// SPDX-License-Identifier: GPL-2.0 // Copyright (C) STMicroelectronics 2019 // Authors: Gabriel Fernandez <gabriel.fernandez@st.com> // Pascal Paillet <p.paillet@st.com>. #include <linux/io.h> #include <linux/iopoll.h> #include <linux/module.h> #include <linux/of_address.h> #include <linux/of_device.h> #include <linux/platform_device.h> #include <linux/regulator/driver.h> #include <linux/regulator/of_regulator.h> /* * Registers description */ #define REG_PWR_CR3 0x0C #define USB_3_3_EN BIT(24) #define USB_3_3_RDY BIT(26) #define REG_1_8_EN BIT(28) #define REG_1_8_RDY BIT(29) #define REG_1_1_EN BIT(30) #define REG_1_1_RDY BIT(31) /* list of supported regulators */ enum { PWR_REG11, PWR_REG18, PWR_USB33, STM32PWR_REG_NUM_REGS }; static u32 ready_mask_table[STM32PWR_REG_NUM_REGS] = { [PWR_REG11] = REG_1_1_RDY, [PWR_REG18] = REG_1_8_RDY, [PWR_USB33] = USB_3_3_RDY, }; struct stm32_pwr_reg { void __iomem *base; u32 ready_mask; }; static int stm32_pwr_reg_is_ready(struct regulator_dev *rdev) { struct stm32_pwr_reg *priv = rdev_get_drvdata(rdev); u32 val; val = readl_relaxed(priv->base + REG_PWR_CR3); return (val & priv->ready_mask); } static int stm32_pwr_reg_is_enabled(struct regulator_dev *rdev) { struct stm32_pwr_reg *priv = rdev_get_drvdata(rdev); u32 val; val = readl_relaxed(priv->base + REG_PWR_CR3); return (val & rdev->desc->enable_mask); } static int stm32_pwr_reg_enable(struct regulator_dev *rdev) { struct stm32_pwr_reg *priv = rdev_get_drvdata(rdev); int ret; u32 val; val = readl_relaxed(priv->base + REG_PWR_CR3); val |= rdev->desc->enable_mask; writel_relaxed(val, priv->base + REG_PWR_CR3); /* use an arbitrary timeout of 20ms */ ret = readx_poll_timeout(stm32_pwr_reg_is_ready, rdev, val, val, 100, 20 * 1000); if (ret) dev_err(&rdev->dev, "regulator enable timed out!\n"); return ret; } static int stm32_pwr_reg_disable(struct regulator_dev *rdev) { struct stm32_pwr_reg *priv = rdev_get_drvdata(rdev); int ret; u32 val; val = readl_relaxed(priv->base + REG_PWR_CR3); val &= ~rdev->desc->enable_mask; writel_relaxed(val, priv->base + REG_PWR_CR3); /* use an arbitrary timeout of 20ms */ ret = readx_poll_timeout(stm32_pwr_reg_is_ready, rdev, val, !val, 100, 20 * 1000); if (ret) dev_err(&rdev->dev, "regulator disable timed out!\n"); return ret; } static const struct regulator_ops stm32_pwr_reg_ops = { .enable = stm32_pwr_reg_enable, .disable = stm32_pwr_reg_disable, .is_enabled = stm32_pwr_reg_is_enabled, }; #define PWR_REG(_id, _name, _volt, _en, _supply) \ [_id] = { \ .id = _id, \ .name = _name, \ .of_match = of_match_ptr(_name), \ .n_voltages = 1, \ .type = REGULATOR_VOLTAGE, \ .fixed_uV = _volt, \ .ops = &stm32_pwr_reg_ops, \ .enable_mask = _en, \ .owner = THIS_MODULE, \ .supply_name = _supply, \ } \ static const struct regulator_desc stm32_pwr_desc[] = { PWR_REG(PWR_REG11, "reg11", 1100000, REG_1_1_EN, "vdd"), PWR_REG(PWR_REG18, "reg18", 1800000, REG_1_8_EN, "vdd"), PWR_REG(PWR_USB33, "usb33", 3300000, USB_3_3_EN, "vdd_3v3_usbfs"), }; static int stm32_pwr_regulator_probe(struct platform_device *pdev) { struct device_node *np = pdev->dev.of_node; struct stm32_pwr_reg *priv; void __iomem *base; struct regulator_dev *rdev; struct regulator_config config = { }; int i, ret = 0; base = of_iomap(np, 0); if (!base) { dev_err(&pdev->dev, "Unable to map IO memory\n"); return -ENOMEM; } config.dev = &pdev->dev; for (i = 0; i < STM32PWR_REG_NUM_REGS; i++) { priv = devm_kzalloc(&pdev->dev, sizeof(struct stm32_pwr_reg), GFP_KERNEL); if (!priv) return -ENOMEM; priv->base = base; priv->ready_mask = ready_mask_table[i]; config.driver_data = priv; rdev = devm_regulator_register(&pdev->dev, &stm32_pwr_desc[i], &config); if (IS_ERR(rdev)) { ret = PTR_ERR(rdev); dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret); break; } } return ret; } static const struct of_device_id stm32_pwr_of_match[] = { { .compatible = "st,stm32mp1,pwr-reg", }, {}, }; MODULE_DEVICE_TABLE(of, stm32_pwr_of_match); static struct platform_driver stm32_pwr_driver = { .probe = stm32_pwr_regulator_probe, .driver = { .name = "stm32-pwr-regulator", .of_match_table = of_match_ptr(stm32_pwr_of_match), }, }; module_platform_driver(stm32_pwr_driver); MODULE_DESCRIPTION("STM32MP1 PWR voltage regulator driver"); MODULE_AUTHOR("Pascal Paillet <p.paillet@st.com>"); MODULE_LICENSE("GPL v2");