base + PWM_OFF_CYCLES);
+
+	state->enabled = (ctrl & CTRL_ENABLE) && (ctrl & CTRL_OUTPUT_ENABLE);
+	state->polarity = PWM_POLARITY_NORMAL;
+	state->duty_cycle = div_u64(on_cycles, fpwm->clkrate) * NSEC_PER_SEC;
+	state->period = div_u64(off_cycles + on_cycles, fpwm->clkrate) * NSEC_PER_SEC;
+}
+
+static const struct pwm_ops apple_pwm_ops = {
+	.apply = apple_pwm_apply,
+	.get_state = apple_pwm_get_state,
+	.owner = THIS_MODULE,
+};
+
+static int apple_pwm_probe(struct platform_device *pdev)
+{
+	struct apple_pwm *pwm;
+	struct clk *clk;
+	int ret;
+
+	pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
+	if (!pwm)
+		return -ENOMEM;
+
+	pwm->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(pwm->base))
+		return PTR_ERR(pwm->base);
+
+	platform_set_drvdata(pdev, pwm);
+
+	clk = devm_clk_get_enabled(&pdev->dev, NULL);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	pwm->clkrate = clk_get_rate(clk);
+	pwm->chip.dev = &pdev->dev;
+	pwm->chip.npwm = 1;
+	pwm->chip.ops = &apple_pwm_ops;
+
+	ret = devm_pwmchip_add(&pdev->dev, &pwm->chip);
+	return ret;
+}
+
+static const struct of_device_id apple_pwm_of_match[] = {
+	{ .compatible = "apple,s5l-fpwm" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, apple_pwm_of_match);
+
+static struct platform_driver apple_pwm_driver = {
+	.probe = apple_pwm_probe,
+	.driver = {
+		.name = "apple-pwm",
+		.owner = THIS_MODULE,
+		.of_match_table = apple_pwm_of_match,
+	},
+};
+module_platform_driver(apple_pwm_driver);
+
+MODULE_DESCRIPTION("Apple SoC PWM driver");
+MODULE_LICENSE("Dual MIT/GPL");
-- 
2.37.3

RE: [PATCH v2 2/4] pwm: Add Apple PWM controller

[Biju Das]

Hi Sasha Finkelstein,

Thanks for the patch.

> Subject: [PATCH v2 2/4] pwm: Add Apple PWM controller
> 
> Adds the Apple PWM controller driver.
> 
> Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com>
> ---
>  drivers/pwm/Kconfig     |  12 ++++
>  drivers/pwm/Makefile    |   1 +
>  drivers/pwm/pwm-apple.c | 127
> ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 140 insertions(+)
>  create mode 100644 drivers/pwm/pwm-apple.c
> 
> diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index
> 60d13a949bc5..c3be11468414 100644
> --- a/drivers/pwm/Kconfig
> +++ b/drivers/pwm/Kconfig
> @@ -51,6 +51,18 @@ config PWM_AB8500
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called pwm-ab8500.
> 
> +config PWM_APPLE
> +	tristate "Apple SoC PWM support"
> +	depends on ARCH_APPLE || COMPILE_TEST
> +	help
> +	  Generic PWM framework driver for PWM controller present on
> +	  Apple SoCs
> +
> +	  Say Y here if you have an ARM Apple laptop, otherwise say N
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called pwm-apple.
> +
>  config PWM_ATMEL
>  	tristate "Atmel PWM support"
>  	depends on ARCH_AT91 || COMPILE_TEST
> diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index
> 7bf1a29f02b8..19899b912e00 100644
> --- a/drivers/pwm/Makefile
> +++ b/drivers/pwm/Makefile
> @@ -2,6 +2,7 @@
>  obj-$(CONFIG_PWM)		+= core.o
>  obj-$(CONFIG_PWM_SYSFS)		+= sysfs.o
>  obj-$(CONFIG_PWM_AB8500)	+= pwm-ab8500.o
> +obj-$(CONFIG_PWM_APPLE)		+= pwm-apple.o
>  obj-$(CONFIG_PWM_ATMEL)		+= pwm-atmel.o
>  obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM)	+= pwm-atmel-hlcdc.o
>  obj-$(CONFIG_PWM_ATMEL_TCB)	+= pwm-atmel-tcb.o
> diff --git a/drivers/pwm/pwm-apple.c b/drivers/pwm/pwm-apple.c new
> file mode 100644 index 000000000000..7b2936346f4e
> --- /dev/null
> +++ b/drivers/pwm/pwm-apple.c
> @@ -0,0 +1,127 @@
> +// SPDX-License-Identifier: GPL-2.0 OR MIT
> +/*
> + * Driver for the Apple SoC PWM controller
> + *
> + * Copyright The Asahi Linux Contributors  */
> +
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/pwm.h>
> +#include <linux/io.h>
> +#include <linux/clk.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/math64.h>

May be sort header alphabetically??

