1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2021~2022 NXP 4 * 5 * The driver exports a standard gpiochip interface 6 * to control the PIN resources on SCU domain. 7 */ 8 9 #include <linux/cleanup.h> 10 #include <linux/kernel.h> 11 #include <linux/module.h> 12 #include <linux/mutex.h> 13 #include <linux/gpio/driver.h> 14 #include <linux/platform_device.h> 15 #include <linux/firmware/imx/svc/rm.h> 16 #include <dt-bindings/firmware/imx/rsrc.h> 17 18 struct scu_gpio_priv { 19 struct gpio_chip chip; 20 struct mutex lock; 21 struct device *dev; 22 struct imx_sc_ipc *handle; 23 }; 24 25 static unsigned int scu_rsrc_arr[] = { 26 IMX_SC_R_BOARD_R0, 27 IMX_SC_R_BOARD_R1, 28 IMX_SC_R_BOARD_R2, 29 IMX_SC_R_BOARD_R3, 30 IMX_SC_R_BOARD_R4, 31 IMX_SC_R_BOARD_R5, 32 IMX_SC_R_BOARD_R6, 33 IMX_SC_R_BOARD_R7, 34 }; 35 36 static int imx_scu_gpio_get(struct gpio_chip *chip, unsigned int offset) 37 { 38 struct scu_gpio_priv *priv = gpiochip_get_data(chip); 39 int level; 40 int err; 41 42 scoped_guard(mutex, &priv->lock) { 43 /* to read PIN state via scu api */ 44 err = imx_sc_misc_get_control(priv->handle, 45 scu_rsrc_arr[offset], 0, &level); 46 } 47 if (err) { 48 dev_err(priv->dev, "SCU get failed: %d\n", err); 49 return err; 50 } 51 52 return level; 53 } 54 55 static int imx_scu_gpio_set(struct gpio_chip *chip, unsigned int offset, 56 int value) 57 { 58 struct scu_gpio_priv *priv = gpiochip_get_data(chip); 59 int err; 60 61 scoped_guard(mutex, &priv->lock) { 62 /* to set PIN output level via scu api */ 63 err = imx_sc_misc_set_control(priv->handle, 64 scu_rsrc_arr[offset], 0, value); 65 } 66 if (err) 67 dev_err(priv->dev, "SCU set (%d) failed: %d\n", 68 scu_rsrc_arr[offset], err); 69 70 return err; 71 } 72 73 static int imx_scu_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) 74 { 75 return GPIO_LINE_DIRECTION_OUT; 76 } 77 78 static int imx_scu_gpio_probe(struct platform_device *pdev) 79 { 80 struct device *dev = &pdev->dev; 81 struct scu_gpio_priv *priv; 82 struct gpio_chip *gc; 83 int ret; 84 85 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); 86 if (!priv) 87 return -ENOMEM; 88 89 ret = imx_scu_get_handle(&priv->handle); 90 if (ret) 91 return ret; 92 93 priv->dev = dev; 94 95 ret = devm_mutex_init(&pdev->dev, &priv->lock); 96 if (ret) 97 return ret; 98 99 gc = &priv->chip; 100 gc->base = -1; 101 gc->parent = dev; 102 gc->ngpio = ARRAY_SIZE(scu_rsrc_arr); 103 gc->label = dev_name(dev); 104 gc->get = imx_scu_gpio_get; 105 gc->set = imx_scu_gpio_set; 106 gc->get_direction = imx_scu_gpio_get_direction; 107 108 platform_set_drvdata(pdev, priv); 109 110 return devm_gpiochip_add_data(dev, gc, priv); 111 } 112 113 static const struct of_device_id imx_scu_gpio_dt_ids[] = { 114 { .compatible = "fsl,imx8qxp-sc-gpio" }, 115 { /* sentinel */ } 116 }; 117 118 static struct platform_driver imx_scu_gpio_driver = { 119 .driver = { 120 .name = "gpio-imx-scu", 121 .of_match_table = imx_scu_gpio_dt_ids, 122 }, 123 .probe = imx_scu_gpio_probe, 124 }; 125 126 static int __init _imx_scu_gpio_init(void) 127 { 128 return platform_driver_register(&imx_scu_gpio_driver); 129 } 130 131 subsys_initcall_sync(_imx_scu_gpio_init); 132 133 MODULE_AUTHOR("Shenwei Wang <shenwei.wang@nxp.com>"); 134 MODULE_DESCRIPTION("NXP GPIO over IMX SCU API"); 135