Hi Vadim, On 07/26/2017 04:45 PM, Vadim Pasternak wrote: > Hi Jacek, > > Thank you very much for your comments. You're welcome. >> -----Original Message----- >> From: Jacek Anaszewski [mailto:jacek.anaszewski@xxxxxxxxx] >> Sent: Tuesday, July 25, 2017 10:56 PM >> To: Vadim Pasternak <vadimp@xxxxxxxxxxxx>; >> j.anaszewski@xxxxxxxxxxx; rpurdie@xxxxxxxxx >> Cc: linux-leds@xxxxxxxxxxxxxxx; lee.jones@xxxxxxxxxx; robh+dt@xxxxxxxxxx; >> jiri@xxxxxxxxxxx >> Subject: Re: [patch v1 1/1] leds: add driver for support Mellanox regmap LEDs >> for BMC >> >> Hi Vadim, >> >> Thanks for the patch. Please refer to my remarks in the code below. >> >> On 07/25/2017 06:54 PM, Vadim Pasternak wrote: >>> Driver obtains LED devices according to system configuration, provided >>> through the platform data, >> >> Why platform data? This is confusing since you're providing DT bindings in >> 1/2. > > I think, I'll just remove "provided through the platform data". > I put it there, because I am getting data by dev_get_platdata and > I'd like this driver to work not only from DT bindings, but also through the > APIs like platform_device_register_resndata for f.e. x86 systems. Ah, OK, I just didn't analyze the rest of series carefully enough. >>> like mlxreg:status:green or mlxreg:status:amber and creates devices in >>> form: "devicename:colour:function". >>> The full path is to be: >>> /sys/class/leds/mlxreg\:status\:amber/brightness >>> After timer trigger activation: >>> echo timer > /sys/class/leds/mlxreg\:status\:amber/trigger >>> Attributes for LED blinking will appaer in sysfs infrastructure: >>> /sys/class/leds/mlxreg\:status\:amber/delay_off >>> /sys/class/leds/mlxreg\:status\:amber/delay_on >>> >>> LED setting is controlled through the on-board programmable devices, >>> which exports its register map. This device could be attached to any >>> bus type, for which register mapping is supported. >>> >>> Signed-off-by: Vadim Pasternak <vadimp@xxxxxxxxxxxx> >>> --- >>> MAINTAINERS | 1 + >>> drivers/leds/Makefile | 1 + >>> drivers/leds/leds-mlxreg.c | 345 >>> +++++++++++++++++++++++++++++++++++++++++++++ >>> 3 files changed, 347 insertions(+) >>> create mode 100644 drivers/leds/leds-mlxreg.c >>> >>> diff --git a/MAINTAINERS b/MAINTAINERS index 205d397..ac6b0d0 100644 >>> --- a/MAINTAINERS >>> +++ b/MAINTAINERS >>> @@ -8566,6 +8566,7 @@ M: Vadim Pasternak <vadimp@xxxxxxxxxxxx> >>> L: linux-leds@xxxxxxxxxxxxxxx >>> S: Supported >>> F: drivers/leds/leds-mlxcpld.c >>> +F: drivers/leds/leds-mlxreg.c >>> F: Documentation/leds/leds-mlxcpld.txt >>> >>> MELLANOX PLATFORM DRIVER >>> diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index >>> 909dae6..3eb76e5 100644 >>> --- a/drivers/leds/Makefile >>> +++ b/drivers/leds/Makefile >>> @@ -69,6 +69,7 @@ obj-$(CONFIG_LEDS_IS31FL319X) += >> leds-is31fl319x.o >>> obj-$(CONFIG_LEDS_IS31FL32XX) += leds-is31fl32xx.o >>> obj-$(CONFIG_LEDS_PM8058) += leds-pm8058.o >>> obj-$(CONFIG_LEDS_MLXCPLD) += leds-mlxcpld.o >>> +obj-$(CONFIG_LEDS_MLXREG) += leds-mlxreg.o >>> obj-$(CONFIG_LEDS_NIC78BX) += leds-nic78bx.o >>> obj-$(CONFIG_LEDS_MT6323) += leds-mt6323.o >>> >>> diff --git a/drivers/leds/leds-mlxreg.c b/drivers/leds/leds-mlxreg.c >>> new file mode 100644 index 0000000..bc1a6c3 >>> --- /dev/null >>> +++ b/drivers/leds/leds-mlxreg.c >>> @@ -0,0 +1,345 @@ >>> +/* >>> + * Copyright (c) 2017 Mellanox Technologies. All rights reserved. >>> + * Copyright (c) 2017 Vadim Pasternak <vadimp@xxxxxxxxxxxx> >>> + * >>> + * Redistribution and use in source and binary forms, with or without >>> + * modification, are permitted provided that the following conditions are >> met: >>> + * >>> + * 1. Redistributions of source code must retain the above copyright >>> + * notice, this list of conditions and the following disclaimer. >>> + * 2. Redistributions in binary form must reproduce the above copyright >>> + * notice, this list of conditions and the following disclaimer in the >>> + * documentation and/or other materials provided with the distribution. >>> + * 3. Neither the names of the copyright holders nor the names of its >>> + * contributors may be used to endorse or promote products derived >> from >>> + * this software without specific prior written permission. >>> + * >>> + * Alternatively, this software may be distributed under the terms of >>> +the >>> + * GNU General Public License ("GPL") version 2 as published by the >>> +Free >>> + * Software Foundation. >>> + * >>> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND >> CONTRIBUTORS "AS IS" >>> + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT >> LIMITED >>> +TO, THE >>> + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A >> PARTICULAR >>> +PURPOSE >>> + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR >>> +CONTRIBUTORS BE >>> + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, >>> +OR >>> + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, >> PROCUREMENT >>> +OF >>> + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR >>> +BUSINESS >>> + * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, >>> +WHETHER IN >>> + * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR >>> +OTHERWISE) >>> + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF >>> +ADVISED OF THE >>> + * POSSIBILITY OF SUCH DAMAGE. >>> + */ >>> + >>> +#include <linux/bitops.h> >>> +#include <linux/device.h> >>> +#include <linux/interrupt.h> >>> +#include <linux/leds.h> >>> +#include <linux/module.h> >>> +#include <linux/io.h> >>> +#include <linux/of_device.h> >>> +#include <linux/platform_data/mlxreg.h> #include >>> +<linux/platform_device.h> #include <linux/regmap.h> #include >>> +<linux/wait.h> #include <linux/workqueue.h> >>> + >>> +#define MLXREG_LED_NAME "mlxreg" >> >> Why can't it be taken from DT? >> >>> + >>> +/* Codes for LEDs. */ >>> +#define MLXREG_LED_OFFSET_HALF 0x01 /* Offset from solid: 3Hz >> blink */ >>> +#define MLXREG_LED_OFFSET_FULL 0x02 /* Offset from solid: 6Hz >> blink */ >>> +#define MLXREG_LED_IS_OFF 0x00 /* Off */ >>> +#define MLXREG_LED_RED_SOLID 0x05 /* Solid red */ >>> +#define MLXREG_LED_GREEN_SOLID 0x0D /* Solid green */ >>> +#define MLXREG_LED_AMBER_SOLID 0x09 /* Solid amber */ >>> +#define MLXREG_LED_BLINK_3HZ 167 /* ~167 msec off/on - HW >> support */ >>> +#define MLXREG_LED_BLINK_6HZ 83 /* ~83 msec off/on - HW support >> */ >>> +#define MLXREG_LED_MAX_DEFERRED 32 /* Max deferred >> operations for LED set */ >>> + >>> +#define cdev_to_priv(c) container_of(c, struct mlxreg_core_led_data, >>> +led_cdev) >>> + >>> +/** >>> + * struct mlxreg_led_priv_data - platform private data: >>> + * >>> + * @pdev: platform device; >>> + * @pdata: platform data; >>> + * @access_lock: mutex for attribute IO access; */ struct >>> +mlxreg_led_priv_data { >>> + struct platform_device *pdev; >>> + struct mlxreg_core_led_platform_data *pdata; >>> + struct mutex access_lock; /* protect IO operations */ }; >>> + >>> +#define MLXREG_MAP priv->pdata->regmap >>> + >>> +static int >>> +mlxreg_led_store_hw(struct mlxreg_core_led_data *led_pdata, u8 vset) >>> +{ >>> + struct mlxreg_led_priv_data *priv = led_pdata->data_parent; >>> + u32 regval; >>> + u32 nib; >>> + int ret; >>> + >>> + /* >>> + * Each LED is controlled through low or high nibble of the relevant >>> + * register byte. Register offset is specified by off parameter. >>> + * Parameter vset provides color code: 0x0 for off, 0x5 for solid red, >>> + * 0x6 for 3Hz blink red, 0xd for solid green, 0xe for 3Hz blink >>> + * green. >>> + * Parameter mask specifies which nibble is used for specific LED: >> mask >>> + * 0xf0 - lower nibble is to be used (bits from 0 to 3), mask 0x0f - >>> + * higher nibble (bits from 4 to 7). >>> + */ >>> + mutex_lock(&priv->access_lock); >>> + >>> + ret = regmap_read(MLXREG_MAP, led_pdata->led->reg, ®val); >>> + if (ret) >>> + goto access_error; >>> + >>> + nib = (ror32(led_pdata->led->mask, led_pdata->led->bit) == 0xf0) ? >>> + rol32(vset, led_pdata->led->bit) : >>> + rol32(vset, led_pdata->led->bit + 4); >>> + regval = (regval & led_pdata->led->mask) | nib; >>> + >>> + ret = regmap_write(MLXREG_MAP, led_pdata->led->reg, regval); >>> + >>> +access_error: >>> + mutex_unlock(&priv->access_lock); >>> + >>> + return ret; >>> +} >>> + >>> +static enum led_brightness >>> +mlxreg_led_get_hw(struct mlxreg_core_led_data *led_pdata) { >>> + struct mlxreg_led_priv_data *priv = led_pdata->data_parent; >>> + u32 regval; >>> + int ret; >>> + >>> + /* >>> + * Each LED is controlled through low or high nibble of the relevant >>> + * register byte. Register offset is specified by off parameter. >>> + * Parameter vset provides color code: 0x0 for off, 0x5 for solid red, >>> + * 0x6 for 3Hz blink red, 0xd for solid green, 0xe for 3Hz blink >>> + * green. >>> + * Parameter mask specifies which nibble is used for specific LED: >> mask >>> + * 0xf0 - lower nibble is to be used (bits from 0 to 3), mask 0x0f - >>> + * higher nibble (bits from 4 to 7). >>> + */ >>> + ret = regmap_read(MLXREG_MAP, led_pdata->led->reg, ®val); >>> + if (ret < 0) { >>> + dev_warn(led_pdata->led_cdev.dev, "Failed to get current >> brightness, error: %d\n", >>> + ret); >>> + /* Assume the LED is OFF */ >>> + ret = LED_OFF; >>> + goto access_error; >>> + } >>> + >>> + regval = regval & ~led_pdata->led->mask; >>> + regval = (ror32(led_pdata->led->mask, led_pdata->led->bit) == 0xf0) >> ? >>> + ror32(regval, led_pdata->led->bit) : >>> + ror32(regval, led_pdata->led->bit + 4); >>> + if (regval >= led_pdata->base_color && >>> + regval <= (led_pdata->base_color + MLXREG_LED_OFFSET_FULL)) >>> + ret = LED_FULL; >>> + else >>> + ret = LED_OFF; >>> + >>> +access_error: >>> + >>> + return ret; >>> +} >>> + >>> +static void >>> +mlxreg_led_brightness_set(struct led_classdev *cled, enum >>> +led_brightness value) { >>> + struct mlxreg_core_led_data *led_pdata = cdev_to_priv(cled); >>> + >>> + if (in_interrupt()) { >> >> You wouldn't have to bother with the context you are called from if only you >> used brightness_set_blocking op. >> > > Thanks for this pointer. Missed it. > I'll issue v2 for both patches, since with this change I can remove these three fields from mlxreg_core_led_data > u32 bitset; > u8 set_count; > struct delayed_work