[v3,1/3] leds: ktd2692: move ExpressWire code to library

Message ID	20240120-ktd2801-v3-1-fe2cbafffb21@skole.hr (mailing list archive)
State	New, archived
Headers	show Return-Path: <dri-devel-bounces@lists.freedesktop.org> From: =?utf-8?q?Duje_Mihanovi=C4=87?= <duje.mihanovic@skole.hr> Date: Sat, 20 Jan 2024 22:26:43 +0100 Subject: [PATCH v3 1/3] leds: ktd2692: move ExpressWire code to library MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Message-Id: <20240120-ktd2801-v3-1-fe2cbafffb21@skole.hr> References: <20240120-ktd2801-v3-0-fe2cbafffb21@skole.hr> In-Reply-To: <20240120-ktd2801-v3-0-fe2cbafffb21@skole.hr> To: Lee Jones <lee@kernel.org>, Daniel Thompson <daniel.thompson@linaro.org>, Jingoo Han <jingoohan1@gmail.com>, Pavel Machek <pavel@ucw.cz>, Rob Herring <robh+dt@kernel.org>, Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Conor Dooley <conor+dt@kernel.org>, Helge Deller <deller@gmx.de>, Linus Walleij <linus.walleij@linaro.org> Precedence: list Cc: devicetree@vger.kernel.org, linux-fbdev@vger.kernel.org, =?utf-8?q?Duje_?= =?utf-8?q?Mihanovi=C4=87?= <duje.mihanovic@skole.hr>, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, ~postmarketos/upstreaming@lists.sr.ht, phone-devel@vger.kernel.org, Karel Balej <balejk@matfyz.cz>, linux-leds@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" <dri-devel-bounces@lists.freedesktop.org>
Series	Kinetic ExpressWire library and KTD2801 backlight driver \| expand [v3,0/3] Kinetic ExpressWire library and KTD2801 backlight driver [v3,1/3] leds: ktd2692: move ExpressWire code to library [v3,2/3] dt-bindings: backlight: add Kinetic KTD2801 binding [v3,3/3] backlight: Add Kinetic KTD2801 backlight support

