From patchwork Sat Dec 12 11:10:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Linus Walleij X-Patchwork-Id: 11970099 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C450AC1B0E3 for ; Sat, 12 Dec 2020 11:11:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 93E40206C3 for ; Sat, 12 Dec 2020 11:11:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2407207AbgLLLLl (ORCPT ); Sat, 12 Dec 2020 06:11:41 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53518 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2405831AbgLLLLd (ORCPT ); Sat, 12 Dec 2020 06:11:33 -0500 Received: from mail-lf1-x144.google.com (mail-lf1-x144.google.com [IPv6:2a00:1450:4864:20::144]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 23021C0613D3 for ; Sat, 12 Dec 2020 03:10:53 -0800 (PST) Received: by mail-lf1-x144.google.com with SMTP id l11so18058260lfg.0 for ; Sat, 12 Dec 2020 03:10:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=6D+Cc+FWzkuVAMuJyIf/5H2M4c00AdBlhTqbWNSCZm0=; b=GizqmZW/nzKIZu+I34FDCPOhLvRDExiud2qtvNWshB+8md8EdQN8CqOYwHDq/AhyKi YX+gAcM1So80rzozdxNbBrL2NqprgZz5KZdu3rhkUQQD0Y/jo+IVkdiCed9f73ydUl5e 1ZiPxxgLaumyM0iTsfTmZ6I4pUjIN3DWFUwTtGe2o4IVGAHRrTImDMYvp9GysfNP+f6C Gr4QIy4y0Jt0ZGh2VYWhN0FWIuDM+RDNmbvE7oWHXrS1st8LTOqGpEznAK5EWNjXei2Y W35loXav2NFB973puS1Gj980pc6K3pLHxaPRFeYcMwyUCQAlUWGJIC4QzDmT17m1jHR+ tgMg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=6D+Cc+FWzkuVAMuJyIf/5H2M4c00AdBlhTqbWNSCZm0=; b=RJ76TbWD8e0J4xuK2ojPT5djJoGAIwZdvIP9YsYNXofinimWzINZQIWiMAlHKBHUqc WDcspnrlOGE+2dVTfpIToeBxCZkV2XhxEqCwcIDUmGnUGdyov35lDOvsgVbzw+XpHI7N i7P/9Wi7l18RnSX/EgdYJZVK8ccxNxdiT7H/szCZWDC35KyhTw25x25iauKQoWnsKI5S 0MjOeOBrTQ/LJjlG/R/yBLxUm8//eUbQQ2K8QgZZV/XBM43F9zqK0WpFkUmGJcl/0Phj BaqFW46iw6YpSZV11jAEBMEfWEgNLFzZUVcw+cSwFgVtn218yBuB1iv/SXXAtGDNBpad QljA== X-Gm-Message-State: AOAM533P6aqQpW+KRO+SkEvntaD9uBAbZRHAjaP1YJvVwA2RHDsp46R/ Plnpe6KOoqs/EloOerSUU1SP3Q== X-Google-Smtp-Source: ABdhPJyXfKgOEIjRFc92p6si3OoJuinKJU1r0rrGNBi5ah36legqEcPex6KMu7sSNuxEVjI8tEkVnw== X-Received: by 2002:ac2:5d68:: with SMTP id h8mr6059551lft.448.1607771451504; Sat, 12 Dec 2020 03:10:51 -0800 (PST) Received: from localhost.bredbandsbolaget (c-92d7225c.014-348-6c756e10.bbcust.telenor.se. [92.34.215.146]) by smtp.gmail.com with ESMTPSA id u30sm1187835lfc.238.2020.12.12.03.10.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 12 Dec 2020 03:10:50 -0800 (PST) From: Linus Walleij To: Jacek Anaszewski , Pavel Machek , Dan Murphy Cc: linux-leds@vger.kernel.org, Linus Walleij , Sakari Ailus , newbytee@protonmail.com, Stephan Gerhold , phone-devel@vger.kernel.org, linux-media@vger.kernel.org, devicetree@vger.kernel.org, Rob Herring , Sakari Ailus Subject: [PATCH 1/2 v8] dt-bindings: leds: Add DT binding for Richtek RT8515 Date: Sat, 12 Dec 2020 12:10:45 +0100 Message-Id: <20201212111046.2735002-1-linus.walleij@linaro.org> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Add a YAML devicetree binding for the Richtek RT8515 dual channel flash/torch LED driver. Cc: Sakari Ailus Cc: newbytee@protonmail.com Cc: Stephan Gerhold Cc: phone-devel@vger.kernel.org Cc: linux-media@vger.kernel.org Cc: devicetree@vger.kernel.org Reviewed-by: Rob Herring Reviewed-by: Sakari Ailus Signed-off-by: Linus Walleij --- ChangeLog v7->v8: - Add additionalProperties: fals to the leds subnode - Fix the bug in the