* [PATCH v2 1/3] dt-bindings: leds: backlight: apple,dwi-bl: Add bindings for Apple DWI backlight
2024-12-07 13:03 [PATCH v2 0/3] Apple DWI backlight driver Nick Chan
@ 2024-12-07 13:03 ` Nick Chan
2024-12-09 9:16 ` Krzysztof Kozlowski
2024-12-07 13:03 ` [PATCH v2 2/3] backlight: dwi_bl: Add Apple DWI backlight driver Nick Chan
2024-12-07 13:03 ` [PATCH v2 3/3] MAINTAINERS: Add entries for Apple DWI backlight controller Nick Chan
2 siblings, 1 reply; 9+ messages in thread
From: Nick Chan @ 2024-12-07 13:03 UTC (permalink / raw)
To: Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Helge Deller, Hector Martin,
Sven Peter, Alyssa Rosenzweig, Nick Chan, dri-devel, linux-leds,
devicetree, linux-kernel, linux-fbdev, asahi, linux-arm-kernel
Add the device tree bindings for backlight controllers attached via Apple
DWI 2-wire interface.
Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
.../bindings/leds/backlight/apple,dwi-bl.yaml | 54 +++++++++++++++++++
1 file changed, 54 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml
diff --git a/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml b/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml
new file mode 100644
index 000000000000..9d4aa243f679
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml
@@ -0,0 +1,54 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/backlight/apple,dwi-bl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple DWI 2-Wire Interface Backlight Controller
+
+maintainers:
+ - Nick Chan <towinchenmi@gmail.com>
+
+description: |
+ Apple SoCs contain a 2-wire interface called DWI. On some Apple iPhones,
+ iPads and iPod touches with a LCD display, 1-2 backlight controllers
+ are connected via DWI. Interfacing with DWI controls all backlight
+ controllers at the same time. As such, the backlight controllers are
+ treated as a single controller regardless of the underlying
+ configuration.
+
+properties:
+ compatible:
+ items:
+ - enum:
+ - apple,s5l8960x-dwi-bl
+ - apple,t7000-dwi-bl
+ - apple,s8000-dwi-bl
+ - apple,t8010-dwi-bl
+ - apple,t8015-dwi-bl
+ - const: apple,dwi-bl
+
+ reg:
+ maxItems: 1
+
+ power-domains:
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ soc {
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ dwi_bl: backlight@20e200010 {
+ compatible = "apple,s5l8960x-dwi-bl", "apple,dwi-bl";
+ reg = <0x2 0x0e200010 0 8>;
+ power-domains = <&ps_dwi>;
+ };
+ };
--
2.47.1
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH v2 1/3] dt-bindings: leds: backlight: apple,dwi-bl: Add bindings for Apple DWI backlight
2024-12-07 13:03 ` [PATCH v2 1/3] dt-bindings: leds: backlight: apple,dwi-bl: Add bindings for Apple DWI backlight Nick Chan
@ 2024-12-09 9:16 ` Krzysztof Kozlowski
2024-12-09 11:07 ` Nick Chan
0 siblings, 1 reply; 9+ messages in thread
From: Krzysztof Kozlowski @ 2024-12-09 9:16 UTC (permalink / raw)
To: Nick Chan
Cc: Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Helge Deller, Hector Martin,
Sven Peter, Alyssa Rosenzweig, dri-devel, linux-leds, devicetree,
linux-kernel, linux-fbdev, asahi, linux-arm-kernel
On Sat, Dec 07, 2024 at 09:03:14PM +0800, Nick Chan wrote:
> Add the device tree bindings for backlight controllers attached via Apple
> DWI 2-wire interface.
A nit, subject: drop second/last, redundant "bindings for". The
"dt-bindings" prefix is already stating that these are bindings.
See also:
https://elixir.bootlin.com/linux/v6.7-rc8/source/Documentation/devicetree/bindings/submitting-patches.rst#L18
>
> Signed-off-by: Nick Chan <towinchenmi@gmail.com>
> ---
> .../bindings/leds/backlight/apple,dwi-bl.yaml | 54 +++++++++++++++++++
> 1 file changed, 54 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml
>
> diff --git a/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml b/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml
> new file mode 100644
> index 000000000000..9d4aa243f679
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/backlight/apple,dwi-bl.yaml
> @@ -0,0 +1,54 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/leds/backlight/apple,dwi-bl.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Apple DWI 2-Wire Interface Backlight Controller
> +
> +maintainers:
> + - Nick Chan <towinchenmi@gmail.com>
> +
> +description: |
Do not need '|' unless you need to preserve formatting.
