* [PATCH v6 0/8] RTL8231 GPIO expander support
@ 2025-10-21 14:23 Sander Vanheule
2025-10-21 14:23 ` [PATCH v6 1/8] gpio: regmap: Force writes for aliased data regs Sander Vanheule
` (9 more replies)
0 siblings, 10 replies; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:23 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
The RTL8231 GPIO and LED expander can be configured for use as an MDIO
or SMI bus device. Currently only the MDIO mode is supported, although
SMI mode support should be fairly straightforward, once an SMI bus
driver is available.
Provided features by the RTL8231:
- Up to 37 GPIOs
- Configurable drive strength: 8mA or 4mA (currently unsupported)
- Input debouncing on GPIOs 31-36
- Up to 88 LEDs in multiple scan matrix groups
- On, off, or one of six toggling intervals
- "single-color mode": 2×36 single color LEDs + 8 bi-color LEDs
- "bi-color mode": (12 + 2×6) bi-color LEDs + 24 single color LEDs
- Up to one PWM output (currently unsupported)
- Fixed duty cycle, 8 selectable frequencies (1.2kHz - 4.8kHz)
The patches have been in use downstream by OpenWrt for some months. As
the original patches are already a few years old, I would like to request
all patches to be reviewed again (and I've dropped all provided tags and
changelogs).
---
RFC for gpio-regmap changes:
Link: https://lore.kernel.org/lkml/20251020115636.55417-1-sander@svanheule.net/
Patch series v5 (June 2021):
Link: https://lore.kernel.org/lkml/cover.1623532208.git.sander@svanheule.net/
Sander Vanheule (8):
gpio: regmap: Force writes for aliased data regs
gpio: regmap: Bypass cache for aliased inputs
dt-bindings: leds: Binding for RTL8231 scan matrix
dt-bindings: mfd: Binding for RTL8231
mfd: Add RTL8231 core device
pinctrl: Add RTL8231 pin control and GPIO support
leds: Add support for RTL8231 LED scan matrix
MAINTAINERS: Add RTL8231 MFD driver
.../bindings/leds/realtek,rtl8231-leds.yaml | 167 ++++++
.../bindings/mfd/realtek,rtl8231.yaml | 189 ++++++
MAINTAINERS | 10 +
drivers/gpio/gpio-regmap.c | 18 +-
drivers/leds/Kconfig | 10 +
drivers/leds/Makefile | 1 +
drivers/leds/leds-rtl8231.c | 285 ++++++++++
drivers/mfd/Kconfig | 9 +
drivers/mfd/Makefile | 1 +
drivers/mfd/rtl8231.c | 193 +++++++
drivers/pinctrl/Kconfig | 11 +
drivers/pinctrl/Makefile | 1 +
drivers/pinctrl/pinctrl-rtl8231.c | 538 ++++++++++++++++++
include/linux/mfd/rtl8231.h | 71 +++
14 files changed, 1500 insertions(+), 4 deletions(-)
create mode 100644 Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
create mode 100644 Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
create mode 100644 drivers/leds/leds-rtl8231.c
create mode 100644 drivers/mfd/rtl8231.c
create mode 100644 drivers/pinctrl/pinctrl-rtl8231.c
create mode 100644 include/linux/mfd/rtl8231.h
--
2.51.0
^ permalink raw reply [flat|nested] 22+ messages in thread
* [PATCH v6 1/8] gpio: regmap: Force writes for aliased data regs
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
@ 2025-10-21 14:23 ` Sander Vanheule
2025-10-21 14:23 ` [PATCH v6 2/8] gpio: regmap: Bypass cache for aliased inputs Sander Vanheule
` (8 subsequent siblings)
9 siblings, 0 replies; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:23 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
GPIO chips often have data input and output fields aliased to the same
offset. Since gpio-regmap performs a value update before the direction
update (to prevent glitches), a pin currently configured as input may
cause regmap_update_bits() to not perform a write.
This may cause unexpected line states when the current input state
equals the requested output state:
OUT IN OUT
DIR ''''''\...|.../''''''
pin ....../'''|'''\......
(1) (2) (3)
1. Line was configurad as out-low, but is reconfigured to input.
External logic results in high value.
2. Set output value high. regmap_update_bits() sees the value is
already high and discards the register write.
3. Line is switched to output, maintaining the stale output config
(low) instead of the requested config (high).
By switching to regmap_write_bits(), a write of the requested output
value can be forced, irrespective of the read state. Do this only for
aliased registers, so the more efficient regmap_update_bits() can still
be used for distinct registers.
Signed-off-by: Sander Vanheule <sander@svanheule.net>
Reviewed-by: Michael Walle <mwalle@kernel.org>
---
drivers/gpio/gpio-regmap.c | 12 +++++++++---
1 file changed, 9 insertions(+), 3 deletions(-)
diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
index ab9e4077fa60..ba3c19206ccf 100644
--- a/drivers/gpio/gpio-regmap.c
+++ b/drivers/gpio/gpio-regmap.c
@@ -93,7 +93,7 @@ static int gpio_regmap_set(struct gpio_chip *chip, unsigned int offset,
{
struct gpio_regmap *gpio = gpiochip_get_data(chip);
unsigned int base = gpio_regmap_addr(gpio->reg_set_base);
- unsigned int reg, mask;
+ unsigned int reg, mask, mask_val;
int ret;
ret = gpio->reg_mask_xlate(gpio, base, offset, ®, &mask);
@@ -101,9 +101,15 @@ static int gpio_regmap_set(struct gpio_chip *chip, unsigned int offset,
return ret;
if (val)
- ret = regmap_update_bits(gpio->regmap, reg, mask, mask);
+ mask_val = mask;
else
- ret = regmap_update_bits(gpio->regmap, reg, mask, 0);
+ mask_val = 0;
+
+ /* ignore input values which shadow the old output value */
+ if (gpio->reg_dat_base == gpio->reg_set_base)
+ ret = regmap_write_bits(gpio->regmap, reg, mask, mask_val);
+ else
+ ret = regmap_update_bits(gpio->regmap, reg, mask, mask_val);
return ret;
}
--
2.51.0
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH v6 2/8] gpio: regmap: Bypass cache for aliased inputs
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
2025-10-21 14:23 ` [PATCH v6 1/8] gpio: regmap: Force writes for aliased data regs Sander Vanheule
@ 2025-10-21 14:23 ` Sander Vanheule
2025-10-23 12:06 ` Bartosz Golaszewski
2025-10-21 14:23 ` [PATCH v6 3/8] dt-bindings: leds: Binding for RTL8231 scan matrix Sander Vanheule
` (7 subsequent siblings)
9 siblings, 1 reply; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:23 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
GPIO chips often have data input and output registers aliased to the
same offset. The output register is non-valitile and could in theory be
cached. The input register however is volatile by nature and hence
should not be cached, resulting in different requirements for reads and
writes.
The generic gpio chip implementation stores a shadow value of the pin
output data, which is updated and written to hardware on output data
changes in bgpio_set(), bgpio_set_set(). Pin input values are always
obtained by reading the aliased data register from hardware.
For gpio-regmap the situation is more complex as the output data could
be in multiple registers, but we can use the regmap cache to shadow the
output values when marking the data registers as non-volatile. By using
regmap_read_bypassed() we can still treat the input values as volatile,
irrespective of the regmap config. This ensures proper functioning of
writing the output register with regmap_write_bits(), which will then
use and update the cache only on data writes, gaining some performance
from the cached output values.
Signed-off-by: Sander Vanheule <sander@svanheule.net>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Michael Walle <mwalle@kernel.org>
--
Changes since RFC:
- Add review tags
- Slightly reworded the commit message
---
drivers/gpio/gpio-regmap.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
index ba3c19206ccf..afecacf7607f 100644
--- a/drivers/gpio/gpio-regmap.c
+++ b/drivers/gpio/gpio-regmap.c
@@ -81,7 +81,11 @@ static int gpio_regmap_get(struct gpio_chip *chip, unsigned int offset)
if (ret)
return ret;
- ret = regmap_read(gpio->regmap, reg, &val);
+ /* ensure we don't spoil any register cache with pin input values */
+ if (gpio->reg_dat_base == gpio->reg_set_base)
+ ret = regmap_read_bypassed(gpio->regmap, reg, &val);
+ else
+ ret = regmap_read(gpio->regmap, reg, &val);
if (ret)
return ret;
--
2.51.0
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH v6 3/8] dt-bindings: leds: Binding for RTL8231 scan matrix
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
2025-10-21 14:23 ` [PATCH v6 1/8] gpio: regmap: Force writes for aliased data regs Sander Vanheule
2025-10-21 14:23 ` [PATCH v6 2/8] gpio: regmap: Bypass cache for aliased inputs Sander Vanheule
@ 2025-10-21 14:23 ` Sander Vanheule
2025-10-26 21:59 ` Rob Herring
2025-10-21 14:23 ` [PATCH v6 4/8] dt-bindings: mfd: Binding for RTL8231 Sander Vanheule
` (6 subsequent siblings)
9 siblings, 1 reply; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:23 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
Add a binding description for the Realtek RTL8231's LED support, which
consists of up to 88 LEDs arranged in a number of scanning matrices.
Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
.../bindings/leds/realtek,rtl8231-leds.yaml | 167 ++++++++++++++++++
1 file changed, 167 insertions(+)
create mode 100644 Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
diff --git a/Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml b/Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
new file mode 100644
index 000000000000..54e8593f8c06
--- /dev/null
+++ b/Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
@@ -0,0 +1,167 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/leds/realtek,rtl8231-leds.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Realtek RTL8231 LED scan matrix.
+
+maintainers:
+ - Sander Vanheule <sander@svanheule.net>
+
+description: |
+ The RTL8231 has support for driving a number of LED matrices, by scanning
+ over the LEDs pins, alternatingly lighting different columns and/or rows.
+
+ This functionality is available on an RTL8231, when it is configured for use
+ as an MDIO device, or SMI device.
+
+ In single color scan mode, 88 LEDs are supported. These are grouped into
+ three output matrices:
+ - Group A of 6×6 single color LEDs. Rows and columns are driven by GPIO
+ pins 0-11.
+ L0[n] L1[n] L2[n] L0[n+6] L1[n+6] L2[n+6]
+ | | | | | |
+ P0/P6 --<--------<--------<--------<--------<--------< (3)
+ | | | | | |
+ P1/P7 --<--------<--------<--------<--------<--------< (4)
+ | | | | | |
+ P2/P8 --<--------<--------<--------<--------<--------< (5)
+ | | | | | |
+ P3/P9 --<--------<--------<--------<--------<--------< (6)
+ | | | | | |
+ P4/P10 --<--------<--------<--------<--------<--------< (7)
+ | | | | | |
+ P5/P11 --<--------<--------<--------<--------<--------< (8)
+ (0) (1) (2) (9) (10) (11)
+ - Group B of 6×6 single color LEDs. Rows and columns are driven by GPIO
+ pins 12-23.
+ L0[n] L1[n] L2[n] L0[n+6] L1[n+6] L2[n+6]
+ | | | | | |
+ P12/P18 --<--------<--------<--------<--------<--------< (15)
+ | | | | | |
+ P13/P19 --<--------<--------<--------<--------<--------< (16)
+ | | | | | |
+ P14/P20 --<--------<--------<--------<--------<--------< (17)
+ | | | | | |
+ P15/P21 --<--------<--------<--------<--------<--------< (18)
+ | | | | | |
+ P16/P22 --<--------<--------<--------<--------<--------< (19)
+ | | | | | |
+ P17/P23 --<--------<--------<--------<--------<--------< (20)
+ (12) (13) (14) (21) (22) (23)
+ - Group C of 8 pairs of anti-parallel (or bi-color) LEDs. LED selection is
+ provided by GPIO pins 24-27 and 29-32, polarity selection by GPIO 28.
+ P24 P25 ... P30 P31
+ | | | |
+ LED POL --X-------X---/\/---X-------X (28)
+ (24) (25) ... (31) (32)
+
+ In bi-color scan mode, 72 LEDs are supported. These are grouped into four
+ output matrices:
+ - Group A of 12 pairs of anti-parallel LEDs. LED selection is provided
+ by GPIO pins 0-11, polarity selection by GPIO 12.
+ - Group B of 6 pairs of anti-parallel LEDs. LED selection is provided
+ by GPIO pins 23-28, polarity selection by GPIO 21.
+ - Group C of 6 pairs of anti-parallel LEDs. LED selection is provided
+ by GPIO pins 29-34, polarity selection by GPIO 22.
+ - Group of 4×6 single color LEDs. Rows are driven by GPIO pins 15-20,
+ columns by GPIO pins 13-14 and 21-22 (shared with groups B and C).
+ L2[n] L2[n+6] L2[n+12] L2[n+18]
+ | | | |
+ +0 --<--------<---------<---------< (15)
+ | | | |
+ +1 --<--------<---------<---------< (16)
+ | | | |
+ +2 --<--------<---------<---------< (17)
+ | | | |
+ +3 --<--------<---------<---------< (18)
+ | | | |
+ +4 --<--------<---------<---------< (19)
+ | | | |
+ +6 --<--------<---------<---------< (20)
+ (13) (14) (21) (22)
+
+ This node must always be a child of a 'realtek,rtl8231' node.
+
+properties:
+ $nodename:
+ const: led-controller
+
+ compatible:
+ const: realtek,rtl8231-leds
+
+ "#address-cells":
+ const: 2
+
+ "#size-cells":
+ const: 0
+
+ realtek,led-scan-mode:
+ $ref: /schemas/types.yaml#/definitions/string
+ description: |
+ Specify the scanning mode the chip should run in. See general description
+ for how the scanning matrices are wired up.
+ enum: [single-color, bi-color]
+
+patternProperties:
+ "^led@":
+ description: |
+ LEDs are addressed by their port index and led index. Ports 0-23 always
+ support three LEDs. Additionally, but only when used in single color scan
+ mode, ports 24-31 support two LEDs.
+ type: object
+
+ properties:
+ reg:
+ items:
+ - items:
+ - description: port index
+ maximum: 31
+ - description: led index
+ maximum: 2
+
+ allOf:
+ - $ref: ../leds/common.yaml#
+
+ required:
+ - reg
+
+required:
+ - compatible
+ - "#address-cells"
+ - "#size-cells"
+ - realtek,led-scan-mode
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/leds/common.h>
+ led-controller {
+ compatible = "realtek,rtl8231-leds";
+ #address-cells = <2>;
+ #size-cells = <0>;
+
+ realtek,led-scan-mode = "single-color";
+
+ led@0,0 {
+ reg = <0 0>;
+ color = <LED_COLOR_ID_GREEN>;
+ function = LED_FUNCTION_LAN;
+ function-enumerator = <0>;
+ };
+
+ led@0,1 {
+ reg = <0 1>;
+ color = <LED_COLOR_ID_AMBER>;
+ function = LED_FUNCTION_LAN;
+ function-enumerator = <0>;
+ };
+
+ led@0,2 {
+ reg = <0 2>;
+ color = <LED_COLOR_ID_GREEN>;
+ function = LED_FUNCTION_STATUS;
+ };
+ };
--
2.51.0
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH v6 4/8] dt-bindings: mfd: Binding for RTL8231
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
` (2 preceding siblings ...)
2025-10-21 14:23 ` [PATCH v6 3/8] dt-bindings: leds: Binding for RTL8231 scan matrix Sander Vanheule
@ 2025-10-21 14:23 ` Sander Vanheule
2025-10-26 22:04 ` Rob Herring
2025-10-21 14:24 ` [PATCH v6 5/8] mfd: Add RTL8231 core device Sander Vanheule
` (5 subsequent siblings)
9 siblings, 1 reply; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:23 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
Add a binding description for the Realtek RTL8231, a GPIO and LED
expander chip commonly used in ethernet switches based on a Realtek
switch SoC. These chips can be addressed via an MDIO or SMI bus, or used
as a plain 36-bit shift register.