example. - Collect Rob's Reviewed-by. ChangeLog v6->v7: - Use led-max-microamp for the torch mode max current. - Drop the torch-specific new property from common.yaml in favor of this property. - Collect Sakari's review tag. ChangeLog v5->v6: - Use the suffix -ohms for the resistor values as this gets recognized by default by dtschema and is nominal. ChangeLog v4->v5: - Fix the RFS/RTS resistors to reference the u32 schema. - Fix resisitor speling error. ChangeLog v3->v4: - Add DT attributes for the RFS and RTS resistors, so that the hardware-defined maximum current can be determined. - Add torch-max-microamp to the common bindings so we can set an attribute for the max microamp in torch mode. - Add flash-max-microamp and torch-max-microamp as optional to the LED node. - Slot in some elabortative descriptions of the new properties and describe what the hardware is doing. - Cc phone-devel@vger.kernel.org ChangeLog v2->v3: - Add Sakari to CC - Resend ChangeLog v1->v2: - Explicitly inherit function, color and flash-max-timeout-us from common.yaml - Add "led" node as required. --- .../bindings/leds/richtek,rt8515.yaml | 111 ++++++++++++++++++ 1 file changed, 111 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/richtek,rt8515.yaml diff --git a/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml new file mode 100644 index 000000000000..68c328eec03b --- /dev/null +++ b/Documentation/devicetree/bindings/leds/richtek,rt8515.yaml @@ -0,0 +1,111 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/leds/richtek,rt8515.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Richtek RT8515 1.5A dual channel LED driver + +maintainers: + - Linus Walleij + +description: | + The Richtek RT8515 is a dual channel (two mode) LED driver that + supports driving a white LED in flash or torch mode. The maximum + current for each mode is defined in hardware using two resistors + RFS and RTS. + +properties: + compatible: + const: richtek,rt8515 + + enf-gpios: + maxItems: 1 + description: A connection to the 'ENF' (enable flash) pin. + + ent-gpios: + maxItems: 1 + description: A connection to the 'ENT' (enable torch) pin. + + richtek,rfs-ohms: + minimum: 7680 + maximum: 367000 + description: The resistance value of the RFS resistor. This + resistors limits the maximum flash current. This must be set + for the property flash-max-microamp to work, the RFS resistor + defines the range of the dimmer setting (brightness) of the + flash LED. + + richtek,rts-ohms: + minimum: 7680 + maximum: 367000 + description: The resistance value of the RTS resistor. This + resistors limits the maximum torch current. This must be set + for the property torch-max-microamp to work, the RTS resistor + defines the range of the dimmer setting (brightness) of the + torch LED. + + led: + type: object + $ref: common.yaml# + properties: + function: true + color: true + flash-max-timeout-us: true + + flash-max-microamp: + maximum: 700000 + description: The maximum current for flash mode + is hardwired to the component using the RFS resistor to + ground. The maximum hardware current setting is calculated + according to the formula Imax = 5500 / RFS. The lowest + allowed resistance value is 7.86 kOhm giving an absolute + maximum current of 700mA. By setting this attribute in + the device tree, you can further restrict