From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753501AbbJPGJZ (ORCPT ); Fri, 16 Oct 2015 02:09:25 -0400 Received: from mailout2.samsung.com ([203.254.224.25]:59661 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752172AbbJPGJV (ORCPT ); Fri, 16 Oct 2015 02:09:21 -0400 MIME-version: 1.0 Content-type: text/plain; charset=utf-8 X-AuditID: cbfee691-f79d66d000001509-6b-5620948fe42b Content-transfer-encoding: 8BIT Message-id: <5620948F.8000303@samsung.com> Date: Fri, 16 Oct 2015 15:09:19 +0900 From: Ingi Kim User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 To: Jacek Anaszewski Cc: robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, sameo@linux.intel.com, lee.jones@linaro.org, rpurdie@rpsys.net, inki.dae@samsung.com, sw0312.kim@samsung.com, beomho.seo@samsung.com, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-leds@vger.kernel.org Subject: Re: [PATCH v2 3/3] leds: rt5033: Add RT5033 Flash led device driver References: <1444655578-19806-1-git-send-email-ingi2.kim@samsung.com> <1444655578-19806-4-git-send-email-ingi2.kim@samsung.com> <561BCD71.9020001@samsung.com> <561C7354.9080504@samsung.com> <561CC67E.6050107@samsung.com> In-reply-to: <561CC67E.6050107@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFrrJIsWRmVeSWpSXmKPExsWyRsSkQLd/ikKYwcWPShanP21jt5h/5Byr Rf+bhawW516tZLSYdH8Ci0Xv1eeMFve/HmW0uLxrDpvF1jfrGC2WXr/IZDFh+loWi9a9R9gt du96ympxupvVYsbkl2wO/B5r5q1h9Ljc18vksXL5FzaPTas62TzuXNvD5jHvZKDHnvk/WD36 tqxi9Pi8SS6AM4rLJiU1J7MstUjfLoEro/vWVpaCZrOKPTMvMjUwbtLqYuTkkBAwkdh1upkF whaTuHBvPVsXIxeHkMAKRonObd3MXYwcYEX37nBAxJcySmzdsZkVpIFXQFDix+R7LCA1zALy EkcuZUOY6hJTpuSCVAgJPGCUONIUBVGtJdHWeIYJxGYRUJX4duwoG4jNJqAmcWPFQrC4qECC xPGzP8BsEQF9iYaGPkaQtcwCN5kkvv5uAWsQFvCReNb5mwliwSNGiTXN0SA2p4C2xIH2RSwg DRICSzkkpj7tYIXYJiDxbfIhFohfZCU2HWCG+FdS4uCKGywTGMVmIflmFsI3sxC+WcDIvIpR NLUguaA4Kb3IVK84Mbe4NC9dLzk/dxMjMMZP/3s2cQfj/QPWhxgFOBiVeHgZ7BTChFgTy4or cw8xmgLdMJFZSjQ5H5hI8kriDY3NjCxMTUyNjcwtzZTEeXWkfwYLCaQnlqRmp6YWpBbFF5Xm pBYfYmTi4JRqYDRj2ZR974DmiWnZ3Euj+GfbnlRy0J2U8sjKeG7pEbYn3o83m1U/9ksqqNB6 suFPe8P38tdvvcQ49i56tjb3R9N+K45rqh/usb2cFird929Pds42m+s5mb+lrXLX79GeO1uD 5a30q9tnTk232Xyh5E/JTenGIt6T82O7FxoKvLqqNuPZvx/HE+YpsRRnJBpqMRcVJwIAzITY HuwCAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrGKsWRmVeSWpSXmKPExsVy+t9jAd3+KQphBh8mS1uc/rSN3WL+kXOs Fv1vFrJanHu1ktFi0v0JLBa9V58zWtz/epTR4vKuOWwWW9+sY7RYev0ik8WE6WtZLFr3HmG3 2L3rKavF6W5WixmTX7I58HusmbeG0eNyXy+Tx8rlX9g8Nq3qZPO4c20Pm8e8k4Eee+b/YPXo 27KK0ePzJrkAzqgGRpuM1MSU1CKF1Lzk/JTMvHRbJe/geOd4UzMDQ11DSwtzJYW8xNxUWyUX nwBdt8wcoA+UFMoSc0qBQgGJxcVK+naYJoSGuOlawDRG6PqGBMH1GBmggYQ1jBndt7ayFDSb VeyZeZGpgXGTVhcjB4eEgInEvTscXYycQKaYxIV769m6GLk4hASWMkps3bGZFSTBKyAo8WPy PRaQemYBeYkjl7IhTHWJKVNyQSqEBB4wShxpioKo1pJoazzDBGKzCKhKfDt2lA3EZhNQk7ix YiFYXFQgQeL42R9gtoiAvkRDQx8jyFpmgZtMEl9/t4A1CAv4SDzr/M0EseARo8Sa5mgQm1NA W+JA+yKWCYwCs5BcNwvhulkI1y1gZF7FKJFakFxQnJSea5SXWq5XnJhbXJqXrpecn7uJEZxG nknvYDy8y/0QowAHoxIPL6OdQpgQa2JZcWXuIUYJDmYlEd6uGKAQb0piZVVqUX58UWlOavEh RlOg/yYyS4km5wNTXF5JvKGxiZmRpZG5oYWRsbmSOO+NQwxhQgLpiSWp2ampBalFMH1MHJxS DYwLY9UYEuacP/jXeE8Ap6CQ+t1K1hAlxcPNgUyyf8xe9TbH1JedPjJdQmdHjHDjh4Y15h/r