> +
> +#define PWM_CONTROL     0x00
> +#define PWM_ON_CYCLES   0x1c
> +#define PWM_OFF_CYCLES  0x18
> +
> +#define CTRL_ENABLE        BIT(0)
> +#define CTRL_MODE          BIT(2)
> +#define CTRL_UPDATE        BIT(5)
> +#define CTRL_TRIGGER       BIT(9)
> +#define CTRL_INVERT        BIT(10)
> +#define CTRL_OUTPUT_ENABLE BIT(14)
> +
> +struct apple_pwm {
> +	struct pwm_chip chip;
> +	void __iomem *base;
> +	u64 clkrate;
> +};
> +
> +static int apple_pwm_apply(struct pwm_chip *chip, struct pwm_device
> *pwm,
> +			   const struct pwm_state *state)
> +{
> +	struct apple_pwm *fpwm;
> +	u64 on_cycles, off_cycles;
> +
> +	fpwm = container_of(chip, struct apple_pwm, chip);
> +	if (state->enabled) {
> +		on_cycles = mul_u64_u64_div_u64(fpwm->clkrate,
> +						state->duty_cycle, NSEC_PER_SEC);
> +		off_cycles = mul_u64_u64_div_u64(fpwm->clkrate,
> +						 state->period, NSEC_PER_SEC) -
> on_cycles;
> +		writel(on_cycles, fpwm->base + PWM_ON_CYCLES);
> +		writel(off_cycles, fpwm->base + PWM_OFF_CYCLES);
> +		writel(CTRL_ENABLE | CTRL_OUTPUT_ENABLE | CTRL_UPDATE,
> +		       fpwm->base + PWM_CONTROL);
> +	} else {
> +		writel(0, fpwm->base + PWM_CONTROL);
> +	}
> +	return 0;
> +}
> +
> +static void apple_pwm_get_state(struct pwm_chip *chip, struct
> pwm_device *pwm,
> +			   struct pwm_state *state)
> +{
> +	struct apple_pwm *fpwm;
> +	u32 on_cycles, off_cycles, ctrl;
> +
> +	fpwm = container_of(chip, struct apple_pwm, chip);
> +
> +	ctrl = readl(fpwm->base + PWM_CONTROL);
> +	on_cycles = readl(fpwm->base + PWM_ON_CYCLES);
> +	off_cycles = readl(fpwm->base + PWM_OFF_CYCLES);
> +
> +	state->enabled = (ctrl & CTRL_ENABLE) && (ctrl &
> CTRL_OUTPUT_ENABLE);
> +	state->polarity = PWM_POLARITY_NORMAL;
> +	state->duty_cycle = div_u64(on_cycles, fpwm->clkrate) *
> NSEC_PER_SEC;
> +	state->period = div_u64(off_cycles + on_cycles, fpwm->clkrate) *
> +NSEC_PER_SEC; }
> +
> +static const struct pwm_ops apple_pwm_ops = {
> +	.apply = apple_pwm_apply,
> +	.get_state = apple_pwm_get_state,
> +	.owner = THIS_MODULE,
> +};
> +
> +static int apple_pwm_probe(struct platform_device *pdev) {
> +	struct apple_pwm *pwm;
> +	struct clk *clk;
> +	int ret;
> +
> +	pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
> +	if (!pwm)
> +		return -ENOMEM;
> +
> +	pwm->base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(pwm->base))
> +		return PTR_ERR(pwm->base);
> +
> +	platform_set_drvdata(pdev, pwm);
> +
> +	clk = devm_clk_get_enabled(&pdev->dev, NULL);
> +	if (IS_ERR(clk))
> +		return PTR_ERR(clk);

What is your use case? 