the maximum + current below the hardware limit. This requires the RFS + to be defined as it defines the maximum range. + + led-max-microamp: + maximum: 700000 + description: The maximum current for torch mode + is hardwired to the component using the RTS resistor to + ground. The maximum hardware current setting is calculated + according to the formula Imax = 5500 / RTS. The lowest + allowed resistance value is 7.86 kOhm giving an absolute + maximum current of 700mA. By setting this attribute in + the device tree, you can further restrict the maximum + current below the hardware limit. This requires the RTS + to be defined as it defines the maximum range. + + additionalProperties: false + +required: + - compatible + - ent-gpios + - enf-gpios + - led + +additionalProperties: false + +examples: + - | + #include + #include + + led-controller { + compatible = "richtek,rt8515"; + enf-gpios = <&gpio4 12 GPIO_ACTIVE_HIGH>; + ent-gpios = <&gpio4 13 GPIO_ACTIVE_HIGH>; + richtek,rfs-ohms = <16000>; + richtek,rts-ohms = <100000>; + + led { + function = LED_FUNCTION_FLASH; + color = ; + flash-max-timeout-us = <250000>; + flash-max-microamp = <150000>; + led-max-microamp = <25000>; + }; + }; + +... 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[92.34.215.146]) by smtp.gmail.com with ESMTPSA id u30sm1187835lfc.238.2020.12.12.03.10.52 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 12 Dec 2020 03:10:52 -0800 (PST) From: Linus Walleij To: Jacek Anaszewski , Pavel Machek , Dan Murphy Cc: linux-leds@vger.kernel.org, Linus Walleij , Sakari Ailus , newbytee@protonmail.com, Stephan Gerhold , linux-media@vger.kernel.org, phone-devel@vger.kernel.org, Sakari Ailus Subject: [PATCH 2/2 v8] leds: rt8515: Add Richtek RT8515 LED driver Date: Sat, 12 Dec 2020 12:10:46 +0100 Message-Id: <20201212111046.2735002-2-linus.walleij@linaro.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201212111046.2735002-1-linus.walleij@linaro.org> References: <20201212111046.2735002-1-linus.walleij@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org This adds a driver for the Richtek RT8515 dual channel torch/flash white LED driver. This LED driver is found in some mobile phones from Samsung such as the GT-S7710 and GT-I8190. A V4L interface is added. We do not have a proper datasheet for the RT8515 but it turns out that RT9387A has a public datasheet and is essentially the same chip. We designed the driver in accordance with this datasheet. The day someone needs to drive a RT9387A this driver can probably easily be augmented to handle that chip too. Cc: Sakari Ailus Cc: newbytee@protonmail.com Cc: Stephan Gerhold Cc: linux-media@vger.kernel.org Cc: phone-devel@vger.kernel.org Reviewed-by: Sakari Ailus Signed-off-by: Linus Walleij --- ChangeLog v7->v8: - Add comments in the top of the driver and a link to the RT9387A datasheet. ChangeLog v6->v7: - Account for the binding change to use led-max-current rather than torch-specific current. - Collect Sakari's review tag. ChangeLog v5->v6: - Use the configured max flash brightness instead of hardcoded "4". - Implement the new "-ohms" suffixes on the resistors. ChangeLog v4->v5: - Fix a missing static keyword, complaint from the kernel autobuilder robot. ChangeLog v3->v4: - Create a new subdirectory for flash LEDs under drivers/leds/flash as requested