PT5kcnW8eM7Tdfp2crzxXDdPW609kpEzYv498lu82V36xmrO8otZ29P4lnWeE1/ndyHUprIu SNfTvlK4n7376XSnRPbVok4mZ0qvNf0Pe3hAUYmlOCPRUIu5qDgRAMqj4d85AwAA DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Jacek, Sorry I'm late :( I'll send version3 patch soon On 2015년 10월 13일 17:53, Jacek Anaszewski wrote: > Hi Ingi, > > On 10/13/2015 04:58 AM, Ingi Kim wrote: >> Hi Jacek, >> >> Thanks for your kind comments >> I also append reply below >> >> On 2015년 10월 13일 00:10, Jacek Anaszewski wrote: >>> Hi Ingi, >>> >>> Thanks for the update. Few comments below. >>> >>> On 10/12/2015 03:12 PM, Ingi Kim wrote: >>>> This patch adds device driver of Richtek RT5033 PMIC. >>>> The driver supports a current regulated output to drive >>>> white LEDs for camera flash. >>>> >>>> Signed-off-by: Ingi Kim >>>> --- >>>> drivers/leds/Kconfig | 8 ++ >>>> drivers/leds/Makefile | 1 + >>>> drivers/leds/leds-rt5033.c | 223 +++++++++++++++++++++++++++++++++++++ >>>> include/linux/mfd/rt5033-private.h | 49 ++++++++ >>>> include/linux/mfd/rt5033.h | 22 +++- >>>> 5 files changed, 301 insertions(+), 2 deletions(-) >>>> create mode 100644 drivers/leds/leds-rt5033.c >>>> >>>> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig >>>> index 42990f2..29613e3 100644 >>>> --- a/drivers/leds/Kconfig >>>> +++ b/drivers/leds/Kconfig >>>> @@ -345,6 +345,14 @@ config LEDS_PCA963X >>>> LED driver chip accessed via the I2C bus. Supported >>>> devices include PCA9633 and PCA9634 >>>> >>>> +config LEDS_RT5033 >>>> + tristate "LED support for RT5033 PMIC" >>>> + depends on LEDS_CLASS_FLASH && OF >>>> + depends on MFD_RT5033 >>>> + help >>>> + This option enables support for on-chip LED driver on >>>> + RT5033 PMIC. >>>> + >>>> config LEDS_WM831X_STATUS >>>> tristate "LED support for status LEDs on WM831x PMICs" >>>> depends on LEDS_CLASS >>>> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile >>>> index b503f92..bcc4d93 100644 >>>> --- a/drivers/leds/Makefile >>>> +++ b/drivers/leds/Makefile >>>> @@ -23,6 +23,7 @@ obj-$(CONFIG_LEDS_COBALT_QUBE) += leds-cobalt-qube.o >>>> obj-$(CONFIG_LEDS_COBALT_RAQ) += leds-cobalt-raq.o >>>> obj-$(CONFIG_LEDS_SUNFIRE) += leds-sunfire.o >>>> obj-$(CONFIG_LEDS_PCA9532) += leds-pca9532.o >>>> +obj-$(CONFIG_LEDS_RT5033) += leds-rt5033.o >>>> obj-$(CONFIG_LEDS_GPIO_REGISTER) += leds-gpio-register.o >>>> obj-$(CONFIG_LEDS_GPIO) += leds-gpio.o >>>> obj-$(CONFIG_LEDS_LP3944) += leds-lp3944.o >>>> diff --git a/drivers/leds/leds-rt5033.c b/drivers/leds/leds-rt5033.c >>>> new file mode 100644 >>>> index 0000000..b470c94 >>>> --- /dev/null >>>> +++ b/drivers/leds/leds-rt5033.c >>>> @@ -0,0 +1,223 @@ >>>> +/* >>>> + * led driver for RT5033 >>>> + * >>>> + * Copyright (C) 2015 Samsung Electronics, Co., Ltd. >>>> + * Ingi Kim >>>> + * >>>> + * This program is free software; you can redistribute it and/or modify >>>> + * it under the terms of the GNU General Public License version 2 as >>>> + * published by the Free Software Foundation. >>>> + * >>>> + */ >>>> + >>>> +#include >>>> +#include >>>> +#include >>>> +#include >>>> + >>>> +#define RT5033_LED_FLASH_TIMEOUT_MIN 64000 >>>> +#define RT5033_LED_FLASH_TIMEOUT_STEPS 32000 >>>> +#define