1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 4 bttv-gpio.c -- gpio sub drivers 5 6 sysfs-based sub driver interface for bttv 7 mainly intended for gpio access 8 9 10 Copyright (C) 1996,97,98 Ralph Metzler (rjkm@thp.uni-koeln.de) 11 & Marcus Metzler (mocm@thp.uni-koeln.de) 12 (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org> 13 14 15 */ 16 17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 18 19 #include <linux/module.h> 20 #include <linux/init.h> 21 #include <linux/delay.h> 22 #include <linux/device.h> 23 #include <linux/slab.h> 24 #include <asm/io.h> 25 26 #include "bttvp.h" 27 28 /* ----------------------------------------------------------------------- */ 29 /* internal: the bttv "bus" */ 30 31 static int bttv_sub_bus_match(struct device *dev, struct device_driver *drv) 32 { 33 struct bttv_sub_driver *sub = to_bttv_sub_drv(drv); 34 int len = strlen(sub->wanted); 35 36 if (0 == strncmp(dev_name(dev), sub->wanted, len)) 37 return 1; 38 return 0; 39 } 40 41 static int bttv_sub_probe(struct device *dev) 42 { 43 struct bttv_sub_device *sdev = to_bttv_sub_dev(dev); 44 struct bttv_sub_driver *sub = to_bttv_sub_drv(dev->driver); 45 46 return sub->probe ? sub->probe(sdev) : -ENODEV; 47 } 48 49 static int bttv_sub_remove(struct device *dev) 50 { 51 struct bttv_sub_device *sdev = to_bttv_sub_dev(dev); 52 struct bttv_sub_driver *sub = to_bttv_sub_drv(dev->driver); 53 54 if (sub->remove) 55 sub->remove(sdev); 56 return 0; 57 } 58 59 struct bus_type bttv_sub_bus_type = { 60 .name = "bttv-sub", 61 .match = &bttv_sub_bus_match, 62 .probe = bttv_sub_probe, 63 .remove = bttv_sub_remove, 64 }; 65 66 static void release_sub_device(struct device *dev) 67 { 68 struct bttv_sub_device *sub = to_bttv_sub_dev(dev); 69 kfree(sub); 70 } 71 72 int bttv_sub_add_device(struct bttv_core *core, char *name) 73 { 74 struct bttv_sub_device *sub; 75 int err; 76 77 sub = kzalloc(sizeof(*sub),GFP_KERNEL); 78 if (NULL == sub) 79 return -ENOMEM; 80 81 sub->core = core; 82 sub->dev.parent = &core->pci->dev; 83 sub->dev.bus = &bttv_sub_bus_type; 84 sub->dev.release = release_sub_device; 85 dev_set_name(&sub->dev, "%s%d", name, core->nr); 86 87 err = device_register(&sub->dev); 88 if (0 != err) { 89 put_device(&sub->dev); 90 return err; 91 } 92 pr_info("%d: add subdevice \"%s\"\n", core->nr, dev_name(&sub->dev)); 93 list_add_tail(&sub->list,&core->subs); 94 return 0; 95 } 96 97 int bttv_sub_del_devices(struct bttv_core *core) 98 { 99 struct bttv_sub_device *sub, *save; 100 101 list_for_each_entry_safe(sub, save, &core->subs, list) { 102 list_del(&sub->list); 103 device_unregister(&sub->dev); 104 } 105 return 0; 106 } 107 108 /* ----------------------------------------------------------------------- */ 109 /* external: sub-driver register/unregister */ 110 111 int bttv_sub_register(struct bttv_sub_driver *sub, char *wanted) 112 { 113 sub->drv.bus = &bttv_sub_bus_type; 114 snprintf(sub->wanted,sizeof(sub->wanted),"%s",wanted); 115 return driver_register(&sub->drv); 116 } 117 EXPORT_SYMBOL(bttv_sub_register); 118 119 int bttv_sub_unregister(struct bttv_sub_driver *sub) 120 { 121 driver_unregister(&sub->drv); 122 return 0; 123 } 124 EXPORT_SYMBOL(bttv_sub_unregister); 125 126 /* ----------------------------------------------------------------------- */ 127 /* external: gpio access functions */ 128 129 void bttv_gpio_inout(struct bttv_core *core, u32 mask, u32 outbits) 130 { 131 struct bttv *btv = container_of(core, struct bttv, c); 132 unsigned long flags; 133 u32 data; 134 135 spin_lock_irqsave(&btv->gpio_lock,flags); 136 data = btread(BT848_GPIO_OUT_EN); 137 data = data & ~mask; 138 data = data | (mask & outbits); 139 btwrite(data,BT848_GPIO_OUT_EN); 140 spin_unlock_irqrestore(&btv->gpio_lock,flags); 141 } 142 143 u32 bttv_gpio_read(struct bttv_core *core) 144 { 145 struct bttv *btv = container_of(core, struct bttv, c); 146 u32 value; 147 148 value = btread(BT848_GPIO_DATA); 149 return value; 150 } 151 152 void bttv_gpio_write(struct bttv_core *core, u32 value) 153 { 154 struct bttv *btv = container_of(core, struct bttv, c); 155 156 btwrite(value,BT848_GPIO_DATA); 157 } 158 159 void bttv_gpio_bits(struct bttv_core *core, u32 mask, u32 bits) 160 { 161 struct bttv *btv = container_of(core, struct bttv, c); 162 unsigned long flags; 163 u32 data; 164 165 spin_lock_irqsave(&btv->gpio_lock,flags); 166 data = btread(BT848_GPIO_DATA); 167 data = data & ~mask; 168 data = data | (mask & bits); 169 btwrite(data,BT848_GPIO_DATA); 170 spin_unlock_irqrestore(&btv->gpio_lock,flags); 171 } 172