by Pavel, move the driver there and set up a kbuild structure for pure flash LEDs. (Others can follow the established pattern.) - Handle the new richtek,rfs and richtek,rts resistor values that make it possible to determine the current range configured in the hardware. - Handle the new flash-max-microamp and torch-max-microamp if present and optionally further restrict the current range using these. Otherwise fall back on the hardware defaults as specified by the RFS and RTS resistors. - Cc phone-devel@vger.kernel.org - License as GPL-2.0-or-later - Renable ent and enf gpio descriptors to enable_torch and enable_flash Changelog v2->v3: - Expand commit message. - Add Sakari to Cc. - Resend. ChangeLog v1->v2: - Break out routine to bitbang the brightness on a GPIO pin. - Do not hardcode the LED name so that the framework can name it from DT properties. --- drivers/leds/Kconfig | 3 + drivers/leds/Makefile | 3 + drivers/leds/flash/Kconfig | 15 ++ drivers/leds/flash/Makefile | 3 + drivers/leds/flash/leds-rt8515.c | 393 +++++++++++++++++++++++++++++++ 5 files changed, 417 insertions(+) create mode 100644 drivers/leds/flash/Kconfig create mode 100644 drivers/leds/flash/Makefile create mode 100644 drivers/leds/flash/leds-rt8515.c diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 849d3c5f908e..6c1d8b69a465 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -928,6 +928,9 @@ config LEDS_ACER_A500 This option enables support for the Power Button LED of Acer Iconia Tab A500. +comment "Flash and Torch LED drivers" +source "drivers/leds/flash/Kconfig" + comment "LED Triggers" source "drivers/leds/trigger/Kconfig" diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 73e603e1727e..156c0b4e60d9 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -103,5 +103,8 @@ obj-$(CONFIG_LEDS_SPI_BYTE) += leds-spi-byte.o # LED Userspace Drivers obj-$(CONFIG_LEDS_USER) += uleds.o +# Flash and Torch LED Drivers +obj-$(CONFIG_LEDS_CLASS_FLASH) += flash/ + # LED Triggers obj-$(CONFIG_LEDS_TRIGGERS) += trigger/ diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig new file mode 100644 index 000000000000..d21d273ef3da --- /dev/null +++ b/drivers/leds/flash/Kconfig @@ -0,0 +1,15 @@ +# SPDX-License-Identifier: GPL-2.0 + +if LEDS_CLASS_FLASH + +config LEDS_RT8515 + tristate "LED support for Richtek RT8515 flash/torch LED" + depends on GPIOLIB + help + This option enables support for the Richtek RT8515 flash + and torch LEDs found on some mobile phones. + + To compile this driver as a module, choose M here: the module + will be called leds-rt8515. + +endif # LEDS_CLASS_FLASH diff --git a/drivers/leds/flash/Makefile b/drivers/leds/flash/Makefile new file mode 100644 index 000000000000..e990e257f4d7 --- /dev/null +++ b/drivers/leds/flash/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_LEDS_RT8515) += leds-rt8515.o diff --git a/drivers/leds/flash/leds-rt8515.c b/drivers/leds/flash/leds-rt8515.c new file mode 100644 index 000000000000..571aec521619 --- /dev/null +++ b/drivers/leds/flash/leds-rt8515.c @@ -0,0 +1,393 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * LED driver for Richtek RT8515 flash/torch white LEDs + * found on some Samsung mobile phones. + * + * This is a 1.5A Boost dual channel driver produced around 2011. + * + * The component lacks a datasheet, but in the