This binding only describes the feature set provided by the MDIO/SMI
configuration, and covers the GPIO, PWM, and pin control properties. The
LED properties are defined in a separate binding.
Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
.../bindings/mfd/realtek,rtl8231.yaml | 189 ++++++++++++++++++
1 file changed, 189 insertions(+)
create mode 100644 Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
diff --git a/Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml b/Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
new file mode 100644
index 000000000000..25135917d3f2
--- /dev/null
+++ b/Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
@@ -0,0 +1,189 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mfd/realtek,rtl8231.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Realtek RTL8231 GPIO and LED expander.
+
+maintainers:
+ - Sander Vanheule <sander@svanheule.net>
+
+description: |
+ The RTL8231 is a GPIO and LED expander chip, providing up to 37 GPIOs, up to
+ 88 LEDs, and up to one PWM output. This device is frequently used alongside
+ Realtek switch SoCs, to provide additional I/O capabilities.
+
+ To manage the RTL8231's features, its strapping pins can be used to configure
+ it in one of three modes: shift register, MDIO device, or SMI device. The
+ shift register mode does not need special support. In MDIO or SMI mode, most
+ pins can be configured as a GPIO output or LED matrix scan line/column. One
+ pin can be used as PWM output.
+
+ The GPIO, PWM, and pin control are part of the main node. LED support is
+ configured as a sub-node.
+
+properties:
+ compatible:
+ const: realtek,rtl8231
+
+ reg:
+ description: MDIO or SMI device address.
+ maxItems: 1
+
+ # GPIO support
+ gpio-controller: true
+
+ "#gpio-cells":
+ const: 2
+ description: |
+ The first cell is the pin number and the second cell is used to specify
+ the GPIO active state.
+
+ gpio-ranges:
+ description: |
+ Must reference itself, and provide a zero-based mapping for 37 pins.
+ maxItems: 1
+
+ # Pin muxing and configuration
+ drive-strength:
+ description: |
+ Common drive strength used for all GPIO output pins, must be 4mA or 8mA.
+ On reset, this value will default to 8mA.
+ enum: [4, 8]
+
+ # LED scanning matrix
+ led-controller:
+ $ref: ../leds/realtek,rtl8231-leds.yaml#
+
+ # PWM output
+ "#pwm-cells":
+ description: |
+ Twos cells with PWM index (must be 0) and PWM frequency in Hz. To use
+ the PWM output, gpio35 must be muxed to its 'pwm' function. Valid
+ frequency values for consumers are 1200, 1600, 2000, 2400, 2800, 3200,
+ 4000, and 4800.
+ const: 2
+
+patternProperties:
+ "-pins$":
+ type: object
+ $ref: ../pinctrl/pinmux-node.yaml#
+
+ properties:
+ pins:
+ items:
+ enum: [gpio0, gpio1, gpio2, gpio3, gpio4, gpio5, gpio6, gpio7,
+ gpio8, gpio9, gpio10, gpio11, gpio12, gpio13, gpio14, gpio15,
+ gpio16, gpio17, gpio18, gpio19, gpio20, gpio21, gpio22, gpio23,
+ gpio24, gpio25, gpio26, gpio27, gpio28, gpio29, gpio30, gpio31,
+ gpio32, gpio33, gpio34, gpio35, gpio36]
+ minItems: 1
+ maxItems: 37
+ function:
+ description: |
+ Select which function to use. "gpio" is supported for all pins, "led" is supported
+ for pins 0-34, "pwm" is supported for pin 35.
+ enum: [gpio, led, pwm]
+
+ required:
+ - pins
+ - function
+
+required:
+ - compatible
+ - reg
+ - gpio-controller
+ - "#gpio-cells"
+ - gpio-ranges
+
+additionalProperties: false
+
+examples:
+ - |
+ // Minimal example
+ mdio {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ expander0: expander@0 {
+ compatible = "realtek,rtl8231";
+ reg = <0>;
+
+ gpio-controller;
+ #gpio-cells = <2>;
+ gpio-ranges = <&expander0 0 0 37>;
+ };
+ };
+ - |
+ // All bells and whistles included
+ #include <dt-bindings/leds/common.h>
+ mdio {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ expander1: expander@1 {
+ compatible = "realtek,rtl8231";
+ reg = <1>;
+
+ gpio-controller;
+ #gpio-cells = <2>;
+ gpio-ranges = <&expander1 0 0 37>;
+
+ #pwm-cells = <2>;
+
+ drive-strength = <4>;
+
+ button-pins {
+ pins = "gpio36";
+ function = "gpio";
+ input-debounce = <100000>;
+ };
+
+ pwm-pins {
+ pins = "gpio35";
+ function = "pwm";
+ };
+
+ led-pins {
+ pins = "gpio0", "gpio1", "gpio3", "gpio4";
+ function = "led";
+ };
+
+ led-controller {
+ compatible = "realtek,rtl8231-leds";
+ #address-cells = <2>;
+ #size-cells = <0>;
+
+ realtek,led-scan-mode = "single-color";
+
+ led@0,0 {
+ reg = <0 0>;
+ color = <LED_COLOR_ID_GREEN>;
+ function = LED_FUNCTION_LAN;
+ function-enumerator = <0>;
+ };
+
+ led@0,1 {
+ reg = <0 1>;
+ color = <LED_COLOR_ID_AMBER>;
+ function = LED_FUNCTION_LAN;
+ function-enumerator = <0>;
+ };
+
+ led@1,0 {
+ reg = <1 0>;
+ color = <LED_COLOR_ID_GREEN>;
+ function = LED_FUNCTION_LAN;
+ function-enumerator = <1>;
+ };
+
+ led@1,1 {
+ reg = <1 1>;
+ color = <LED_COLOR_ID_AMBER>;
+ function = LED_FUNCTION_LAN;
+ function-enumerator = <1>;
+ };
+ };
+ };
+ };
--
2.51.0
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH v6 5/8] mfd: Add RTL8231 core device
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
` (3 preceding siblings ...)
2025-10-21 14:23 ` [PATCH v6 4/8] dt-bindings: mfd: Binding for RTL8231 Sander Vanheule
@ 2025-10-21 14:24 ` Sander Vanheule
2025-11-06 16:33 ` Lee Jones
2025-10-21 14:24 ` [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support Sander Vanheule
` (4 subsequent siblings)
9 siblings, 1 reply; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:24 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
The RTL8231 is implemented as an MDIO device, and provides a regmap
interface for register access by the core and child devices.
The chip can also be a device on an SMI bus, an I2C-like bus by Realtek.
Since kernel support for SMI is limited, and no real-world SMI
implementations have been encountered for this device, this is currently
unimplemented. The use of the regmap interface should make any future
support relatively straightforward.
After a soft reset, all pins are muxed to GPIO inputs before the pin
drivers are enabled. This is done to prevent accidental system resets,
when a pin is connected to the main SoC's reset line.
Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
drivers/mfd/Kconfig | 9 ++
drivers/mfd/Makefile | 1 +
drivers/mfd/rtl8231.c | 193 ++++++++++++++++++++++++++++++++++++
include/linux/mfd/rtl8231.h | 71 +++++++++++++
4 files changed, 274 insertions(+)
create mode 100644 drivers/mfd/rtl8231.c
create mode 100644 include/linux/mfd/rtl8231.h
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 6cec1858947b..e13e2df63fee 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -1301,6 +1301,15 @@ config MFD_RDC321X
southbridge which provides access to GPIOs and Watchdog using the
southbridge PCI device configuration space.
+config MFD_RTL8231
+ tristate "Realtek RTL8231 GPIO and LED expander"
+ select MFD_CORE
+ select REGMAP_MDIO
+ help
+ Support for the Realtek RTL8231 GPIO and LED expander.
+ Provides up to 37 GPIOs, 88 LEDs, and one PWM output.
+ When built as a module, this module will be named rtl8231.
+
config MFD_RT4831
tristate "Richtek RT4831 four channel WLED and Display Bias Voltage"
depends on I2C
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 865e9f12faff..ba973382a20f 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -252,6 +252,7 @@ obj-$(CONFIG_MFD_HI6421_PMIC) += hi6421-pmic-core.o
obj-$(CONFIG_MFD_HI6421_SPMI) += hi6421-spmi-pmic.o
obj-$(CONFIG_MFD_HI655X_PMIC) += hi655x-pmic.o
obj-$(CONFIG_MFD_DLN2) += dln2.o
+obj-$(CONFIG_MFD_RTL8231) += rtl8231.o
obj-$(CONFIG_MFD_RT4831) += rt4831.o
obj-$(CONFIG_MFD_RT5033) += rt5033.o
obj-$(CONFIG_MFD_RT5120) += rt5120.o
diff --git a/drivers/mfd/rtl8231.c b/drivers/mfd/rtl8231.c
new file mode 100644
index 000000000000..60d4a0feea5c
--- /dev/null
+++ b/drivers/mfd/rtl8231.c
@@ -0,0 +1,193 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/bits.h>
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/mfd/core.h>
+#include <linux/mdio.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+#include <linux/mfd/rtl8231.h>
+
+static bool rtl8231_volatile_reg(struct device *dev, unsigned int reg)
+{
+ switch (reg) {
+ /*
+ * Registers with self-clearing bits, strapping pin values.
+ * Don't mark the data registers as volatile, since we need
+ * caching for the output values.
+ */
+ case RTL8231_REG_FUNC0:
+ case RTL8231_REG_FUNC1:
+ case RTL8231_REG_PIN_HI_CFG:
+ case RTL8231_REG_LED_END:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static const struct reg_field RTL8231_FIELD_LED_START = REG_FIELD(RTL8231_REG_FUNC0, 1, 1);
+
+static const struct mfd_cell rtl8231_cells[] = {
+ {
+ .name = "rtl8231-pinctrl",
+ },
+ {
+ .name = "rtl8231-leds",
+ .of_compatible = "realtek,rtl8231-leds",
+ },
+};
+
+static int rtl8231_soft_reset(struct regmap *map)
+{
+ const unsigned int all_pins_mask = GENMASK(RTL8231_BITS_VAL - 1, 0);
+ unsigned int val;
+ int err;
+
+ /* SOFT_RESET bit self-clears when done */
+ regmap_write_bits(map, RTL8231_REG_PIN_HI_CFG,
+ RTL8231_PIN_HI_CFG_SOFT_RESET, RTL8231_PIN_HI_CFG_SOFT_RESET);
+ err = regmap_read_poll_timeout(map, RTL8231_REG_PIN_HI_CFG, val,
+ !(val & RTL8231_PIN_HI_CFG_SOFT_RESET), 50, 1000);
+ if (err)
+ return err;
+
+ regcache_mark_dirty(map);
+
+ /*
+ * Chip reset results in a pin configuration that is a mix of LED and GPIO outputs.
+ * Select GPI functionality for all pins before enabling pin outputs.
+ */
+ regmap_write(map, RTL8231_REG_PIN_MODE0, all_pins_mask);
+ regmap_write(map, RTL8231_REG_GPIO_DIR0, all_pins_mask);
+ regmap_write(map, RTL8231_REG_PIN_MODE1, all_pins_mask);
+ regmap_write(map, RTL8231_REG_GPIO_DIR1, all_pins_mask);
+ regmap_write(map, RTL8231_REG_PIN_HI_CFG,
+ RTL8231_PIN_HI_CFG_MODE_MASK | RTL8231_PIN_HI_CFG_DIR_MASK);
+
+ return 0;
+}
+
+static int rtl8231_init(struct device *dev, struct regmap *map)
+{
+ struct regmap_field *led_start;
+ unsigned int started;
+ unsigned int val;
+ int err;
+
+ err = regmap_read(map, RTL8231_REG_FUNC1, &val);
+ if (err) {
+ dev_err(dev, "failed to read READY_CODE\n");
+ return err;
+ }
+
+ val = FIELD_GET(RTL8231_FUNC1_READY_CODE_MASK, val);
+ if (val != RTL8231_FUNC1_READY_CODE_VALUE) {
+ dev_err(dev, "RTL8231 not present or ready 0x%x != 0x%x\n",
+ val, RTL8231_FUNC1_READY_CODE_VALUE);
+ return -ENODEV;
+ }
+
+ led_start = dev_get_drvdata(dev);
+ err = regmap_field_read(led_start, &started);
+ if (err)
+ return err;
+
+ if (!started) {
+ err = rtl8231_soft_reset(map);
+ if (err)
+ return err;
+ /* LED_START enables power to output pins, and starts the LED engine */
+ err = regmap_field_force_write(led_start, 1);
+ }
+
+ return err;
+}
+
+static const struct regmap_config rtl8231_mdio_regmap_config = {
+ .val_bits = RTL8231_BITS_VAL,
+ .reg_bits = RTL8231_BITS_REG,
+ .volatile_reg = rtl8231_volatile_reg,
+ .max_register = RTL8231_REG_COUNT - 1,
+ .use_single_read = true,
+ .use_single_write = true,
+ .reg_format_endian = REGMAP_ENDIAN_BIG,
+ .val_format_endian = REGMAP_ENDIAN_BIG,
+ /* Cannot use REGCACHE_FLAT because it's not smart enough about cache invalidation */
+ .cache_type = REGCACHE_MAPLE,
+};
+
+static int rtl8231_mdio_probe(struct mdio_device *mdiodev)
+{
+ struct device *dev = &mdiodev->dev;
+ struct regmap_field *led_start;
+ struct regmap *map;
+ int err;
+
+ map = devm_regmap_init_mdio(mdiodev, &rtl8231_mdio_regmap_config);
+ if (IS_ERR(map)) {
+ dev_err(dev, "failed to init regmap\n");
+ return PTR_ERR(map);
+ }
+
+ led_start = devm_regmap_field_alloc(dev, map, RTL8231_FIELD_LED_START);
+ if (IS_ERR(led_start))
+ return PTR_ERR(led_start);
+
+ dev_set_drvdata(dev, led_start);
+
+ mdiodev->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(mdiodev->reset_gpio))
+ return PTR_ERR(mdiodev->reset_gpio);
+
+ device_property_read_u32(dev, "reset-assert-delay", &mdiodev->reset_assert_delay);
+ device_property_read_u32(dev, "reset-deassert-delay", &mdiodev->reset_deassert_delay);
+
+ err = rtl8231_init(dev, map);
+ if (err)
+ return err;
+
+ return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, rtl8231_cells,
+ ARRAY_SIZE(rtl8231_cells), NULL, 0, NULL);
+}
+
+__maybe_unused static int rtl8231_suspend(struct device *dev)
+{
+ struct regmap_field *led_start = dev_get_drvdata(dev);
+
+ return regmap_field_force_write(led_start, 0);
+}
+
+__maybe_unused static int rtl8231_resume(struct device *dev)
+{
+ struct regmap_field *led_start = dev_get_drvdata(dev);
+
+ return regmap_field_force_write(led_start, 1);
+}
+
+static SIMPLE_DEV_PM_OPS(rtl8231_pm_ops, rtl8231_suspend, rtl8231_resume);
+
+static const struct of_device_id rtl8231_of_match[] = {
+ { .compatible = "realtek,rtl8231" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, rtl8231_of_match);
+
+static struct mdio_driver rtl8231_mdio_driver = {
+ .mdiodrv.driver = {
+ .name = "rtl8231-expander",
+ .of_match_table = rtl8231_of_match,
+ .pm = pm_ptr(&rtl8231_pm_ops),
+ },
+ .probe = rtl8231_mdio_probe,
+};
+mdio_module_driver(rtl8231_mdio_driver);
+
+MODULE_AUTHOR("Sander Vanheule <sander@svanheule.net>");
+MODULE_DESCRIPTION("Realtek RTL8231 GPIO and LED expander");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/mfd/rtl8231.h b/include/linux/mfd/rtl8231.h
new file mode 100644
index 000000000000..003eda3797a3
--- /dev/null
+++ b/include/linux/mfd/rtl8231.h
@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Register definitions the RTL8231 GPIO and LED expander chip
+ */
+
+#ifndef __LINUX_MFD_RTL8231_H
+#define __LINUX_MFD_RTL8231_H
+
+#include <linux/bits.h>
+
+/*
+ * Registers addresses are 5 bit, values are 16 bit
+ * Also define a duplicated range of virtual addresses, to enable
+ * different read/write behaviour on the GPIO data registers
+ */
+#define RTL8231_BITS_VAL 16
+#define RTL8231_BITS_REG 5
+
+/* Chip control */
+#define RTL8231_REG_FUNC0 0x00
+#define RTL8231_FUNC0_SCAN_MODE BIT(0)
+#define RTL8231_FUNC0_SCAN_SINGLE 0
+#define RTL8231_FUNC0_SCAN_BICOLOR BIT(0)
+
+#define RTL8231_REG_FUNC1 0x01
+#define RTL8231_FUNC1_READY_CODE_VALUE 0x37
+#define RTL8231_FUNC1_READY_CODE_MASK GENMASK(9, 4)
+#define RTL8231_FUNC1_DEBOUNCE_MASK GENMASK(15, 10)
+
+/* Pin control */
+#define RTL8231_REG_PIN_MODE0 0x02
+#define RTL8231_REG_PIN_MODE1 0x03
+
+#define RTL8231_PIN_MODE_LED 0
+#define RTL8231_PIN_MODE_GPIO 1
+
+/* Pin high config: pin and GPIO control for pins 32-26 */
+#define RTL8231_REG_PIN_HI_CFG 0x04
+#define RTL8231_PIN_HI_CFG_MODE_MASK GENMASK(4, 0)
+#define RTL8231_PIN_HI_CFG_DIR_MASK GENMASK(9, 5)
+#define RTL8231_PIN_HI_CFG_INV_MASK GENMASK(14, 10)
+#define RTL8231_PIN_HI_CFG_SOFT_RESET BIT(15)
+
+/* GPIO control registers */
+#define RTL8231_REG_GPIO_DIR0 0x05
+#define RTL8231_REG_GPIO_DIR1 0x06
+#define RTL8231_REG_GPIO_INVERT0 0x07
+#define RTL8231_REG_GPIO_INVERT1 0x08
+
+#define RTL8231_GPIO_DIR_IN 1
+#define RTL8231_GPIO_DIR_OUT 0
+
+/*
+ * GPIO data registers
+ * Only the output data can be written to these registers, and only the input
+ * data can be read.