> + Apple SoCs contain a 2-wire interface called DWI. On some Apple iPhones,
> + iPads and iPod touches with a LCD display, 1-2 backlight controllers
> + are connected via DWI. Interfacing with DWI controls all backlight
> + controllers at the same time. As such, the backlight controllers are
> + treated as a single controller regardless of the underlying
> + configuration.
> +
missing allOf: with $ref to common.yaml
> +properties:
> + compatible:
> + items:
> + - enum:
> + - apple,s5l8960x-dwi-bl
> + - apple,t7000-dwi-bl
> + - apple,s8000-dwi-bl
> + - apple,t8010-dwi-bl
> + - apple,t8015-dwi-bl
> + - const: apple,dwi-bl
> +
> + reg:
> + maxItems: 1
> +
> + power-domains:
> + maxItems: 1
> +
> +required:
> + - compatible
> + - reg
> +
> +additionalProperties: false
(and this then becomes unevaluatedProperties: false)
> +
> +examples:
> + - |
> + soc {
> + #address-cells = <2>;
> + #size-cells = <2>;
> +
> + dwi_bl: backlight@20e200010 {
> + compatible = "apple,s5l8960x-dwi-bl", "apple,dwi-bl";
> + reg = <0x2 0x0e200010 0 8>;
Usual preference is to keep hex everywhere.
Best regards,
Krzysztof
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH v2 1/3] dt-bindings: leds: backlight: apple,dwi-bl: Add bindings for Apple DWI backlight
2024-12-09 9:16 ` Krzysztof Kozlowski
@ 2024-12-09 11:07 ` Nick Chan
0 siblings, 0 replies; 9+ messages in thread
From: Nick Chan @ 2024-12-09 11:07 UTC (permalink / raw)
To: Krzysztof Kozlowski
Cc: Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Helge Deller, Hector Martin,
Sven Peter, Alyssa Rosenzweig, dri-devel, linux-leds, devicetree,
linux-kernel, linux-fbdev, asahi, linux-arm-kernel
On 9/12/2024 17:16, Krzysztof Kozlowski wrote:
> On Sat, Dec 07, 2024 at 09:03:14PM +0800, Nick Chan wrote:
>> Add the device tree bindings for backlight controllers attached via Apple
>> DWI 2-wire interface.
[...]
Ack all the changes, will be in v4.
Nick Chan
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v2 2/3] backlight: dwi_bl: Add Apple DWI backlight driver
2024-12-07 13:03 [PATCH v2 0/3] Apple DWI backlight driver Nick Chan
2024-12-07 13:03 ` [PATCH v2 1/3] dt-bindings: leds: backlight: apple,dwi-bl: Add bindings for Apple DWI backlight Nick Chan
@ 2024-12-07 13:03 ` Nick Chan
2024-12-09 9:22 ` Krzysztof Kozlowski
2024-12-07 13:03 ` [PATCH v2 3/3] MAINTAINERS: Add entries for Apple DWI backlight controller Nick Chan
2 siblings, 1 reply; 9+ messages in thread
From: Nick Chan @ 2024-12-07 13:03 UTC (permalink / raw)
To: Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Helge Deller, Hector Martin,
Sven Peter, Alyssa Rosenzweig, Nick Chan, dri-devel, linux-leds,
devicetree, linux-kernel, linux-fbdev, asahi, linux-arm-kernel
Add driver for backlight controllers attached via Apple DWI 2-wire
interface, which is found on some Apple iPhones, iPads and iPod touches
with a LCD display.
Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
drivers/video/backlight/Kconfig | 12 +++
drivers/video/backlight/Makefile | 1 +
drivers/video/backlight/dwi_bl.c | 124 +++++++++++++++++++++++++++++++
3 files changed, 137 insertions(+)
create mode 100644 drivers/video/backlight/dwi_bl.c
diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 3614a5d29c71..e64cc3d51ac5 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -166,6 +166,18 @@ config BACKLIGHT_EP93XX
To compile this driver as a module, choose M here: the module will
be called ep93xx_bl.
