From patchwork Wed May 13 11:56:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Reichel X-Patchwork-Id: 212044 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6CC96C2D0FC for ; Wed, 13 May 2020 11:56:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DD7D20740 for ; Wed, 13 May 2020 11:56:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726024AbgEML4V (ORCPT ); Wed, 13 May 2020 07:56:21 -0400 Received: from bhuna.collabora.co.uk ([46.235.227.227]:48104 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730004AbgEML4S (ORCPT ); Wed, 13 May 2020 07:56:18 -0400 Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: sre) with ESMTPSA id D19482A28AA Received: by jupiter.universe (Postfix, from userid 1000) id 6FDD64800F8; Wed, 13 May 2020 13:56:13 +0200 (CEST) From: Sebastian Reichel To: Sebastian Reichel , Rob Herring Cc: linux-pm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@collabora.com, Sebastian Reichel Subject: [PATCHv1 1/2] power: supply: gpio-charger: add charge-current-limit feature Date: Wed, 13 May 2020 13:56:00 +0200 Message-Id: <20200513115601.360642-1-sebastian.reichel@collabora.com> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Add new charge-current-limit feature to gpio-charger. This also makes the online status GPIO optional, since hardware might only expose the charge-current-limit feature and there is no good reason to have it mandatory now that different GPIOs are supported. Signed-off-by: Sebastian Reichel --- .../bindings/power/supply/gpio-charger.txt | 11 +- drivers/power/supply/gpio-charger.c | 176 ++++++++++++++++-- 2 files changed, 174 insertions(+), 13 deletions(-) diff --git a/Documentation/devicetree/bindings/power/supply/gpio-charger.txt b/Documentation/devicetree/bindings/power/supply/gpio-charger.txt index 0fb33b2c62a6..dbfd29029f69 100644 --- a/Documentation/devicetree/bindings/power/supply/gpio-charger.txt +++ b/Documentation/devicetree/bindings/power/supply/gpio-charger.txt @@ -2,8 +2,6 @@ gpio-charger Required properties : - compatible : "gpio-charger" - - gpios : GPIO indicating the charger presence. - See GPIO binding in bindings/gpio/gpio.txt . - charger-type : power supply type, one of unknown battery @@ -15,7 +13,13 @@ Required properties : usb-aca (USB accessory charger adapter) Optional properties: + - gpios : GPIO indicating the charger presence. + See GPIO binding in bindings/gpio/gpio.txt . - charge-status-gpios: GPIO indicating whether a battery is charging. + - charge-current-limit-gpios: Output GPIOs specifiers for limiting the charge current + - charge-current-limit-mapping: List of touples with current in uA and a GPIO bitmap (in this order). + The GPIOs are encoded in the same order as specified in charge-current-limit-gpios. + The touples must be provided in descending order of the current limit. Example: @@ -24,6 +28,9 @@ Example: charger-type = "usb-sdp"; gpios = <&gpd 28 GPIO_ACTIVE_LOW>; charge-status-gpios = <&gpc 27 GPIO_ACTIVE_LOW>; + + charge-current-limit-gpios = <&gpioA 11 GPIO_ACTIVE_HIGH>, <&gpioA 12 GPIO_ACTIVE_HIGH>; + charge-current-limit-mapping = <2500000 0x00>, <700000 0x01>, <0 0x02>; }; battery { diff --git a/drivers/power/supply/gpio-charger.c b/drivers/power/supply/gpio-charger.c index 1b959c7f8b0e..4a5eac7cc36c 100644 --- a/drivers/power/supply/gpio-charger.c +++ b/drivers/power/supply/gpio-charger.c @@ -18,7 +18,13 @@ #include +struct gpio_mapping { + u32 limit_ua; + u32 gpiodata; +} __packed; + struct gpio_charger { + struct device *dev; unsigned int irq; unsigned int charge_status_irq; bool wakeup_enabled; @@ -27,6 +33,11 @@ struct gpio_charger { struct power_supply_desc charger_desc; struct gpio_desc *gpiod; struct gpio_desc *charge_status; + + struct gpio_descs *current_limit_gpios; + struct gpio_mapping *current_limit_map; + u32 