+ */
+#define RTL8231_REG_GPIO_DATA0 0x1c
+#define RTL8231_REG_GPIO_DATA1 0x1d
+#define RTL8231_REG_GPIO_DATA2 0x1e
+#define RTL8231_PIN_HI_DATA_MASK GENMASK(4, 0)
+
+/* LED control base registers */
+#define RTL8231_REG_LED0_BASE 0x09
+#define RTL8231_REG_LED1_BASE 0x10
+#define RTL8231_REG_LED2_BASE 0x17
+#define RTL8231_REG_LED_END 0x1b
+
+#define RTL8231_REG_COUNT 0x1f
+
+#endif /* __LINUX_MFD_RTL8231_H */
--
2.51.0
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
` (4 preceding siblings ...)
2025-10-21 14:24 ` [PATCH v6 5/8] mfd: Add RTL8231 core device Sander Vanheule
@ 2025-10-21 14:24 ` Sander Vanheule
2025-10-22 1:47 ` kernel test robot
` (2 more replies)
2025-10-21 14:24 ` [PATCH v6 7/8] leds: Add support for RTL8231 LED scan matrix Sander Vanheule
` (3 subsequent siblings)
9 siblings, 3 replies; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:24 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
This driver implements the GPIO and pin muxing features provided by the
RTL8231. The device should be instantiated as an MFD child, where the
parent device has already configured the regmap used for register
access.
Debouncing is only available for the six highest GPIOs, and must be
emulated when other pins are used for (button) inputs. Although
described in the bindings, drive strength selection is currently not
implemented.
Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
drivers/pinctrl/Kconfig | 11 +
drivers/pinctrl/Makefile | 1 +
drivers/pinctrl/pinctrl-rtl8231.c | 538 ++++++++++++++++++++++++++++++
3 files changed, 550 insertions(+)
create mode 100644 drivers/pinctrl/pinctrl-rtl8231.c
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 4f8507ebbdac..75007ba7b80e 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -520,6 +520,17 @@ config PINCTRL_ROCKCHIP
help
This support pinctrl and GPIO driver for Rockchip SoCs.
+config PINCTRL_RTL8231
+ tristate "Realtek RTL8231 GPIO expander's pin controller"
+ depends on MFD_RTL8231
+ default MFD_RTL8231
+ select GPIO_REGMAP
+ select GENERIC_PINCONF
+ select GENERIC_PINMUX_FUNCTIONS
+ help
+ Support for RTL8231 expander's GPIOs and pin controller.
+ When built as a module, the module will be called pinctrl-rtl8231.
+
config PINCTRL_SCMI
tristate "Pinctrl driver using SCMI protocol interface"
depends on ARM_SCMI_PROTOCOL || COMPILE_TEST
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index e0cfb9b7c99b..ded51723d452 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_PINCTRL_PISTACHIO) += pinctrl-pistachio.o
obj-$(CONFIG_PINCTRL_RK805) += pinctrl-rk805.o
obj-$(CONFIG_PINCTRL_ROCKCHIP) += pinctrl-rockchip.o
obj-$(CONFIG_PINCTRL_RP1) += pinctrl-rp1.o
+obj-$(CONFIG_PINCTRL_RTL8231) += pinctrl-rtl8231.o
obj-$(CONFIG_PINCTRL_SCMI) += pinctrl-scmi.o
obj-$(CONFIG_PINCTRL_SINGLE) += pinctrl-single.o
obj-$(CONFIG_PINCTRL_ST) += pinctrl-st.o
diff --git a/drivers/pinctrl/pinctrl-rtl8231.c b/drivers/pinctrl/pinctrl-rtl8231.c
new file mode 100644
index 000000000000..e562259d9ffd
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-rtl8231.c
@@ -0,0 +1,538 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/bitfield.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio/regmap.h>
+#include <linux/module.h>
+#include <linux/pinctrl/pinconf.h>
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include "core.h"
+#include "pinmux.h"
+#include <linux/mfd/rtl8231.h>
+
+#define RTL8231_NUM_GPIOS 37
+#define RTL8231_DEBOUNCE_USEC 100000
+#define RTL8231_DEBOUNCE_MIN_OFFSET 31
+
+struct rtl8231_pin_ctrl {
+ struct regmap *map;
+};
+
+/*
+ * Pin controller functionality
+ */
+enum rtl8231_pin_function {
+ RTL8231_PIN_FUNCTION_GPIO = BIT(0),
+ RTL8231_PIN_FUNCTION_LED = BIT(1),
+ RTL8231_PIN_FUNCTION_PWM = BIT(2),
+};
+
+struct rtl8231_function_info {
+ enum rtl8231_pin_function flag;
+ const char *name;
+};
+
+#define RTL8231_FUNCTION(_name, _flag) \
+((struct rtl8231_function_info) { \
+ .flag = (_flag), \
+ .name = (_name), \
+ })
+
+static const struct rtl8231_function_info rtl8231_pin_functions[] = {
+ RTL8231_FUNCTION("gpio", RTL8231_PIN_FUNCTION_GPIO),
+ RTL8231_FUNCTION("led", RTL8231_PIN_FUNCTION_LED),
+ RTL8231_FUNCTION("pwm", RTL8231_PIN_FUNCTION_PWM),
+};
+
+struct rtl8231_pin_desc {
+ enum rtl8231_pin_function functions:8;
+ u8 reg;
+ u8 offset;
+ u8 gpio_function_value;
+};
+
+#define RTL8231_PIN_DESC(_num, _func, _reg, _fld, _val) \
+ [(_num)] = ((struct rtl8231_pin_desc) { \
+ .functions = RTL8231_PIN_FUNCTION_GPIO | (_func), \
+ .reg = (_reg), \
+ .offset = (_fld), \
+ .gpio_function_value = (_val), \
+ })
+#define RTL8231_GPIO_PIN_DESC(_num, _reg, _fld) \
+ RTL8231_PIN_DESC(_num, 0, _reg, _fld, RTL8231_PIN_MODE_GPIO)
+#define RTL8231_LED_PIN_DESC(_num, _reg, _fld) \
+ RTL8231_PIN_DESC(_num, RTL8231_PIN_FUNCTION_LED, _reg, _fld, RTL8231_PIN_MODE_GPIO)
+#define RTL8231_PWM_PIN_DESC(_num, _reg, _fld) \
+ RTL8231_PIN_DESC(_num, RTL8231_PIN_FUNCTION_PWM, _reg, _fld, 0)
+
+/*
+ * All pins have a GPIO/LED mux bit, but the bits for pins 35/36 are read-only. Use this bit
+ * for the GPIO-only pin instead of a placeholder, so the rest of the logic can stay generic.
+ */
+static const struct rtl8231_pin_desc rtl8231_pin_data[RTL8231_NUM_GPIOS] = {
+ RTL8231_LED_PIN_DESC(0, RTL8231_REG_PIN_MODE0, 0),
+ RTL8231_LED_PIN_DESC(1, RTL8231_REG_PIN_MODE0, 1),
+ RTL8231_LED_PIN_DESC(2, RTL8231_REG_PIN_MODE0, 2),
+ RTL8231_LED_PIN_DESC(3, RTL8231_REG_PIN_MODE0, 3),
+ RTL8231_LED_PIN_DESC(4, RTL8231_REG_PIN_MODE0, 4),
+ RTL8231_LED_PIN_DESC(5, RTL8231_REG_PIN_MODE0, 5),
+ RTL8231_LED_PIN_DESC(6, RTL8231_REG_PIN_MODE0, 6),
+ RTL8231_LED_PIN_DESC(7, RTL8231_REG_PIN_MODE0, 7),
+ RTL8231_LED_PIN_DESC(8, RTL8231_REG_PIN_MODE0, 8),
+ RTL8231_LED_PIN_DESC(9, RTL8231_REG_PIN_MODE0, 9),
+ RTL8231_LED_PIN_DESC(10, RTL8231_REG_PIN_MODE0, 10),
+ RTL8231_LED_PIN_DESC(11, RTL8231_REG_PIN_MODE0, 11),
+ RTL8231_LED_PIN_DESC(12, RTL8231_REG_PIN_MODE0, 12),
+ RTL8231_LED_PIN_DESC(13, RTL8231_REG_PIN_MODE0, 13),
+ RTL8231_LED_PIN_DESC(14, RTL8231_REG_PIN_MODE0, 14),
+ RTL8231_LED_PIN_DESC(15, RTL8231_REG_PIN_MODE0, 15),
+ RTL8231_LED_PIN_DESC(16, RTL8231_REG_PIN_MODE1, 0),
+ RTL8231_LED_PIN_DESC(17, RTL8231_REG_PIN_MODE1, 1),
+ RTL8231_LED_PIN_DESC(18, RTL8231_REG_PIN_MODE1, 2),
+ RTL8231_LED_PIN_DESC(19, RTL8231_REG_PIN_MODE1, 3),
+ RTL8231_LED_PIN_DESC(20, RTL8231_REG_PIN_MODE1, 4),
+ RTL8231_LED_PIN_DESC(21, RTL8231_REG_PIN_MODE1, 5),
+ RTL8231_LED_PIN_DESC(22, RTL8231_REG_PIN_MODE1, 6),
+ RTL8231_LED_PIN_DESC(23, RTL8231_REG_PIN_MODE1, 7),
+ RTL8231_LED_PIN_DESC(24, RTL8231_REG_PIN_MODE1, 8),
+ RTL8231_LED_PIN_DESC(25, RTL8231_REG_PIN_MODE1, 9),
+ RTL8231_LED_PIN_DESC(26, RTL8231_REG_PIN_MODE1, 10),
+ RTL8231_LED_PIN_DESC(27, RTL8231_REG_PIN_MODE1, 11),
+ RTL8231_LED_PIN_DESC(28, RTL8231_REG_PIN_MODE1, 12),
+ RTL8231_LED_PIN_DESC(29, RTL8231_REG_PIN_MODE1, 13),
+ RTL8231_LED_PIN_DESC(30, RTL8231_REG_PIN_MODE1, 14),
+ RTL8231_LED_PIN_DESC(31, RTL8231_REG_PIN_MODE1, 15),
+ RTL8231_LED_PIN_DESC(32, RTL8231_REG_PIN_HI_CFG, 0),
+ RTL8231_LED_PIN_DESC(33, RTL8231_REG_PIN_HI_CFG, 1),
+ RTL8231_LED_PIN_DESC(34, RTL8231_REG_PIN_HI_CFG, 2),
+ RTL8231_PWM_PIN_DESC(35, RTL8231_REG_FUNC1, 3),
+ RTL8231_GPIO_PIN_DESC(36, RTL8231_REG_PIN_HI_CFG, 4),
+};
+static const unsigned int PWM_PIN = 35;
+
+#define RTL8231_PIN(_num) \
+ ((struct pinctrl_pin_desc) { \
+ .number = (_num), \
+ .name = "gpio" #_num, \
+ .drv_data = (void *) &rtl8231_pin_data[(_num)] \
+ })
+
+static const struct pinctrl_pin_desc rtl8231_pins[RTL8231_NUM_GPIOS] = {
+ RTL8231_PIN(0),
+ RTL8231_PIN(1),
+ RTL8231_PIN(2),
+ RTL8231_PIN(3),
+ RTL8231_PIN(4),
+ RTL8231_PIN(5),
+ RTL8231_PIN(6),
+ RTL8231_PIN(7),
+ RTL8231_PIN(8),
+ RTL8231_PIN(9),
+ RTL8231_PIN(10),
+ RTL8231_PIN(11),
+ RTL8231_PIN(12),
+ RTL8231_PIN(13),
+ RTL8231_PIN(14),
+ RTL8231_PIN(15),
+ RTL8231_PIN(16),
+ RTL8231_PIN(17),
+ RTL8231_PIN(18),
+ RTL8231_PIN(19),
+ RTL8231_PIN(20),
+ RTL8231_PIN(21),
+ RTL8231_PIN(22),
+ RTL8231_PIN(23),
+ RTL8231_PIN(24),
+ RTL8231_PIN(25),
+ RTL8231_PIN(26),
+ RTL8231_PIN(27),
+ RTL8231_PIN(28),
+ RTL8231_PIN(29),
+ RTL8231_PIN(30),
+ RTL8231_PIN(31),
+ RTL8231_PIN(32),
+ RTL8231_PIN(33),
+ RTL8231_PIN(34),
+ RTL8231_PIN(35),
+ RTL8231_PIN(36),
+};
+
+static int rtl8231_get_groups_count(struct pinctrl_dev *pctldev)
+{
+ return ARRAY_SIZE(rtl8231_pins);
+}
+
+static const char *rtl8231_get_group_name(struct pinctrl_dev *pctldev, unsigned int selector)
+{
+ return rtl8231_pins[selector].name;
+}
+
+static int rtl8231_get_group_pins(struct pinctrl_dev *pctldev, unsigned int selector,
+ const unsigned int **pins, unsigned int *num_pins)
+{
+ if (selector >= ARRAY_SIZE(rtl8231_pins))
+ return -EINVAL;
+
+ *pins = &rtl8231_pins[selector].number;
+ *num_pins = 1;
+
+ return 0;
+}
+
+static const struct pinctrl_ops rtl8231_pinctrl_ops = {
+ .get_groups_count = rtl8231_get_groups_count,
+ .get_group_name = rtl8231_get_group_name,
+ .get_group_pins = rtl8231_get_group_pins,
+ .dt_node_to_map = pinconf_generic_dt_node_to_map_all,
+ .dt_free_map = pinconf_generic_dt_free_map,
+};
+
+static int rtl8231_set_mux(struct pinctrl_dev *pctldev, unsigned int func_selector,
+ unsigned int group_selector)
+{
+ const struct function_desc *func = pinmux_generic_get_function(pctldev, func_selector);
+ const struct rtl8231_pin_desc *desc = rtl8231_pins[group_selector].drv_data;
+ const struct rtl8231_pin_ctrl *ctrl = pinctrl_dev_get_drvdata(pctldev);
+ unsigned int func_flag = (uintptr_t) func->data;
+ unsigned int function_mask;
+ unsigned int gpio_function;
+
+ if (!(desc->functions & func_flag))
+ return -EINVAL;
+
+ function_mask = BIT(desc->offset);
+ gpio_function = desc->gpio_function_value << desc->offset;
+
+ if (func_flag == RTL8231_PIN_FUNCTION_GPIO)
+ return regmap_update_bits(ctrl->map, desc->reg, function_mask, gpio_function);
+ else
+ return regmap_update_bits(ctrl->map, desc->reg, function_mask, ~gpio_function);
+}
+
+static int rtl8231_gpio_request_enable(struct pinctrl_dev *pctldev,
+ struct pinctrl_gpio_range *range, unsigned int offset)
+{
+ const struct rtl8231_pin_desc *desc = rtl8231_pins[offset].drv_data;
+ const struct rtl8231_pin_ctrl *ctrl = pinctrl_dev_get_drvdata(pctldev);
+ unsigned int function_mask;
+ unsigned int gpio_function;
+
+ function_mask = BIT(desc->offset);
+ gpio_function = desc->gpio_function_value << desc->offset;
+
+ return regmap_update_bits(ctrl->map, desc->reg, function_mask, gpio_function);
+}
+
+static const struct pinmux_ops rtl8231_pinmux_ops = {
+ .get_functions_count = pinmux_generic_get_function_count,
+ .get_function_name = pinmux_generic_get_function_name,
+ .get_function_groups = pinmux_generic_get_function_groups,
+ .function_is_gpio = pinmux_generic_function_is_gpio,
+ .set_mux = rtl8231_set_mux,
+ .gpio_request_enable = rtl8231_gpio_request_enable,