+config BACKLIGHT_APPLE_DWI
+ tristate "Apple DWI 2-Wire Interface Backlight Driver"
+ depends on ARCH_APPLE || COMPILE_TEST
+ default y
+ help
+ Say Y to enable the backlight driver for backlight controllers
+ attached via the Apple DWI 2-wire interface which is found in some
+ Apple iPhones, iPads and iPod touches.
+
+ To compile this driver as a module, choose M here: the module will
+ be called dwi_bl.
+
config BACKLIGHT_IPAQ_MICRO
tristate "iPAQ microcontroller backlight driver"
depends on MFD_IPAQ_MICRO
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index 8fc98f760a8a..0a569d7f0210 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_BACKLIGHT_BD6107) += bd6107.o
obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o
obj-$(CONFIG_BACKLIGHT_DA903X) += da903x_bl.o
obj-$(CONFIG_BACKLIGHT_DA9052) += da9052_bl.o
+obj-$(CONFIG_BACKLIGHT_APPLE_DWI) += dwi_bl.o
obj-$(CONFIG_BACKLIGHT_EP93XX) += ep93xx_bl.o
obj-$(CONFIG_BACKLIGHT_GPIO) += gpio_backlight.o
obj-$(CONFIG_BACKLIGHT_HP680) += hp680_bl.o
diff --git a/drivers/video/backlight/dwi_bl.c b/drivers/video/backlight/dwi_bl.c
new file mode 100644
index 000000000000..d4bfd74b3129
--- /dev/null
+++ b/drivers/video/backlight/dwi_bl.c
@@ -0,0 +1,124 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/*
+ * Driver for backlight controllers attached via Apple DWI 2-wire interface
+ *
+ * Copyright (c) 2024 Nick Chan <towinchenmi@gmail.com>
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/backlight.h>
+
+#define DWI_BL_CTL 0x0
+#define DWI_BL_CTL_SEND1 BIT(0)
+#define DWI_BL_CTL_SEND2 BIT(4)
+#define DWI_BL_CTL_SEND3 BIT(5)
+#define DWI_BL_CTL_LE_DATA BIT(6)
+/* Only used on Apple A9 and later */
+#define DWI_BL_CTL_SEND4 BIT(12)
+
+#define DWI_BL_CMD 0x4
+#define DWI_BL_CMD_TYPE GENMASK(31, 28)
+#define DWI_BL_CMD_TYPE_SET_BRIGHTNESS 0xa
+#define DWI_BL_CMD_DATA GENMASK(10, 0)
+
+#define DWI_BL_CTL_SEND (DWI_BL_CTL_SEND1 | \
+ DWI_BL_CTL_SEND2 | \
+ DWI_BL_CTL_SEND3 | \
+ DWI_BL_CTL_LE_DATA | \
+ DWI_BL_CTL_SEND4)
+
+#define DWI_BL_MAX_BRIGHTNESS 2047
+
+struct apple_dwi_bl {
+ void __iomem *base;
+};
+
+static int dwi_bl_update_status(struct backlight_device *bl)
+{
+ struct apple_dwi_bl *dwi_bl = bl_get_data(bl);
+
+ int brightness = backlight_get_brightness(bl);
+
+ u32 cmd = 0;
+
+ cmd |= FIELD_PREP(DWI_BL_CMD_DATA, brightness);
+ cmd |= FIELD_PREP(DWI_BL_CMD_TYPE, DWI_BL_CMD_TYPE_SET_BRIGHTNESS);
+
+ writel(cmd, dwi_bl->base + DWI_BL_CMD);
+ writel(DWI_BL_CTL_SEND, dwi_bl->base + DWI_BL_CTL);
+
+ return 0;
+}
+
+static int dwi_bl_get_brightness(struct backlight_device *bl)
+{
+ struct apple_dwi_bl *dwi_bl = bl_get_data(bl);
+
+ u32 cmd = readl(dwi_bl->base + DWI_BL_CMD);
+
+ return FIELD_GET(DWI_BL_CMD_DATA, cmd);
+}
+
+static const struct backlight_ops dwi_bl_ops = {
+ .options = BL_CORE_SUSPENDRESUME,
+ .get_brightness = dwi_bl_get_brightness,
+ .update_status = dwi_bl_update_status
+};
+
+static int dwi_bl_probe(struct platform_device *dev)
+{
+ struct apple_dwi_bl *dwi_bl;
+ struct backlight_device *bl;
+ struct backlight_properties props;