dwork_led; > >>> + /* >>> + * Handle hw access to LED in workqueue to avoid I2C locking >> in >>> + * interrupt mode. Skip if deferred operations counter is at >>> + * maximum value. >>> + */ >>> + if (led_pdata->set_count == MLXREG_LED_MAX_DEFERRED - >> 1) >>> + return; >>> + >>> + if (!!value) >>> + led_pdata->bitset |= BIT(led_pdata->set_count); >>> + led_pdata->set_count++; >>> + >>> + schedule_delayed_work(&led_pdata->dwork_led, 0); >> >> Similarly you could get rid of the workqueue then. It is implemented >> internally in the LED core now. >> >>> + >>> + return; >>> + } >>> + >>> + if (value) >>> + mlxreg_led_store_hw(led_pdata, led_pdata->base_color); >>> + else >>> + mlxreg_led_store_hw(led_pdata, MLXREG_LED_IS_OFF); } >>> + >>> +static enum led_brightness >>> +mlxreg_led_brightness_get(struct led_classdev *cled) { >>> + struct mlxreg_core_led_data *led_pdata = cdev_to_priv(cled); >>> + >>> + return mlxreg_led_get_hw(led_pdata); } >>> + >>> +static int >>> +mlxreg_led_blink_set(struct led_classdev *cled, unsigned long >> *delay_on, >>> + unsigned long *delay_off) >>> +{ >>> + struct mlxreg_core_led_data *led_pdata = cdev_to_priv(cled); >>> + int err; >>> + >>> + /* >>> + * HW supports two types of blinking: full (6Hz) and half (3Hz). >>> + * For delay on/off zero LED is setting to solid color. For others >>> + * combination blinking is to be controlled by the software timer. >>> + */ >>> + if (!(*delay_on == 0 && *delay_off == 0) && >>> + !(*delay_on == MLXREG_LED_BLINK_3HZ && >>> + *delay_off == MLXREG_LED_BLINK_3HZ) && >>> + !(*delay_on == MLXREG_LED_BLINK_6HZ && >>> + *delay_off == MLXREG_LED_BLINK_6HZ)) >>> + return -EINVAL; >>> + >>> + if (*delay_on == MLXREG_LED_BLINK_6HZ) >>> + err = mlxreg_led_store_hw(led_pdata, led_pdata- >>> base_color + >>> + MLXREG_LED_OFFSET_FULL); >>> + else if (*delay_on == MLXREG_LED_BLINK_3HZ) >>> + err = mlxreg_led_store_hw(led_pdata, led_pdata- >>> base_color + >>> + MLXREG_LED_OFFSET_HALF); >>> + else >>> + err = mlxreg_led_store_hw(led_pdata, led_pdata- >>> base_color); >>> + >>> + return err; >>> +} >>> + >>> +static void mlxreg_led_handler(struct work_struct *work) { >>> + struct mlxreg_core_led_data *led_pdata = container_of(work, >>> + struct mlxreg_core_led_data, dwork_led.work); >>> + >>> + if (led_pdata->bitset & BIT(0)) >>> + mlxreg_led_store_hw(led_pdata, led_pdata->base_color); >>> + else >>> + mlxreg_led_store_hw(led_pdata, MLXREG_LED_IS_OFF); >>> + >>> + led_pdata->bitset >>= 1; >>> + led_pdata->set_count--; >>> +} >>> + >>> +#define MLXREG_CDEV(i) pdata->data[i].led_cdev >>> + >>> +static int mlxreg_led_config(struct mlxreg_led_priv_data *priv) { >>> + struct mlxreg_core_led_platform_data *pdata = priv->pdata; >>> + struct mlxreg_core_data *data = pdata->data->led; >>> + int brightness; >>> + int i; >>> + int err; >>> + >>> + for (i = 0; i < pdata->counter; i++, data++) { >>> + pdata->data[i].data_parent = priv; >>> + if (strstr(data->label, "red")) { >>> + brightness = LED_OFF; >>> + pdata->data[i].base_color = >> MLXREG_LED_RED_SOLID; >>> + } else if (strstr(data->label, "amber")) { >>> + brightness = LED_OFF; >>> + pdata->data[i].base_color = >> MLXREG_LED_AMBER_SOLID; >>> + } else { >>> + brightness = LED_OFF; >>> + pdata->data[i].base_color = >> MLXREG_LED_GREEN_SOLID; >>> + } >>> + sprintf(pdata->data[i].led_cdev_name, "%s:%s", >>> + MLXREG_LED_NAME, data->label); >> >> You should take