+ .strict = true,
+};
+
+static int rtl8231_pin_config_get(struct pinctrl_dev *pctldev, unsigned int offset,
+ unsigned long *config)
+{
+ const struct rtl8231_pin_ctrl *ctrl = pinctrl_dev_get_drvdata(pctldev);
+ unsigned int param = pinconf_to_config_param(*config);
+ unsigned int arg;
+ int err;
+ int v;
+
+ switch (param) {
+ case PIN_CONFIG_INPUT_DEBOUNCE:
+ if (offset < RTL8231_DEBOUNCE_MIN_OFFSET)
+ return -EINVAL;
+
+ err = regmap_read(ctrl->map, RTL8231_REG_FUNC1, &v);
+ if (err)
+ return err;
+
+ v = FIELD_GET(RTL8231_FUNC1_DEBOUNCE_MASK, v);
+ if (v & BIT(offset - RTL8231_DEBOUNCE_MIN_OFFSET))
+ arg = RTL8231_DEBOUNCE_USEC;
+ else
+ arg = 0;
+ break;
+ default:
+ return -ENOTSUPP;
+ }
+
+ *config = pinconf_to_config_packed(param, arg);
+
+ return 0;
+}
+
+static int rtl8231_pin_config_set(struct pinctrl_dev *pctldev, unsigned int offset,
+ unsigned long *configs, unsigned int num_configs)
+{
+ const struct rtl8231_pin_ctrl *ctrl = pinctrl_dev_get_drvdata(pctldev);
+ unsigned int param, arg;
+ unsigned int pin_mask;
+ int err;
+ int i;
+
+ for (i = 0; i < num_configs; i++) {
+ param = pinconf_to_config_param(configs[i]);
+ arg = pinconf_to_config_argument(configs[i]);
+
+ switch (param) {
+ case PIN_CONFIG_INPUT_DEBOUNCE:
+ if (offset < RTL8231_DEBOUNCE_MIN_OFFSET)
+ return -EINVAL;
+
+ pin_mask = FIELD_PREP(RTL8231_FUNC1_DEBOUNCE_MASK,
+ BIT(offset - RTL8231_DEBOUNCE_MIN_OFFSET));
+
+ switch (arg) {
+ case 0:
+ err = regmap_update_bits(ctrl->map, RTL8231_REG_FUNC1,
+ pin_mask, 0);
+ break;
+ case RTL8231_DEBOUNCE_USEC:
+ err = regmap_update_bits(ctrl->map, RTL8231_REG_FUNC1,
+ pin_mask, pin_mask);
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ break;
+ default:
+ return -ENOTSUPP;
+ }
+ }
+
+ return err;
+}
+
+static const struct pinconf_ops rtl8231_pinconf_ops = {
+ .is_generic = true,
+ .pin_config_get = rtl8231_pin_config_get,
+ .pin_config_set = rtl8231_pin_config_set,
+};
+
+static int rtl8231_pinctrl_init_functions(struct pinctrl_dev *pctl,
+ const struct pinctrl_desc *pctl_desc)
+{
+ struct pinfunction func;
+ const char **groups;
+ unsigned int f_idx;
+ unsigned int flag;
+ const char *name;
+ unsigned int pin;
+ int num_groups;
+ int err;
+
+ for (f_idx = 0; f_idx < ARRAY_SIZE(rtl8231_pin_functions); f_idx++) {
+ name = rtl8231_pin_functions[f_idx].name;
+ flag = rtl8231_pin_functions[f_idx].flag;
+
+ for (pin = 0, num_groups = 0; pin < pctl_desc->npins; pin++)
+ if (rtl8231_pin_data[pin].functions & flag)
+ num_groups++;
+
+ groups = devm_kcalloc(pctl->dev, num_groups, sizeof(*groups), GFP_KERNEL);
+ if (!groups)
+ return -ENOMEM;
+
+ for (pin = 0, num_groups = 0; pin < pctl_desc->npins; pin++)
+ if (rtl8231_pin_data[pin].functions & flag)
+ groups[num_groups++] = rtl8231_pins[pin].name;
+
+ func = PINCTRL_PINFUNCTION(name, groups, num_groups);
+ if (flag == RTL8231_PIN_FUNCTION_GPIO)
+ func.flags |= PINFUNCTION_FLAG_GPIO;
+
+ err = pinmux_generic_add_pinfunction(pctl, &func, (void *) flag);
+ if (err < 0)
+ return err;
+ }
+
+ return 0;
+}
+
+struct pin_field_info {
+ const struct reg_field gpio_dir;
+ const struct reg_field mode;
+};
+
+static const struct pin_field_info pin_fields[] = {
+ {
+ .gpio_dir = REG_FIELD(RTL8231_REG_GPIO_DIR0, 0, 15),
+ .mode = REG_FIELD(RTL8231_REG_PIN_MODE0, 0, 15),
+ },
+ {
+ .gpio_dir = REG_FIELD(RTL8231_REG_GPIO_DIR1, 0, 15),
+ .mode = REG_FIELD(RTL8231_REG_PIN_MODE1, 0, 15),
+ },
+ {
+ .gpio_dir = REG_FIELD(RTL8231_REG_PIN_HI_CFG, 5, 9),
+ .mode = REG_FIELD(RTL8231_REG_PIN_HI_CFG, 0, 4),
+ },
+};
+
+static int rtl8231_configure_safe(struct device *dev, struct regmap *map)
+{
+ struct regmap_field *field_mode;
+ struct regmap_field *field_dir;
+ unsigned int is_output;
+ unsigned int is_gpio;
+ unsigned int mode;
+ unsigned int dir;
+ int err;
+
+ for (unsigned int i = 0; i < ARRAY_SIZE(pin_fields); i++) {
+ field_dir = devm_regmap_field_alloc(dev, map, pin_fields[i].gpio_dir);
+ if (IS_ERR(field_dir))
+ return PTR_ERR(field_dir);
+
+ field_mode = devm_regmap_field_alloc(dev, map, pin_fields[i].mode);
+ if (IS_ERR(field_mode))
+ return PTR_ERR(field_mode);
+
+ err = regmap_field_read(field_dir, &dir);
+ if (err)
+ return err;
+
+ err = regmap_field_read(field_mode, &mode);
+ if (err)
+ return err;
+
+ /*
+ * Set every pin that is configured as gpio-output but muxed for the alternative
+ * (LED) function to gpio-in. That way the pin will be high impedance when it is
+ * muxed to GPIO, preventing unwanted glitches.
+ */
+ is_gpio = mode;
+ is_output = ~dir;
+
+ /* Enable field for PWM (on GPIO35) is in another register */
+ if (pin_fields[i].mode.reg == RTL8231_REG_PIN_HI_CFG) {
+ err = regmap_test_bits(map, rtl8231_pin_data[PWM_PIN].reg,
+ BIT(rtl8231_pin_data[PWM_PIN].offset));
+ if (err < 0)
+ return err;
+
+ if (err)
+ is_gpio &= ~BIT(PWM_PIN % RTL8231_BITS_VAL);
+ }
+
+ /* The pin muxes are left as-is, so there are no signal changes. */
+ regmap_field_write(field_dir, dir | (~is_gpio & is_output));
+
+ devm_regmap_field_free(dev, field_dir);
+ devm_regmap_field_free(dev, field_mode);
+ }
+
+ return 0;
+}
+
+static const struct pinctrl_desc rtl8231_pctl_desc = {
+ .name = "rtl8231-pinctrl",
+ .owner = THIS_MODULE,
+ .confops = &rtl8231_pinconf_ops,
+ .pctlops = &rtl8231_pinctrl_ops,
+ .pmxops = &rtl8231_pinmux_ops,
+ .npins = ARRAY_SIZE(rtl8231_pins),
+ .pins = rtl8231_pins,
+};
+
+static int rtl8231_pinctrl_init(struct device *dev, struct rtl8231_pin_ctrl *ctrl)
+{
+ struct pinctrl_dev *pctldev;
+ int err;
+
+ err = devm_pinctrl_register_and_init(dev->parent, &rtl8231_pctl_desc, ctrl, &pctldev);
+ if (err) {
+ dev_err(dev, "failed to register pin controller\n");
+ return err;
+ }
+
+ err = rtl8231_pinctrl_init_functions(pctldev, &rtl8231_pctl_desc);
+ if (err)
+ return err;
+
+ err = pinctrl_enable(pctldev);
+ if (err)
+ dev_err(dev, "failed to enable pin controller\n");
+
+ return err;
+}
+
+/*
+ * GPIO controller functionality
+ */
+static int rtl8231_gpio_reg_mask_xlate(struct gpio_regmap *gpio, unsigned int base,
+ unsigned int offset, unsigned int *reg, unsigned int *mask)
+{
+ unsigned int pin_mask = BIT(offset % RTL8231_BITS_VAL);
+
+ if (base == RTL8231_REG_GPIO_DATA0 || offset < 32) {
+ *reg = base + offset / RTL8231_BITS_VAL;
+ *mask = pin_mask;
+ } else if (base == RTL8231_REG_GPIO_DIR0) {
+ *reg = RTL8231_REG_PIN_HI_CFG;
+ *mask = FIELD_PREP(RTL8231_PIN_HI_CFG_DIR_MASK, pin_mask);
+ } else {
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int rtl8231_pinctrl_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct rtl8231_pin_ctrl *ctrl;
+ struct gpio_regmap_config gpio_cfg = {};
+ int err;
+
+ ctrl = devm_kzalloc(dev, sizeof(*ctrl), GFP_KERNEL);
+ if (!ctrl)
+ return -ENOMEM;
+
+ ctrl->map = dev_get_regmap(dev->parent, NULL);
+ if (!ctrl->map)
+ return -ENODEV;
+
+ err = rtl8231_configure_safe(dev, ctrl->map);
+ if (err)
+ return err;
+
+ err = rtl8231_pinctrl_init(dev, ctrl);
+ if (err)
+ return err;
+
+ gpio_cfg.regmap = ctrl->map;
+ gpio_cfg.parent = dev->parent;
+ gpio_cfg.ngpio = RTL8231_NUM_GPIOS;
+ gpio_cfg.ngpio_per_reg = RTL8231_BITS_VAL;
+
+ gpio_cfg.reg_dat_base = GPIO_REGMAP_ADDR(RTL8231_REG_GPIO_DATA0);
+ gpio_cfg.reg_set_base = GPIO_REGMAP_ADDR(RTL8231_REG_GPIO_DATA0);
+ gpio_cfg.reg_dir_in_base = GPIO_REGMAP_ADDR(RTL8231_REG_GPIO_DIR0);
+
+ gpio_cfg.reg_mask_xlate = rtl8231_gpio_reg_mask_xlate;
+
+ return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &gpio_cfg));
+}
+
+static struct platform_driver rtl8231_pinctrl_driver = {
+ .driver = {
+ .name = "rtl8231-pinctrl",
+ },
+ .probe = rtl8231_pinctrl_probe,
+};
+module_platform_driver(rtl8231_pinctrl_driver);
+
+MODULE_AUTHOR("Sander Vanheule <sander@svanheule.net>");
+MODULE_DESCRIPTION("Realtek RTL8231 pin control and GPIO support");
+MODULE_LICENSE("GPL");
--
2.51.0
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH v6 7/8] leds: Add support for RTL8231 LED scan matrix
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
` (5 preceding siblings ...)
2025-10-21 14:24 ` [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support Sander Vanheule
@ 2025-10-21 14:24 ` Sander Vanheule
2025-10-21 14:24 ` [PATCH v6 8/8] MAINTAINERS: Add RTL8231 MFD driver Sander Vanheule
` (2 subsequent siblings)
9 siblings, 0 replies; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:24 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
Both single and bi-color scanning modes are supported. The driver will
verify that the addresses are valid for the current mode, before
registering the LEDs. LEDs can be turned on, off, or toggled at one of
six predefined rates from 40ms to 1280ms.
Implements a platform device for use as a child device with RTL8231 MFD,
and uses the parent regmap to access the required registers.
Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
drivers/leds/Kconfig | 10 ++
drivers/leds/Makefile | 1 +
drivers/leds/leds-rtl8231.c | 285 ++++++++++++++++++++++++++++++++++++
3 files changed, 296 insertions(+)
create mode 100644 drivers/leds/leds-rtl8231.c
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 06e6291be11b..bb4429bcd7a2 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -666,6 +666,16 @@ config LEDS_REGULATOR
help
This option enables support for regulator driven LEDs.
+config LEDS_RTL8231
+ tristate "RTL8231 LED matrix support"
+ depends on LEDS_CLASS
+ depends on MFD_RTL8231
+ default MFD_RTL8231
+ help
+ This option enables support for using the LED scanning matrix output
+ of the RTL8231 GPIO and LED expander chip.
+ When built as a module, this module will be named leds-rtl8231.
+
config LEDS_BD2606MVV
tristate "LED driver for BD2606MVV"
depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index 9a0333ec1a86..27c32204aebc 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -84,6 +84,7 @@ obj-$(CONFIG_LEDS_POWERNV) += leds-powernv.o
obj-$(CONFIG_LEDS_PWM) += leds-pwm.o
obj-$(CONFIG_LEDS_QNAP_MCU) += leds-qnap-mcu.o
obj-$(CONFIG_LEDS_REGULATOR) += leds-regulator.o
+obj-$(CONFIG_LEDS_RTL8231) += leds-rtl8231.o
obj-$(CONFIG_LEDS_SC27XX_BLTC) += leds-sc27xx-bltc.o
obj-$(CONFIG_LEDS_ST1202) += leds-st1202.o
obj-$(CONFIG_LEDS_SUN50I_A100) += leds-sun50i-a100.o
diff --git a/drivers/leds/leds-rtl8231.c b/drivers/leds/leds-rtl8231.c
new file mode 100644
index 000000000000..8ff20cc7ea98
--- /dev/null
+++ b/drivers/leds/leds-rtl8231.c
@@ -0,0 +1,285 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/device.h>
+#include <linux/leds.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+
+#include <linux/mfd/rtl8231.h>
+
+/**
+ * struct led_toggle_rate - description of an LED blinking mode
+ * @interval_ms: LED toggle rate in milliseconds
+ * @mode: Register field value used to activate this mode
+ *
+ * For LED hardware accelerated blinking, with equal on and off delay.