+ struct resource *res;
+
+ dwi_bl = devm_kzalloc(&dev->dev, sizeof(struct apple_dwi_bl), GFP_KERNEL);
+ if (!dwi_bl)
+ return -ENOMEM;
+
+ res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENXIO;
+
+ dwi_bl->base = devm_ioremap_resource(&dev->dev, res);
+ if (IS_ERR(dwi_bl->base))
+ return PTR_ERR(dwi_bl->base);
+
+ memset(&props, 0, sizeof(struct backlight_properties));
+ props.type = BACKLIGHT_RAW;
+ props.max_brightness = DWI_BL_MAX_BRIGHTNESS;
+
+ bl = devm_backlight_device_register(&dev->dev, dev->name, &dev->dev,
+ dwi_bl, &dwi_bl_ops, &props);
+ if (IS_ERR(bl))
+ return PTR_ERR(bl);
+
+ platform_set_drvdata(dev, dwi_bl);
+
+ bl->props.brightness = dwi_bl_get_brightness(bl);
+
+ return 0;
+}
+
+static const struct of_device_id dwi_bl_of_match[] = {
+ { .compatible = "apple,dwi-bl" },
+ {},
+};
+
+MODULE_DEVICE_TABLE(of, dwi_bl_of_match);
+
+static struct platform_driver dwi_bl_driver = {
+ .driver = {
+ .name = "dwi-bl",
+ .of_match_table = dwi_bl_of_match
+ },
+ .probe = dwi_bl_probe,
+};
+
+module_platform_driver(dwi_bl_driver);
+
+MODULE_DESCRIPTION("Apple DWI Backlight Driver");
+MODULE_AUTHOR("Nick Chan <towinchenmi@gmail.com>");
+MODULE_LICENSE("Dual MIT/GPL");
--
2.47.1
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH v2 2/3] backlight: dwi_bl: Add Apple DWI backlight driver
2024-12-07 13:03 ` [PATCH v2 2/3] backlight: dwi_bl: Add Apple DWI backlight driver Nick Chan
@ 2024-12-09 9:22 ` Krzysztof Kozlowski
2024-12-09 10:07 ` Nick Chan
2024-12-09 10:22 ` Nick Chan
0 siblings, 2 replies; 9+ messages in thread
From: Krzysztof Kozlowski @ 2024-12-09 9:22 UTC (permalink / raw)
To: Nick Chan, y
Cc: Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Helge Deller, Hector Martin,
Sven Peter, Alyssa Rosenzweig, dri-devel, linux-leds, devicetree,
linux-kernel, linux-fbdev, asahi, linux-arm-kernel
On Sat, Dec 07, 2024 at 09:03:15PM +0800, Nick Chan wrote:
> Add driver for backlight controllers attached via Apple DWI 2-wire
> interface, which is found on some Apple iPhones, iPads and iPod touches
> with a LCD display.
>
> Signed-off-by: Nick Chan <towinchenmi@gmail.com>
> ---
> drivers/video/backlight/Kconfig | 12 +++
> drivers/video/backlight/Makefile | 1 +
> drivers/video/backlight/dwi_bl.c | 124 +++++++++++++++++++++++++++++++
> 3 files changed, 137 insertions(+)
> create mode 100644 drivers/video/backlight/dwi_bl.c
>
> diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
> index 3614a5d29c71..e64cc3d51ac5 100644
> --- a/drivers/video/backlight/Kconfig
> +++ b/drivers/video/backlight/Kconfig
> @@ -166,6 +166,18 @@ config BACKLIGHT_EP93XX
> To compile this driver as a module, choose M here: the module will
> be called ep93xx_bl.
>
> +config BACKLIGHT_APPLE_DWI
> + tristate "Apple DWI 2-Wire Interface Backlight Driver"
> + depends on ARCH_APPLE || COMPILE_TEST
> + default y
> + help
> + Say Y to enable the backlight driver for backlight controllers
> + attached via the Apple DWI 2-wire interface which is found in some
> + Apple iPhones, iPads and iPod touches.
