123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272 |
- // SPDX-License-Identifier: GPL-2.0
- /*
- * This file is part of STM32 DAC driver
- *
- * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
- * Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
- *
- */
- #include <linux/clk.h>
- #include <linux/delay.h>
- #include <linux/module.h>
- #include <linux/of_platform.h>
- #include <linux/pm_runtime.h>
- #include <linux/regulator/consumer.h>
- #include <linux/reset.h>
- #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 <fabrice.gasnier@st.com>");
- MODULE_DESCRIPTION("STMicroelectronics STM32 DAC core driver");
- MODULE_LICENSE("GPL v2");
- MODULE_ALIAS("platform:stm32-dac-core");
|