+ * Both delays are given by @interval, so the interval at which the LED blinks
+ * (i.e. turn on and off once) is double this value.
+ */
+struct led_toggle_rate {
+ u16 interval_ms;
+ u8 mode;
+};
+
+/**
+ * struct led_modes - description of all LED modes
+ * @toggle_rates: Array of led_toggle_rate values, sorted by ascending interval
+ * @num_toggle_rates: Number of elements in @led_toggle_rate
+ * @off: Register field value to turn LED off
+ * @on: Register field value to turn LED on
+ */
+struct led_modes {
+ const struct led_toggle_rate *toggle_rates;
+ unsigned int num_toggle_rates;
+ u8 off;
+ u8 on;
+};
+
+struct rtl8231_led {
+ struct led_classdev led;
+ const struct led_modes *modes;
+ struct regmap_field *reg_field;
+};
+#define to_rtl8231_led(_cdev) container_of(_cdev, struct rtl8231_led, led)
+
+#define RTL8231_NUM_LEDS 3
+#define RTL8231_LED_PER_REG 5
+#define RTL8231_BITS_PER_LED 3
+
+static const unsigned int rtl8231_led_port_counts_single[RTL8231_NUM_LEDS] = {32, 32, 24};
+static const unsigned int rtl8231_led_port_counts_bicolor[RTL8231_NUM_LEDS] = {24, 24, 24};
+
+static const unsigned int rtl8231_led_base[RTL8231_NUM_LEDS] = {
+ RTL8231_REG_LED0_BASE,
+ RTL8231_REG_LED1_BASE,
+ RTL8231_REG_LED2_BASE,
+};
+
+#define RTL8231_DEFAULT_TOGGLE_INTERVAL_MS 500
+
+static const struct led_toggle_rate rtl8231_toggle_rates[] = {
+ { 40, 1},
+ { 80, 2},
+ { 160, 3},
+ { 320, 4},
+ { 640, 5},
+ {1280, 6},
+};
+
+static const struct led_modes rtl8231_led_modes = {
+ .off = 0,
+ .on = 7,
+ .num_toggle_rates = ARRAY_SIZE(rtl8231_toggle_rates),
+ .toggle_rates = rtl8231_toggle_rates,
+};
+
+static void rtl8231_led_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ struct rtl8231_led *pled = to_rtl8231_led(led_cdev);
+
+ if (brightness)
+ regmap_field_write(pled->reg_field, pled->modes->on);
+ else
+ regmap_field_write(pled->reg_field, pled->modes->off);
+}
+
+static enum led_brightness rtl8231_led_brightness_get(struct led_classdev *led_cdev)
+{
+ struct rtl8231_led *pled = to_rtl8231_led(led_cdev);
+ u32 current_mode = pled->modes->off;
+
+ regmap_field_read(pled->reg_field, ¤t_mode);
+
+ if (current_mode == pled->modes->off)
+ return LED_OFF;
+ else
+ return LED_ON;
+}
+
+static unsigned int rtl8231_led_current_interval(struct rtl8231_led *pled)
+{
+ unsigned int mode;
+ unsigned int i;
+
+ if (regmap_field_read(pled->reg_field, &mode))
+ return 0;
+
+ for (i = 0; i < pled->modes->num_toggle_rates; i++)
+ if (mode == pled->modes->toggle_rates[i].mode)
+ return pled->modes->toggle_rates[i].interval_ms;
+
+ return 0;
+}
+
+static int rtl8231_led_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on,
+ unsigned long *delay_off)
+{
+ struct rtl8231_led *pled = to_rtl8231_led(led_cdev);
+ const struct led_toggle_rate *rates = pled->modes->toggle_rates;
+ unsigned int num_rates = pled->modes->num_toggle_rates;
+ unsigned int interval_ms;
+ unsigned int i;
+ int err;
+
+ if (*delay_on == 0 && *delay_off == 0) {
+ interval_ms = RTL8231_DEFAULT_TOGGLE_INTERVAL_MS;
+ } else {
+ /*
+ * If the current mode is blinking, choose the delay that (likely) changed.
+ * Otherwise, choose the interval that would have the same total delay.
+ */
+ interval_ms = rtl8231_led_current_interval(pled);
+ if (interval_ms > 0 && interval_ms == *delay_off)
+ interval_ms = *delay_on;
+ else if (interval_ms > 0 && interval_ms == *delay_on)
+ interval_ms = *delay_off;
+ else
+ interval_ms = (*delay_on + *delay_off) / 2;
+ }
+
+ /* Find clamped toggle interval */
+ for (i = 0; i < (num_rates - 1); i++)
+ if (interval_ms > rates[i].interval_ms)
+ break;
+
+ interval_ms = rates[i].interval_ms;
+
+ err = regmap_field_write(pled->reg_field, rates[i].mode);
+ if (err)
+ return err;
+
+ *delay_on = interval_ms;
+ *delay_off = interval_ms;
+
+ return 0;
+}
+
+static int rtl8231_led_read_address(struct fwnode_handle *fwnode, unsigned int *addr_port,
+ unsigned int *addr_led)
+{
+ u32 addr[2];
+ int err;
+
+ err = fwnode_property_count_u32(fwnode, "reg");
+ if (err < 0)
+ return err;
+ if (err != ARRAY_SIZE(addr))
+ return -EINVAL;
+
+ err = fwnode_property_read_u32_array(fwnode, "reg", addr, ARRAY_SIZE(addr));
+ if (err)
+ return err;
+
+ *addr_port = addr[0];
+ *addr_led = addr[1];
+
+ return 0;
+}
+
+static struct regmap_field *rtl8231_led_get_field(struct device *dev, struct regmap *map,
+ unsigned int port_index, unsigned int led_index)
+{
+ unsigned int offset = port_index / RTL8231_LED_PER_REG;
+ unsigned int shift = (port_index % RTL8231_LED_PER_REG) * RTL8231_BITS_PER_LED;
+ const struct reg_field field = REG_FIELD(rtl8231_led_base[led_index] + offset, shift,
+ shift + RTL8231_BITS_PER_LED - 1);
+
+ return devm_regmap_field_alloc(dev, map, field);
+}
+
+static int rtl8231_led_probe_single(struct device *dev, struct regmap *map,
+ const unsigned int *port_counts, struct fwnode_handle *fwnode)
+{
+ struct led_init_data init_data = {};
+ struct rtl8231_led *pled;
+ unsigned int port_index;
+ unsigned int led_index;
+ int err;
+
+ pled = devm_kzalloc(dev, sizeof(*pled), GFP_KERNEL);
+ if (!pled)
+ return -ENOMEM;
+
+ err = rtl8231_led_read_address(fwnode, &port_index, &led_index);
+ if (err) {
+ dev_err(dev, "LED address invalid");
+ return err;
+ }
+
+ if (led_index >= RTL8231_NUM_LEDS || port_index >= port_counts[led_index]) {
+ dev_err(dev, "LED address (%d.%d) invalid", port_index, led_index);
+ return -EINVAL;
+ }
+
+ pled->reg_field = rtl8231_led_get_field(dev, map, port_index, led_index);
+ if (IS_ERR(pled->reg_field))
+ return PTR_ERR(pled->reg_field);
+
+ pled->modes = &rtl8231_led_modes;
+
+ pled->led.max_brightness = 1;
+ pled->led.brightness_get = rtl8231_led_brightness_get;
+ pled->led.brightness_set = rtl8231_led_brightness_set;
+ pled->led.blink_set = rtl8231_led_blink_set;
+
+ init_data.fwnode = fwnode;
+
+ return devm_led_classdev_register_ext(dev, &pled->led, &init_data);
+}
+
+static int rtl8231_led_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ const unsigned int *port_counts;
+ struct fwnode_handle *child;
+ struct regmap *map;
+ int err;
+
+ map = dev_get_regmap(dev->parent, NULL);
+ if (!map)
+ return -ENODEV;
+
+ if (device_property_match_string(dev, "realtek,led-scan-mode", "single-color") >= 0) {
+ port_counts = rtl8231_led_port_counts_single;
+ regmap_update_bits(map, RTL8231_REG_FUNC0,
+ RTL8231_FUNC0_SCAN_MODE, RTL8231_FUNC0_SCAN_SINGLE);
+ } else if (device_property_match_string(dev, "realtek,led-scan-mode", "bi-color") >= 0) {
+ port_counts = rtl8231_led_port_counts_bicolor;
+ regmap_update_bits(map, RTL8231_REG_FUNC0,
+ RTL8231_FUNC0_SCAN_MODE, RTL8231_FUNC0_SCAN_BICOLOR);
+ } else {
+ dev_err(dev, "scan mode missing or invalid");
+ return -EINVAL;
+ }
+
+ fwnode_for_each_available_child_node(dev->fwnode, child) {
+ err = rtl8231_led_probe_single(dev, map, port_counts, child);
+ if (err)
+ dev_warn(dev, "failed to register LED %pfwP", child);
+ }
+
+ return 0;
+}
+
+static const struct of_device_id of_rtl8231_led_match[] = {
+ { .compatible = "realtek,rtl8231-leds" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, of_rtl8231_led_match);
+
+static struct platform_driver rtl8231_led_driver = {
+ .driver = {
+ .name = "rtl8231-leds",
+ .of_match_table = of_rtl8231_led_match,
+ },
+ .probe = rtl8231_led_probe,
+};
+module_platform_driver(rtl8231_led_driver);
+
+MODULE_AUTHOR("Sander Vanheule <sander@svanheule.net>");
+MODULE_DESCRIPTION("Realtek RTL8231 LED support");
+MODULE_LICENSE("GPL");
--
2.51.0
^ permalink raw reply related [flat|nested] 22+ messages in thread
* [PATCH v6 8/8] MAINTAINERS: Add RTL8231 MFD driver
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
` (6 preceding siblings ...)
2025-10-21 14:24 ` [PATCH v6 7/8] leds: Add support for RTL8231 LED scan matrix Sander Vanheule
@ 2025-10-21 14:24 ` Sander Vanheule
2025-10-23 9:05 ` [PATCH v6 0/8] RTL8231 GPIO expander support Bartosz Golaszewski
2025-10-23 12:05 ` (subset) " Bartosz Golaszewski
9 siblings, 0 replies; 22+ messages in thread
From: Sander Vanheule @ 2025-10-21 14:24 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree
Cc: linux-kernel, Sander Vanheule
Add the files associated with the RTL8231 support, and list Sander
Vanheule (myself) as maintainer.
Signed-off-by: Sander Vanheule <sander@svanheule.net>
---
MAINTAINERS | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 46126ce2f968..a83c57091a9d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21630,6 +21630,16 @@ S: Maintained
F: Documentation/devicetree/bindings/watchdog/realtek,otto-wdt.yaml
F: drivers/watchdog/realtek_otto_wdt.c
+REALTEK RTL8231 MFD DRIVER
+M: Sander Vanheule <sander@svanheule.net>
+S: Maintained
+F: Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
+F: Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
+F: drivers/leds/leds-rtl8231.c
+F: drivers/mfd/rtl8231.c
+F: drivers/pinctrl/pinctrl-rtl8231.c
+F: include/linux/mfd/rtl8231.h
+
REALTEK RTL83xx SMI DSA ROUTER CHIPS
M: Linus Walleij <linus.walleij@linaro.org>
M: Alvin Šipraga <alsi@bang-olufsen.dk>
--
2.51.0
^ permalink raw reply related [flat|nested] 22+ messages in thread
* Re: [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support
2025-10-21 14:24 ` [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support Sander Vanheule
@ 2025-10-22 1:47 ` kernel test robot
2025-10-22 5:01 ` kernel test robot
2025-10-22 7:42 ` Linus Walleij
2 siblings, 0 replies; 22+ messages in thread
From: kernel test robot @ 2025-10-22 1:47 UTC (permalink / raw)
To: Sander Vanheule, Michael Walle, Linus Walleij,
Bartosz Golaszewski, linux-gpio, Lee Jones, Pavel Machek,
Rob Herring, Krzysztof Kozlowski, Conor Dooley, linux-leds,
devicetree
Cc: llvm, oe-kbuild-all, linux-kernel, Sander Vanheule
Hi Sander,
kernel test robot noticed the following build warnings:
[auto build test WARNING on lee-mfd/for-mfd-next]
[also build test WARNING on lee-mfd/for-mfd-fixes linusw-pinctrl/devel linusw-pinctrl/for-next lee-leds/for-leds-next linus/master v6.18-rc2 next-20251021]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Sander-Vanheule/gpio-regmap-Force-writes-for-aliased-data-regs/20251021-222846
base: https://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git for-mfd-next
patch link: https://lore.kernel.org/r/20251021142407.307753-7-sander%40svanheule.net
patch subject: [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support
config: x86_64-randconfig-004-20251022 (https://download.01.org/0day-ci/archive/20251022/202510220909.HJVE90Ky-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251022/202510220909.HJVE90Ky-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510220909.HJVE90Ky-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/pinctrl/pinctrl-rtl8231.c:354:53: warning: cast to 'void *' from smaller integer type 'unsigned int' [-Wint-to-void-pointer-cast]
354 | err = pinmux_generic_add_pinfunction(pctl, &func, (void *) flag);
| ^~~~~~~~~~~~~
1 warning generated.
