From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Date: Mon, 09 Mar 2015 09:40:28 +0000 Subject: Re: [PATCH v11 2/6] backlight: Add support Skyworks SKY81452 backlight driver Message-Id: <20150309094028.GM3427@x1> List-Id: References: <1425019346-4559-1-git-send-email-jack.yoo@skyworksinc.com> <1425019346-4559-3-git-send-email-jack.yoo@skyworksinc.com> In-Reply-To: <1425019346-4559-3-git-send-email-jack.yoo@skyworksinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: quoted-printable To: gyungoh@gmail.com Cc: sameo@linux.intel.com, robh+dt@kernel.org, jg1.han@samsung.com, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, trivial@kernel.org, broonie@kernel.org, florian.vaussard@epfl.ch, andrew@lunn.ch, antonynpavlov@gmail.com, hytszk@gmail.com, plagnioj@jcrosoft.com, tomi.valkeinen@ti.com, jack.yoo@skyworksinc.com, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, treding@nvidia.com, p.zabel@pengutronix.de, arno@natisbad.org, kuninori.morimoto.gx@renesas.com Applied, thanks. On Fri, 27 Feb 2015, gyungoh@gmail.com wrote: > From: Gyungoh Yoo >=20 > Signed-off-by: Gyungoh Yoo > Acked-by: Jingoo Han > Acked-by: Bryan Wu > --- > Changes v11: > Renamed 'skyworks,en-channels' property to led-sources. >=20 > Changes v10: > Removed trivial get_brightness implementations >=20 > Changes v9: > Nothing >=20 > Changes v8: > Renamed property names for backlight with vendor prefix > Modified gpio-enable property to generic property for GPIO >=20 > Changes v7: > Modified licensing text to GPLv2 >=20 > Changes v6: > Added new line character at the end of line of dev_err() >=20 > Changes v5: > Move sky81452-backlight.h to include/linux/platform_data >=20 > Changes v4: > Reordering header files for readability > Removed calling to backlight_device_unregister() > Removed MODULE_VERSION() > Modified license to GPLv2 >=20 > Changes v3: > Modified DBG messages >=20 > Changes v2: > Added 'compatible' attribute in the driver > Added message for exception or errors >=20 > drivers/video/backlight/Kconfig | 10 + > drivers/video/backlight/Makefile | 1 + > drivers/video/backlight/sky81452-backlight.c | 353 +++++++++++++++++= ++++++ > include/linux/platform_data/sky81452-backlight.h | 46 +++ > 4 files changed, 410 insertions(+) > create mode 100644 drivers/video/backlight/sky81452-backlight.c > create mode 100644 include/linux/platform_data/sky81452-backlight.h >=20 > diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kc= onfig > index efb0904..2d9923a 100644 > --- a/drivers/video/backlight/Kconfig > +++ b/drivers/video/backlight/Kconfig > @@ -408,6 +408,16 @@ config BACKLIGHT_PANDORA > If you have a Pandora console, say Y to enable the > backlight driver. > =20 > +config BACKLIGHT_SKY81452 > + tristate "Backlight driver for SKY81452" > + depends on BACKLIGHT_CLASS_DEVICE && MFD_SKY81452 > + help > + If you have a Skyworks SKY81452, say Y to enable the > + backlight driver. > + > + To compile this driver as a module, choose M here: the module will > + be called sky81452-backlight > + > config BACKLIGHT_TPS65217 > tristate "TPS65217 Backlight" > depends on BACKLIGHT_CLASS_DEVICE && MFD_TPS65217 > diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/M= akefile > index fcd50b73..d67073f 100644 > --- a/drivers/video/backlight/Makefile > +++ b/drivers/video/backlight/Makefile > @@ -50,6 +50,7 @@ obj-$(CONFIG_BACKLIGHT_PANDORA) +=3D pandora_bl.o > obj-$(CONFIG_BACKLIGHT_PCF50633) +=3D pcf50633-backlight.o > obj-$(CONFIG_BACKLIGHT_PWM) +=3D pwm_bl.o > obj-$(CONFIG_BACKLIGHT_SAHARA) +=3D kb3886_bl.o > +obj-$(CONFIG_BACKLIGHT_SKY81452) +=3D sky81452-backlight.o > obj-$(CONFIG_BACKLIGHT_TOSA) +=3D tosa_bl.o > obj-$(CONFIG_BACKLIGHT_TPS65217) +=3D tps65217_bl.o > obj-$(CONFIG_BACKLIGHT_WM831X) +=3D wm831x_bl.o > diff --git a/drivers/video/backlight/sky81452-backlight.c