Mixed/messed indentation. Some spaces?
> +
> + To compile this driver as a module, choose M here: the module will
> + be called dwi_bl.
> +
> config BACKLIGHT_IPAQ_MICRO
> tristate "iPAQ microcontroller backlight driver"
> depends on MFD_IPAQ_MICRO
> diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
> index 8fc98f760a8a..0a569d7f0210 100644
> --- a/drivers/video/backlight/Makefile
> +++ b/drivers/video/backlight/Makefile
> @@ -28,6 +28,7 @@ obj-$(CONFIG_BACKLIGHT_BD6107) += bd6107.o
> obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o
> obj-$(CONFIG_BACKLIGHT_DA903X) += da903x_bl.o
> obj-$(CONFIG_BACKLIGHT_DA9052) += da9052_bl.o
> +obj-$(CONFIG_BACKLIGHT_APPLE_DWI) += dwi_bl.o
Please do not introduce other sorting way - it is sorted by config name.
Which will also point you to apple_bl.o and need of explaining the
differences, e.g. why this cannot be one driver.
> obj-$(CONFIG_BACKLIGHT_EP93XX) += ep93xx_bl.o
> obj-$(CONFIG_BACKLIGHT_GPIO) += gpio_backlight.o
> obj-$(CONFIG_BACKLIGHT_HP680) += hp680_bl.o
> diff --git a/drivers/video/backlight/dwi_bl.c b/drivers/video/backlight/dwi_bl.c
> new file mode 100644
> index 000000000000..d4bfd74b3129
> --- /dev/null
> +++ b/drivers/video/backlight/dwi_bl.c
> @@ -0,0 +1,124 @@
> +// SPDX-License-Identifier: GPL-2.0 OR MIT
> +/*
> + * Driver for backlight controllers attached via Apple DWI 2-wire interface
> + *
> + * Copyright (c) 2024 Nick Chan <towinchenmi@gmail.com>
> + */
> +
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/io.h>
> +#include <linux/backlight.h>
> +
> +#define DWI_BL_CTL 0x0
> +#define DWI_BL_CTL_SEND1 BIT(0)
> +#define DWI_BL_CTL_SEND2 BIT(4)
> +#define DWI_BL_CTL_SEND3 BIT(5)
> +#define DWI_BL_CTL_LE_DATA BIT(6)
> +/* Only used on Apple A9 and later */
> +#define DWI_BL_CTL_SEND4 BIT(12)
> +
> +#define DWI_BL_CMD 0x4
> +#define DWI_BL_CMD_TYPE GENMASK(31, 28)
> +#define DWI_BL_CMD_TYPE_SET_BRIGHTNESS 0xa
> +#define DWI_BL_CMD_DATA GENMASK(10, 0)
> +
> +#define DWI_BL_CTL_SEND (DWI_BL_CTL_SEND1 | \
> + DWI_BL_CTL_SEND2 | \
> + DWI_BL_CTL_SEND3 | \
> + DWI_BL_CTL_LE_DATA | \
> + DWI_BL_CTL_SEND4)
> +
> +#define DWI_BL_MAX_BRIGHTNESS 2047
> +
> +struct apple_dwi_bl {
> + void __iomem *base;
> +};
> +
> +static int dwi_bl_update_status(struct backlight_device *bl)
> +{
> + struct apple_dwi_bl *dwi_bl = bl_get_data(bl);
> +
> + int brightness = backlight_get_brightness(bl);
> +
> + u32 cmd = 0;
> +
> + cmd |= FIELD_PREP(DWI_BL_CMD_DATA, brightness);
> + cmd |= FIELD_PREP(DWI_BL_CMD_TYPE, DWI_BL_CMD_TYPE_SET_BRIGHTNESS);
> +
> + writel(cmd, dwi_bl->base + DWI_BL_CMD);
> + writel(DWI_BL_CTL_SEND, dwi_bl->base + DWI_BL_CTL);
> +
> + return 0;
> +}
> +
> +static int dwi_bl_get_brightness(struct backlight_device *bl)
> +{
> + struct apple_dwi_bl *dwi_bl = bl_get_data(bl);
> +
> + u32 cmd = readl(dwi_bl->base + DWI_BL_CMD);
> +
> + return FIELD_GET(DWI_BL_CMD_DATA, cmd);
> +}
> +
> +static const struct backlight_ops dwi_bl_ops = {
> + .options = BL_CORE_SUSPENDRESUME,
> + .get_brightness = dwi_bl_get_brightness,
> + .update_status = dwi_bl_update_status
> +};
> +
> +static int dwi_bl_probe(struct platform_device *dev)
> +{
> + struct apple_dwi_bl *dwi_bl;
> + struct backlight_device *bl;
> + struct backlight_properties props;
> + struct resource *res;
> +
> + dwi_bl = devm_kzalloc(&dev->dev, sizeof(struct apple_dwi_bl), GFP_KERNEL);
sizeof(*)
> + if (!dwi_bl)
> + return -ENOMEM;
> +
> + res = platform_get_resource(dev, IORESOURCE_MEM, 0);
> + if (!res)
> + return -ENXIO;
> +
> + dwi_bl->base = devm_ioremap_resource(&dev->dev, res);
Use helper for these two, devm_platform_get_and_ioremap_resource() or
similar.
