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 int ret = clk_enable(rfkill->clk); 37 38 if (ret) 39 return ret; 40 } 41 42 gpiod_set_value_cansleep(rfkill->shutdown_gpio, !blocked); 43 gpiod_set_value_cansleep(rfkill->reset_gpio, !blocked); 44 45 if (blocked && !IS_ERR(rfkill->clk) && rfkill->clk_enabled) 46 clk_disable(rfkill->clk); 47 48 rfkill->clk_enabled = !blocked; 49 50 return 0; 51 } 52 53 static const struct rfkill_ops rfkill_gpio_ops = { 54 .set_block = rfkill_gpio_set_power, 55 }; 56 57 static const struct acpi_gpio_params reset_gpios = { 0, 0, false }; 58 static const struct acpi_gpio_params shutdown_gpios = { 1, 0, false }; 59 60 static const struct acpi_gpio_mapping acpi_rfkill_default_gpios[] = { 61 { "reset-gpios", &reset_gpios, 1 }, 62 { "shutdown-gpios", &shutdown_gpios, 1 }, 63 { }, 64 }; 65 66 static int rfkill_gpio_acpi_probe(struct device *dev, 67 struct rfkill_gpio_data *rfkill) 68 { 69 const struct acpi_device_id *id; 70 71 id = acpi_match_device(dev->driver->acpi_match_table, dev); 72 if (!id) 73 return -ENODEV; 74 75 rfkill->type = (unsigned)id->driver_data; 76 77 return devm_acpi_dev_add_driver_gpios(dev, acpi_rfkill_default_gpios); 78 } 79 80 /* List of DMI matches for devices on which rfkill-gpio should not load, 81 * to avoid firmware bugs. 82 */ 83 static const struct dmi_system_id rfkill_gpio_deny_table[] = { 84 { 85 /* Lenovo Yoga Tab 3 Pro YT3-X90, bogus "BCM4752" device in DSDT */ 86 .matches = { 87 DMI_MATCH(DMI_SYS_VENDOR, "Intel Corporation"), 88 DMI_MATCH(DMI_PRODUCT_VERSION, "Blade3-10A-001"), 89 }, 90 }, 91 { } 92 }; 93 94 static int rfkill_gpio_probe(struct platform_device *pdev) 95 { 96 struct rfkill_gpio_data *rfkill; 97 struct gpio_desc *gpio; 98 const char *name_property; 99 const char *type_property; 100 const char *type_name; 101 int ret; 102 103 if (dmi_check_system(rfkill_gpio_deny_table)) 104 return -ENODEV; 105 106 rfkill = devm_kzalloc(&pdev->dev, sizeof(*rfkill), GFP_KERNEL); 107 if (!rfkill) 108 return -ENOMEM; 109 110 if (dev_of_node(&pdev->dev)) { 111 name_property = "label"; 112 type_property = "radio-type"; 113 } else { 114 name_property = "name"; 115 type_property = "type"; 116 } 117 device_property_read_string(&pdev->dev, name_property, &rfkill->name); 118 device_property_read_string(&pdev->dev, type_property, &type_name); 119 120 if (!rfkill->name) 121 rfkill->name = dev_name(&pdev->dev); 122 123 rfkill->type = rfkill_find_type(type_name); 124 125 if (ACPI_HANDLE(&pdev->dev)) { 126 ret = rfkill_gpio_acpi_probe(&pdev->dev, rfkill); 127 if (ret) 128 return ret; 129 } 130 131 rfkill->clk = devm_clk_get(&pdev->dev, NULL); 132 133 gpio = devm_gpiod_get_optional(&pdev->dev, "reset", GPIOD_ASIS); 134 if (IS_ERR(gpio)) 135 return PTR_ERR(gpio); 136 137 rfkill->reset_gpio = gpio; 138 139 gpio = devm_gpiod_get_optional(&pdev->dev, "shutdown", GPIOD_ASIS); 140 if (IS_ERR(gpio)) 141 return PTR_ERR(gpio); 142 143 rfkill->shutdown_gpio = gpio; 144 145 /* Make sure at-least one GPIO is defined for this instance */ 146 if (!rfkill->reset_gpio && !rfkill->shutdown_gpio) { 147 dev_err(&pdev->dev, "invalid platform data\n"); 148 return -EINVAL; 149 } 150 151 ret = gpiod_direction_output(rfkill->reset_gpio, true); 152 if (ret) 153 return ret; 154 155 ret = gpiod_direction_output(rfkill->shutdown_gpio, true); 156 if (ret) 157 return ret; 158 159 rfkill->rfkill_dev = rfkill_alloc(rfkill->name, &pdev->dev, 160 rfkill->type, &rfkill_gpio_ops, 161 rfkill); 162 if (!rfkill->rfkill_dev) 163 return -ENOMEM; 164 165 ret = rfkill_register(rfkill->rfkill_dev); 166 if (ret < 0) 167 goto err_destroy; 168 169 platform_set_drvdata(pdev, rfkill); 170 171 dev_info(&pdev->dev, "%s device registered.\n", rfkill->name); 172 173 return 0; 174 175 err_destroy: 176 rfkill_destroy(rfkill->rfkill_dev); 177 178 return ret; 179 } 180 181 static void rfkill_gpio_remove(struct platform_device *pdev) 182 { 183 struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev); 184 185 rfkill_unregister(rfkill->rfkill_dev); 186 rfkill_destroy(rfkill->rfkill_dev); 187 } 188 189 #ifdef CONFIG_ACPI 190 static const struct acpi_device_id rfkill_acpi_match[] = { 191 { "BCM4752", RFKILL_TYPE_GPS }, 192 { "LNV4752", RFKILL_TYPE_GPS }, 193 { }, 194 }; 195 MODULE_DEVICE_TABLE(acpi, rfkill_acpi_match); 196 #endif 197 198 static const struct of_device_id rfkill_of_match[] __maybe_unused = { 199 { .compatible = "rfkill-gpio", }, 200 { }, 201 }; 202 MODULE_DEVICE_TABLE(of, rfkill_of_match); 203 204 static struct platform_driver rfkill_gpio_driver = { 205 .probe = rfkill_gpio_probe, 206 .remove_new = rfkill_gpio_remove, 207 .driver = { 208 .name = "rfkill_gpio", 209 .acpi_match_table = ACPI_PTR(rfkill_acpi_match), 210 .of_match_table = of_match_ptr(rfkill_of_match), 211 }, 212 }; 213 214 module_platform_driver(rfkill_gpio_driver); 215 216 MODULE_DESCRIPTION("gpio rfkill"); 217 MODULE_AUTHOR("NVIDIA"); 218 MODULE_LICENSE("GPL"); 219