// SPDX-License-Identifier: GPL-2.0-only /* * Copyright 2021~2022 NXP * * The driver exports a standard gpiochip interface * to control the PIN resources on SCU domain. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/gpio/driver.h> #include <linux/platform_device.h> #include <linux/firmware/imx/svc/rm.h> #include <dt-bindings/firmware/imx/rsrc.h> struct scu_gpio_priv { struct gpio_chip chip; struct mutex lock; struct device *dev; struct imx_sc_ipc *handle; }; static unsigned int scu_rsrc_arr[] = { IMX_SC_R_BOARD_R0, IMX_SC_R_BOARD_R1, IMX_SC_R_BOARD_R2, IMX_SC_R_BOARD_R3, IMX_SC_R_BOARD_R4, IMX_SC_R_BOARD_R5, IMX_SC_R_BOARD_R6, IMX_SC_R_BOARD_R7, }; static int imx_scu_gpio_get(struct gpio_chip *chip, unsigned int offset) { struct scu_gpio_priv *priv = gpiochip_get_data(chip); int level; int err; if (offset >= chip->ngpio) return -EINVAL; mutex_lock(&priv->lock); /* to read PIN state via scu api */ err = imx_sc_misc_get_control(priv->handle, scu_rsrc_arr[offset], 0, &level); mutex_unlock(&priv->lock); if (err) { dev_err(priv->dev, "SCU get failed: %d\n", err); return err; } return level; } static void imx_scu_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) { struct scu_gpio_priv *priv = gpiochip_get_data(chip); int err; if (offset >= chip->ngpio) return; mutex_lock(&priv->lock); /* to set PIN output level via scu api */ err = imx_sc_misc_set_control(priv->handle, scu_rsrc_arr[offset], 0, value); mutex_unlock(&priv->lock); if (err) dev_err(priv->dev, "SCU set (%d) failed: %d\n", scu_rsrc_arr[offset], err); } static int imx_scu_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) { if (offset >= chip->ngpio) return -EINVAL; return GPIO_LINE_DIRECTION_OUT; } static int imx_scu_gpio_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct scu_gpio_priv *priv; struct gpio_chip *gc; int ret; priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; ret = imx_scu_get_handle(&priv->handle); if (ret) return ret; priv->dev = dev; mutex_init(&priv->lock); gc = &priv->chip; gc->base = -1; gc->parent = dev; gc->ngpio = ARRAY_SIZE(scu_rsrc_arr); gc->label = dev_name(dev); gc->get = imx_scu_gpio_get; gc->set = imx_scu_gpio_set; gc->get_direction = imx_scu_gpio_get_direction; platform_set_drvdata(pdev, priv); return devm_gpiochip_add_data(dev, gc, priv); } static const struct of_device_id imx_scu_gpio_dt_ids[] = { { .compatible = "fsl,imx8qxp-sc-gpio" }, { /* sentinel */ } }; static struct platform_driver imx_scu_gpio_driver = { .driver = { .name = "gpio-imx-scu", .of_match_table = imx_scu_gpio_dt_ids, }, .probe = imx_scu_gpio_probe, }; static int __init _imx_scu_gpio_init(void) { return platform_driver_register(&imx_scu_gpio_driver); } subsys_initcall_sync(_imx_scu_gpio_init); MODULE_AUTHOR("Shenwei Wang <shenwei.wang@nxp.com>"); MODULE_DESCRIPTION("NXP GPIO over IMX SCU API");