From 51631345afdd86b1507e23688655c01bf246a8d1 Mon Sep 17 00:00:00 2001 From: Serge Schneider Date: Mon, 2 Dec 2019 14:48:05 +0000 Subject: [PATCH 0306/1085] Add Raspberry Pi PoE+ HAT support Signed-off-by: Serge Schneider --- drivers/power/supply/Kconfig | 7 + drivers/power/supply/Makefile | 1 + drivers/power/supply/rpi_poe_power.c | 227 +++++++++++++++++++++++++++ 3 files changed, 235 insertions(+) create mode 100644 drivers/power/supply/rpi_poe_power.c --- a/drivers/power/supply/Kconfig +++ b/drivers/power/supply/Kconfig @@ -28,6 +28,13 @@ config POWER_SUPPLY_HWMON Say 'Y' here if you want power supplies to have hwmon sysfs interface too. +config RPI_POE_POWER + tristate "Raspberry Pi PoE+ HAT power supply driver" + depends on RASPBERRYPI_FIRMWARE + help + Say Y here to enable support for Raspberry Pi PoE+ (Power over Ethernet + Plus) HAT current measurement. + config APM_POWER tristate "APM emulation for class batteries" depends on APM_EMULATION --- a/drivers/power/supply/Makefile +++ b/drivers/power/supply/Makefile @@ -9,6 +9,7 @@ obj-$(CONFIG_POWER_SUPPLY) += power_supp obj-$(CONFIG_POWER_SUPPLY_HWMON) += power_supply_hwmon.o obj-$(CONFIG_GENERIC_ADC_BATTERY) += generic-adc-battery.o +obj-$(CONFIG_RPI_POE_POWER) += rpi_poe_power.o obj-$(CONFIG_APM_POWER) += apm_power.o obj-$(CONFIG_AXP20X_POWER) += axp20x_usb_power.o obj-$(CONFIG_IP5XXX_POWER) += ip5xxx_power.o --- /dev/null +++ b/drivers/power/supply/rpi_poe_power.c @@ -0,0 +1,227 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * rpi-poe-power.c - Raspberry Pi PoE+ HAT power supply driver. + * + * Copyright (C) 2019 Raspberry Pi (Trading) Ltd. + * Based on axp20x_ac_power.c by Quentin Schulz + * + * Author: Serge Schneider + */ + +#include +#include +#include +#include +#include + +#define RPI_POE_ADC_REG 0x2 +#define RPI_POE_FLAG_REG 0x4 + +#define RPI_POE_FLAG_AT BIT(0) +#define RPI_POE_FLAG_OC BIT(1) + +#define RPI_POE_CURRENT_AF_MAX (2500 * 1000) +#define RPI_POE_CURRENT_AT_MAX (5000 * 1000) + +#define DRVNAME "rpi-poe-power-supply" + +struct rpi_poe_power_supply_ctx { + struct power_supply *supply; + struct rpi_firmware *fw; +}; + +struct fw_tag_data_s { + u32 reg; + u32 val; + u32 ret; +}; + +static int write_reg(struct rpi_firmware *fw, u32 reg, u32 *val) +{ + struct fw_tag_data_s fw_tag_data = { + .reg = reg, + .val = *val + }; + int ret; + + ret = rpi_firmware_property(fw, RPI_FIRMWARE_SET_POE_HAT_VAL, + &fw_tag_data, sizeof(fw_tag_data)); + if (ret) + return ret; + else if (fw_tag_data.ret) + return -EIO; + return 0; +} + +static int read_reg(struct rpi_firmware *fw, u32 reg, u32 *val) +{ + struct fw_tag_data_s fw_tag_data = { + .reg = reg, + .val = *val + }; + int ret; + + ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_POE_HAT_VAL, + &fw_tag_data, sizeof(fw_tag_data)); + if (ret) + return ret; + else if (fw_tag_data.ret) + return -EIO; + + *val = fw_tag_data.val; + return 0; +} + +static int rpi_poe_power_supply_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *r_val) +{ + struct rpi_poe_power_supply_ctx *ctx = power_supply_get_drvdata(psy); + int ret; + unsigned int val = 0; + + switch (psp) { + case POWER_SUPPLY_PROP_HEALTH: + ret = read_reg(ctx->fw, RPI_POE_FLAG_REG, &val); + if (ret) + return ret; + + if (val & RPI_POE_FLAG_OC) { + r_val->intval = POWER_SUPPLY_HEALTH_UNSPEC_FAILURE; + val = RPI_POE_FLAG_OC; + ret = write_reg(ctx->fw, RPI_POE_FLAG_REG, &val); + if (ret) + return ret; + return 0; + } + + r_val->intval = POWER_SUPPLY_HEALTH_GOOD; + return 0; + + case POWER_SUPPLY_PROP_ONLINE: + ret = read_reg(ctx->fw, RPI_POE_ADC_REG, &val); + if (ret) + return ret; + + r_val->intval = (val > 5); + return 0; + + case POWER_SUPPLY_PROP_CURRENT_AVG: + val = 50; + ret = read_reg(ctx->fw, RPI_POE_ADC_REG, &val); + if (ret) + return ret; + val = (val * 3300)/9821; + r_val->intval = val * 1000; + return 0; + + case POWER_SUPPLY_PROP_CURRENT_NOW: + ret = read_reg(ctx->fw, RPI_POE_ADC_REG, &val); + if (ret) + return ret; + val = (val * 3300)/9821; + r_val->intval = val * 1000; + return 0; + + case POWER_SUPPLY_PROP_CURRENT_MAX: + ret = read_reg(ctx->fw, RPI_POE_FLAG_REG, &val); + if (ret) + return ret; + + if (val & RPI_POE_FLAG_AT) { + r_val->intval = RPI_POE_CURRENT_AT_MAX; + return 0; + } + r_val->intval = RPI_POE_CURRENT_AF_MAX; + return 0; + + default: + return -EINVAL; + } + + return -EINVAL; +} + +static enum power_supply_property rpi_poe_power_supply_properties[] = { + POWER_SUPPLY_PROP_HEALTH, + POWER_SUPPLY_PROP_ONLINE, + POWER_SUPPLY_PROP_CURRENT_AVG, + POWER_SUPPLY_PROP_CURRENT_NOW, + POWER_SUPPLY_PROP_CURRENT_MAX, +}; + +static const struct power_supply_desc rpi_poe_power_supply_desc = { + .name = "rpi-poe", + .type = POWER_SUPPLY_TYPE_MAINS, + .properties = rpi_poe_power_supply_properties, + .num_properties = ARRAY_SIZE(rpi_poe_power_supply_properties), + .get_property = rpi_poe_power_supply_get_property, +}; + +static int rpi_poe_power_supply_probe(struct platform_device *pdev) +{ + struct power_supply_config psy_cfg = {}; + struct rpi_poe_power_supply_ctx *ctx; + struct device_node *fw_node; + u32 revision; + + if (!of_device_is_available(pdev->dev.of_node)) + return -ENODEV; + + fw_node = of_parse_phandle(pdev->dev.of_node, "firmware", 0); + if (!fw_node) { + dev_err(&pdev->dev, "Missing firmware node\n"); + return -ENOENT; + } + + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + ctx->fw = rpi_firmware_get(fw_node); + if (!ctx->fw) + return -EPROBE_DEFER; + if (rpi_firmware_property(ctx->fw, + RPI_FIRMWARE_GET_FIRMWARE_REVISION, + &revision, sizeof(revision))) { + dev_err(&pdev->dev, "Failed to get firmware revision\n"); + return -ENOENT; + } + if (revision < 0x60af72e8) { + dev_err(&pdev->dev, "Unsupported firmware\n"); + return -ENOENT; + } + platform_set_drvdata(pdev, ctx); + + psy_cfg.of_node = pdev->dev.of_node; + psy_cfg.drv_data = ctx; + + ctx->supply = devm_power_supply_register(&pdev->dev, + &rpi_poe_power_supply_desc, + &psy_cfg); + if (IS_ERR(ctx->supply)) + return PTR_ERR(ctx->supply); + + return 0; +} + +static const struct of_device_id of_rpi_poe_power_supply_match[] = { + { .compatible = "raspberrypi,rpi-poe-power-supply", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, of_rpi_poe_power_supply_match); + +static struct platform_driver rpi_poe_power_supply_driver = { + .probe = rpi_poe_power_supply_probe, + .driver = { + .name = DRVNAME, + .of_match_table = of_rpi_poe_power_supply_match + }, +}; + +module_platform_driver(rpi_poe_power_supply_driver); + +MODULE_AUTHOR("Serge Schneider "); +MODULE_ALIAS("platform:" DRVNAME); +MODULE_DESCRIPTION("Raspberry Pi PoE+ HAT power supply driver"); +MODULE_LICENSE("GPL");