diff --git a/MAINTAINERS b/MAINTAINERS index a7c4cf8201e0..87b12d2448a0 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7902,6 +7902,13 @@ S: Maintained T: git git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat.git F: fs/exfat/ +EXPRESSWIRE PROTOCOL LIBRARY +M: Duje Mihanović <duje.mihanovic@skole.hr> +L: linux-leds@vger.kernel.org +S: Maintained +F: drivers/leds/leds-expresswire.c +F: include/linux/leds-expresswire.h + EXT2 FILE SYSTEM M: Jan Kara <jack@suse.com> L: linux-ext4@vger.kernel.org diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 6292fddcc55c..d29b6823e7d1 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -181,6 +181,9 @@ config LEDS_EL15203000 To compile this driver as a module, choose M here: the module will be called leds-el15203000. +config LEDS_EXPRESSWIRE + bool + config LEDS_TURRIS_OMNIA tristate "LED support for CZ.NIC's Turris Omnia" depends on LEDS_CLASS_MULTICOLOR diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index d7348e8bc019..a63a07d01c6f 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -89,6 +89,9 @@ obj-$(CONFIG_LEDS_WM831X_STATUS) += leds-wm831x-status.o obj-$(CONFIG_LEDS_WM8350) += leds-wm8350.o obj-$(CONFIG_LEDS_WRAP) += leds-wrap.o +# Kinetic ExpressWire Protocol +obj-$(CONFIG_LEDS_EXPRESSWIRE) += leds-expresswire.o + # LED SPI Drivers obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig index 4e08dbc05709..526c1d063cd8 100644 --- a/drivers/leds/flash/Kconfig +++ b/drivers/leds/flash/Kconfig @@ -24,6 +24,7 @@ config LEDS_KTD2692 tristate "LED support for Kinetic KTD2692 flash LED controller" depends on OF depends on GPIOLIB || COMPILE_TEST + select LEDS_EXPRESSWIRE help This option enables support for Kinetic KTD2692 LED flash connected through ExpressWire interface. diff --git a/drivers/leds/flash/leds-ktd2692.c b/drivers/leds/flash/leds-ktd2692.c index 598eee5daa52..8c17de3d621f 100644 --- a/drivers/leds/flash/leds-ktd2692.c +++ b/drivers/leds/flash/leds-ktd2692.c @@ -9,6 +9,7 @@ #include <linux/delay.h> #include <linux/err.h> #include <linux/gpio/consumer.h> +#include <linux/leds-expresswire.h> #include <linux/led-class-flash.h> #include <linux/module.h> #include <linux/mutex.h> @@ -48,11 +49,6 @@ /* KTD2692 default length of name */ #define KTD2692_NAME_LENGTH 20 -enum ktd2692_bitset { - KTD2692_LOW = 0, - KTD2692_HIGH, -}; - /* Movie / Flash Mode Control */ enum ktd2692_led_mode { KTD2692_MODE_DISABLE = 0, /* default */ @@ -71,7 +67,19 @@ struct ktd2692_led_config_data { enum led_brightness max_brightness; }; +const struct expresswire_timing ktd2692_timing = { + .poweroff_us = KTD2692_TIME_RESET_US, + .data_start_us = KTD2692_TIME_DATA_START_TIME_US, + .end_of_data_low_us = KTD2692_TIME_LOW_END_OF_DATA_US, + .end_of_data_high_us = KTD2692_TIME_HIGH_END_OF_DATA_US, + .short_bitset_us = KTD2692_TIME_SHORT_BITSET_US, + .long_bitset_us = KTD2692_TIME_LONG_BITSET_US +}; + struct ktd2692_context { + /* Common ExpressWire properties (ctrl GPIO and timing) */ + struct expresswire_common_props props; + /* Related LED Flash class device */ struct led_classdev_flash fled_cdev; @@ -80,7 +88,6 @@ struct ktd2692_context { struct regulator *regulator; struct gpio_desc *aux_gpio; - struct gpio_desc *ctrl_gpio; enum ktd2692_led_mode mode; enum led_brightness torch_brightness; @@ -92,65 +99,14 @@ static struct ktd2692_context *fled_cdev_to_led( return container_of(fled_cdev, struct ktd2692_context, fled_cdev); } -static void ktd2692_expresswire_start(struct ktd2692_context *led) -{ - gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH); - udelay(KTD2692_TIME_DATA_START_TIME_US); -} - -static void ktd2692_expresswire_reset(struct ktd2692_context *led) -{ - gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW); - udelay(KTD2692_TIME_RESET_US); -} - -static void ktd2692_expresswire_end(struct ktd2692_context *led) -{ - gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW); - udelay(KTD2692_TIME_LOW_END_OF_DATA_US); - gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH); - udelay(KTD2692_TIME_HIGH_END_OF_DATA_US); -} - -static void ktd2692_expresswire_set_bit(struct ktd2692_context *led, bool bit) -{ - /* - * The Low Bit(0) and High Bit(1) is based on a time detection - * algorithm between time low and time high - * Time_(L_LB) : Low time of the Low Bit(0) - * Time_(H_LB) : High time of the LOW Bit(0) - * Time_(L_HB) : Low time of the High Bit(1) - * Time_(H_HB) : High time of the High Bit(1) - * - * It can be simplified to: - * Low Bit(0) : 2 * Time_(H_LB) < Time_(L_LB) - * High Bit(1) : 2 * Time_(L_HB) < Time_(H_HB) - * HIGH ___ ____ _.. _________ ___ - * |_________| |_.. |____| |__| - * LOW <L_LB> <H_LB> <L_HB> <H_HB> - * [ Low Bit (0) ] [ High Bit(1) ] - */ - if (bit) { - gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW); - udelay(KTD2692_TIME_SHORT_BITSET_US); - gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH); - udelay(KTD2692_TIME_LONG_BITSET_US); - } else { - gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW); - udelay(KTD2692_TIME_LONG_BITSET_US); - gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH); - udelay(KTD2692_TIME_SHORT_BITSET_US); - } -} - static void ktd2692_expresswire_write(struct ktd2692_context *led, u8 value) { int i; - ktd2692_expresswire_start(led); + expresswire_start(&led->props); for (i = 7; i >= 0; i--) - ktd2692_expresswire_set_bit(led, value & BIT(i)); - ktd2692_expresswire_end(led); + expresswire_set_bit(&led->props, value & BIT(i)); + expresswire_end(&led->props); } static