1 /* 2 * Copyright (c) 2011, NVIDIA Corporation. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along 15 * with this program; if not, write to the Free Software Foundation, Inc., 16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 17 */ 18 19 #include <linux/gpio.h> 20 #include <linux/init.h> 21 #include <linux/kernel.h> 22 #include <linux/module.h> 23 #include <linux/rfkill.h> 24 #include <linux/platform_device.h> 25 #include <linux/clk.h> 26 #include <linux/slab.h> 27 #include <linux/acpi.h> 28 #include <linux/acpi_gpio.h> 29 30 #include <linux/rfkill-gpio.h> 31 32 struct rfkill_gpio_data { 33 const char *name; 34 enum rfkill_type type; 35 int reset_gpio; 36 int shutdown_gpio; 37 38 struct rfkill *rfkill_dev; 39 char *reset_name; 40 char *shutdown_name; 41 struct clk *clk; 42 43 bool clk_enabled; 44 }; 45 46 static int rfkill_gpio_set_power(void *data, bool blocked) 47 { 48 struct rfkill_gpio_data *rfkill = data; 49 50 if (blocked) { 51 if (gpio_is_valid(rfkill->shutdown_gpio)) 52 gpio_set_value(rfkill->shutdown_gpio, 0); 53 if (gpio_is_valid(rfkill->reset_gpio)) 54 gpio_set_value(rfkill->reset_gpio, 0); 55 if (!IS_ERR(rfkill->clk) && rfkill->clk_enabled) 56 clk_disable(rfkill->clk); 57 } else { 58 if (!IS_ERR(rfkill->clk) && !rfkill->clk_enabled) 59 clk_enable(rfkill->clk); 60 if (gpio_is_valid(rfkill->reset_gpio)) 61 gpio_set_value(rfkill->reset_gpio, 1); 62 if (gpio_is_valid(rfkill->shutdown_gpio)) 63 gpio_set_value(rfkill->shutdown_gpio, 1); 64 } 65 66 rfkill->clk_enabled = blocked; 67 68 return 0; 69 } 70 71 static const struct rfkill_ops rfkill_gpio_ops = { 72 .set_block = rfkill_gpio_set_power, 73 }; 74 75 static int rfkill_gpio_acpi_probe(struct device *dev, 76 struct rfkill_gpio_data *rfkill) 77 { 78 const struct acpi_device_id *id; 79 80 id = acpi_match_device(dev->driver->acpi_match_table, dev); 81 if (!id) 82 return -ENODEV; 83 84 rfkill->name = dev_name(dev); 85 rfkill->type = (unsigned)id->driver_data; 86 rfkill->reset_gpio = acpi_get_gpio_by_index(dev, 0, NULL); 87 rfkill->shutdown_gpio = acpi_get_gpio_by_index(dev, 1, NULL); 88 89 return 0; 90 } 91 92 static int rfkill_gpio_probe(struct platform_device *pdev) 93 { 94 struct rfkill_gpio_platform_data *pdata = pdev->dev.platform_data; 95 struct rfkill_gpio_data *rfkill; 96 const char *clk_name = NULL; 97 int ret = 0; 98 int len = 0; 99 100 rfkill = devm_kzalloc(&pdev->dev, sizeof(*rfkill), GFP_KERNEL); 101 if (!rfkill) 102 return -ENOMEM; 103 104 if (ACPI_HANDLE(&pdev->dev)) { 105 ret = rfkill_gpio_acpi_probe(&pdev->dev, rfkill); 106 if (ret) 107 return ret; 108 } else if (pdata) { 109 clk_name = pdata->power_clk_name; 110 rfkill->name = pdata->name; 111 rfkill->type = pdata->type; 112 rfkill->reset_gpio = pdata->reset_gpio; 113 rfkill->shutdown_gpio = pdata->shutdown_gpio; 114 } else { 115 return -ENODEV; 116 } 117 118 /* make sure at-least one of the GPIO is defined and that 119 * a name is specified for this instance */ 120 if ((!gpio_is_valid(rfkill->reset_gpio) && 121 !gpio_is_valid(rfkill->shutdown_gpio)) || !rfkill->name) { 122 pr_warn("%s: invalid platform data\n", __func__); 123 return -EINVAL; 124 } 125 126 if (pdata && pdata->gpio_runtime_setup) { 127 ret = pdata->gpio_runtime_setup(pdev); 128 if (ret) { 129 pr_warn("%s: can't set up gpio\n", __func__); 130 return ret; 131 } 132 } 133 134 len = strlen(rfkill->name); 135 rfkill->reset_name = devm_kzalloc(&pdev->dev, len + 7, GFP_KERNEL); 136 if (!rfkill->reset_name) 137 return -ENOMEM; 138 139 rfkill->shutdown_name = devm_kzalloc(&pdev->dev, len + 10, GFP_KERNEL); 140 if (!rfkill->shutdown_name) 141 return -ENOMEM; 142 143 snprintf(rfkill->reset_name, len + 6 , "%s_reset", rfkill->name); 144 snprintf(rfkill->shutdown_name, len + 9, "%s_shutdown", rfkill->name); 145 146 rfkill->clk = devm_clk_get(&pdev->dev, clk_name); 147 148 if (gpio_is_valid(rfkill->reset_gpio)) { 149 ret = devm_gpio_request_one(&pdev->dev, rfkill->reset_gpio, 150 0, rfkill->reset_name); 151 if (ret) { 152 pr_warn("%s: failed to get reset gpio.\n", __func__); 153 return ret; 154 } 155 } 156 157 if (gpio_is_valid(rfkill->shutdown_gpio)) { 158 ret = devm_gpio_request_one(&pdev->dev, rfkill->shutdown_gpio, 159 0, rfkill->shutdown_name); 160 if (ret) { 161 pr_warn("%s: failed to get shutdown gpio.\n", __func__); 162 return ret; 163 } 164 } 165 166 rfkill->rfkill_dev = rfkill_alloc(rfkill->name, &pdev->dev, 167 rfkill->type, &rfkill_gpio_ops, 168 rfkill); 169 if (!rfkill->rfkill_dev) 170 return -ENOMEM; 171 172 ret = rfkill_register(rfkill->rfkill_dev); 173 if (ret < 0) 174 return ret; 175 176 platform_set_drvdata(pdev, rfkill); 177 178 dev_info(&pdev->dev, "%s device registered.\n", rfkill->name); 179 180 return 0; 181 } 182 183 static int rfkill_gpio_remove(struct platform_device *pdev) 184 { 185 struct rfkill_gpio_data *rfkill = platform_get_drvdata(pdev); 186 struct rfkill_gpio_platform_data *pdata = pdev->dev.platform_data; 187 188 if (pdata && pdata->gpio_runtime_close) 189 pdata->gpio_runtime_close(pdev); 190 rfkill_unregister(rfkill->rfkill_dev); 191 rfkill_destroy(rfkill->rfkill_dev); 192 193 return 0; 194 } 195 196 static const struct acpi_device_id rfkill_acpi_match[] = { 197 { "BCM4752", RFKILL_TYPE_GPS }, 198 { }, 199 }; 200 201 static struct platform_driver rfkill_gpio_driver = { 202 .probe = rfkill_gpio_probe, 203 .remove = rfkill_gpio_remove, 204 .driver = { 205 .name = "rfkill_gpio", 206 .owner = THIS_MODULE, 207 .acpi_match_table = ACPI_PTR(rfkill_acpi_match), 208 }, 209 }; 210 211 module_platform_driver(rfkill_gpio_driver); 212 213 MODULE_DESCRIPTION("gpio rfkill"); 214 MODULE_AUTHOR("NVIDIA"); 215 MODULE_LICENSE("GPL"); 216