LED name directly from the of_node. Either child DT node >> name or label property contained by it. >> See Documentation/devicetree/bindings/leds/common.txt. > > LED name is coming from DT: > status-green { > reg = <0x20>; > mask = <0xf0>; > }; > status-amber { > reg = <0x20>; > mask = <0xf0>; > }; > fan1-green { > reg = <0x21>; > mask = <0xf0>; > }; > In /sys/class/leds it's shown, like: > mlxreg:fan1:green > mlxreg:status:amber > mlxreg:fan1: red > > I used mlxreg as a device prefix. > Do you think it should be removed? No, this seems to be correct. >>> + MLXREG_CDEV(i).name = pdata->data[i].led_cdev_name; >> >> Let's avoid using these type of macros in favor of temporary variables. >> However let's agree about final shape thereof after core mfd driver gets >> reviewed. >> >> >>> + MLXREG_CDEV(i).brightness = brightness; >>> + MLXREG_CDEV(i).max_brightness = 1; >>> + MLXREG_CDEV(i).brightness_set = >> mlxreg_led_brightness_set; >>> + MLXREG_CDEV(i).brightness_get = >> mlxreg_led_brightness_get; >>> + MLXREG_CDEV(i).blink_set = mlxreg_led_blink_set; >>> + MLXREG_CDEV(i).flags = LED_CORE_SUSPENDRESUME; >>> + pdata->data[i].led = data; >>> + err = devm_led_classdev_register(&priv->pdev->dev, >>> + &MLXREG_CDEV(i)); >>> + if (err) >>> + return err; >>> + >>> + if (MLXREG_CDEV(i).brightness) >>> + mlxreg_led_brightness_set( >>> + &MLXREG_CDEV(i), >>> + MLXREG_CDEV(i).brightness); >>> + dev_info(MLXREG_CDEV(i).dev, >>> + "label: %s, mask: 0x%02x, offset:0x%02x\n", >>> + data->label, data->mask, data->reg); >>> + >>> + INIT_DELAYED_WORK(&pdata->data[i].dwork_led, >>> + mlxreg_led_handler); >>> + } >>> + >>> + return 0; >>> +} >>> + >>> +static int mlxreg_led_probe(struct platform_device *pdev) { >>> + struct mlxreg_core_led_platform_data *pdata; >>> + struct mlxreg_led_priv_data *priv; >>> + >>> + pdata = dev_get_platdata(&pdev->dev); >>> + if (!pdata) { >>> + dev_err(&pdev->dev, "Failed to get platform data.\n"); >>> + return -EINVAL; >>> + } >>> + >>> + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); >>> + if (!priv) >>> + return -ENOMEM; >>> + >>> + mutex_init(&priv->access_lock); >>> + priv->pdev = pdev; >>> + priv->pdata = pdata; >>> + >>> + return mlxreg_led_config(priv); >>> +} >>> + >>> +static int mlxreg_led_remove(struct platform_device *pdev) { >>> + struct mlxreg_led_priv_data *priv = dev_get_drvdata(&pdev->dev); >>> + struct mlxreg_core_led_platform_data *pdata = priv->pdata; >>> + int i; >>> + >>> + for (i = 0; i < pdata->counter; i++) >>> + cancel_delayed_work(&pdata->data[i].dwork_led); >>> + >>> + mutex_unlock(&priv->access_lock); >>> + >>> + return 0; >>> +} >>> + >>> +static const struct of_device_id mlxreg_led_dt_match[] = { >>> + { .compatible = "mellanox,leds-mlxreg" }, >>> + { }, >>> +}; >>> +MODULE_DEVICE_TABLE(of, mlxreg_dt_match); >>> + >>> +static struct platform_driver mlxreg_led_driver = { >>> + .driver = { >>> + .name = "leds-mlxreg", >>> + .of_match_table = of_match_ptr(mlxreg_led_dt_match), >>> + }, >>> + .probe = mlxreg_led_probe, >>> + .remove = mlxreg_led_remove, >>> +}; >>> + >>> +module_platform_driver(mlxreg_led_driver); >>> + >>> +MODULE_AUTHOR("Vadim Pasternak <vadimp@xxxxxxxxxxxx>"); >>> +MODULE_DESCRIPTION("Mellanox LED regmap driver"); >>> +MODULE_LICENSE("Dual BSD/GPL"); MODULE_ALIAS("platform:leds- >> mlxreg"); >>> >> >> -- >> Best regards, >> Jacek Anaszewski > -- Best regards, Jacek Anaszewski
