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1// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)2//3// Copyright (c) 2018 Mellanox Technologies. All rights reserved.4// Copyright (c) 2018 Vadim Pasternak <vadimp@mellanox.com>5 6#include <linux/bitops.h>7#include <linux/device.h>8#include <linux/io.h>9#include <linux/leds.h>10#include <linux/module.h>11#include <linux/platform_data/mlxreg.h>12#include <linux/platform_device.h>13#include <linux/regmap.h>14 15/* Codes for LEDs. */16#define MLXREG_LED_OFFSET_BLINK_3HZ 0x01 /* Offset from solid: 3Hz blink */17#define MLXREG_LED_OFFSET_BLINK_6HZ 0x02 /* Offset from solid: 6Hz blink */18#define MLXREG_LED_IS_OFF 0x00 /* Off */19#define MLXREG_LED_RED_SOLID 0x05 /* Solid red */20#define MLXREG_LED_GREEN_SOLID 0x0D /* Solid green */21#define MLXREG_LED_AMBER_SOLID 0x09 /* Solid amber */22#define MLXREG_LED_BLINK_3HZ 167 /* ~167 msec off/on - HW support */23#define MLXREG_LED_BLINK_6HZ 83 /* ~83 msec off/on - HW support */24#define MLXREG_LED_CAPABILITY_CLEAR GENMASK(31, 8) /* Clear mask */25 26/**27 * struct mlxreg_led_data - led control data:28 *29 * @data: led configuration data;30 * @led_cdev: led class data;31 * @base_color: base led color (other colors have constant offset from base);32 * @data_parent: pointer to private device control data of parent;33 * @led_cdev_name: class device name34 */35struct mlxreg_led_data {36 struct mlxreg_core_data *data;37 struct led_classdev led_cdev;38 u8 base_color;39 void *data_parent;40 char led_cdev_name[MLXREG_CORE_LABEL_MAX_SIZE];41};42 43#define cdev_to_priv(c) container_of(c, struct mlxreg_led_data, led_cdev)44 45/**46 * struct mlxreg_led_priv_data - platform private data:47 *48 * @pdev: platform device;49 * @pdata: platform data;50 * @access_lock: mutex for attribute IO access;51 */52struct mlxreg_led_priv_data {53 struct platform_device *pdev;54 struct mlxreg_core_platform_data *pdata;55 struct mutex access_lock; /* protect IO operations */56};57 58static int59mlxreg_led_store_hw(struct mlxreg_led_data *led_data, u8 vset)60{61 struct mlxreg_led_priv_data *priv = led_data->data_parent;62 struct mlxreg_core_platform_data *led_pdata = priv->pdata;63 struct mlxreg_core_data *data = led_data->data;64 u32 regval;65 u32 nib;66 int ret;67 68 /*69 * Each LED is controlled through low or high nibble of the relevant70 * register byte. Register offset is specified by off parameter.71 * Parameter vset provides color code: 0x0 for off, 0x5 for solid red,72 * 0x6 for 3Hz blink red, 0xd for solid green, 0xe for 3Hz blink73 * green.74 * Parameter mask specifies which nibble is used for specific LED: mask75 * 0xf0 - lower nibble is to be used (bits from 0 to 3), mask 0x0f -76 * higher nibble (bits from 4 to 7).77 */78 mutex_lock(&priv->access_lock);79 80 ret = regmap_read(led_pdata->regmap, data->reg, ®val);81 if (ret)82 goto access_error;83 84 nib = (ror32(data->mask, data->bit) == 0xf0) ? rol32(vset, data->bit) :85 rol32(vset, data->bit + 4);86 regval = (regval & data->mask) | nib;87 88 ret = regmap_write(led_pdata->regmap, data->reg, regval);89 90access_error:91 mutex_unlock(&priv->access_lock);92 93 return ret;94}95 96static enum led_brightness97mlxreg_led_get_hw(struct mlxreg_led_data *led_data)98{99 struct mlxreg_led_priv_data *priv = led_data->data_parent;100 struct mlxreg_core_platform_data *led_pdata = priv->pdata;101 struct mlxreg_core_data *data = led_data->data;102 u32 regval;103 int err;104 105 /*106 * Each LED is controlled through low or high nibble of the relevant107 * register byte. Register offset is specified by off parameter.108 * Parameter vset provides color code: 0x0 for off, 0x5 for solid red,109 * 0x6 for 3Hz blink red, 0xd for solid green, 0xe for 3Hz blink110 * green.111 * Parameter mask specifies which nibble is used for specific LED: mask112 * 0xf0 - lower nibble is to be used (bits from 0 to 3), mask 0x0f -113 * higher nibble (bits from 4 to 7).114 */115 err = regmap_read(led_pdata->regmap, data->reg, ®val);116 if (err < 0) {117 dev_warn(led_data->led_cdev.dev, "Failed to get current brightness, error: %d\n",118 err);119 /* Assume the LED is OFF */120 return LED_OFF;121 }122 123 regval = regval & ~data->mask;124 regval = (ror32(data->mask, data->bit) == 0xf0) ? ror32(regval,125 data->bit) : ror32(regval, data->bit + 4);126 if (regval >= led_data->base_color &&127 regval <= (led_data->base_color + MLXREG_LED_OFFSET_BLINK_6HZ))128 return LED_FULL;129 130 return LED_OFF;131}132 133static int134mlxreg_led_brightness_set(struct led_classdev *cled, enum led_brightness value)135{136 struct