From patchwork Thu Jan 25 15:30:53 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Duje_Mihanovi=C4=87?= X-Patchwork-Id: 766110 Received: from mx.skole.hr (mx1.hosting.skole.hr [161.53.165.185]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F0ED87316F; Thu, 25 Jan 2024 15:32:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=161.53.165.185 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706196727; cv=none; b=eLOdyQysV9hgGE4aWPG8AKXeNg4cvMi0h63ksgajK0CTkwluAbdDYBw8r/JDRIKW5XM36wMt+EiL0hx6K0wXbj8rF+YgHH9LkB+qZqZUfpOmCUSMvYUtVYlhR6o38DMKkpBRGKUeRhWEDb93wf8B/ZjNn4DbUOuNToSVnM7hp3w= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706196727; c=relaxed/simple; bh=EmBtZVpm+2jJo0+oBnQB1a+nHfZMWJwr8ePwkRQqIvM=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=BWNBwtZ7mgALgCU/d+CF06PvlvuQ1gFFfHTbHNtMO7YBYgvnm9BK/jqKV/54eKtuuMiqNte4/keh96tQMyxsttk5iFVOU3DUvY4O3YOtotOGevZZ4bxpgfSRSSYC3YQI/guiQh36NRIEg69py3stCb3tExrP++82vjXjgyHQTKU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=skole.hr; spf=pass smtp.mailfrom=skole.hr; arc=none smtp.client-ip=161.53.165.185 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=skole.hr Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=skole.hr Received: from mx1.hosting.skole.hr (localhost.localdomain [127.0.0.1]) by mx.skole.hr (mx.skole.hr) with ESMTP id 104DF84F6E; Thu, 25 Jan 2024 16:31:56 +0100 (CET) From: =?utf-8?q?Duje_Mihanovi=C4=87?= Date: Thu, 25 Jan 2024 16:30:53 +0100 Subject: [PATCH v5 1/4] leds: introduce ExpressWire library Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20240125-ktd2801-v5-1-e22da232a825@skole.hr> References: <20240125-ktd2801-v5-0-e22da232a825@skole.hr> In-Reply-To: <20240125-ktd2801-v5-0-e22da232a825@skole.hr> To: Lee Jones , Daniel Thompson , Jingoo Han , Pavel Machek , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Helge Deller , Linus Walleij Cc: Karel Balej , ~postmarketos/upstreaming@lists.sr.ht, phone-devel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, =?utf-8?q?Duje_?= =?utf-8?q?Mihanovi=C4=87?= X-Mailer: b4 0.12.4 X-Developer-Signature: v=1; a=openpgp-sha256; l=6456; i=duje.mihanovic@skole.hr; h=from:subject:message-id; bh=EmBtZVpm+2jJo0+oBnQB1a+nHfZMWJwr8ePwkRQqIvM=; b=owEBbQKS/ZANAwAIAZoRnrBCLZbhAcsmYgBlsn7DfN3tI6caY5seGs5+QL9PGrkwNvXOL0Sue VbwtyVxGSWJAjMEAAEIAB0WIQRT351NnD/hEPs2LXiaEZ6wQi2W4QUCZbJ+wwAKCRCaEZ6wQi2W 4b2uEACQ+Al72XGNOC52NpzDW/JVVVe3UODtl272aLQfQSnnX3AHgIj34cZBt1PFFquUnRAJnDr itqposRDO5747+OdD4dCDEObOrr4EjJvtr1tLnAzo+2OaT6L4HVLWSnTY6GgWrdHx5fUK2JHV9U gMmNQeycJoPwo/7kY7WtGzlJJrTDldS9UtL9V5LnWG5cXsN9ZNb5suFyvEYj7nrHJTqVXg2djRs qd7m/1/fxkpJPV1qm2YUeYlTp4e/ZPVshYwtSHEWzrrAqsKIt5nDCsNivPN4JX094i6rTqdumZu 7W874oq0MuNJ0bGQnoL067KGbkwoqfyo0XwgawcZHNp8ibEM/yoCvBpiTMzhCR1CP6fQoGWKPLT t0JGjAW/17synjXDVXXAv4VCZMCqmUgL58Rgo1q8ChRQWM2yTkHskjuLh84nwoc2DhMP059IO68 1j2lM2i5wbMBvYxM4ZoCXS37vR7CUdMODqHLGTVuUGnaxeDl4CPiLRvaT9aPjErAoeTq190NQCz kHNP51PxX/ozV+ouyR7muDWwzHpEnLyFIZ0xtWVkyhOb1korptaga37qUphyBtrjF3GYeH1NLJE 9YSEG0TPxhy1/BI9dFvQ4ZMem1nLdsSphyozRy4VKUdAkU23tEaPWMA4D6Hfvdx+Kpco6QbBACo D2tfRksekaUFlHQ== X-Developer-Key: i=duje.mihanovic@skole.hr; a=openpgp; fpr=53DF9D4D9C3FE110FB362D789A119EB0422D96E1 The ExpressWire protocol is shared between at least KTD2692 and KTD2801 with slight differences such as timings and the former not having a defined set of pulses for enabling the protocol (possibly because it does not support PWM unlike KTD2801). Despite these differences the ExpressWire handling code can be shared between the two, so in preparation for adding KTD2801 support introduce a library implementing this protocol. Suggested-by: Daniel Thompson Reviewed-by: Linus Walleij Reviewed-by: Daniel Thompson Signed-off-by: Duje Mihanović --- MAINTAINERS | 7 +++++ drivers/leds/Kconfig | 4 +++ drivers/leds/Makefile | 3 ++ drivers/leds/leds-expresswire.c | 68 ++++++++++++++++++++++++++++++++++++++++ include/linux/leds-expresswire.h | 36 +++++++++++++++++++++ 5 files changed, 118 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index 8d1052fa6a69..e1c83e0e837a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7979,6 +7979,13 @@ 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 +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 L: linux-ext4@vger.kernel.org diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index d721b254e1e4..64bb2de237e9 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -186,6 +186,10 @@ config LEDS_EL15203000 To compile this driver as a module, choose M here: the module will be called leds-el15203000. +config LEDS_EXPRESSWIRE + bool + depends on GPIOLIB + 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 ce07dc295ff0..effdfc6f1e95 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -91,6 +91,9 @@ 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/leds-expresswire.c b/drivers/leds/leds-expresswire.c new file mode 100644 index 000000000000..89e147b0e019 --- /dev/null +++ b/drivers/leds/leds-expresswire.c @@ -0,0 +1,68 @@ +// 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 +#include +#include + +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); + +void expresswire_write_u8(struct expresswire_common_props *props, u8 val) +{ + expresswire_start(props); + for (int i = 7; i >= 0; i--) + expresswire_set_bit(props, val & BIT(i)); + expresswire_end(props); +} +EXPORT_SYMBOL_NS_GPL(expresswire_write_u8, EXPRESSWIRE); diff --git a/include/linux/leds-expresswire.h b/include/linux/leds-expresswire.h new file mode 100644 index 000000000000..3c61902ccac8 --- /dev/null +++ b/include/linux/leds-expresswire.h @@ -0,0 +1,36 @@ +/* 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 + +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; +}; + +void expresswire_power_off(struct expresswire_common_props *props); +void expresswire_enable(struct expresswire_common_props *props); +void expresswire_start(struct expresswire_common_props *props); +void expresswire_end(struct expresswire_common_props *props); +void expresswire_set_bit(struct expresswire_common_props *props, bool bit); +void expresswire_write_u8(struct expresswire_common_props *props, u8 val); + +#endif /* _LEDS_EXPRESSWIRE_H */ From patchwork Thu Jan 25 15:30:56 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Duje_Mihanovi=C4=87?= X-Patchwork-Id: 766109 Received: from mx.skole.hr (mx2.hosting.skole.hr [161.53.165.186]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2C89A73172; 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a=openpgp; fpr=53DF9D4D9C3FE110FB362D789A119EB0422D96E1 KTD2801 is a LED backlight driver IC found in samsung,coreprimevelte. The brightness can be set using PWM or the ExpressWire protocol. Add support for the KTD2801. Reviewed-by: Linus Walleij Reviewed-by: Daniel Thompson Signed-off-by: Duje Mihanović --- MAINTAINERS | 6 ++ drivers/video/backlight/Kconfig | 7 ++ drivers/video/backlight/Makefile | 1 + drivers/video/backlight/ktd2801-backlight.c | 128 ++++++++++++++++++++++++++++ 4 files changed, 142 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index e1c83e0e837a..01cd1a460907 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12052,6 +12052,12 @@ S: Maintained F: Documentation/devicetree/bindings/leds/backlight/kinetic,ktd253.yaml F: drivers/video/backlight/ktd253-backlight.c +KTD2801 BACKLIGHT DRIVER +M: Duje Mihanović +S: Maintained +F: Documentation/devicetree/bindings/leds/backlight/kinetic,ktd2801.yaml +F: drivers/video/backlight/ktd2801-backlight.c + KTEST M: Steven Rostedt M: John Hawley diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index ea2d0d69bd8c..230bca07b09d 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -183,6 +183,13 @@ config BACKLIGHT_KTD253 which is a 1-wire GPIO-controlled backlight found in some mobile phones. +config BACKLIGHT_KTD2801 + tristate "Backlight Driver for Kinetic KTD2801" + select LEDS_EXPRESSWIRE + help + Say Y to enable the backlight driver for the Kinetic KTD2801 1-wire + GPIO-controlled backlight found in Samsung Galaxy Core Prime VE LTE. + config BACKLIGHT_KTZ8866 tristate "Backlight Driver for Kinetic KTZ8866" depends on I2C diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index 06966cb20459..8d2cb252042d 