PWM is configured by bootloader intially??

Or

PWM is configured by Linux not by the bootloader?


Or

Driver needs to support both ??

Cheers,
Biju


> +
> +	pwm->clkrate = clk_get_rate(clk);
> +	pwm->chip.dev = &pdev->dev;
> +	pwm->chip.npwm = 1;
> +	pwm->chip.ops = &apple_pwm_ops;
> +
> +	ret = devm_pwmchip_add(&pdev->dev, &pwm->chip);
> +	return ret;
> +}
> +
> +static const struct of_device_id apple_pwm_of_match[] = {
> +	{ .compatible = "apple,s5l-fpwm" },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, apple_pwm_of_match);
> +
> +static struct platform_driver apple_pwm_driver = {
> +	.probe = apple_pwm_probe,
> +	.driver = {
> +		.name = "apple-pwm",
> +		.owner = THIS_MODULE,
> +		.of_match_table = apple_pwm_of_match,
> +	},
> +};
> +module_platform_driver(apple_pwm_driver);
> +
> +MODULE_DESCRIPTION("Apple SoC PWM driver"); MODULE_LICENSE("Dual
> +MIT/GPL");
> --
> 2.37.3
> 
> 
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Re: [PATCH v2 2/4] pwm: Add Apple PWM controller

[Sasha Finkelstein]

On Wed, 2 Nov 2022 at 18:33, Biju Das <biju.das.jz@bp.renesas.com> wrote:
> > +     clk = devm_clk_get_enabled(&pdev->dev, NULL);
> > +     if (IS_ERR(clk))
> > +             return PTR_ERR(clk);
>
> What is your use case?
>
> PWM is configured by bootloader intially??
>
> Or
>
> PWM is configured by Linux not by the bootloader?
>
> Or
>
> Driver needs to support both ??

The PWM device itself is configured by linux, but the clock it uses is
the systemwide 24 MHz clock, and that is configured by platform
firmware.

RE: [PATCH v2 2/4] pwm: Add Apple PWM controller

[Biju Das]

> Subject: Re: [PATCH v2 2/4] pwm: Add Apple PWM controller
> 
> On Wed, 2 Nov 2022 at 18:33, Biju Das <biju.das.jz@bp.renesas.com>
> wrote:
> > > +     clk = devm_clk_get_enabled(&pdev->dev, NULL);
> > > +     if (IS_ERR(clk))
> > > +             return PTR_ERR(clk);
> >
> > What is your use case?
> >
> > PWM is configured by bootloader intially??
> >
> > Or
> >
> > PWM is configured by Linux not by the bootloader?
> >
> > Or
> >
> > Driver needs to support both ??
> 
> The PWM device itself is configured by linux, but the clock it uses is
> the systemwide 24 MHz clock, and that is configured by platform
> firmware.

I just asked, because you are unnecessarily turning on the clock or increasing the usage
Count, even if it is not used by anyone during probe.

Cheers,
Biju

Re: [PATCH v2 2/4] pwm: Add Apple PWM controller

[Sasha Finkelstein]

On Wed, 2 Nov 2022 at 19:02, Biju Das <biju.das.jz@bp.renesas.com> wrote:

> I just asked, because you are unnecessarily turning on the clock or increasing the usage
> Count, even if it is not used by anyone during probe.

It is used to get the clock rate so it can be used to convert between
seconds and pwm ticks, and the pwm uses that clock, so it is kept
enabled while the pwm is active.

RE: [PATCH v2 2/4] pwm: Add Apple PWM controller

[Biju Das]

> Subject: Re: [PATCH v2 2/4] pwm: Add Apple PWM controller
> 
> On Wed, 2 Nov 2022 at 19:02, Biju Das <biju.das.jz@bp.renesas.com>
> wrote:
> 
> > I just asked, because you are unnecessarily turning on the clock or
> > increasing the usage Count, even if it is not used by anyone during
> probe.
> 
> It is used to get the clock rate so it can be used to convert between
> seconds and pwm ticks, and the pwm uses that clock, so it is kept
> enabled while the pwm is active.

You don't need to enable the pwm clock for getting the clock rate.
devm_clk_get() and then get the rate.

Then enable the clk whenever pwm is enabled
And disable the clk whenever pwm is disabled.

Cheers,
Biju

Re: [PATCH v2 2/4] pwm: Add Apple PWM controller

[Sasha Finkelstein]

On Wed, 2 Nov 2022 at 19:29, Biju Das <biju.das.jz@bp.renesas.com> wrote:
>
> Then enable the clk whenever pwm is enabled
> And disable the clk whenever pwm is disabled.
I can do that, but I do not see the point in doing that. This clock is
active whenever the system is turned on, all this will result in is
some unnecessary clock refcount increments/decrements.

RE: [PATCH v2 2/4] pwm: Add Apple PWM controller

[Biju Das]

> Subject: Re: [PATCH v2 2/4] pwm: Add Apple PWM controller
> 
> On Wed, 2 Nov 2022 at 19:29, Biju Das <biju.das.jz@bp.renesas.com>
> wrote:
> >
> > Then enable the clk whenever pwm is enabled And disable the clk
> > whenever pwm is disabled.
> I can do that, but I do not see the point in doing that. This clock is
> active whenever the system is turned on, all this will result in is
> some unnecessary clock refcount increments/decrements.

OK for me, as I do not know about your system. I just pointed out 
you are unnecessarily turning on the clock during probe
even if the pwm is not used.

Cheers,
Biju

[PATCH v2 3/4] arm64: dts: apple: t8103: Add PWM controller

[Sasha Finkelstein]

Adds PWM controller and keyboard backlight bindings for M1 MacBooks

Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com>
---
 arch/arm64/boot/dts/apple/t8103-j293.dts | 20 ++++++++++++++++++++
 arch/arm64/boot/dts/apple/t8103-j313.dts | 20 ++++++++++++++++++++
 arch/arm64/boot/dts/apple/t8103.dtsi     |  9 +++++++++
 3 files changed, 49 insertions(+)

diff --git a/arch/arm64/boot/dts/apple/t8103-j293.dts b/arch/arm64/boot/dts/apple/t8103-j293.dts
index ecb10d237a05..0b4b7e8e0726 100644
--- a/arch/arm64/boot/dts/apple/t8103-j293.dts
+++ b/arch/arm64/boot/dts/apple/t8103-j293.dts
@@ -11,6 +11,7 @@
 
 #include "t8103.dtsi"
 #include "t8103-jxxx.dtsi"
+#include <dt-bindings/leds/common.h>
 
 / {
 	compatible = "apple,j293", "apple,t8103", "apple,arm-platform";
@@ -43,3 +44,22 @@ &i2c2 {
 &i2c4 {
 	status = "okay";
 };
+
+/ {
+	led-controller {
+		compatible = "pwm-leds";
+		led-0 {
+			pwms = <&fpwm1 0 40000>;
+			pwm-names = "kbd-backlight";
+			label = "kbd_backlight";
+			function = LED_FUNCTION_KBD_BACKLIGHT;
+			color = <LED_COLOR_ID_WHITE>;
+			max-brightness = <255>;
+			default-state = "keep";
+		};
+	};
+};
+
+&fpwm1 {
+	status = "okay";
+};
diff --git a/arch/arm64/boot/dts/apple/t8103-j313.dts b/arch/arm64/boot/dts/apple/t8103-j313.dts
index df741737b8e6..0e0f57dee96b 100644
--- a/arch/arm64/boot/dts/apple/t8103-j313.dts
+++ b/arch/arm64/boot/dts/apple/t8103-j313.dts
@@ -11,6 +11,7 @@
 
 #include "t8103.dtsi"
 #include "t8103-jxxx.dtsi"
+#include <dt-bindings/leds/common.h>
 
 / {
 	compatible = "apple,j313", "apple,t8103", "apple,arm-platform";
@@ -35,3 +36,22 @@ &pcie0_dart_2 {
 