RT5033_LED_TORCH_CURRENT_LEVEL_MAX 16 >>>> + >>>> +/* Macro for getting offset of flash timeout */ >>>> +#define GET_TIMEOUT_OFFSET(tm, step) ((tm) / (step) - 2) >>>> + >>>> +static struct rt5033_led *flcdev_to_led( >>>> + struct led_classdev_flash *fled_cdev) >>>> +{ >>>> + return container_of(fled_cdev, struct rt5033_led, fled_cdev); >>>> +} >>>> + >>>> +static int rt5033_led_brightness_set(struct led_classdev *led_cdev, >>>> + enum led_brightness brightness) >>>> +{ >>>> + struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(led_cdev); >>>> + struct rt5033_led *led = flcdev_to_led(fled_cdev); >>> >>> I assume that you don't use mutex here deliberately? >>> >> >> Actually I'm not sure why flash driver uses mutex. > > Which flash driver do you have on mind? > Oh, nothing on my mind, I can understand it's usage on flash led driver through your description >> In consideration of blocking competition, however, I'd be better to use it >> > > [...] > >>>> + >>>> +static int rt5033_led_flash_strobe_set(struct led_classdev_flash *fled_cdev, >>>> + bool state) >>>> +{ >>>> + struct rt5033_led *led = flcdev_to_led(fled_cdev); >>>> + u32 flash_tm_reg; >>> >>> I think that you need a mutex here and in rt5033_led_flash_strobe_set. Otherwise following is possible: >>> >>> Process 1: >>> rt5033_led_flash_strobe_set(led_cdev, 1); >>> >>> regmap_update_bits(led->regmap, RT5033_REG_FLED_FUNCTION1, >>> RT5033_FLED_FUNC1_MASK, RT5033_FLED_RESET); >>> fled_cdev->led_cdev.brightness = LED_OFF; >>> >>> Process 2: >>> led_set_brightness(led_cdev, 1); >>> >>> fled_cdev->led_cdev.brightness = 1; >>> >>> rt5033_led_brightness_set(led_cdev, LED_FULL); >>> >>> regmap_update_bits(led->regmap, RT5033_REG_FLED_FUNCTION1, >>> RT5033_FLED_FUNC1_MASK, RT5033_FLED_PINCTRL); >>> regmap_update_bits(led->regmap, RT5033_REG_FLED_CTRL1, >>> RT5033_FLED_CTRL1_MASK, >>> (brightness - 1) << 4); >>> regmap_update_bits(led->regmap, RT5033_REG_FLED_FUNCTION2, >>> RT5033_FLED_CTRL2_MASK, RT5033_FLED_ENFLED); >>> >>> Process 1: >>> regmap_update_bits(led->regmap, RT5033_REG_FLED_STROBE_CTRL2, >>> RT5033_FLED_STRBCTRL2_MASK, flash_tm_reg); >>> regmap_update_bits(led->regmap, RT5033_REG_FLED_FUNCTION1, >>> RT5033_FLED_FUNC1_MASK, RT5033_FLED_STRB_SEL >>> | RT5033_FLED_PINCTRL); >>> regmap_update_bits(led->regmap, RT5033_REG_FLED_FUNCTION2, >>> RT5033_FLED_FUNC2_MASK, RT5033_FLED_ENFLED >>> >>> In a result LED class device will report brightness value 1, >>> whereas it would be inconsistent with hardware state, since >>> flash strobe turns torch mode off. >>> >>> >> >> Thanks for your explanation in detail, >> I was worried about cases of using shared resource for flash led. >> because I thought flash led would be called just from camera or directly itself. >> I should consider using mutex > > You don't provide support for v4l2-flash-led-class and you don't > implement external_strobe_set op. Only if the op is implemented a v4l2 > device can switch the strobe source from software to external, > which allows strobing the flash directly by camera sensor or ISP, > but without software interaction. > Okay, thanks :)