current_limit_map_size; + u32 charge_current_limit; }; static irqreturn_t gpio_charger_irq(int irq, void *devid) @@ -43,6 +54,35 @@ static inline struct gpio_charger *psy_to_gpio_charger(struct power_supply *psy) return power_supply_get_drvdata(psy); } +static int set_charge_current_limit(struct gpio_charger *gpio_charger, int val) +{ + struct gpio_mapping mapping; + int ndescs = gpio_charger->current_limit_gpios->ndescs; + struct gpio_desc **gpios = gpio_charger->current_limit_gpios->desc; + int i; + + if (!gpio_charger->current_limit_map_size) + return -EINVAL; + + for (i = 0; i < gpio_charger->current_limit_map_size; i++) { + if (gpio_charger->current_limit_map[i].limit_ua <= val) + break; + } + mapping = gpio_charger->current_limit_map[i]; + + for (i = 0; i < ndescs; i++) { + bool val = (mapping.gpiodata >> i) & 1; + gpiod_set_value_cansleep(gpios[ndescs-i-1], val); + } + + gpio_charger->charge_current_limit = mapping.limit_ua; + + dev_dbg(gpio_charger->dev, "set charge current limit to %d (requested: %d)\n", + gpio_charger->charge_current_limit, val); + + return 0; +} + static int gpio_charger_get_property(struct power_supply *psy, enum power_supply_property psp, union power_supply_propval *val) { @@ -58,6 +98,9 @@ static int gpio_charger_get_property(struct power_supply *psy, else val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING; break; + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX: + val->intval = gpio_charger->charge_current_limit; + break; default: return -EINVAL; } @@ -65,6 +108,34 @@ static int gpio_charger_get_property(struct power_supply *psy, return 0; } +static int gpio_charger_set_property(struct power_supply *psy, + enum power_supply_property psp, const union power_supply_propval *val) +{ + struct gpio_charger *gpio_charger = psy_to_gpio_charger(psy); + + switch (psp) { + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX: + return set_charge_current_limit(gpio_charger, val->intval); + default: + return -EINVAL; + } + + return 0; +} + +static int gpio_charger_property_is_writeable(struct power_supply *psy, + enum power_supply_property psp) +{ + switch (psp) { + case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX: + return 1; + default: + break; + } + + return 0; +} + static enum power_supply_type gpio_charger_get_type(struct device *dev) { const char *chargetype; @@ -112,9 +183,70 @@ static int gpio_charger_get_irq(struct device *dev, void *dev_id, return irq; } +static int init_charge_current_limit(struct device *dev, + struct gpio_charger *gpio_charger) +{ + int i, len; + u32 cur_limit = U32_MAX; + + gpio_charger->current_limit_gpios = devm_gpiod_get_array_optional(dev, + "charge-current-limit", GPIOD_OUT_LOW); + if (IS_ERR(gpio_charger->current_limit_gpios)) { + dev_err(dev, "error getting current-limit GPIOs\n"); + return PTR_ERR(gpio_charger->current_limit_gpios); + } + + if (!gpio_charger->current_limit_gpios) + return 0; + + len = device_property_read_u32_array(dev, "charge-current-limit-mapping", + NULL, 0); + if (len < 0) + return len; + + if (len % 2) { + dev_err(dev, "invalid charge-current-limit-mapping length\n"); + return -EINVAL; + } + + gpio_charger->current_limit_map = devm_kmalloc_array(dev, + len / 2, sizeof(*gpio_charger->current_limit_map), GFP_KERNEL); + if (!gpio_charger->current_limit_map) + return -ENOMEM; + + gpio_charger->current_limit_map_size = len / 2; + + len = device_property_read_u32_array(dev, "charge-current-limit-mapping", + (u32*) gpio_charger->current_limit_map, len); + if (len < 0) + return len; + + for (i=0; i < gpio_charger->current_limit_map_size; i++) { + if (gpio_charger->current_limit_map[i].limit_ua > cur_limit) { + dev_err(dev, "invalid charge-current-limit-mapping\n"); + return -EINVAL; + } + + cur_limit = gpio_charger->current_limit_map[i].limit_ua; + } + + /* default