 /delete-node/ &port01;
 /delete-node/ &port02;
+
+/ {
+	led-controller {
+		compatible = "pwm-leds";
+		led-0 {
+			pwms = <&fpwm1 0 40000>;
+			pwm-names = "kbd-backlight";
+			label = "kbd_backlight";
+			function = LED_FUNCTION_KBD_BACKLIGHT;
+			color = <LED_COLOR_ID_WHITE>;
+			max-brightness = <255>;
+			default-state = "keep";
+		};
+	};
+};
+
+&fpwm1 {
+	status = "okay";
+};
diff --git a/arch/arm64/boot/dts/apple/t8103.dtsi b/arch/arm64/boot/dts/apple/t8103.dtsi
index 51a63b29d404..ccdb26ef6b22 100644
--- a/arch/arm64/boot/dts/apple/t8103.dtsi
+++ b/arch/arm64/boot/dts/apple/t8103.dtsi
@@ -191,6 +191,15 @@ i2c4: i2c@235020000 {
 			status = "disabled"; /* only used in J293 */
 		};
 
+		fpwm1: pwm@235044000 {
+			compatible = "apple,t8103-fpwm", "apple,s5l-fpwm";
+			reg = <0x2 0x35044000 0x0 0x4000>;
+			power-domains = <&ps_fpwm1>;
+			clocks = <&clkref>;
+			#pwm-cells = <2>;
+			status = "disabled";
+		};
+
 		serial0: serial@235200000 {
 			compatible = "apple,s5l-uart";
 			reg = <0x2 0x35200000 0x0 0x1000>;
-- 
2.37.3

[PATCH v2 4/4] MAINTAINERS: Add entries for Apple PWM driver

[Sasha Finkelstein]

Add the MAINTAINERS entries for the driver

Signed-off-by: Sasha Finkelstein <fnkl.kernel@gmail.com>
---
 MAINTAINERS | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 379945f82a64..414812941714 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1908,6 +1908,7 @@ F:	Documentation/devicetree/bindings/nvmem/apple,efuses.yaml
 F:	Documentation/devicetree/bindings/pci/apple,pcie.yaml
 F:	Documentation/devicetree/bindings/pinctrl/apple,pinctrl.yaml
 F:	Documentation/devicetree/bindings/power/apple*
+F:	Documentation/devicetree/bindings/pwm/apple,s5l-fpwm.yaml
 F:	Documentation/devicetree/bindings/watchdog/apple,wdt.yaml
 F:	arch/arm64/boot/dts/apple/
 F:	drivers/clk/clk-apple-nco.c
@@ -1921,6 +1922,7 @@ F:	drivers/mailbox/apple-mailbox.c
 F:	drivers/nvme/host/apple.c
 F:	drivers/nvmem/apple-efuses.c
 F:	drivers/pinctrl/pinctrl-apple-gpio.c
+F:	drivers/pwm/pwm-apple.c
 F:	drivers/soc/apple/*
 F:	drivers/watchdog/apple_wdt.c
 F:	include/dt-bindings/interrupt-controller/apple-aic.h
-- 
2.37.3

Re: [PATCH v2 0/4] PWM and keyboard backlight driver for ARM Macs

[Sven Peter]

Hi,

On Wed, Nov 2, 2022, at 15:15, Sasha Finkelstein wrote:
> Hi,
>
> This is the v2 of the patch series to add PWM and keyboard backlight
> drivers for ARM macs. The changes from v1 address the review
> comments on that patch set.
>
> v1: https://www.spinics.net/lists/linux-pwm/msg19500.html
>
> Best Regards.
>
> Sasha Finkelstein (4):
>   dt-bindings: pwm: Add Apple PWM controller
>   pwm: Add Apple PWM controller
>   arm64: dts: apple: t8103: Add PWM controller
>   MAINTAINERS: Add entries for Apple PWM driver
>
>  .../bindings/pwm/apple,s5l-fpwm.yaml          |  51 +++++++
>  MAINTAINERS                                   |   2 +
>  arch/arm64/boot/dts/apple/t8103-j293.dts      |  20 +++
>  arch/arm64/boot/dts/apple/t8103-j313.dts      |  20 +++
>  arch/arm64/boot/dts/apple/t8103.dtsi          |   9 ++
>  drivers/pwm/Kconfig                           |  12 ++
>  drivers/pwm/Makefile                          |   1 +
>  drivers/pwm/pwm-apple.c                       | 127 ++++++++++++++++++
>  8 files changed, 242 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/pwm/apple,s5l-fpwm.yaml
>  create mode 100644 drivers/pwm/pwm-apple.c
>
> -- 
> 2.37.3

this looks good to me, entire series:

Acked-by: Sven Peter <sven@svenpeter.dev>


Best,


Sven