vim +354 drivers/pinctrl/pinctrl-rtl8231.c
321
322 static int rtl8231_pinctrl_init_functions(struct pinctrl_dev *pctl,
323 const struct pinctrl_desc *pctl_desc)
324 {
325 struct pinfunction func;
326 const char **groups;
327 unsigned int f_idx;
328 unsigned int flag;
329 const char *name;
330 unsigned int pin;
331 int num_groups;
332 int err;
333
334 for (f_idx = 0; f_idx < ARRAY_SIZE(rtl8231_pin_functions); f_idx++) {
335 name = rtl8231_pin_functions[f_idx].name;
336 flag = rtl8231_pin_functions[f_idx].flag;
337
338 for (pin = 0, num_groups = 0; pin < pctl_desc->npins; pin++)
339 if (rtl8231_pin_data[pin].functions & flag)
340 num_groups++;
341
342 groups = devm_kcalloc(pctl->dev, num_groups, sizeof(*groups), GFP_KERNEL);
343 if (!groups)
344 return -ENOMEM;
345
346 for (pin = 0, num_groups = 0; pin < pctl_desc->npins; pin++)
347 if (rtl8231_pin_data[pin].functions & flag)
348 groups[num_groups++] = rtl8231_pins[pin].name;
349
350 func = PINCTRL_PINFUNCTION(name, groups, num_groups);
351 if (flag == RTL8231_PIN_FUNCTION_GPIO)
352 func.flags |= PINFUNCTION_FLAG_GPIO;
353
> 354 err = pinmux_generic_add_pinfunction(pctl, &func, (void *) flag);
355 if (err < 0)
356 return err;
357 }
358
359 return 0;
360 }
361
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support
2025-10-21 14:24 ` [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support Sander Vanheule
2025-10-22 1:47 ` kernel test robot
@ 2025-10-22 5:01 ` kernel test robot
2025-10-22 7:42 ` Linus Walleij
2 siblings, 0 replies; 22+ messages in thread
From: kernel test robot @ 2025-10-22 5:01 UTC (permalink / raw)
To: Sander Vanheule, Michael Walle, Linus Walleij,
Bartosz Golaszewski, linux-gpio, Lee Jones, Pavel Machek,
Rob Herring, Krzysztof Kozlowski, Conor Dooley, linux-leds,
devicetree
Cc: oe-kbuild-all, linux-kernel, Sander Vanheule
Hi Sander,
kernel test robot noticed the following build warnings:
[auto build test WARNING on lee-mfd/for-mfd-next]
[also build test WARNING on lee-mfd/for-mfd-fixes linusw-pinctrl/devel linusw-pinctrl/for-next lee-leds/for-leds-next linus/master v6.18-rc2 next-20251021]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Sander-Vanheule/gpio-regmap-Force-writes-for-aliased-data-regs/20251021-222846
base: https://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd.git for-mfd-next
patch link: https://lore.kernel.org/r/20251021142407.307753-7-sander%40svanheule.net
patch subject: [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support
config: alpha-allyesconfig (https://download.01.org/0day-ci/archive/20251022/202510221215.irTQwvxA-lkp@intel.com/config)
compiler: alpha-linux-gcc (GCC) 15.1.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251022/202510221215.irTQwvxA-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510221215.irTQwvxA-lkp@intel.com/
All warnings (new ones prefixed by >>):
drivers/pinctrl/pinctrl-rtl8231.c: In function 'rtl8231_pinctrl_init_functions':
>> drivers/pinctrl/pinctrl-rtl8231.c:354:67: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
354 | err = pinmux_generic_add_pinfunction(pctl, &func, (void *) flag);
| ^
vim +354 drivers/pinctrl/pinctrl-rtl8231.c
321
322 static int rtl8231_pinctrl_init_functions(struct pinctrl_dev *pctl,
323 const struct pinctrl_desc *pctl_desc)
324 {
325 struct pinfunction func;
326 const char **groups;
327 unsigned int f_idx;
328 unsigned int flag;
329 const char *name;
330 unsigned int pin;
331 int num_groups;
332 int err;
333
334 for (f_idx = 0; f_idx < ARRAY_SIZE(rtl8231_pin_functions); f_idx++) {
335 name = rtl8231_pin_functions[f_idx].name;
336 flag = rtl8231_pin_functions[f_idx].flag;
337
338 for (pin = 0, num_groups = 0; pin < pctl_desc->npins; pin++)
339 if (rtl8231_pin_data[pin].functions & flag)
340 num_groups++;
341
342 groups = devm_kcalloc(pctl->dev, num_groups, sizeof(*groups), GFP_KERNEL);
343 if (!groups)
344 return -ENOMEM;
345
346 for (pin = 0, num_groups = 0; pin < pctl_desc->npins; pin++)
347 if (rtl8231_pin_data[pin].functions & flag)
348 groups[num_groups++] = rtl8231_pins[pin].name;
349
350 func = PINCTRL_PINFUNCTION(name, groups, num_groups);
351 if (flag == RTL8231_PIN_FUNCTION_GPIO)
352 func.flags |= PINFUNCTION_FLAG_GPIO;
353
> 354 err = pinmux_generic_add_pinfunction(pctl, &func, (void *) flag);
355 if (err < 0)
356 return err;
357 }
358
359 return 0;
360 }
361
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support
2025-10-21 14:24 ` [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support Sander Vanheule
2025-10-22 1:47 ` kernel test robot
2025-10-22 5:01 ` kernel test robot
@ 2025-10-22 7:42 ` Linus Walleij
2025-10-22 7:52 ` Linus Walleij
2025-10-22 8:24 ` Sander Vanheule
2 siblings, 2 replies; 22+ messages in thread
From: Linus Walleij @ 2025-10-22 7:42 UTC (permalink / raw)
To: Sander Vanheule
Cc: Michael Walle, Bartosz Golaszewski, linux-gpio, Lee Jones,
Pavel Machek, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
linux-leds, devicetree, linux-kernel
Hi Sander,
thanks for your patch!
Overall this driver looks very good and well designed, using the
right abstractions and everything.
The build bots are complaining but I think you will have fixed that
in no time.
Just one minor comment:
On Tue, Oct 21, 2025 at 4:24 PM Sander Vanheule <sander@svanheule.net> wrote:
> This driver implements the GPIO and pin muxing features provided by the
> RTL8231. The device should be instantiated as an MFD child, where the
> parent device has already configured the regmap used for register
> access.
This is Realtek, right?
> drivers/pinctrl/pinctrl-rtl8231.c | 538 ++++++++++++++++++++++++++++++
Should we put the driver in
drivers/pinctrl/realtek/*?
Yours,
Linus Walleij
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support
2025-10-22 7:42 ` Linus Walleij
@ 2025-10-22 7:52 ` Linus Walleij
2025-10-22 8:24 ` Sander Vanheule
1 sibling, 0 replies; 22+ messages in thread
From: Linus Walleij @ 2025-10-22 7:52 UTC (permalink / raw)
To: Sander Vanheule
Cc: Michael Walle, Bartosz Golaszewski, linux-gpio, Lee Jones,
Pavel Machek, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
linux-leds, devicetree, linux-kernel
Replying to self:
On Wed, Oct 22, 2025 at 9:42 AM Linus Walleij <linus.walleij@linaro.org> wrote:
> > drivers/pinctrl/pinctrl-rtl8231.c | 538 ++++++++++++++++++++++++++++++
>
> Should we put the driver in
> drivers/pinctrl/realtek/*?
This is because these are SoC drivers and this is an MFD
expander, right. Keep it where it is!
Sorry for the noise.
This driver is finished.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Yours,
Linus Walleij
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support
2025-10-22 7:42 ` Linus Walleij
2025-10-22 7:52 ` Linus Walleij
@ 2025-10-22 8:24 ` Sander Vanheule
1 sibling, 0 replies; 22+ messages in thread
From: Sander Vanheule @ 2025-10-22 8:24 UTC (permalink / raw)
To: Linus Walleij
Cc: Michael Walle, Bartosz Golaszewski, linux-gpio, Lee Jones,
Pavel Machek, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
linux-leds, devicetree, linux-kernel
Hi Linus,
On Wed, 2025-10-22 at 09:42 +0200, Linus Walleij wrote:
> Hi Sander,
>
> thanks for your patch!
>
> Overall this driver looks very good and well designed, using the
> right abstractions and everything.
Thanks!
> The build bots are complaining but I think you will have fixed that
> in no time.
Indeed, I reproduced it on a UM build and resolved it by changing the underlying type for
enum rtl8231_pin_function to uintptr_t.
Additionally, this showed that I was missing CONFIG_GPIOLIB, so PINCTRL_RTL8231 now
selects that as well.
>
> Just one minor comment:
>
> On Tue, Oct 21, 2025 at 4:24 PM Sander Vanheule <sander@svanheule.net> wrote:
>
> > This driver implements the GPIO and pin muxing features provided by the
> > RTL8231. The device should be instantiated as an MFD child, where the
> > parent device has already configured the regmap used for register
> > access.
>
> This is Realtek, right?
>
> > drivers/pinctrl/pinctrl-rtl8231.c | 538 ++++++++++++++++++++++++++++++
>
> Should we put the driver in
> drivers/pinctrl/realtek/*?
Like you noticed, this is for an external chip, so I also decided to not move it to that
directory.
Best,
Sander
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 0/8] RTL8231 GPIO expander support
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
` (7 preceding siblings ...)
2025-10-21 14:24 ` [PATCH v6 8/8] MAINTAINERS: Add RTL8231 MFD driver Sander Vanheule
@ 2025-10-23 9:05 ` Bartosz Golaszewski
2025-10-23 9:09 ` Sander Vanheule
2025-10-23 12:05 ` (subset) " Bartosz Golaszewski
9 siblings, 1 reply; 22+ messages in thread
From: Bartosz Golaszewski @ 2025-10-23 9:05 UTC (permalink / raw)
To: Sander Vanheule
Cc: Michael Walle, Linus Walleij, linux-gpio, Lee Jones, Pavel Machek,
Rob Herring, Krzysztof Kozlowski, Conor Dooley, linux-leds,
devicetree, linux-kernel
On Tue, Oct 21, 2025 at 4:24 PM Sander Vanheule <sander@svanheule.net> wrote:
>
> The RTL8231 GPIO and LED expander can be configured for use as an MDIO
> or SMI bus device. Currently only the MDIO mode is supported, although
> SMI mode support should be fairly straightforward, once an SMI bus
> driver is available.
>
> Provided features by the RTL8231:
> - Up to 37 GPIOs
> - Configurable drive strength: 8mA or 4mA (currently unsupported)
> - Input debouncing on GPIOs 31-36
> - Up to 88 LEDs in multiple scan matrix groups
> - On, off, or one of six toggling intervals
> - "single-color mode": 2×36 single color LEDs + 8 bi-color LEDs
> - "bi-color mode": (12 + 2×6) bi-color LEDs + 24 single color LEDs
> - Up to one PWM output (currently unsupported)
> - Fixed duty cycle, 8 selectable frequencies (1.2kHz - 4.8kHz)
>
> The patches have been in use downstream by OpenWrt for some months. As
> the original patches are already a few years old, I would like to request
> all patches to be reviewed again (and I've dropped all provided tags and
> changelogs).
> ---
> RFC for gpio-regmap changes:
> Link: https://lore.kernel.org/lkml/20251020115636.55417-1-sander@svanheule.net/
>
> Patch series v5 (June 2021):
> Link: https://lore.kernel.org/lkml/cover.1623532208.git.sander@svanheule.net/
>
> Sander Vanheule (8):
> gpio: regmap: Force writes for aliased data regs
> gpio: regmap: Bypass cache for aliased inputs
If I'm not mistaken, nothing depends on these two at build-time, so I
can just take them through the GPIO tree for v6.19?
Bart
> dt-bindings: leds: Binding for RTL8231 scan matrix
> dt-bindings: mfd: Binding for RTL8231
> mfd: Add RTL8231 core device
> pinctrl: Add RTL8231 pin control and GPIO support
> leds: Add support for RTL8231 LED scan matrix
> MAINTAINERS: Add RTL8231 MFD driver
>
> .../bindings/leds/realtek,rtl8231-leds.yaml | 167 ++++++
> .../bindings/mfd/realtek,rtl8231.yaml | 189 ++++++
> MAINTAINERS | 10 +
> drivers/gpio/gpio-regmap.c | 18 +-
> drivers/leds/Kconfig | 10 +
> drivers/leds/Makefile | 1 +
> drivers/leds/leds-rtl8231.c | 285 ++++++++++
> drivers/mfd/Kconfig | 9 +
> drivers/mfd/Makefile | 1 +
> drivers/mfd/rtl8231.c | 193 +++++++
> drivers/pinctrl/Kconfig | 11 +
> drivers/pinctrl/Makefile | 1 +
> drivers/pinctrl/pinctrl-rtl8231.c | 538 ++++++++++++++++++
> include/linux/mfd/rtl8231.h | 71 +++
> 14 files changed, 1500 insertions(+), 4 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
> create mode 100644 Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
> create mode 100644 drivers/leds/leds-rtl8231.c
> create mode 100644 drivers/mfd/rtl8231.c
> create mode 100644 drivers/pinctrl/pinctrl-rtl8231.c
> create mode 100644 include/linux/mfd/rtl8231.h
>
> --
> 2.51.0
>
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 0/8] RTL8231 GPIO expander support
2025-10-23 9:05 ` [PATCH v6 0/8] RTL8231 GPIO expander support Bartosz Golaszewski
@ 2025-10-23 9:09 ` Sander Vanheule
0 siblings, 0 replies; 22+ messages in thread
From: Sander Vanheule @ 2025-10-23 9:09 UTC (permalink / raw)
To: Bartosz Golaszewski
Cc: Michael Walle, Linus Walleij, linux-gpio, Lee Jones, Pavel Machek,
Rob Herring, Krzysztof Kozlowski, Conor Dooley, linux-leds,
devicetree, linux-kernel
Hi,
On Thu, 2025-10-23 at 11:05 +0200, Bartosz Golaszewski wrote:
> On Tue, Oct 21, 2025 at 4:24 PM Sander Vanheule <sander@svanheule.net> wrote:
> >
> > The RTL8231 GPIO and LED expander can be configured for use as an MDIO
> > or SMI bus device. Currently only the MDIO mode is supported, although
> > SMI mode support should be fairly straightforward, once an SMI bus
> > driver is available.
> >
> > Provided features by the RTL8231:
> > - Up to 37 GPIOs
> > - Configurable drive strength: 8mA or 4mA (currently unsupported)
> > - Input debouncing on GPIOs 31-36
> > - Up to 88 LEDs in multiple scan matrix groups
> > - On, off, or one of six toggling intervals
> > - "single-color mode": 2×36 single color LEDs + 8 bi-color LEDs
> > - "bi-color mode": (12 + 2×6) bi-color LEDs + 24 single color LEDs
> > - Up to one PWM output (currently unsupported)
> > - Fixed duty cycle, 8 selectable frequencies (1.2kHz - 4.8kHz)
> >
> > The patches have been in use downstream by OpenWrt for some months. As
> > the original patches are already a few years old, I would like to request
> > all patches to be reviewed again (and I've dropped all provided tags and
> > changelogs).
> > ---
> > RFC for gpio-regmap changes:
> > Link:
> > https://lore.kernel.org/lkml/20251020115636.55417-1-sander@svanheule.net/
> >
> > Patch series v5 (June 2021):
> > Link:
> > https://lore.kernel.org/lkml/cover.1623532208.git.sander@svanheule.net/
> >
> > Sander Vanheule (8):
> > gpio: regmap: Force writes for aliased data regs
> > gpio: regmap: Bypass cache for aliased inputs
>
> If I'm not mistaken, nothing depends on these two at build-time, so I
> can just take them through the GPIO tree for v6.19?
That's okay for me.
Best,
Sander
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: (subset) [PATCH v6 0/8] RTL8231 GPIO expander support
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
` (8 preceding siblings ...)
2025-10-23 9:05 ` [PATCH v6 0/8] RTL8231 GPIO expander support Bartosz Golaszewski
@ 2025-10-23 12:05 ` Bartosz Golaszewski
9 siblings, 0 replies; 22+ messages in thread
From: Bartosz Golaszewski @ 2025-10-23 12:05 UTC (permalink / raw)
To: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, linux-leds, devicetree, Sander Vanheule
Cc: Bartosz Golaszewski, linux-kernel
From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
On Tue, 21 Oct 2025 16:23:55 +0200, Sander Vanheule wrote:
> The RTL8231 GPIO and LED expander can be configured for use as an MDIO
> or SMI bus device. Currently only the MDIO mode is supported, although
> SMI mode support should be fairly straightforward, once an SMI bus
> driver is available.
>
> Provided features by the RTL8231:
> - Up to 37 GPIOs
> - Configurable drive strength: 8mA or 4mA (currently unsupported)
> - Input debouncing on GPIOs 31-36
> - Up to 88 LEDs in multiple scan matrix groups
> - On, off, or one of six toggling intervals
> - "single-color mode": 2×36 single color LEDs + 8 bi-color LEDs
> - "bi-color mode": (12 + 2×6) bi-color LEDs + 24 single color LEDs
> - Up to one PWM output (currently unsupported)
> - Fixed duty cycle, 8 selectable frequencies (1.2kHz - 4.8kHz)
>
> [...]
Applied, thanks!