int ktd2692_led_brightness_set(struct led_classdev *led_cdev, @@ -163,7 +119,7 @@ static int ktd2692_led_brightness_set(struct led_classdev *led_cdev, if (brightness == LED_OFF) { led->mode = KTD2692_MODE_DISABLE; - gpiod_direction_output(led->aux_gpio, KTD2692_LOW); + gpiod_direction_output(led->aux_gpio, 0); } else { ktd2692_expresswire_write(led, brightness | KTD2692_REG_MOVIE_CURRENT_BASE); @@ -191,10 +147,10 @@ static int ktd2692_led_flash_strobe_set(struct led_classdev_flash *fled_cdev, | KTD2692_REG_FLASH_TIMEOUT_BASE); led->mode = KTD2692_MODE_FLASH; - gpiod_direction_output(led->aux_gpio, KTD2692_HIGH); + gpiod_direction_output(led->aux_gpio, 1); } else { led->mode = KTD2692_MODE_DISABLE; - gpiod_direction_output(led->aux_gpio, KTD2692_LOW); + gpiod_direction_output(led->aux_gpio, 0); } ktd2692_expresswire_write(led, led->mode | KTD2692_REG_MODE_BASE); @@ -247,8 +203,8 @@ static void ktd2692_init_flash_timeout(struct led_classdev_flash *fled_cdev, static void ktd2692_setup(struct ktd2692_context *led) { led->mode = KTD2692_MODE_DISABLE; - ktd2692_expresswire_reset(led); - gpiod_direction_output(led->aux_gpio, KTD2692_LOW); + expresswire_power_off(&led->props); + gpiod_direction_output(led->aux_gpio, 0); ktd2692_expresswire_write(led, (KTD2692_MM_MIN_CURR_THRESHOLD_SCALE - 1) | KTD2692_REG_MM_MIN_CURR_THRESHOLD_BASE); @@ -277,8 +233,8 @@ static int ktd2692_parse_dt(struct ktd2692_context *led, struct device *dev, if (!np) return -ENXIO; - led->ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_ASIS); - ret = PTR_ERR_OR_ZERO(led->ctrl_gpio); + led->props.ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_ASIS); + ret = PTR_ERR_OR_ZERO(led->props.ctrl_gpio); if (ret) return dev_err_probe(dev, ret, "cannot get ctrl-gpios\n"); @@ -412,6 +368,7 @@ static struct platform_driver ktd2692_driver = { module_platform_driver(ktd2692_driver); +MODULE_IMPORT_NS(EXPRESSWIRE); MODULE_AUTHOR("Ingi Kim <ingi2.kim@samsung.com>"); MODULE_DESCRIPTION("Kinetic KTD2692 LED driver"); MODULE_LICENSE("GPL v2"); diff --git a/drivers/leds/leds-expresswire.c b/drivers/leds/leds-expresswire.c new file mode 100644 index 000000000000..88e76c968cf0 --- /dev/null +++ b/drivers/leds/leds-expresswire.c @@ -0,0 +1,59 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Shared library for Kinetic's ExpressWire protocol. + * This protocol works by pulsing the ExpressWire IC's control GPIO. + * ktd2692 and ktd2801 are known to use this protocol. + */ + +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/leds-expresswire.h> + +void expresswire_power_off(struct expresswire_common_props *props) +{ + gpiod_set_value_cansleep(props->ctrl_gpio, 0); + usleep_range(props->timing.poweroff_us, props->timing.poweroff_us * 2); +} +EXPORT_SYMBOL_NS_GPL(expresswire_power_off, EXPRESSWIRE); + +void expresswire_enable(struct expresswire_common_props *props) +{ + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.detect_delay_us); + gpiod_set_value(props->ctrl_gpio, 0); + udelay(props->timing.detect_us); + gpiod_set_value(props->ctrl_gpio, 1); +} +EXPORT_SYMBOL_NS_GPL(expresswire_enable, EXPRESSWIRE); + +void expresswire_start(struct expresswire_common_props *props) +{ + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.data_start_us); +} +EXPORT_SYMBOL_NS_GPL(expresswire_start, EXPRESSWIRE); + +void expresswire_end(struct expresswire_common_props *props) +{ + gpiod_set_value(props->ctrl_gpio, 0); + udelay(props->timing.end_of_data_low_us); + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.end_of_data_high_us); +} +EXPORT_SYMBOL_NS_GPL(expresswire_end, EXPRESSWIRE); + +void expresswire_set_bit(struct expresswire_common_props *props, bool bit) +{ + if (bit) { + gpiod_set_value(props->ctrl_gpio, 0); + udelay(props->timing.short_bitset_us); + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.long_bitset_us); + } else { + gpiod_set_value(props->ctrl_gpio, 0); + udelay(props->timing.long_bitset_us); + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.short_bitset_us); + } +} +EXPORT_SYMBOL_NS_GPL(expresswire_set_bit, EXPRESSWIRE); diff --git a/include/linux/leds-expresswire.h b/include/linux/leds-expresswire.h new file mode 100644 index 000000000000..b5aad0556cb8 --- /dev/null +++ b/include/linux/leds-expresswire.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Shared library for Kinetic's ExpressWire protocol. + * This protocol works by pulsing the ExpressWire IC's control GPIO. + * ktd2692 and ktd2801 are known to use this protocol. + */ + +#ifndef _LEDS_EXPRESSWIRE_H +#define _LEDS_EXPRESSWIRE_H + +#include <linux/gpio/consumer.h> + +struct expresswire_timing { + unsigned long poweroff_us; + unsigned long detect_delay_us; + unsigned long detect_us; + unsigned long data_start_us; + unsigned long end_of_data_low_us; + unsigned long end_of_data_high_us; + unsigned long short_bitset_us; + unsigned long long_bitset_us; +}; + +struct expresswire_common_props { + struct gpio_desc *ctrl_gpio; + struct expresswire_timing timing; +}; + +extern void expresswire_power_off(struct expresswire_common_props *props); +extern void expresswire_enable(struct expresswire_common_props *props); +extern void expresswire_start(struct expresswire_common_props *props); +extern void expresswire_end(struct expresswire_common_props *props); +extern void expresswire_set_bit(struct expresswire_common_props *props, bool bit); + +#endif /* _LEDS_EXPRESSWIRE_H */

[v3,1/3] leds: ktd2692: move ExpressWire code to library

Commit Message

Comments

Patch