schematic picture + * from the LG P970 service manual you can see the connections + * from the RT8515 to the LED, with two resistors connected + * from the pins "RFS" and "RTS" to ground. + * + * On the LG P970: + * RFS (resistance flash setting?) is 20 kOhm + * RTS (resistance torch setting?) is 39 kOhm + * + * Some sleuthing finds us the RT9387A which we have a datasheet for: + * https://static5.arrow.com/pdfs/2014/7/27/8/21/12/794/rtt_/manual/94download_ds.jspprt9387a.jspprt9387a.pdf + * This apparently works the same way so in theory this driver + * should cover RT9387A as well. This has not been tested, please + * update the compatibles if you add RT9387A support. + * + * Linus Walleij + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +/* We can provide 15-700 mA out to the LED */ +#define RT8515_MIN_IOUT_MA 15 +#define RT8515_MAX_IOUT_MA 700 +/* The maximum intensity is 1-16 for flash and 1-100 for torch */ +#define RT8515_FLASH_MAX 16 +#define RT8515_TORCH_MAX 100 + +#define RT8515_TIMEOUT_DEFAULT 250000U /* 250ms */ +#define RT8515_MAX_TIMEOUT_DEFAULT 300000U /* 300ms */ + +struct rt8515 { + struct device *dev; + struct led_classdev_flash fled; + struct v4l2_flash *v4l2_flash; + struct mutex lock; + struct regulator *reg; + struct gpio_desc *enable_torch; + struct gpio_desc *enable_flash; + struct timer_list powerdown_timer; + u32 max_timeout; /* Flash max timeout */ + int flash_max_intensity; + int torch_max_intensity; +}; + +static struct rt8515 *to_rt8515(struct led_classdev_flash *fled) +{ + return container_of(fled, struct rt8515, fled); +} + +static void rt8515_gpio_brightness_commit(struct gpio_desc *gpiod, + int brightness) +{ + int i; + + /* + * Toggling a GPIO line with a small delay increases the + * brightness one step at a time. + */ + for (i = 0; i < brightness; i++) { + gpiod_set_value(gpiod, 0); + udelay(1); + gpiod_set_value(gpiod, 1); + udelay(1); + } +} + +/* This is setting the torch light level */ +static int rt8515_led_brightness_set(struct led_classdev *led, + enum led_brightness brightness) +{ + struct led_classdev_flash *fled = lcdev_to_flcdev(led); + struct rt8515 *rt = to_rt8515(fled); + + mutex_lock(&rt->lock); + + if (brightness == LED_OFF) { + /* Off */ + gpiod_set_value(rt->enable_flash, 0); + gpiod_set_value(rt->enable_torch, 0); + } else if (brightness < RT8515_TORCH_MAX) { + /* Step it up to movie mode brightness using the flash pin */ + rt8515_gpio_brightness_commit(rt->enable_torch, brightness); + } else { + /* Max torch brightness requested */ + gpiod_set_value(rt->enable_torch, 1); + } + + mutex_unlock(&rt->lock); + + return 0; +} + +static int rt8515_led_flash_strobe_set(struct led_classdev_flash *fled, + bool state) +{ + struct rt8515 *rt = to_rt8515(fled); + struct led_flash_setting *timeout = &fled->timeout; + int brightness = rt->flash_max_intensity; + + mutex_lock(&rt->lock); + + if (state) { + /* Enable LED flash mode and set brightness */ + rt8515_gpio_brightness_commit(rt->enable_flash, brightness); + /* Set timeout */ + mod_timer(&rt->powerdown_timer, + jiffies + usecs_to_jiffies(timeout->val)); + } else { + del_timer_sync(&rt->powerdown_timer); + /* Turn the LED off */ + gpiod_set_value(rt->enable_flash, 0); + gpiod_set_value(rt->enable_torch, 0); + } + + fled->led_cdev.brightness = LED_OFF; + /* After this