[1/8] gpio: regmap: Force writes for aliased data regs
https://git.kernel.org/brgl/linux/c/ed2bd02d24947e36c9438bee1449d9bf87671b16
[2/8] gpio: regmap: Bypass cache for aliased inputs
https://git.kernel.org/brgl/linux/c/3233741c0be59dd224e797deb2dd1621695ac95c
Best regards,
--
Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 2/8] gpio: regmap: Bypass cache for aliased inputs
2025-10-21 14:23 ` [PATCH v6 2/8] gpio: regmap: Bypass cache for aliased inputs Sander Vanheule
@ 2025-10-23 12:06 ` Bartosz Golaszewski
0 siblings, 0 replies; 22+ messages in thread
From: Bartosz Golaszewski @ 2025-10-23 12:06 UTC (permalink / raw)
To: Sander Vanheule
Cc: Michael Walle, Linus Walleij, linux-gpio, Lee Jones, Pavel Machek,
Rob Herring, Krzysztof Kozlowski, Conor Dooley, linux-leds,
devicetree, linux-kernel
On Tue, Oct 21, 2025 at 4:24 PM Sander Vanheule <sander@svanheule.net> wrote:
>
> GPIO chips often have data input and output registers aliased to the
> same offset. The output register is non-valitile and could in theory be
> cached. The input register however is volatile by nature and hence
> should not be cached, resulting in different requirements for reads and
> writes.
>
> The generic gpio chip implementation stores a shadow value of the pin
> output data, which is updated and written to hardware on output data
> changes in bgpio_set(), bgpio_set_set(). Pin input values are always
> obtained by reading the aliased data register from hardware.
>
> For gpio-regmap the situation is more complex as the output data could
> be in multiple registers, but we can use the regmap cache to shadow the
> output values when marking the data registers as non-volatile. By using
> regmap_read_bypassed() we can still treat the input values as volatile,
> irrespective of the regmap config. This ensures proper functioning of
> writing the output register with regmap_write_bits(), which will then
> use and update the cache only on data writes, gaining some performance
> from the cached output values.
>
> Signed-off-by: Sander Vanheule <sander@svanheule.net>
> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
> Reviewed-by: Michael Walle <mwalle@kernel.org>
> --
> Changes since RFC:
> - Add review tags
> - Slightly reworded the commit message
Nit: changelog should not be part of the commit message, I dropped it.
Bart
> ---
> drivers/gpio/gpio-regmap.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
> index ba3c19206ccf..afecacf7607f 100644
> --- a/drivers/gpio/gpio-regmap.c
> +++ b/drivers/gpio/gpio-regmap.c
> @@ -81,7 +81,11 @@ static int gpio_regmap_get(struct gpio_chip *chip, unsigned int offset)
> if (ret)
> return ret;
>
> - ret = regmap_read(gpio->regmap, reg, &val);
> + /* ensure we don't spoil any register cache with pin input values */
> + if (gpio->reg_dat_base == gpio->reg_set_base)
> + ret = regmap_read_bypassed(gpio->regmap, reg, &val);
> + else
> + ret = regmap_read(gpio->regmap, reg, &val);
> if (ret)
> return ret;
>
> --
> 2.51.0
>
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 3/8] dt-bindings: leds: Binding for RTL8231 scan matrix
2025-10-21 14:23 ` [PATCH v6 3/8] dt-bindings: leds: Binding for RTL8231 scan matrix Sander Vanheule
@ 2025-10-26 21:59 ` Rob Herring
2025-10-27 17:12 ` Sander Vanheule
0 siblings, 1 reply; 22+ messages in thread
From: Rob Herring @ 2025-10-26 21:59 UTC (permalink / raw)
To: Sander Vanheule
Cc: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Krzysztof Kozlowski, Conor Dooley,
linux-leds, devicetree, linux-kernel
On Tue, Oct 21, 2025 at 04:23:58PM +0200, Sander Vanheule wrote:
> Add a binding description for the Realtek RTL8231's LED support, which
> consists of up to 88 LEDs arranged in a number of scanning matrices.
>
> Signed-off-by: Sander Vanheule <sander@svanheule.net>
> ---
> .../bindings/leds/realtek,rtl8231-leds.yaml | 167 ++++++++++++++++++
> 1 file changed, 167 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
>
> diff --git a/Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml b/Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
> new file mode 100644
> index 000000000000..54e8593f8c06
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/leds/realtek,rtl8231-leds.yaml
> @@ -0,0 +1,167 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/leds/realtek,rtl8231-leds.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Realtek RTL8231 LED scan matrix.
> +
> +maintainers:
> + - Sander Vanheule <sander@svanheule.net>
> +
> +description: |
> + The RTL8231 has support for driving a number of LED matrices, by scanning
> + over the LEDs pins, alternatingly lighting different columns and/or rows.
> +
> + This functionality is available on an RTL8231, when it is configured for use
> + as an MDIO device, or SMI device.
> +
> + In single color scan mode, 88 LEDs are supported. These are grouped into
> + three output matrices:
> + - Group A of 6×6 single color LEDs. Rows and columns are driven by GPIO
> + pins 0-11.
> + L0[n] L1[n] L2[n] L0[n+6] L1[n+6] L2[n+6]
> + | | | | | |
> + P0/P6 --<--------<--------<--------<--------<--------< (3)
> + | | | | | |
> + P1/P7 --<--------<--------<--------<--------<--------< (4)
> + | | | | | |
> + P2/P8 --<--------<--------<--------<--------<--------< (5)
> + | | | | | |
> + P3/P9 --<--------<--------<--------<--------<--------< (6)
> + | | | | | |
> + P4/P10 --<--------<--------<--------<--------<--------< (7)
> + | | | | | |
> + P5/P11 --<--------<--------<--------<--------<--------< (8)
> + (0) (1) (2) (9) (10) (11)
> + - Group B of 6×6 single color LEDs. Rows and columns are driven by GPIO
> + pins 12-23.
> + L0[n] L1[n] L2[n] L0[n+6] L1[n+6] L2[n+6]
> + | | | | | |
> + P12/P18 --<--------<--------<--------<--------<--------< (15)
> + | | | | | |
> + P13/P19 --<--------<--------<--------<--------<--------< (16)
> + | | | | | |
> + P14/P20 --<--------<--------<--------<--------<--------< (17)
> + | | | | | |
> + P15/P21 --<--------<--------<--------<--------<--------< (18)
> + | | | | | |
> + P16/P22 --<--------<--------<--------<--------<--------< (19)
> + | | | | | |
> + P17/P23 --<--------<--------<--------<--------<--------< (20)
> + (12) (13) (14) (21) (22) (23)
> + - Group C of 8 pairs of anti-parallel (or bi-color) LEDs. LED selection is
> + provided by GPIO pins 24-27 and 29-32, polarity selection by GPIO 28.
> + P24 P25 ... P30 P31
> + | | | |
> + LED POL --X-------X---/\/---X-------X (28)
> + (24) (25) ... (31) (32)
> +
> + In bi-color scan mode, 72 LEDs are supported. These are grouped into four
> + output matrices:
> + - Group A of 12 pairs of anti-parallel LEDs. LED selection is provided
> + by GPIO pins 0-11, polarity selection by GPIO 12.
> + - Group B of 6 pairs of anti-parallel LEDs. LED selection is provided
> + by GPIO pins 23-28, polarity selection by GPIO 21.
> + - Group C of 6 pairs of anti-parallel LEDs. LED selection is provided
> + by GPIO pins 29-34, polarity selection by GPIO 22.
> + - Group of 4×6 single color LEDs. Rows are driven by GPIO pins 15-20,
> + columns by GPIO pins 13-14 and 21-22 (shared with groups B and C).
> + L2[n] L2[n+6] L2[n+12] L2[n+18]
> + | | | |
> + +0 --<--------<---------<---------< (15)
> + | | | |
> + +1 --<--------<---------<---------< (16)
> + | | | |
> + +2 --<--------<---------<---------< (17)
> + | | | |
> + +3 --<--------<---------<---------< (18)
> + | | | |
> + +4 --<--------<---------<---------< (19)
> + | | | |
> + +6 --<--------<---------<---------< (20)
> + (13) (14) (21) (22)
> +
> + This node must always be a child of a 'realtek,rtl8231' node.
> +
> +properties:
> + $nodename:
> + const: led-controller
> +
> + compatible:
> + const: realtek,rtl8231-leds
> +
> + "#address-cells":
> + const: 2
> +
> + "#size-cells":
> + const: 0
> +
> + realtek,led-scan-mode:
> + $ref: /schemas/types.yaml#/definitions/string
> + description: |
You don't need '|' if there is no formatting to preserve.
> + Specify the scanning mode the chip should run in. See general description
> + for how the scanning matrices are wired up.
> + enum: [single-color, bi-color]
Wouldn't 'single' and 'bi' be sufficient?
> +
> +patternProperties:
> + "^led@":
You need to define the unit-address format:
"^led@([1-2]?[0-9]|3[0-1]),[0-2]$"
> + description: |
> + LEDs are addressed by their port index and led index. Ports 0-23 always
> + support three LEDs. Additionally, but only when used in single color scan
> + mode, ports 24-31 support two LEDs.
> + type: object
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 4/8] dt-bindings: mfd: Binding for RTL8231
2025-10-21 14:23 ` [PATCH v6 4/8] dt-bindings: mfd: Binding for RTL8231 Sander Vanheule
@ 2025-10-26 22:04 ` Rob Herring
0 siblings, 0 replies; 22+ messages in thread
From: Rob Herring @ 2025-10-26 22:04 UTC (permalink / raw)
To: Sander Vanheule
Cc: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Krzysztof Kozlowski, Conor Dooley,
linux-leds, devicetree, linux-kernel
On Tue, Oct 21, 2025 at 04:23:59PM +0200, Sander Vanheule wrote:
> Add a binding description for the Realtek RTL8231, a GPIO and LED
> expander chip commonly used in ethernet switches based on a Realtek
> switch SoC. These chips can be addressed via an MDIO or SMI bus, or used
> as a plain 36-bit shift register.
>
> This binding only describes the feature set provided by the MDIO/SMI
> configuration, and covers the GPIO, PWM, and pin control properties. The
> LED properties are defined in a separate binding.
>
> Signed-off-by: Sander Vanheule <sander@svanheule.net>
> ---
> .../bindings/mfd/realtek,rtl8231.yaml | 189 ++++++++++++++++++
> 1 file changed, 189 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
>
> diff --git a/Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml b/Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
> new file mode 100644
> index 000000000000..25135917d3f2
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mfd/realtek,rtl8231.yaml
> @@ -0,0 +1,189 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mfd/realtek,rtl8231.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Realtek RTL8231 GPIO and LED expander.
> +
> +maintainers:
> + - Sander Vanheule <sander@svanheule.net>
> +
> +description: |
> + The RTL8231 is a GPIO and LED expander chip, providing up to 37 GPIOs, up to
> + 88 LEDs, and up to one PWM output. This device is frequently used alongside
> + Realtek switch SoCs, to provide additional I/O capabilities.
> +
> + To manage the RTL8231's features, its strapping pins can be used to configure
> + it in one of three modes: shift register, MDIO device, or SMI device. The
> + shift register mode does not need special support. In MDIO or SMI mode, most
> + pins can be configured as a GPIO output or LED matrix scan line/column. One
> + pin can be used as PWM output.
> +
> + The GPIO, PWM, and pin control are part of the main node. LED support is
> + configured as a sub-node.
> +
> +properties:
> + compatible:
> + const: realtek,rtl8231
> +
> + reg:
> + description: MDIO or SMI device address.
> + maxItems: 1
> +
> + # GPIO support
> + gpio-controller: true
> +
> + "#gpio-cells":
> + const: 2
> + description: |
Drop '|' here and elsewhere with no formatting.
> + The first cell is the pin number and the second cell is used to specify
> + the GPIO active state.
> +
> + gpio-ranges:
> + description: |
> + Must reference itself, and provide a zero-based mapping for 37 pins.
> + maxItems: 1
> +
> + # Pin muxing and configuration
> + drive-strength:
> + description: |
> + Common drive strength used for all GPIO output pins, must be 4mA or 8mA.
> + On reset, this value will default to 8mA.
> + enum: [4, 8]
> +
> + # LED scanning matrix
> + led-controller:
> + $ref: ../leds/realtek,rtl8231-leds.yaml#
> +
> + # PWM output
> + "#pwm-cells":
> + description: |
> + Twos cells with PWM index (must be 0) and PWM frequency in Hz. To use
> + the PWM output, gpio35 must be muxed to its 'pwm' function. Valid
> + frequency values for consumers are 1200, 1600, 2000, 2400, 2800, 3200,
> + 4000, and 4800.
> + const: 2
> +
> +patternProperties:
> + "-pins$":
> + type: object
> + $ref: ../pinctrl/pinmux-node.yaml#
> +
> + properties:
> + pins:
> + items:
> + enum: [gpio0, gpio1, gpio2, gpio3, gpio4, gpio5, gpio6, gpio7,
> + gpio8, gpio9, gpio10, gpio11, gpio12, gpio13, gpio14, gpio15,
> + gpio16, gpio17, gpio18, gpio19, gpio20, gpio21, gpio22, gpio23,
> + gpio24, gpio25, gpio26, gpio27, gpio28, gpio29, gpio30, gpio31,
> + gpio32, gpio33, gpio34, gpio35, gpio36]
> + minItems: 1
> + maxItems: 37
blank line
Other than those nits, looks good.
Rob
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 3/8] dt-bindings: leds: Binding for RTL8231 scan matrix
2025-10-26 21:59 ` Rob Herring
@ 2025-10-27 17:12 ` Sander Vanheule
0 siblings, 0 replies; 22+ messages in thread
From: Sander Vanheule @ 2025-10-27 17:12 UTC (permalink / raw)
To: Rob Herring
Cc: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Lee Jones, Pavel Machek, Krzysztof Kozlowski, Conor Dooley,
linux-leds, devicetree, linux-kernel
Hi Rob,
On Sun, 2025-10-26 at 16:59 -0500, Rob Herring wrote:
> On Tue, Oct 21, 2025 at 04:23:58PM +0200, Sander Vanheule wrote:
> > + realtek,led-scan-mode:
> > + $ref: /schemas/types.yaml#/definitions/string
> > + description: |
>
> You don't need '|' if there is no formatting to preserve.
Will drop it.
> > + Specify the scanning mode the chip should run in. See general
> > description
> > + for how the scanning matrices are wired up.
> > + enum: [single-color, bi-color]
>
> Wouldn't 'single' and 'bi' be sufficient?
I used these values to align with the datasheet:
En_bicolor
1'b0: Uses single-color LED when in Scan LED mode
1'b1: Uses bi-color LED when in Scan LED mode
If you would like a single word, I would prefer [single, dual] and mention the
single-color/bi-color mapping in the description.
>
> > +
> > +patternProperties:
> > + "^led@":
>
> You need to define the unit-address format:
>
> "^led@([1-2]?[0-9]|3[0-1]),[0-2]$"
Hadn't considered that yet. I'll update this too.
Best,
Sander
^ permalink raw reply [flat|nested] 22+ messages in thread
* Re: [PATCH v6 5/8] mfd: Add RTL8231 core device
2025-10-21 14:24 ` [PATCH v6 5/8] mfd: Add RTL8231 core device Sander Vanheule
@ 2025-11-06 16:33 ` Lee Jones
0 siblings, 0 replies; 22+ messages in thread
From: Lee Jones @ 2025-11-06 16:33 UTC (permalink / raw)
To: Sander Vanheule
Cc: Michael Walle, Linus Walleij, Bartosz Golaszewski, linux-gpio,
Pavel Machek, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
linux-leds, devicetree, linux-kernel
On Tue, 21 Oct 2025, Sander Vanheule wrote:
> The RTL8231 is implemented as an MDIO device, and provides a regmap
> interface for register access by the core and child devices.
>
> The chip can also be a device on an SMI bus, an I2C-like bus by Realtek.
> Since kernel support for SMI is limited, and no real-world SMI
> implementations have been encountered for this device, this is currently
> unimplemented. The use of the regmap interface should make any future
> support relatively straightforward.
>
> After a soft reset, all pins are muxed to GPIO inputs before the pin
> drivers are enabled. This is done to prevent accidental system resets,
> when a pin is connected to the main SoC's reset line.