Best regards,
Krzysztof
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH v2 2/3] backlight: dwi_bl: Add Apple DWI backlight driver
2024-12-09 9:22 ` Krzysztof Kozlowski
@ 2024-12-09 10:07 ` Nick Chan
2024-12-09 10:22 ` Nick Chan
1 sibling, 0 replies; 9+ messages in thread
From: Nick Chan @ 2024-12-09 10:07 UTC (permalink / raw)
To: Krzysztof Kozlowski, y
Cc: Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Helge Deller, Hector Martin,
Sven Peter, Alyssa Rosenzweig, dri-devel, linux-leds, devicetree,
linux-kernel, linux-fbdev, asahi, linux-arm-kernel
Krzysztof Kozlowski 於 2024/12/9 下午5:22 寫道:
> On Sat, Dec 07, 2024 at 09:03:15PM +0800, Nick Chan wrote:
>> Add driver for backlight controllers attached via Apple DWI 2-wire
>> interface, which is found on some Apple iPhones, iPads and iPod touches
>> with a LCD display.
>>
>> Signed-off-by: Nick Chan <towinchenmi@gmail.com>
>> ---
>> drivers/video/backlight/Kconfig | 12 +++
>> drivers/video/backlight/Makefile | 1 +
>> drivers/video/backlight/dwi_bl.c | 124 +++++++++++++++++++++++++++++++
>> 3 files changed, 137 insertions(+)
>> create mode 100644 drivers/video/backlight/dwi_bl.c
>>
>> diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
>> index 3614a5d29c71..e64cc3d51ac5 100644
>> --- a/drivers/video/backlight/Kconfig
>> +++ b/drivers/video/backlight/Kconfig
>> @@ -166,6 +166,18 @@ config BACKLIGHT_EP93XX
>> To compile this driver as a module, choose M here: the module will
>> be called ep93xx_bl.
>>
>> +config BACKLIGHT_APPLE_DWI
>> + tristate "Apple DWI 2-Wire Interface Backlight Driver"
>> + depends on ARCH_APPLE || COMPILE_TEST
>> + default y
>> + help
>> + Say Y to enable the backlight driver for backlight controllers
>> + attached via the Apple DWI 2-wire interface which is found in some
>> + Apple iPhones, iPads and iPod touches.
>
> Mixed/messed indentation. Some spaces?
Ack. Will be fixed for v4.
>
>> +
>> + To compile this driver as a module, choose M here: the module will
>> + be called dwi_bl.
>> +
>> config BACKLIGHT_IPAQ_MICRO
>> tristate "iPAQ microcontroller backlight driver"
>> depends on MFD_IPAQ_MICRO
>> diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
>> index 8fc98f760a8a..0a569d7f0210 100644
>> --- a/drivers/video/backlight/Makefile
>> +++ b/drivers/video/backlight/Makefile
>> @@ -28,6 +28,7 @@ obj-$(CONFIG_BACKLIGHT_BD6107) += bd6107.o
>> obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o
>> obj-$(CONFIG_BACKLIGHT_DA903X) += da903x_bl.o
>> obj-$(CONFIG_BACKLIGHT_DA9052) += da9052_bl.o
>> +obj-$(CONFIG_BACKLIGHT_APPLE_DWI) += dwi_bl.o
>
> Please do not introduce other sorting way - it is sorted by config name.