the torch LED will be disabled */ + + mutex_unlock(&rt->lock); + + return 0; +} + +static int rt8515_led_flash_strobe_get(struct led_classdev_flash *fled, + bool *state) +{ + struct rt8515 *rt = to_rt8515(fled); + + *state = timer_pending(&rt->powerdown_timer); + + return 0; +} + +static int rt8515_led_flash_timeout_set(struct led_classdev_flash *fled, + u32 timeout) +{ + /* The timeout is stored in the led-class-flash core */ + return 0; +} + +static const struct led_flash_ops rt8515_flash_ops = { + .strobe_set = rt8515_led_flash_strobe_set, + .strobe_get = rt8515_led_flash_strobe_get, + .timeout_set = rt8515_led_flash_timeout_set, +}; + +static void rt8515_powerdown_timer(struct timer_list *t) +{ + struct rt8515 *rt = from_timer(rt, t, powerdown_timer); + + /* Turn the LED off */ + gpiod_set_value(rt->enable_flash, 0); + gpiod_set_value(rt->enable_torch, 0); +} + +static void rt8515_init_flash_timeout(struct rt8515 *rt) +{ + struct led_classdev_flash *fled = &rt->fled; + struct led_flash_setting *s; + + /* Init flash timeout setting */ + s = &fled->timeout; + s->min = 1; + s->max = rt->max_timeout; + s->step = 1; + /* + * Set default timeout to RT8515_DEFAULT_TIMEOUT except if + * max_timeout from DT is lower. + */ + s->val = min(rt->max_timeout, RT8515_TIMEOUT_DEFAULT); +} + +#if IS_ENABLED(CONFIG_V4L2_FLASH_LED_CLASS) +/* Configure the V2L2 flash subdevice */ +static void rt8515_init_v4l2_flash_config(struct rt8515 *rt, + struct v4l2_flash_config *v4l2_sd_cfg) +{ + struct led_classdev *led = &rt->fled.led_cdev; + struct led_flash_setting *s; + + strscpy(v4l2_sd_cfg->dev_name, led->dev->kobj.name, + sizeof(v4l2_sd_cfg->dev_name)); + + /* + * Init flash intensity setting: this is a linear scale + * capped from the device tree max intensity setting + * 1..flash_max_intensity + */ + s = &v4l2_sd_cfg->intensity; + s->min = 1; + s->max = rt->flash_max_intensity; + s->step = 1; + s->val = s->max; +} + +#else +static void rt8515_init_v4l2_flash_config(struct rt8515 *rt, + struct v4l2_flash_config *v4l2_sd_cfg) +{ +} +#endif + +static void rt8515_determine_max_intensity(struct rt8515 *rt, + struct fwnode_handle *led, + const char *resistance, + const char *max_ua_prop, int hw_max, + int *max_intensity_setting) +{ + u32 res; + u32 ua; + u32 max_ma; + int max_intensity; + int ret1, ret2; + + + ret1 = fwnode_property_read_u32(rt->dev->fwnode, resistance, &res); + ret2 = fwnode_property_read_u32(led, max_ua_prop, &ua); + + /* No info in DT, OK go with hardware maxima */ + if (ret1 && ret2) { + max_ma = RT8515_MAX_IOUT_MA; + max_intensity = hw_max; + goto out_assign_max; + } + + if (ret1 || ret2) { + dev_err(rt->dev, + "either %s or %s missing from DT, using HW max\n", + resistance, max_ua_prop); + max_ma = RT8515_MAX_IOUT_MA; + max_intensity = hw_max; + goto out_assign_max; + } + + /* + * Formula from datasheet, this is the maximum current + * defined by the hardware. + */ + max_ma = (5500 * 1000) / res; + /* + * Calculate max intensity (linear scaling) + * Formula is ((ua / 1000) / max_ma) * 100, then simplified + */ + max_intensity = (ua / 10) / max_ma; + + dev_info(rt->dev, + "current restricted from %u to %u mA, max intensity %d/100\n", + max_ma, (ua / 1000), max_intensity); + +out_assign_max: + dev_info(rt->dev, "max intensity %d/%d = %d mA\n", + max_intensity, hw_max, max_ma); + *max_intensity_setting = max_intensity; +} + +static int rt8515_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct fwnode_handle *child; + struct rt8515 *rt; + struct led_classdev *led; + struct led_classdev_flash *fled; + struct led_init_data init_data = {}; + struct v4l2_flash_config v4l2_sd_cfg = {}; + int ret; + + rt = devm_kzalloc(dev, sizeof(*rt), GFP_KERNEL); + if (!rt) + return -ENOMEM; + + rt->dev = dev; + fled = &rt->fled; + led = &fled->led_cdev; + + /* ENF - Enable Flash line */ + rt->enable_flash = devm_gpiod_get(dev, "enf", GPIOD_OUT_LOW); + if (IS_ERR(rt->enable_flash)) { + dev_err(dev, "cannot get ENF (enable flash) GPIO\n"); + return PTR_ERR(rt->enable_flash); + } + + /* ENT - Enable Torch line */ + rt->enable_torch = devm_gpiod_get(dev, "ent", GPIOD_OUT_LOW); + if (IS_ERR(rt->enable_torch)) { + dev_err(dev, "cannot get ENT (enable torch) GPIO\n"); + return PTR_ERR(rt->enable_torch); + } + + child = fwnode_get_next_available_child_node(dev->fwnode, NULL); + if (!child) { + dev_err(dev, + "No fwnode child node found for connected LED.\n"); + return -EINVAL; + } + init_data.fwnode = child; + + rt8515_determine_max_intensity(rt, child, "richtek,rfs-ohms", + "flash-max-microamp", + RT8515_FLASH_MAX, + &rt->flash_max_intensity); + rt8515_determine_max_intensity(rt, child, "richtek,rts-ohms", + "led-max-microamp", + RT8515_TORCH_MAX, + &rt->torch_max_intensity); + + ret = fwnode_property_read_u32(child, "flash-max-timeout-us", + &rt->max_timeout); + if (ret) { + rt->max_timeout = RT8515_MAX_TIMEOUT_DEFAULT; + dev_warn(dev, + "flash-max-timeout-us property missing\n"); + } + timer_setup(&rt->powerdown_timer, rt8515_powerdown_timer, 0); + rt8515_init_flash_timeout(rt); + + fled->ops = &rt8515_flash_ops; + + led->max_brightness = rt->torch_max_intensity; + led->brightness_set_blocking = rt8515_led_brightness_set; + led->flags |= LED_CORE_SUSPENDRESUME | LED_DEV_CAP_FLASH; + + mutex_init(&rt->lock); + + platform_set_drvdata(pdev, rt); + + ret = devm_led_classdev_flash_register_ext(dev, fled, &init_data); + if (ret) { + dev_err(dev, "can't register LED %s\n", led->name); + mutex_destroy(&rt->lock); + return ret; + } + + rt8515_init_v4l2_flash_config(rt, &v4l2_sd_cfg); + + /* Create a V4L2 Flash device if V4L2 flash is enabled */ + rt->v4l2_flash = v4l2_flash_init(dev, child, fled, NULL, &v4l2_sd_cfg); + if (IS_ERR(rt->v4l2_flash)) { + ret = PTR_ERR(rt->v4l2_flash); + dev_err(dev, "failed to register V4L2 flash device (%d)\n", + ret); + /* + * Continue without the V4L2 flash + * (we still have the classdev) + */ + } + + return 0; +} + +static int rt8515_remove(struct platform_device *pdev) +{ + struct rt8515 *rt = platform_get_drvdata(pdev); + + v4l2_flash_release(rt->v4l2_flash); + del_timer_sync(&rt->powerdown_timer); + mutex_destroy(&rt->lock); + + return 0; +} + +static const struct of_device_id rt8515_match[] = { + { .compatible = "richtek,rt8515", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, rt8515_match); + +static struct platform_driver rt8515_driver = { + .driver = { + .name = "rt8515", + .of_match_table = rt8515_match, + }, + .probe = rt8515_probe, + .remove = rt8515_remove, +}; +module_platform_driver(rt8515_driver); + +MODULE_AUTHOR("Linus Walleij "); +MODULE_DESCRIPTION("Richtek RT8515 LED driver"); +MODULE_LICENSE("GPL v2");