Shenwei Wang | 0bd459dd | 2022-08-12 08:30:12 -0500 | [diff] [blame] | 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/module.h> |
| 10 | #include <linux/gpio/driver.h> |
| 11 | #include <linux/platform_device.h> |
| 12 | #include <linux/firmware/imx/svc/rm.h> |
| 13 | #include <dt-bindings/firmware/imx/rsrc.h> |
| 14 | |
| 15 | struct scu_gpio_priv { |
| 16 | struct gpio_chip chip; |
| 17 | struct mutex lock; |
| 18 | struct device *dev; |
| 19 | struct imx_sc_ipc *handle; |
| 20 | }; |
| 21 | |
| 22 | static unsigned int scu_rsrc_arr[] = { |
| 23 | IMX_SC_R_BOARD_R0, |
| 24 | IMX_SC_R_BOARD_R1, |
| 25 | IMX_SC_R_BOARD_R2, |
| 26 | IMX_SC_R_BOARD_R3, |
| 27 | IMX_SC_R_BOARD_R4, |
| 28 | IMX_SC_R_BOARD_R5, |
| 29 | IMX_SC_R_BOARD_R6, |
| 30 | IMX_SC_R_BOARD_R7, |
| 31 | }; |
| 32 | |
| 33 | static int imx_scu_gpio_get(struct gpio_chip *chip, unsigned int offset) |
| 34 | { |
| 35 | struct scu_gpio_priv *priv = gpiochip_get_data(chip); |
| 36 | int level; |
| 37 | int err; |
| 38 | |
| 39 | if (offset >= chip->ngpio) |
| 40 | return -EINVAL; |
| 41 | |
| 42 | mutex_lock(&priv->lock); |
| 43 | |
| 44 | /* to read PIN state via scu api */ |
| 45 | err = imx_sc_misc_get_control(priv->handle, |
| 46 | scu_rsrc_arr[offset], 0, &level); |
| 47 | mutex_unlock(&priv->lock); |
| 48 | |
| 49 | if (err) { |
| 50 | dev_err(priv->dev, "SCU get failed: %d\n", err); |
| 51 | return err; |
| 52 | } |
| 53 | |
| 54 | return level; |
| 55 | } |
| 56 | |
| 57 | static void imx_scu_gpio_set(struct gpio_chip *chip, unsigned int offset, int value) |
| 58 | { |
| 59 | struct scu_gpio_priv *priv = gpiochip_get_data(chip); |
| 60 | int err; |
| 61 | |
| 62 | if (offset >= chip->ngpio) |
| 63 | return; |
| 64 | |
| 65 | mutex_lock(&priv->lock); |
| 66 | |
| 67 | /* to set PIN output level via scu api */ |
| 68 | err = imx_sc_misc_set_control(priv->handle, |
| 69 | scu_rsrc_arr[offset], 0, value); |
| 70 | mutex_unlock(&priv->lock); |
| 71 | |
| 72 | if (err) |
| 73 | dev_err(priv->dev, "SCU set (%d) failed: %d\n", |
| 74 | scu_rsrc_arr[offset], err); |
| 75 | } |
| 76 | |
| 77 | static int imx_scu_gpio_get_direction(struct gpio_chip *chip, unsigned int offset) |
| 78 | { |
| 79 | if (offset >= chip->ngpio) |
| 80 | return -EINVAL; |
| 81 | |
| 82 | return GPIO_LINE_DIRECTION_OUT; |
| 83 | } |
| 84 | |
| 85 | static int imx_scu_gpio_probe(struct platform_device *pdev) |
| 86 | { |
| 87 | struct device *dev = &pdev->dev; |
| 88 | struct scu_gpio_priv *priv; |
| 89 | struct gpio_chip *gc; |
| 90 | int ret; |
| 91 | |
| 92 | priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); |
| 93 | if (!priv) |
| 94 | return -ENOMEM; |
| 95 | |
| 96 | ret = imx_scu_get_handle(&priv->handle); |
| 97 | if (ret) |
| 98 | return ret; |
| 99 | |
| 100 | priv->dev = dev; |
| 101 | mutex_init(&priv->lock); |
| 102 | |
| 103 | gc = &priv->chip; |
| 104 | gc->base = -1; |
| 105 | gc->parent = dev; |
| 106 | gc->ngpio = sizeof(scu_rsrc_arr)/sizeof(unsigned int); |
| 107 | gc->label = dev_name(dev); |
| 108 | gc->get = imx_scu_gpio_get; |
| 109 | gc->set = imx_scu_gpio_set; |
| 110 | gc->get_direction = imx_scu_gpio_get_direction; |
| 111 | |
| 112 | platform_set_drvdata(pdev, priv); |
| 113 | |
| 114 | return devm_gpiochip_add_data(dev, gc, priv); |
| 115 | } |
| 116 | |
| 117 | static const struct of_device_id imx_scu_gpio_dt_ids[] = { |
| 118 | { .compatible = "fsl,imx8qxp-sc-gpio" }, |
| 119 | { /* sentinel */ } |
| 120 | }; |
| 121 | |
| 122 | static struct platform_driver imx_scu_gpio_driver = { |
| 123 | .driver = { |
| 124 | .name = "gpio-imx-scu", |
| 125 | .of_match_table = imx_scu_gpio_dt_ids, |
| 126 | }, |
| 127 | .probe = imx_scu_gpio_probe, |
| 128 | }; |
| 129 | |
| 130 | static int __init _imx_scu_gpio_init(void) |
| 131 | { |
| 132 | return platform_driver_register(&imx_scu_gpio_driver); |
| 133 | } |
| 134 | |
| 135 | subsys_initcall_sync(_imx_scu_gpio_init); |
| 136 | |
| 137 | MODULE_AUTHOR("Shenwei Wang <shenwei.wang@nxp.com>"); |
| 138 | MODULE_DESCRIPTION("NXP GPIO over IMX SCU API"); |