> Which will also point you to apple_bl.o and need of explaining the
> differences, e.g. why this cannot be one driver.
apple_bl is a driver backlight controllers on a PCI bus on Intel Macs,
which is
completely different from the Samsung-derived DWI block this driver
deals with.
This will be explained in the commit message for v4.
>
>
>> obj-$(CONFIG_BACKLIGHT_EP93XX) += ep93xx_bl.o
>> obj-$(CONFIG_BACKLIGHT_GPIO) += gpio_backlight.o
>> obj-$(CONFIG_BACKLIGHT_HP680) += hp680_bl.o
>> diff --git a/drivers/video/backlight/dwi_bl.c b/drivers/video/backlight/dwi_bl.c
>> new file mode 100644
>> index 000000000000..d4bfd74b3129
>> --- /dev/null
>> +++ b/drivers/video/backlight/dwi_bl.c
>> @@ -0,0 +1,124 @@
>> +// SPDX-License-Identifier: GPL-2.0 OR MIT
>> +/*
>> + * Driver for backlight controllers attached via Apple DWI 2-wire interface
>> + *
>> + * Copyright (c) 2024 Nick Chan <towinchenmi@gmail.com>
>> + */
>> +
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/io.h>
>> +#include <linux/backlight.h>
>> +
>> +#define DWI_BL_CTL 0x0
>> +#define DWI_BL_CTL_SEND1 BIT(0)
>> +#define DWI_BL_CTL_SEND2 BIT(4)
>> +#define DWI_BL_CTL_SEND3 BIT(5)
>> +#define DWI_BL_CTL_LE_DATA BIT(6)
>> +/* Only used on Apple A9 and later */
>> +#define DWI_BL_CTL_SEND4 BIT(12)
>> +
>> +#define DWI_BL_CMD 0x4
>> +#define DWI_BL_CMD_TYPE GENMASK(31, 28)
>> +#define DWI_BL_CMD_TYPE_SET_BRIGHTNESS 0xa
>> +#define DWI_BL_CMD_DATA GENMASK(10, 0)
>> +
>> +#define DWI_BL_CTL_SEND (DWI_BL_CTL_SEND1 | \
>> + DWI_BL_CTL_SEND2 | \
>> + DWI_BL_CTL_SEND3 | \
>> + DWI_BL_CTL_LE_DATA | \
>> + DWI_BL_CTL_SEND4)
>> +
>> +#define DWI_BL_MAX_BRIGHTNESS 2047
>> +
>> +struct apple_dwi_bl {
>> + void __iomem *base;
>> +};
>> +
>> +static int dwi_bl_update_status(struct backlight_device *bl)
>> +{
>> + struct apple_dwi_bl *dwi_bl = bl_get_data(bl);
>> +
>> + int brightness = backlight_get_brightness(bl);
>> +
>> + u32 cmd = 0;
>> +
>> + cmd |= FIELD_PREP(DWI_BL_CMD_DATA, brightness);
>> + cmd |= FIELD_PREP(DWI_BL_CMD_TYPE, DWI_BL_CMD_TYPE_SET_BRIGHTNESS);
>> +
>> + writel(cmd, dwi_bl->base + DWI_BL_CMD);
>> + writel(DWI_BL_CTL_SEND, dwi_bl->base + DWI_BL_CTL);
>> +
>> + return 0;
>> +}
>> +
>> +static int dwi_bl_get_brightness(struct backlight_device *bl)
>> +{
>> + struct apple_dwi_bl *dwi_bl = bl_get_data(bl);
>> +
>> + u32 cmd = readl(dwi_bl->base + DWI_BL_CMD);
>> +
>> + return FIELD_GET(DWI_BL_CMD_DATA, cmd);
>> +}
>> +
>> +static const struct backlight_ops dwi_bl_ops = {
>> + .options = BL_CORE_SUSPENDRESUME,
>> + .get_brightness = dwi_bl_get_brightness,
>> + .update_status = dwi_bl_update_status
>> +};
>> +
>> +static int dwi_bl_probe(struct platform_device *dev)
>> +{
>> + struct apple_dwi_bl *dwi_bl;
>> + struct backlight_device *bl;
>> + struct backlight_properties props;
>> + struct resource *res;
>> +
>> + dwi_bl = devm_kzalloc(&dev->dev, sizeof(struct apple_dwi_bl), GFP_KERNEL);
>
> sizeof(*)
>
>> + if (!dwi_bl)
>> + return -ENOMEM;
>> +
>> + res = platform_get_resource(dev, IORESOURCE_MEM, 0);
>> + if (!res)
>> + return -ENXIO;
>> +
>> + dwi_bl->base = devm_ioremap_resource(&dev->dev, res);
>
> Use helper for these two, devm_platform_get_and_ioremap_resource() or
> similar.
