1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (c) 2011, NVIDIA Corporation. 4 */ 5 6 #include <linux/dmi.h> 7 #include <linux/init.h> 8 #include <linux/kernel.h> 9 #include <linux/module.h> 10 #include <linux/mod_devicetable.h> 11 #include <linux/rfkill.h> 12 #include <linux/of.h> 13 #include <linux/platform_device.h> 14 #include <linux/clk.h> 15 #include <linux/slab.h> 16 #include <linux/acpi.h> 17 #include <linux/gpio/consumer.h> 18 19 struct rfkill_gpio_data { 20 const char *name; 21 enum rfkill_type type; 22 struct gpio_desc *reset_gpio; 23 struct gpio_desc *shutdown_gpio; 24 25 struct rfkill *rfkill_dev; 26 struct clk *clk; 27 28 bool clk_enabled; 29 }; 30 31 static int rfkill_gpio_set_power(void *data, bool blocked) 32 { 33 struct rfkill_gpio_data *rfkill = data; 34 35 if (!blocked && !IS_ERR(rfkill->clk) && !rfkill->clk_enabled) 36 clk_enable(rfkill->clk); 37 38 gpiod_set_value_cansleep(rfkill->shutdown_gpio, !blocked); 39 gpiod_set_value_cansleep(rfkill->reset_gpio, !blocked); 40 41 if (blocked && !IS_ERR(rfkill->clk) && rfkill->clk_enabled) 42 clk_disable(rfkill->clk); 43 44 rfkill->clk_enabled = !blocked; 45 46 return 0; 47 } 48 49 static const struct rfkill_ops rfkill_gpio_ops = { 50 .set_block = rfkill_gpio_set_power, 51 }; 52 53 static const struct acpi_gpio_params reset_gpios = { 0, 0, false }; 54 static const struct acpi_gpio_params shutdown_gpios = { 1, 0, false }; 55 56 static const struct acpi_gpio_mapping acpi_rfkill_default_gpios[] = { 57 { "reset-gpios", &reset_gpios, 1 }, 58 { "shutdown-gpios", &shutdown_gpios, 1 }, 59 { }, 60 }; 61 62 static int rfkill_gpio_acpi_probe(struct device *dev, 63 struct rfkill_gpio_data *rfkill) 64 { 65 const struct acpi_device_id *id; 66 67 id = acpi_match_device(dev->driver->acpi_match_table, dev); 68 if (!id) 69 return -ENODEV; 70 71 rfkill->type = (unsigned)id->driver_data; 72 73 return devm_acpi_dev_add_driver_gpios(dev, acpi_rfkill_default_gpios); 74 } 75 76 /* List of DMI matches for devices on which rfkill-gpio should not load, 77 * to avoid firmware bugs. 78 */ 79 static const struct dmi_system_id rfkill_gpio_deny_table[] = { 80 { 81 /* Lenovo Yoga Tab 3 Pro YT3-X90, bogus "BCM4752" device in DSDT */ 82 .matches = { 83 DMI_MATCH(DMI_SYS_VENDOR, "Intel Corporation"), 84 DMI_MATCH(DMI_PRODUCT_VERSION, "Blade3-10A-001"), 85 }, 86 }, 87 { } 88 }; 89 90 static int rfkill_gpio_probe(struct platform_device *pdev) 91 { 92 struct rfkill_gpio_data *rfkill; 93 struct gpio_desc *gpio; 94 const char *name_property; 95 const char *type_property; 96 const char *type_name; 97 int ret; 98 99 if (dmi_check_system(rfkill_gpio_deny_table)) 100 return -ENODEV; 101 102 rfkill = devm_kzalloc(&pdev->dev, sizeof(*rfkill), GFP_KERNEL); 103 if (!rfkill) 104 return -ENOMEM; 105 106 if (dev_of_node(&pdev->dev)) { 107 name_property = "label"; 108 type_property = "radio-type"; 109 } else { 110 name_property = "name"; 111 type_property = "type"; 112 } 113 device_property_read_string(&pdev->dev, name_property, &rfkill->name); 114 device_property_read_string(&pdev->dev, type_property, &type_name); 115 116 if (!rfkill->name) 117 rfkill->name = dev_name(&pdev->dev); 118 119 rfkill->type = rfkill_find_type(type_name); 120 121 if (ACPI_HANDLE(&pdev->dev)) { 122 ret = rfkill_gpio_acpi_probe(&pdev->dev, rfkill); 123 if (ret) 124 return ret; 125 } 126 127 rfkill->clk = devm_clk_get(&pdev->dev, NULL); 128 129 gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_ASIS); 130 if (IS_ERR(gpio)) 131 return PTR_ERR(gpio); 132 133 rfkill->reset_gpio = gpio; 134 135 gpio = devm_gpiod_get_optional(&pdev->dev, "shutdown", GPIOD_ASIS); 136 if (IS_ERR(gpio)) 137 return PTR_ERR(gpio); 138 139 rfkill->shutdown_gpio = gpio; 140 141 /* Make sure at-least one GPIO is defined for this instance */ 142 if (!rfkill->reset_gpio && !rfkill->shutdown_gpio) { 143 dev_err(&pdev->dev, "invalid platform data\n"); 144 return -EINVAL; 145 } 146 147 ret = gpiod_direction_output(rfkill->reset_gpio, true); 148 if (ret) 149 return ret; 150 151 ret = gpiod_direction_output(rfkill->shutdown_gpio, true); 152 if (ret) 153 return ret; 154 155 rfkill->rfkill_dev = rfkill_alloc(rfkill->name, &pdev->dev, 156 rfkill->type, &rfkill_gpio_ops, 157 rfkill); 158 if (!rfkill->rfkill_dev) 159 return -ENOMEM; 160 161 ret = rfkill_register(rfkill->rfkill_dev); 162 if (ret < 0) 163 goto err_destroy; 164 165 platform_set_drvdata(pdev, rfkill); 166 167 dev_info(&pdev->dev, "%s device registered.\n", rfkill->name); 168 169 return 0; 170 171 err_destroy: 172 rfkill_destroy(rfkill->rfkill_dev); 173 174 return ret; 175 } 176 177 static void rfkill_gpio_remove(struct platform_device *pdev) 178 { 179 struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev); 180 181 rfkill_unregister(rfkill->rfkill_dev); 182 rfkill_destroy(rfkill->rfkill_dev); 183 } 184 185 #ifdef CONFIG_ACPI 186 static const struct acpi_device_id rfkill_acpi_match[] = { 187 { "BCM4752", RFKILL_TYPE_GPS }, 188 { "LNV4752", RFKILL_TYPE_GPS }, 189 { }, 190 }; 191 MODULE_DEVICE_TABLE(acpi, rfkill_acpi_match); 192 #endif 193 194 static const struct of_device_id rfkill_of_match[] __maybe_unused = { 195 { .compatible = "rfkill-gpio", }, 196 { }, 197 }; 198 MODULE_DEVICE_TABLE(of, rfkill_of_match); 199 200 static struct platform_driver rfkill_gpio_driver = { 201 .probe = rfkill_gpio_probe, 202 .remove_new = rfkill_gpio_remove, 203 .driver = { 204 .name = "rfkill_gpio", 205 .acpi_match_table = ACPI_PTR(rfkill_acpi_match), 206 .of_match_table = of_match_ptr(rfkill_of_match), 207 }, 208 }; 209 210 module_platform_driver(rfkill_gpio_driver); 211 212 MODULE_DESCRIPTION("gpio rfkill"); 213 MODULE_AUTHOR("NVIDIA"); 214 MODULE_LICENSE("GPL"); 215