>
> Signed-off-by: Sander Vanheule <sander@svanheule.net>
> ---
> drivers/mfd/Kconfig | 9 ++
> drivers/mfd/Makefile | 1 +
> drivers/mfd/rtl8231.c | 193 ++++++++++++++++++++++++++++++++++++
> include/linux/mfd/rtl8231.h | 71 +++++++++++++
> 4 files changed, 274 insertions(+)
> create mode 100644 drivers/mfd/rtl8231.c
> create mode 100644 include/linux/mfd/rtl8231.h
>
> diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
> index 6cec1858947b..e13e2df63fee 100644
> --- a/drivers/mfd/Kconfig
> +++ b/drivers/mfd/Kconfig
> @@ -1301,6 +1301,15 @@ config MFD_RDC321X
> southbridge which provides access to GPIOs and Watchdog using the
> southbridge PCI device configuration space.
>
> +config MFD_RTL8231
> + tristate "Realtek RTL8231 GPIO and LED expander"
> + select MFD_CORE
> + select REGMAP_MDIO
> + help
> + Support for the Realtek RTL8231 GPIO and LED expander.
> + Provides up to 37 GPIOs, 88 LEDs, and one PWM output.
> + When built as a module, this module will be named rtl8231.
> +
> config MFD_RT4831
> tristate "Richtek RT4831 four channel WLED and Display Bias Voltage"
> depends on I2C
> diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
> index 865e9f12faff..ba973382a20f 100644
> --- a/drivers/mfd/Makefile
> +++ b/drivers/mfd/Makefile
> @@ -252,6 +252,7 @@ obj-$(CONFIG_MFD_HI6421_PMIC) += hi6421-pmic-core.o
> obj-$(CONFIG_MFD_HI6421_SPMI) += hi6421-spmi-pmic.o
> obj-$(CONFIG_MFD_HI655X_PMIC) += hi655x-pmic.o
> obj-$(CONFIG_MFD_DLN2) += dln2.o
> +obj-$(CONFIG_MFD_RTL8231) += rtl8231.o
> obj-$(CONFIG_MFD_RT4831) += rt4831.o
> obj-$(CONFIG_MFD_RT5033) += rt5033.o
> obj-$(CONFIG_MFD_RT5120) += rt5120.o
> diff --git a/drivers/mfd/rtl8231.c b/drivers/mfd/rtl8231.c
> new file mode 100644
> index 000000000000..60d4a0feea5c
> --- /dev/null
> +++ b/drivers/mfd/rtl8231.c
> @@ -0,0 +1,193 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include <linux/bits.h>
> +#include <linux/bitfield.h>
> +#include <linux/delay.h>
> +#include <linux/gpio/consumer.h>
> +#include <linux/mfd/core.h>
> +#include <linux/mdio.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/property.h>
> +#include <linux/regmap.h>
Alphabetical please.
> +#include <linux/mfd/rtl8231.h>
> +
> +static bool rtl8231_volatile_reg(struct device *dev, unsigned int reg)
> +{
> + switch (reg) {
> + /*
> + * Registers with self-clearing bits, strapping pin values.
> + * Don't mark the data registers as volatile, since we need
> + * caching for the output values.
> + */
> + case RTL8231_REG_FUNC0:
> + case RTL8231_REG_FUNC1:
> + case RTL8231_REG_PIN_HI_CFG:
> + case RTL8231_REG_LED_END:
> + return true;
> + default:
> + return false;
> + }
> +}
> +
> +static const struct reg_field RTL8231_FIELD_LED_START = REG_FIELD(RTL8231_REG_FUNC0, 1, 1);
Why does this have to be global?
Variables should be lowercase.
> +static const struct mfd_cell rtl8231_cells[] = {
> + {
> + .name = "rtl8231-pinctrl",
> + },
> + {
> + .name = "rtl8231-leds",
> + .of_compatible = "realtek,rtl8231-leds",
> + },
> +};
This is a pretty tenuous MFD!
> +static int rtl8231_soft_reset(struct regmap *map)
s/map/regmap/
> +{
> + const unsigned int all_pins_mask = GENMASK(RTL8231_BITS_VAL - 1, 0);
> + unsigned int val;
> + int err;
> +
> + /* SOFT_RESET bit self-clears when done */
> + regmap_write_bits(map, RTL8231_REG_PIN_HI_CFG,
> + RTL8231_PIN_HI_CFG_SOFT_RESET, RTL8231_PIN_HI_CFG_SOFT_RESET);
> + err = regmap_read_poll_timeout(map, RTL8231_REG_PIN_HI_CFG, val,
> + !(val & RTL8231_PIN_HI_CFG_SOFT_RESET), 50, 1000);
> + if (err)
> + return err;
Do we have to scrunch these calls together?
> + regcache_mark_dirty(map);
> +
> + /*
> + * Chip reset results in a pin configuration that is a mix of LED and GPIO outputs.
> + * Select GPI functionality for all pins before enabling pin outputs.
> + */
> + regmap_write(map, RTL8231_REG_PIN_MODE0, all_pins_mask);
> + regmap_write(map, RTL8231_REG_GPIO_DIR0, all_pins_mask);
> + regmap_write(map, RTL8231_REG_PIN_MODE1, all_pins_mask);
> + regmap_write(map, RTL8231_REG_GPIO_DIR1, all_pins_mask);
> + regmap_write(map, RTL8231_REG_PIN_HI_CFG,
> + RTL8231_PIN_HI_CFG_MODE_MASK | RTL8231_PIN_HI_CFG_DIR_MASK);
> +
> + return 0;
> +}
> +
> +static int rtl8231_init(struct device *dev, struct regmap *map)
> +{
> + struct regmap_field *led_start;
> + unsigned int started;
> + unsigned int val;
If this is used for only one thing, it makes sense to use better
nomenclature that refers to that thing.
> + int err;
> +
> + err = regmap_read(map, RTL8231_REG_FUNC1, &val);
> + if (err) {
> + dev_err(dev, "failed to read READY_CODE\n");
> + return err;
> + }
> +
> + val = FIELD_GET(RTL8231_FUNC1_READY_CODE_MASK, val);
> + if (val != RTL8231_FUNC1_READY_CODE_VALUE) {
> + dev_err(dev, "RTL8231 not present or ready 0x%x != 0x%x\n",
> + val, RTL8231_FUNC1_READY_CODE_VALUE);
> + return -ENODEV;
> + }
> +
> + led_start = dev_get_drvdata(dev);
> + err = regmap_field_read(led_start, &started);
> + if (err)
> + return err;
> +
> + if (!started) {
Reverse the logic and exit early if 'started'.
> + err = rtl8231_soft_reset(map);
> + if (err)
> + return err;
'\n' here.
> + /* LED_START enables power to output pins, and starts the LED engine */
> + err = regmap_field_force_write(led_start, 1);
> + }
> +
> + return err;
> +}
> +
> +static const struct regmap_config rtl8231_mdio_regmap_config = {
> + .val_bits = RTL8231_BITS_VAL,
> + .reg_bits = RTL8231_BITS_REG,
> + .volatile_reg = rtl8231_volatile_reg,
> + .max_register = RTL8231_REG_COUNT - 1,
> + .use_single_read = true,
> + .use_single_write = true,
> + .reg_format_endian = REGMAP_ENDIAN_BIG,
> + .val_format_endian = REGMAP_ENDIAN_BIG,
> + /* Cannot use REGCACHE_FLAT because it's not smart enough about cache invalidation */
> + .cache_type = REGCACHE_MAPLE,
> +};
> +
> +static int rtl8231_mdio_probe(struct mdio_device *mdiodev)
> +{
> + struct device *dev = &mdiodev->dev;
> + struct regmap_field *led_start;
> + struct regmap *map;
> + int err;
> +
> + map = devm_regmap_init_mdio(mdiodev, &rtl8231_mdio_regmap_config);
> + if (IS_ERR(map)) {
> + dev_err(dev, "failed to init regmap\n");
> + return PTR_ERR(map);
> + }
> +
> + led_start = devm_regmap_field_alloc(dev, map, RTL8231_FIELD_LED_START);
> + if (IS_ERR(led_start))
> + return PTR_ERR(led_start);
Why do we need to do LED specific actions in the core driver?
> + dev_set_drvdata(dev, led_start);
> +
> + mdiodev->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
> + if (IS_ERR(mdiodev->reset_gpio))
> + return PTR_ERR(mdiodev->reset_gpio);
> +
> + device_property_read_u32(dev, "reset-assert-delay", &mdiodev->reset_assert_delay);
> + device_property_read_u32(dev, "reset-deassert-delay", &mdiodev->reset_deassert_delay);
> +
> + err = rtl8231_init(dev, map);
> + if (err)
> + return err;
> +
> + return devm_mfd_add_devices(dev, PLATFORM_DEVID_AUTO, rtl8231_cells,
> + ARRAY_SIZE(rtl8231_cells), NULL, 0, NULL);
Odd tabbing. Please line-up with the '(' like usual.
> +}
> +
> +__maybe_unused static int rtl8231_suspend(struct device *dev)
The __maybe_unused comes after the "static int" part.
> +{
> + struct regmap_field *led_start = dev_get_drvdata(dev);
> +
> + return regmap_field_force_write(led_start, 0);
> +}
> +
> +__maybe_unused static int rtl8231_resume(struct device *dev)
> +{
> + struct regmap_field *led_start = dev_get_drvdata(dev);
> +
> + return regmap_field_force_write(led_start, 1);
> +}
> +
> +static SIMPLE_DEV_PM_OPS(rtl8231_pm_ops, rtl8231_suspend, rtl8231_resume);
> +
> +static const struct of_device_id rtl8231_of_match[] = {
> + { .compatible = "realtek,rtl8231" },
> + {}
> +};
> +MODULE_DEVICE_TABLE(of, rtl8231_of_match);
> +
> +static struct mdio_driver rtl8231_mdio_driver = {
> + .mdiodrv.driver = {
> + .name = "rtl8231-expander",
> + .of_match_table = rtl8231_of_match,
> + .pm = pm_ptr(&rtl8231_pm_ops),
> + },
> + .probe = rtl8231_mdio_probe,
> +};
> +mdio_module_driver(rtl8231_mdio_driver);
> +
> +MODULE_AUTHOR("Sander Vanheule <sander@svanheule.net>");
> +MODULE_DESCRIPTION("Realtek RTL8231 GPIO and LED expander");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/mfd/rtl8231.h b/include/linux/mfd/rtl8231.h
> new file mode 100644
> index 000000000000..003eda3797a3
> --- /dev/null
> +++ b/include/linux/mfd/rtl8231.h
> @@ -0,0 +1,71 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Register definitions the RTL8231 GPIO and LED expander chip
> + */
> +
> +#ifndef __LINUX_MFD_RTL8231_H
> +#define __LINUX_MFD_RTL8231_H
> +
> +#include <linux/bits.h>
> +
> +/*
> + * Registers addresses are 5 bit, values are 16 bit
> + * Also define a duplicated range of virtual addresses, to enable
> + * different read/write behaviour on the GPIO data registers
> + */
> +#define RTL8231_BITS_VAL 16
> +#define RTL8231_BITS_REG 5
> +
> +/* Chip control */
> +#define RTL8231_REG_FUNC0 0x00
> +#define RTL8231_FUNC0_SCAN_MODE BIT(0)
> +#define RTL8231_FUNC0_SCAN_SINGLE 0
> +#define RTL8231_FUNC0_SCAN_BICOLOR BIT(0)
> +
> +#define RTL8231_REG_FUNC1 0x01
> +#define RTL8231_FUNC1_READY_CODE_VALUE 0x37
> +#define RTL8231_FUNC1_READY_CODE_MASK GENMASK(9, 4)
> +#define RTL8231_FUNC1_DEBOUNCE_MASK GENMASK(15, 10)
> +
> +/* Pin control */
> +#define RTL8231_REG_PIN_MODE0 0x02
> +#define RTL8231_REG_PIN_MODE1 0x03
> +
> +#define RTL8231_PIN_MODE_LED 0
> +#define RTL8231_PIN_MODE_GPIO 1
> +
> +/* Pin high config: pin and GPIO control for pins 32-26 */
> +#define RTL8231_REG_PIN_HI_CFG 0x04
> +#define RTL8231_PIN_HI_CFG_MODE_MASK GENMASK(4, 0)
> +#define RTL8231_PIN_HI_CFG_DIR_MASK GENMASK(9, 5)
> +#define RTL8231_PIN_HI_CFG_INV_MASK GENMASK(14, 10)
> +#define RTL8231_PIN_HI_CFG_SOFT_RESET BIT(15)
> +
> +/* GPIO control registers */
> +#define RTL8231_REG_GPIO_DIR0 0x05
> +#define RTL8231_REG_GPIO_DIR1 0x06
> +#define RTL8231_REG_GPIO_INVERT0 0x07
> +#define RTL8231_REG_GPIO_INVERT1 0x08
> +
> +#define RTL8231_GPIO_DIR_IN 1
> +#define RTL8231_GPIO_DIR_OUT 0
> +
> +/*
> + * GPIO data registers
> + * Only the output data can be written to these registers, and only the input
> + * data can be read.
> + */
> +#define RTL8231_REG_GPIO_DATA0 0x1c
> +#define RTL8231_REG_GPIO_DATA1 0x1d
> +#define RTL8231_REG_GPIO_DATA2 0x1e
> +#define RTL8231_PIN_HI_DATA_MASK GENMASK(4, 0)
> +
> +/* LED control base registers */
> +#define RTL8231_REG_LED0_BASE 0x09
> +#define RTL8231_REG_LED1_BASE 0x10
> +#define RTL8231_REG_LED2_BASE 0x17
> +#define RTL8231_REG_LED_END 0x1b
> +
> +#define RTL8231_REG_COUNT 0x1f
> +
> +#endif /* __LINUX_MFD_RTL8231_H */
> --
> 2.51.0
>
>
--
Lee Jones [李琼斯]
^ permalink raw reply [flat|nested] 22+ messages in thread
end of thread, other threads:[~2025-11-06 16:33 UTC | newest]
Thread overview: 22+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-10-21 14:23 [PATCH v6 0/8] RTL8231 GPIO expander support Sander Vanheule
2025-10-21 14:23 ` [PATCH v6 1/8] gpio: regmap: Force writes for aliased data regs Sander Vanheule
2025-10-21 14:23 ` [PATCH v6 2/8] gpio: regmap: Bypass cache for aliased inputs Sander Vanheule
2025-10-23 12:06 ` Bartosz Golaszewski
2025-10-21 14:23 ` [PATCH v6 3/8] dt-bindings: leds: Binding for RTL8231 scan matrix Sander Vanheule
2025-10-26 21:59 ` Rob Herring
2025-10-27 17:12 ` Sander Vanheule
2025-10-21 14:23 ` [PATCH v6 4/8] dt-bindings: mfd: Binding for RTL8231 Sander Vanheule
2025-10-26 22:04 ` Rob Herring
2025-10-21 14:24 ` [PATCH v6 5/8] mfd: Add RTL8231 core device Sander Vanheule
2025-11-06 16:33 ` Lee Jones
2025-10-21 14:24 ` [PATCH v6 6/8] pinctrl: Add RTL8231 pin control and GPIO support Sander Vanheule
2025-10-22 1:47 ` kernel test robot
2025-10-22 5:01 ` kernel test robot
2025-10-22 7:42 ` Linus Walleij
2025-10-22 7:52 ` Linus Walleij
2025-10-22 8:24 ` Sander Vanheule
2025-10-21 14:24 ` [PATCH v6 7/8] leds: Add support for RTL8231 LED scan matrix Sander Vanheule
2025-10-21 14:24 ` [PATCH v6 8/8] MAINTAINERS: Add RTL8231 MFD driver Sander Vanheule
2025-10-23 9:05 ` [PATCH v6 0/8] RTL8231 GPIO expander support Bartosz Golaszewski
2025-10-23 9:09 ` Sander Vanheule
2025-10-23 12:05 ` (subset) " Bartosz Golaszewski
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