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -34,6 +34,7 @@ obj-$(CONFIG_BACKLIGHT_HP680) += hp680_bl.o obj-$(CONFIG_BACKLIGHT_HP700) += jornada720_bl.o obj-$(CONFIG_BACKLIGHT_IPAQ_MICRO) += ipaq_micro_bl.o obj-$(CONFIG_BACKLIGHT_KTD253) += ktd253-backlight.o +obj-$(CONFIG_BACKLIGHT_KTD2801) += ktd2801-backlight.o obj-$(CONFIG_BACKLIGHT_KTZ8866) += ktz8866.o obj-$(CONFIG_BACKLIGHT_LM3533) += lm3533_bl.o obj-$(CONFIG_BACKLIGHT_LM3630A) += lm3630a_bl.o diff --git a/drivers/video/backlight/ktd2801-backlight.c b/drivers/video/backlight/ktd2801-backlight.c new file mode 100644 index 000000000000..c020acff40f1 --- /dev/null +++ b/drivers/video/backlight/ktd2801-backlight.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Datasheet: + * https://www.kinet-ic.com/uploads/web/KTD2801/KTD2801-04b.pdf + */ +#include +#include +#include +#include +#include + +#define KTD2801_DEFAULT_BRIGHTNESS 100 +#define KTD2801_MAX_BRIGHTNESS 255 + +/* These values have been extracted from Samsung's driver. */ +const struct expresswire_timing ktd2801_timing = { + .poweroff_us = 2600, + .detect_delay_us = 150, + .detect_us = 270, + .data_start_us = 5, + .short_bitset_us = 5, + .long_bitset_us = 15, + .end_of_data_low_us = 10, + .end_of_data_high_us = 350 +}; + +struct ktd2801_backlight { + struct expresswire_common_props props; + struct backlight_device *bd; + bool was_on; +}; + +static int ktd2801_update_status(struct backlight_device *bd) +{ + struct ktd2801_backlight *ktd2801 = bl_get_data(bd); + u8 brightness = (u8) backlight_get_brightness(bd); + + if (backlight_is_blank(bd)) { + expresswire_power_off(&ktd2801->props); + ktd2801->was_on = false; + return 0; + } + + if (!ktd2801->was_on) { + expresswire_enable(&ktd2801->props); + ktd2801->was_on = true; + } + + expresswire_write_u8(&ktd2801->props, brightness); + + return 0; +} + +static const struct backlight_ops ktd2801_backlight_ops = { + .update_status = ktd2801_update_status, +}; + +static int ktd2801_backlight_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct backlight_device *bd; + struct ktd2801_backlight *ktd2801; + u32 brightness, max_brightness; + int ret; + + ktd2801 = devm_kzalloc(dev, sizeof(*ktd2801), GFP_KERNEL); + if (!ktd2801) + return -ENOMEM; + ktd2801->was_on = true; + ktd2801->props.timing = ktd2801_timing; + + ret = device_property_read_u32(dev, "max-brightness", &max_brightness); + if (ret) + max_brightness = KTD2801_MAX_BRIGHTNESS; + if (max_brightness > KTD2801_MAX_BRIGHTNESS) { + dev_err(dev, "illegal max brightness specified\n"); + max_brightness = KTD2801_MAX_BRIGHTNESS; + } + + ret = device_property_read_u32(dev, "default-brightness", &brightness); + if (ret) + brightness = KTD2801_DEFAULT_BRIGHTNESS; + if (brightness > max_brightness) { + dev_err(dev, "default brightness exceeds max\n"); + brightness = max_brightness; + } + + ktd2801->props.ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_OUT_HIGH); + if (IS_ERR(ktd2801->props.ctrl_gpio)) + return dev_err_probe(dev, PTR_ERR(ktd2801->props.ctrl_gpio), + "failed to get backlight GPIO"); + gpiod_set_consumer_name(ktd2801->props.ctrl_gpio, dev_name(dev)); + + bd = devm_backlight_device_register(dev, dev_name(dev), dev, ktd2801, + &ktd2801_backlight_ops, NULL); + if (IS_ERR(bd)) + return dev_err_probe(dev, PTR_ERR(bd), + "failed to register backlight"); + + bd->props.max_brightness = max_brightness; + bd->props.brightness = brightness; + + ktd2801->bd = bd; + platform_set_drvdata(pdev, bd); + backlight_update_status(bd); + + return 0; +} + +static const struct of_device_id ktd2801_of_match[] = { + { .compatible = "kinetic,ktd2801" }, + { } +}; +MODULE_DEVICE_TABLE(of, ktd2801_of_match); + +static struct platform_driver ktd2801_backlight_driver = { + .driver = { + .name = "ktd2801-backlight", + .of_match_table = ktd2801_of_match, + }, + .probe = ktd2801_backlight_probe, +}; +module_platform_driver(ktd2801_backlight_driver); + +MODULE_IMPORT_NS(EXPRESSWIRE); +MODULE_AUTHOR("Duje Mihanović "); +MODULE_DESCRIPTION("Kinetic KTD2801 Backlight Driver"); +MODULE_LICENSE("GPL");