// SPDX-License-Identifier: GPL-2.0 /* * This file is part of STM32 DAC driver * * Copyright (C) 2017, STMicroelectronics - All Rights Reserved * Author: Fabrice Gasnier . * */ #include #include #include #include #include #include #include #include "stm32-dac-core.h" /** * struct stm32_dac_priv - stm32 DAC core private data * @pclk: peripheral clock common for all DACs * @vref: regulator reference * @common: Common data for all DAC instances */ struct stm32_dac_priv { struct clk *pclk; struct regulator *vref; struct stm32_dac_common common; }; /** * struct stm32_dac_cfg - DAC configuration * @has_hfsel: DAC has high frequency control */ struct stm32_dac_cfg { bool has_hfsel; }; static struct stm32_dac_priv *to_stm32_dac_priv(struct stm32_dac_common *com) { return container_of(com, struct stm32_dac_priv, common); } static const struct regmap_config stm32_dac_regmap_cfg = { .reg_bits = 32, .val_bits = 32, .reg_stride = sizeof(u32), .max_register = 0x3fc, }; static int stm32_dac_core_hw_start(struct device *dev) { struct stm32_dac_common *common = dev_get_drvdata(dev); struct stm32_dac_priv *priv = to_stm32_dac_priv(common); int ret; ret = regulator_enable(priv->vref); if (ret < 0) { dev_err(dev, "vref enable failed: %d\n", ret); return ret; } ret = clk_prepare_enable(priv->pclk); if (ret < 0) { dev_err(dev, "pclk enable failed: %d\n", ret); goto err_regulator_disable; } return 0; err_regulator_disable: regulator_disable(priv->vref); return ret; } static void stm32_dac_core_hw_stop(struct device *dev) { struct stm32_dac_common *common = dev_get_drvdata(dev); struct stm32_dac_priv *priv = to_stm32_dac_priv(common); clk_disable_unprepare(priv->pclk); regulator_disable(priv->vref); } static int stm32_dac_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; const struct stm32_dac_cfg *cfg; struct stm32_dac_priv *priv; struct regmap *regmap; struct resource *res; void __iomem *mmio; struct reset_control *rst; int ret; if (!dev->of_node) return -ENODEV; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; platform_set_drvdata(pdev, &priv->common); cfg = (const struct stm32_dac_cfg *) of_match_device(dev->driver->of_match_table, dev)->data; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); mmio = devm_ioremap_resource(dev, res); if (IS_ERR(mmio)) return PTR_ERR(mmio); regmap = devm_regmap_init_mmio_clk(dev, "pclk", mmio, &stm32_dac_regmap_cfg); if (IS_ERR(regmap)) return PTR_ERR(regmap); priv->common.regmap = regmap; priv->pclk = devm_clk_get(dev, "pclk"); if (IS_ERR(priv->pclk)) { ret = PTR_ERR(priv->pclk); dev_err(dev, "pclk get failed\n"); return ret; } priv->vref = devm_regulator_get(dev, "vref"); if (IS_ERR(priv->vref)) { ret = PTR_ERR(priv->vref); dev_err(dev, "vref get failed, %d\n", ret); return ret; } pm_runtime_get_noresume(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); ret = stm32_dac_core_hw_start(dev); if (ret) goto err_pm_stop; ret = regulator_get_voltage(priv->vref); if (ret < 0) { dev_err(dev, "vref get voltage failed, %d\n", ret); goto err_hw_stop; } priv->common.vref_mv = ret / 1000; dev_dbg(dev, "vref+=%dmV\n", priv->common.vref_mv); rst = devm_reset_control_get_optional_exclusive(dev, NULL); if (rst) { if (IS_ERR(rst)) { ret = dev_err_probe(dev, PTR_ERR(rst), "reset get failed\n"); goto err_hw_stop; } reset_control_assert(rst); udelay(2); reset_control_deassert(rst); } if (cfg && cfg->has_hfsel) { /* When clock speed is higher than 80MHz, set HFSEL */ priv->common.hfsel = (clk_get_rate(priv->pclk) > 80000000UL); ret = regmap_update_bits(regmap, STM32_DAC_CR, STM32H7_DAC_CR_HFSEL, priv->common.hfsel ? STM32H7_DAC_CR_HFSEL : 0); if (ret) goto err_hw_stop; } ret = of_platform_populate(pdev->dev.of_node, NULL, NULL, dev); if (ret < 0) { dev_err(dev, "failed to populate DT children\n"); goto err_hw_stop; } pm_runtime_put(dev); return 0; err_hw_stop: stm32_dac_core_hw_stop(dev); err_pm_stop: pm_runtime_disable(dev); pm_runtime_set_suspended(dev); pm_runtime_put_noidle(dev); return ret; } static int stm32_dac_remove(struct platform_device *pdev) { pm_runtime_get_sync(&pdev->dev); of_platform_depopulate(&pdev->dev); stm32_dac_core_hw_stop(&pdev->dev); pm_runtime_disable(&pdev->dev); pm_runtime_set_suspended(&pdev->dev); pm_runtime_put_noidle(&pdev->dev); return 0; } static int __maybe_unused stm32_dac_core_resume(struct device *dev) { struct stm32_dac_common *common = dev_get_drvdata(dev); struct stm32_dac_priv *priv = to_stm32_dac_priv(common); int ret; if (priv->common.hfsel) { /* restore hfsel (maybe lost under low power state) */ ret = regmap_update_bits(priv->common.regmap, STM32_DAC_CR, STM32H7_DAC_CR_HFSEL, STM32H7_DAC_CR_HFSEL); if (ret) return ret; } return pm_runtime_force_resume(dev); } static int __maybe_unused stm32_dac_core_runtime_suspend(struct device *dev) { stm32_dac_core_hw_stop(dev); return 0; } static int __maybe_unused stm32_dac_core_runtime_resume(struct device *dev) { return stm32_dac_core_hw_start(dev); } static const struct dev_pm_ops stm32_dac_core_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, stm32_dac_core_resume) SET_RUNTIME_PM_OPS(stm32_dac_core_runtime_suspend, stm32_dac_core_runtime_resume, NULL) }; static const struct stm32_dac_cfg stm32h7_dac_cfg = { .has_hfsel = true, }; static const struct of_device_id stm32_dac_of_match[] = { { .compatible = "st,stm32f4-dac-core", }, { .compatible = "st,stm32h7-dac-core", .data = (void *)&stm32h7_dac_cfg, }, {}, }; MODULE_DEVICE_TABLE(of, stm32_dac_of_match); static struct platform_driver stm32_dac_driver = { .probe = stm32_dac_probe, .remove = stm32_dac_remove, .driver = { .name = "stm32-dac-core", .of_match_table = stm32_dac_of_match, .pm = &stm32_dac_core_pm_ops, }, }; module_platform_driver(stm32_dac_driver); MODULE_AUTHOR("Fabrice Gasnier "); MODULE_DESCRIPTION("STMicroelectronics STM32 DAC core driver"); MODULE_LICENSE("GPL v2"); MODULE_ALIAS("platform:stm32-dac-core");