mlxreg_led_data *led_data = cdev_to_priv(cled);137 138 if (value)139 return mlxreg_led_store_hw(led_data, led_data->base_color);140 else141 return mlxreg_led_store_hw(led_data, MLXREG_LED_IS_OFF);142}143 144static enum led_brightness145mlxreg_led_brightness_get(struct led_classdev *cled)146{147 struct mlxreg_led_data *led_data = cdev_to_priv(cled);148 149 return mlxreg_led_get_hw(led_data);150}151 152static int153mlxreg_led_blink_set(struct led_classdev *cled, unsigned long *delay_on,154 unsigned long *delay_off)155{156 struct mlxreg_led_data *led_data = cdev_to_priv(cled);157 int err;158 159 /*160 * HW supports two types of blinking: full (6Hz) and half (3Hz).161 * For delay on/off zero LED is setting to solid color. For others162 * combination blinking is to be controlled by the software timer.163 */164 if (!(*delay_on == 0 && *delay_off == 0) &&165 !(*delay_on == MLXREG_LED_BLINK_3HZ &&166 *delay_off == MLXREG_LED_BLINK_3HZ) &&167 !(*delay_on == MLXREG_LED_BLINK_6HZ &&168 *delay_off == MLXREG_LED_BLINK_6HZ))169 return -EINVAL;170 171 if (*delay_on == MLXREG_LED_BLINK_6HZ)172 err = mlxreg_led_store_hw(led_data, led_data->base_color +173 MLXREG_LED_OFFSET_BLINK_6HZ);174 else if (*delay_on == MLXREG_LED_BLINK_3HZ)175 err = mlxreg_led_store_hw(led_data, led_data->base_color +176 MLXREG_LED_OFFSET_BLINK_3HZ);177 else178 err = mlxreg_led_store_hw(led_data, led_data->base_color);179 180 return err;181}182 183static int mlxreg_led_config(struct mlxreg_led_priv_data *priv)184{185 struct mlxreg_core_platform_data *led_pdata = priv->pdata;186 struct mlxreg_core_data *data = led_pdata->data;187 struct mlxreg_led_data *led_data;188 struct led_classdev *led_cdev;189 enum led_brightness brightness;190 u32 regval;191 int i;192 int err;193 194 for (i = 0; i < led_pdata->counter; i++, data++) {195 led_data = devm_kzalloc(&priv->pdev->dev, sizeof(*led_data),196 GFP_KERNEL);197 if (!led_data)198 return -ENOMEM;199 200 if (data->capability) {201 err = regmap_read(led_pdata->regmap, data->capability,202 ®val);203 if (err) {204 dev_err(&priv->pdev->dev, "Failed to query capability register\n");205 return err;206 }207 if (!(regval & data->bit))208 continue;209 /*210 * Field "bit" can contain one capability bit in 0 byte211 * and offset bit in 1-3 bytes. Clear capability bit and212 * keep only offset bit.213 */214 data->bit &= MLXREG_LED_CAPABILITY_CLEAR;215 }216 217 led_cdev = &led_data->led_cdev;218 led_data->data_parent = priv;219 if (strstr(data->label, "red") ||220 strstr(data->label, "orange")) {221 brightness = LED_OFF;222 led_data->base_color = MLXREG_LED_RED_SOLID;223 } else if (strstr(data->label, "amber")) {224 brightness = LED_OFF;225 led_data->base_color = MLXREG_LED_AMBER_SOLID;226 } else {227 brightness = LED_OFF;228 led_data->base_color = MLXREG_LED_GREEN_SOLID;229 }230 snprintf(led_data->led_cdev_name, sizeof(led_data->led_cdev_name),231 "mlxreg:%s", data->label);232 led_cdev->name = led_data->led_cdev_name;233 led_cdev->brightness = brightness;234 led_cdev->max_brightness = LED_ON;235 led_cdev->brightness_set_blocking =236 mlxreg_led_brightness_set;237 led_cdev->brightness_get = mlxreg_led_brightness_get;238 led_cdev->blink_set = mlxreg_led_blink_set;239 led_cdev->flags = LED_CORE_SUSPENDRESUME;240 led_data->data = data;241 err = devm_led_classdev_register(&priv->pdev->dev, led_cdev);242 if (err)243 return err;244 245 if (led_cdev->brightness)246 mlxreg_led_brightness_set(led_cdev,247 led_cdev->brightness);248 dev_info(led_cdev->dev, "label: %s, mask: 0x%02x, offset:0x%02x\n",249 data->label, data->mask, data->reg);250 }251 252 return 0;253}254 255static int mlxreg_led_probe(struct platform_device *pdev)256{257 struct mlxreg_core_platform_data *led_pdata;258 struct mlxreg_led_priv_data *priv;259 int err;260 261 led_pdata = dev_get_platdata(&pdev->dev);262 if (!led_pdata) {263 dev_err(&pdev->dev, "Failed to get platform data.\n");264 return -EINVAL;265 }266 267 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);268 if (!priv)269 return -ENOMEM;270 271 err = devm_mutex_init(&pdev->dev, &priv->access_lock);272 if (err)273 return err;274 275 priv->pdev = pdev;276 priv->pdata = led_pdata;277 278 return mlxreg_led_config(priv);279}280 281static struct platform_driver mlxreg_led_driver = {282 .driver = {283 .name = "leds-mlxreg",284 },285 .probe = mlxreg_led_probe,286};287 288module_platform_driver(mlxreg_led_driver);289 290MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");291MODULE_DESCRIPTION("Mellanox LED regmap driver");292MODULE_LICENSE("Dual BSD/GPL");293MODULE_ALIAS("platform:leds-mlxreg");294