to smallest current limitation for safety reasons */ + len = gpio_charger->current_limit_map_size - 1; + set_charge_current_limit(gpio_charger, + gpio_charger->current_limit_map[len].limit_ua); + + return 0; +} + +/* + * The entries will be overwritten by driver's probe routine depending + * on the available features. This list ensures, that the array is big + * enough for all optional features. + */ static enum power_supply_property gpio_charger_properties[] = { POWER_SUPPLY_PROP_ONLINE, - POWER_SUPPLY_PROP_STATUS /* Must always be last in the array. */ + POWER_SUPPLY_PROP_STATUS, + POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX, }; static int gpio_charger_probe(struct platform_device *pdev) @@ -128,6 +260,7 @@ static int gpio_charger_probe(struct platform_device *pdev) int charge_status_irq; unsigned long flags; int ret; + int num_props = 0; if (!pdata && !dev->of_node) { dev_err(dev, "No platform data\n"); @@ -137,18 +270,19 @@ static int gpio_charger_probe(struct platform_device *pdev) gpio_charger = devm_kzalloc(dev, sizeof(*gpio_charger), GFP_KERNEL); if (!gpio_charger) return -ENOMEM; + gpio_charger->dev = dev; /* * This will fetch a GPIO descriptor from device tree, ACPI or * boardfile descriptor tables. It's good to try this first. */ - gpio_charger->gpiod = devm_gpiod_get(dev, NULL, GPIOD_IN); + gpio_charger->gpiod = devm_gpiod_get_optional(dev, NULL, GPIOD_IN); /* * If this fails and we're not using device tree, try the * legacy platform data method. */ - if (IS_ERR(gpio_charger->gpiod) && !dev->of_node) { + if (!gpio_charger->gpiod && !dev->of_node) { /* Non-DT: use legacy GPIO numbers */ if (!gpio_is_valid(pdata->gpio)) { dev_err(dev, "Invalid gpio pin in pdata\n"); @@ -173,18 +307,38 @@ static int gpio_charger_probe(struct platform_device *pdev) return PTR_ERR(gpio_charger->gpiod); } + if (gpio_charger->gpiod && + num_props < ARRAY_SIZE(gpio_charger_properties)) { + gpio_charger_properties[num_props] = POWER_SUPPLY_PROP_ONLINE; + num_props++; + } + charge_status = devm_gpiod_get_optional(dev, "charge-status", GPIOD_IN); - gpio_charger->charge_status = charge_status; - if (IS_ERR(gpio_charger->charge_status)) - return PTR_ERR(gpio_charger->charge_status); + if (IS_ERR(charge_status)) + return PTR_ERR(charge_status); + if (charge_status && num_props < ARRAY_SIZE(gpio_charger_properties)) { + gpio_charger->charge_status = charge_status; + gpio_charger_properties[num_props] = POWER_SUPPLY_PROP_STATUS; + num_props++; + } + + ret = init_charge_current_limit(dev, gpio_charger); + if (ret < 0) + return ret; + if (gpio_charger->current_limit_map && + num_props < ARRAY_SIZE(gpio_charger_properties)) { + gpio_charger_properties[num_props] = + POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT_MAX; + num_props++; + } charger_desc = &gpio_charger->charger_desc; charger_desc->properties = gpio_charger_properties; - charger_desc->num_properties = ARRAY_SIZE(gpio_charger_properties); - /* Remove POWER_SUPPLY_PROP_STATUS from the supported properties. */ - if (!gpio_charger->charge_status) - charger_desc->num_properties -= 1; + charger_desc->num_properties = num_props; charger_desc->get_property = gpio_charger_get_property; + charger_desc->set_property = gpio_charger_set_property; + charger_desc->property_is_writeable = + gpio_charger_property_is_writeable; psy_cfg.of_node = dev->of_node; psy_cfg.drv_data = gpio_charger; @@ -269,6 +423,6 @@ static struct platform_driver gpio_charger_driver = { module_platform_driver(gpio_charger_driver); MODULE_AUTHOR("Lars-Peter Clausen "); -MODULE_DESCRIPTION("Driver for chargers which report their online status through a GPIO"); +MODULE_DESCRIPTION("Driver for chargers only communicating via GPIO(s)"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:gpio-charger");