Ack. Will be fixed for v4.
>
> Best regards,
> Krzysztof
>
Nick Chan
^ permalink raw reply [flat|nested] 9+ messages in thread* Re: [PATCH v2 2/3] backlight: dwi_bl: Add Apple DWI backlight driver
2024-12-09 9:22 ` Krzysztof Kozlowski
2024-12-09 10:07 ` Nick Chan
@ 2024-12-09 10:22 ` Nick Chan
1 sibling, 0 replies; 9+ messages in thread
From: Nick Chan @ 2024-12-09 10:22 UTC (permalink / raw)
To: Krzysztof Kozlowski, y
Cc: Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Helge Deller, Hector Martin,
Sven Peter, Alyssa Rosenzweig, dri-devel, linux-leds, devicetree,
linux-kernel, linux-fbdev, asahi, linux-arm-kernel
Krzysztof Kozlowski 於 2024/12/9 下午5:22 寫道:
>> diff --git a/drivers/video/backlight/dwi_bl.c b/drivers/video/backlight/dwi_bl.c
>> new file mode 100644
>> index 000000000000..d4bfd74b3129
>> --- /dev/null
>> +++ b/drivers/video/backlight/dwi_bl.c
>> @@ -0,0 +1,124 @@
[...]
>> +
>> + dwi_bl = devm_kzalloc(&dev->dev, sizeof(struct apple_dwi_bl), GFP_KERNEL);
>
> sizeof(*)
Ack this change as well for v4.
>
>> + if (!dwi_bl)
>> + return -ENOMEM;
[...]
Nick Chan
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH v2 3/3] MAINTAINERS: Add entries for Apple DWI backlight controller
2024-12-07 13:03 [PATCH v2 0/3] Apple DWI backlight driver Nick Chan
2024-12-07 13:03 ` [PATCH v2 1/3] dt-bindings: leds: backlight: apple,dwi-bl: Add bindings for Apple DWI backlight Nick Chan
2024-12-07 13:03 ` [PATCH v2 2/3] backlight: dwi_bl: Add Apple DWI backlight driver Nick Chan
@ 2024-12-07 13:03 ` Nick Chan
2 siblings, 0 replies; 9+ messages in thread
From: Nick Chan @ 2024-12-07 13:03 UTC (permalink / raw)
To: Lee Jones, Daniel Thompson, Jingoo Han, Pavel Machek, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Helge Deller, Hector Martin,
Sven Peter, Alyssa Rosenzweig, Nick Chan, dri-devel, linux-leds,
devicetree, linux-kernel, linux-fbdev, asahi, linux-arm-kernel
Add MAINTAINERS entries for the driver.
Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---
MAINTAINERS | 2 ++
1 file changed, 2 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 1e930c7a58b1..36de76bc6fd4 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2204,6 +2204,7 @@ 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/video/backlight/apple,dwi-bl.yaml
F: Documentation/devicetree/bindings/watchdog/apple,wdt.yaml
F: arch/arm64/boot/dts/apple/
F: drivers/bluetooth/hci_bcm4377.c
@@ -2221,6 +2222,7 @@ 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/video/backlight/dwi_bl.c
F: drivers/watchdog/apple_wdt.c
F: include/dt-bindings/interrupt-controller/apple-aic.h
F: include/dt-bindings/pinctrl/apple.h
--
2.47.1
^ permalink raw reply related [flat|nested] 9+ messages in thread