b/drivers/video= /backlight/sky81452-backlight.c > new file mode 100644 > index 0000000..052fa1b > --- /dev/null > +++ b/drivers/video/backlight/sky81452-backlight.c > @@ -0,0 +1,353 @@ > +/* > + * sky81452-backlight.c SKY81452 backlight driver > + * > + * Copyright 2014 Skyworks Solutions Inc. > + * Author : Gyungoh Yoo > + * > + * 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. > + * > + * This program is distributed in the hope that it will be useful, but > + * WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License alo= ng > + * with this program; if not, see . > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +/* registers */ > +#define SKY81452_REG0 0x00 > +#define SKY81452_REG1 0x01 > +#define SKY81452_REG2 0x02 > +#define SKY81452_REG4 0x04 > +#define SKY81452_REG5 0x05 > + > +/* bit mask */ > +#define SKY81452_CS 0xFF > +#define SKY81452_EN 0x3F > +#define SKY81452_IGPW 0x20 > +#define SKY81452_PWMMD 0x10 > +#define SKY81452_PHASE 0x08 > +#define SKY81452_ILIM 0x04 > +#define SKY81452_VSHRT 0x03 > +#define SKY81452_OCP 0x80 > +#define SKY81452_OTMP 0x40 > +#define SKY81452_SHRT 0x3F > +#define SKY81452_OPN 0x3F > + > +#define SKY81452_DEFAULT_NAME "lcd-backlight" > +#define SKY81452_MAX_BRIGHTNESS (SKY81452_CS + 1) > + > +#define CTZ(b) __builtin_ctz(b) > + > +static int sky81452_bl_update_status(struct backlight_device *bd) > +{ > + const struct sky81452_bl_platform_data *pdata > + dev_get_platdata(bd= ->dev.parent); > + const unsigned int brightness =3D (unsigned int)bd->props.brightness; > + struct regmap *regmap =3D bl_get_data(bd); > + int ret; > + > + if (brightness > 0) { > + ret =3D regmap_write(regmap, SKY81452_REG0, brightness - 1); > + if (IS_ERR_VALUE(ret)) > + return ret; > + > + return regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN, > + pdata->enable << CTZ(SKY81452_EN)); > + } > + > + return regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN, 0); > +} > + > +static const struct backlight_ops sky81452_bl_ops =3D { > + .update_status =3D sky81452_bl_update_status, > +}; > + > +static ssize_t sky81452_bl_store_enable(struct device *dev, > + struct device_attribute *attr, const char *buf, size_t count) > +{ > + struct regmap *regmap =3D bl_get_data(to_backlight_device(dev)); > + unsigned long value; > + int ret; > + > + ret =3D kstrtoul(buf, 16, &value); > + if (IS_ERR_VALUE(ret)) > + return ret; > + > + ret =3D regmap_update_bits(regmap, SKY81452_REG1, SKY81452_EN, > + value << CTZ(SKY81452_EN)); > + if (IS_ERR_VALUE(ret)) > + return ret; > + > + return count; > +} > + > +static ssize_t sky81452_bl_show_open_short(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct regmap *regmap =3D bl_get_data(to_backlight_device(dev)); > + unsigned int reg, value =3D 0; > + char tmp[3]; > + int i, ret; > + > + reg =3D !strcmp(attr->attr.name, "open") ? SKY81452_REG5 : SKY81452_REG= 4; > + ret =3D regmap_read(regmap, reg, &value); > + if (IS_ERR_VALUE(ret)) > + return ret; > + > + if (value & SKY81452_SHRT) { > + *buf =3D 0; > + for (i =3D 0; i < 6; i++) { > + if (value & 0x01) { > + sprintf(tmp, "%d ", i + 1); > + strcat(buf, tmp); > + } > + value >>=3D 1; > + } > + strcat(buf, "\n"); > + } else { > + strcpy(buf, "none\n"); > + } > + > + return strlen(buf); > +} > + > +static ssize_t sky81452_bl_show_fault(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + struct regmap *regmap =3D bl_get_data(to_backlight_device(dev)); > + unsigned int value =3D 0; > + int ret; > + > + ret =3D regmap_read(regmap, SKY81452_REG4, &value); > + if (IS_ERR_VALUE(ret)) > + return ret; > + > + *buf =3D 0; > + > + if (value & SKY81452_OCP) > + strcat(buf, "over-current "); > + > + if (value & SKY81452_OTMP) > + strcat(buf, "over-temperature"); > + > + strcat(buf, "\n"); > + return strlen(buf); > +} > + > +static DEVICE_ATTR(enable, S_IWGRP | S_IWUSR, NULL, sky81452_bl_store_en= able); > +static DEVICE_ATTR(open, S_IRUGO, sky81452_bl_show_open_short, NULL); > +static DEVICE_ATTR(short, S_IRUGO, sky81452_bl_show_open_short, NULL); > +static DEVICE_ATTR(fault, S_IRUGO, sky81452_bl_show_fault, NULL); > + > +static struct attribute *sky81452_bl_attribute[] =3D { > + &dev_attr_enable.attr, > + &dev_attr_open.attr, > + &dev_attr_short.attr, > + &dev_attr_fault.attr, > + NULL > +}; > + > +static const struct attribute_group sky81452_bl_attr_group =3D { > + .attrs =3D sky81452_bl_attribute, > +}; > + > +#ifdef CONFIG_OF > +static struct sky81452_bl_platform_data *sky81452_bl_parse_dt( > + struct device *dev) > +{ > + struct device_node *np =3D of_node_get(dev->of_node); > + struct sky81452_bl_platform_data *pdata; > + int num_entry; > + unsigned int sources[6]; > + int ret; > + > + if (!np) { > + dev_err(dev, "backlight node not found.\n"); > + return ERR_PTR(-ENODATA); > + } > + > + pdata =3D devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); > + if (!pdata) { > + of_node_put(np); > + return ERR_PTR(-ENOMEM); > + } > + > + of_property_read_string(np, "name", &pdata->name); > + pdata->ignore_pwm =3D of_property_read_bool(np, "skyworks,ignore-pwm"); > + pdata->dpwm_mode =3D of_property_read_bool(np, "skyworks,dpwm-mode"); > + pdata->phase_shift =3D of_property_read_bool(np, "skyworks,phase-shift"= ); > + pdata->gpio_enable =3D of_get_gpio(np, 0); > + > + ret =3D of_property_count_u32_elems(np, "led-sources"); > + if (IS_ERR_VALUE(ret)) { > + pdata->enable =3D SKY81452_EN >> CTZ(SKY81452_EN); > + } else { > + num_entry =3D ret; > + if (num_entry > 6) > + num_entry =3D 6; > + > + ret =3D of_property_read_u32_array(np, "led-sources", sources, > + num_entry); > + if (IS_ERR_VALUE(ret)) { > + dev_err(dev, "led-sources node is invalid.\n"); > + return ERR_PTR(-EINVAL); > + } > + > + pdata->enable =3D 0; > + while (--num_entry) > + pdata->enable |=3D (1 << sources[num_entry]); > + } > + > + ret =3D of_property_read_u32(np, > + "skyworks,short-detection-threshold-volt", > + &pdata->short_detection_threshold); > + if (IS_ERR_VALUE(ret)) > + pdata->short_detection_threshold =3D 7; > + > + ret =3D of_property_read_u32(np, "skyworks,current-limit-mA", > + &pdata->boost_current_limit); > + if (IS_ERR_VALUE(ret)) > + pdata->boost_current_limit =3D 2750; > + > + of_node_put(np); > + return pdata; > +} > +#else > +static struct sky81452_bl_platform_data *sky81452_bl_parse_dt( > + struct device *dev) > +{ > + return ERR_PTR(-EINVAL); > +} > +#endif > + > +static int sky81452_bl_init_device(struct regmap *regmap, > + struct sky81452_bl_platform_data *pdata) > +{ > + unsigned int value; > + > + value =3D pdata->ignore_pwm ? SKY81452_IGPW : 0; > + value |=3D pdata->dpwm_mode ? SKY81452_PWMMD : 0; > + value |=3D pdata->phase_shift ? 0 : SKY81452_PHASE; > + > + if (pdata->boost_current_limit =3D 2300) > + value |=3D SKY81452_ILIM; > + else if (pdata->boost_current_limit !=3D 2750) > + return -EINVAL; > + > + if (pdata->short_detection_threshold < 4 || > + pdata->short_detection_threshold > 7) > + return -EINVAL; > + value |=3D (7 - pdata->short_detection_threshold) << CTZ(SKY81452_VSHRT= ); > + > + return regmap_write(regmap, SKY81452_REG2, value); > +} > + > +static int sky81452_bl_probe(struct platform_device *pdev) > +{ > + struct device *dev =3D &pdev->dev; > + struct regmap *regmap =3D dev_get_drvdata(dev->parent); > + struct sky81452_bl_platform_data *pdata =3D dev_get_platdata(dev); > + struct backlight_device *bd; > + struct backlight_properties props; > + const char *name; > + int ret; > + > + if (!pdata) { > + pdata =3D sky81452_bl_parse_dt(dev); > + if (IS_ERR(pdata)) > + return PTR_ERR(pdata); > + } > + > + if (gpio_is_valid(pdata->gpio_enable)) { > + ret =3D devm_gpio_request_one(dev, pdata->gpio_enable, > + GPIOF_OUT_INIT_HIGH, "sky81452-en"); > + if (IS_ERR_VALUE(ret)) { > + dev_err(dev, "failed to request GPIO. err=3D%d\n", ret); > + return ret; > + } > + } > + > + ret =3D sky81452_bl_init_device(regmap, pdata); > + if (IS_ERR_VALUE(ret)) { > + dev_err(dev, "failed to initialize. err=3D%d\n", ret); > + return ret; > + } > + > + memset(&props, 0, sizeof(props)); > + props.max_brightness =3D SKY81452_MAX_BRIGHTNESS, > + name =3D pdata->name ? pdata->name : SKY81452_DEFAULT_NAME; > + bd =3D devm_backlight_device_register(dev, name, dev, regmap, > + &sky81452_bl_ops, &props); > + if (IS_ERR(bd)) { > + dev_err(dev, "failed to register. err=3D%ld\n", PTR_ERR(bd)); > + return PTR_ERR(bd); > + } > + > + platform_set_drvdata(pdev, bd); > + > + ret =3D sysfs_create_group(&bd->dev.kobj, &sky81452_bl_attr_group); > + if (IS_ERR_VALUE(ret)) { > + dev_err(dev, "failed to create attribute. err=3D%d\n", ret); > + return ret; > + } > + > + return ret; > +} > + > +static int sky81452_bl_remove(struct platform_device *pdev) > +{ > + const struct sky81452_bl_platform_data *pdata > + dev_get_platdata= (&pdev->dev); > + struct backlight_device *bd =3D platform_get_drvdata(pdev); > + > + sysfs_remove_group(&bd->dev.kobj, &sky81452_bl_attr_group); > + > + bd->props.power =3D FB_BLANK_UNBLANK; > + bd->props.brightness =3D 0; > + backlight_update_status(bd); > + > + if (gpio_is_valid(pdata->gpio_enable)) > + gpio_set_value_cansleep(pdata->gpio_enable, 0); > + > + return 0; > +} > + > +#ifdef CONFIG_OF > +static const struct of_device_id sky81452_bl_of_match[] =3D { > + { .compatible =3D "skyworks,sky81452-backlight", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, sky81452_bl_of_match); > +#endif > + > +static struct platform_driver sky81452_bl_driver =3D { > + .driver =3D { > + .name =3D "sky81452-backlight", > + .of_match_table =3D of_match_ptr(sky81452_bl_of_match), > + }, > + .probe =3D sky81452_bl_probe, > + .remove =3D sky81452_bl_remove, > +}; > + > +module_platform_driver(sky81452_bl_driver); > + > +MODULE_DESCRIPTION("Skyworks SKY81452 backlight driver"); > +MODULE_AUTHOR("Gyungoh Yoo "); > +MODULE_LICENSE("GPL v2"); > diff --git a/include/linux/platform_data/sky81452-backlight.h b/include/l= inux/platform_data/sky81452-backlight.h > new file mode 100644 > index 0000000..1231e9b > --- /dev/null > +++ b/include/linux/platform_data/sky81452-backlight.h > @@ -0,0 +1,46 @@ > +/* > + * sky81452.h SKY81452 backlight driver > + * > + * Copyright 2014 Skyworks Solutions Inc. > + * Author : Gyungoh Yoo > + * > + * 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. > + * > + * This program is distributed in the hope that it will be useful, but > + * WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + * > + * You should have received a copy of the GNU General Public License alo= ng > + * with this program; if not, see . > + */ > + > +#ifndef _SKY81452_BACKLIGHT_H > +#define _SKY81452_BACKLIGHT_H > + > +/** > + * struct sky81452_platform_data > + * @name: backlight driver name. > + If it is not defined, default name is lcd-backlight. > + * @gpio_enable:GPIO number which control EN pin > + * @enable: Enable mask for current sink channel 1, 2, 3, 4, 5 and 6. > + * @ignore_pwm: true if DPWMI should be ignored. > + * @dpwm_mode: true is DPWM dimming mode, otherwise Analog dimming mode. > + * @phase_shift:true is phase shift mode. > + * @short_detecion_threshold: It should be one of 4, 5, 6 and 7V. > + * @boost_current_limit: It should be one of 2300, 2750mA. > + */ > +struct sky81452_bl_platform_data { > + const char *name; > + int gpio_enable; > + unsigned int enable; > + bool ignore_pwm; > + bool dpwm_mode; > + bool phase_shift; > + unsigned int short_detection_threshold; > + unsigned int boost_current_limit; > +}; > + > +#endif --=20 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog