pci/bt8xx/bttv-gpio.c

0001 // SPDX-License-Identifier: GPL-2.0-or-later
0002 /*
0003
0004     bttv-gpio.c  --  gpio sub drivers
0005
0006     sysfs-based sub driver interface for bttv
0007     mainly intended for gpio access
0008
0009
0010     Copyright (C) 1996,97,98 Ralph  Metzler (rjkm@thp.uni-koeln.de)
0011                & Marcus Metzler (mocm@thp.uni-koeln.de)
0012     (c) 1999-2003 Gerd Knorr <kraxel@bytesex.org>
0013
0014
0015 */
0016
0017 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
0018
0019 #include <linux/module.h>
0020 #include <linux/init.h>
0021 #include <linux/delay.h>
0022 #include <linux/device.h>
0023 #include <linux/slab.h>
0024 #include <asm/io.h>
0025
0026 #include "bttvp.h"
0027
0028 /* ----------------------------------------------------------------------- */
0029 /* internal: the bttv "bus"                                                */
0030
0031 static int bttv_sub_bus_match(struct device *dev, struct device_driver *drv)
0032 {
0033     struct bttv_sub_driver *sub = to_bttv_sub_drv(drv);
0034     int len = strlen(sub->wanted);
0035
0036     if (0 == strncmp(dev_name(dev), sub->wanted, len))
0037         return 1;
0038     return 0;
0039 }
0040
0041 static int bttv_sub_probe(struct device *dev)
0042 {
0043     struct bttv_sub_device *sdev = to_bttv_sub_dev(dev);
0044     struct bttv_sub_driver *sub = to_bttv_sub_drv(dev->driver);
0045
0046     return sub->probe ? sub->probe(sdev) : -ENODEV;
0047 }
0048
0049 static void bttv_sub_remove(struct device *dev)
0050 {
0051     struct bttv_sub_device *sdev = to_bttv_sub_dev(dev);
0052     struct bttv_sub_driver *sub = to_bttv_sub_drv(dev->driver);
0053
0054     if (sub->remove)
0055         sub->remove(sdev);
0056 }
0057
0058 struct bus_type bttv_sub_bus_type = {
0059     .name   = "bttv-sub",
0060     .match  = &bttv_sub_bus_match,
0061     .probe  = bttv_sub_probe,
0062     .remove = bttv_sub_remove,
0063 };
0064
0065 static void release_sub_device(struct device *dev)
0066 {
0067     struct bttv_sub_device *sub = to_bttv_sub_dev(dev);
0068     kfree(sub);
0069 }
0070
0071 int bttv_sub_add_device(struct bttv_core *core, char *name)
0072 {
0073     struct bttv_sub_device *sub;
0074     int err;
0075
0076     sub = kzalloc(sizeof(*sub),GFP_KERNEL);
0077     if (NULL == sub)
0078         return -ENOMEM;
0079
0080     sub->core        = core;
0081     sub->dev.parent  = &core->pci->dev;
0082     sub->dev.bus     = &bttv_sub_bus_type;
0083     sub->dev.release = release_sub_device;
0084     dev_set_name(&sub->dev, "%s%d", name, core->nr);
0085
0086     err = device_register(&sub->dev);
0087     if (0 != err) {
0088         put_device(&sub->dev);
0089         return err;
0090     }
0091     pr_info("%d: add subdevice \"%s\"\n", core->nr, dev_name(&sub->dev));
0092     list_add_tail(&sub->list,&core->subs);
0093     return 0;
0094 }
0095
0096 int bttv_sub_del_devices(struct bttv_core *core)
0097 {
0098     struct bttv_sub_device *sub, *save;
0099
0100     list_for_each_entry_safe(sub, save, &core->subs, list) {
0101         list_del(&sub->list);
0102         device_unregister(&sub->dev);
0103     }
0104     return 0;
0105 }
0106
0107 /* ----------------------------------------------------------------------- */
0108 /* external: sub-driver register/unregister                                */
0109
0110 int bttv_sub_register(struct bttv_sub_driver *sub, char *wanted)
0111 {
0112     sub->drv.bus = &bttv_sub_bus_type;
0113     snprintf(sub->wanted,sizeof(sub->wanted),"%s",wanted);
0114     return driver_register(&sub->drv);
0115 }
0116 EXPORT_SYMBOL(bttv_sub_register);
0117
0118 int bttv_sub_unregister(struct bttv_sub_driver *sub)
0119 {
0120     driver_unregister(&sub->drv);
0121     return 0;
0122 }
0123 EXPORT_SYMBOL(bttv_sub_unregister);
0124
0125 /* ----------------------------------------------------------------------- */
0126 /* external: gpio access functions                                         */
0127
0128 void bttv_gpio_inout(struct bttv_core *core, u32 mask, u32 outbits)
0129 {
0130     struct bttv *btv = container_of(core, struct bttv, c);
0131     unsigned long flags;
0132     u32 data;
0133
0134     spin_lock_irqsave(&btv->gpio_lock,flags);
0135     data = btread(BT848_GPIO_OUT_EN);
0136     data = data & ~mask;
0137     data = data | (mask & outbits);
0138     btwrite(data,BT848_GPIO_OUT_EN);
0139     spin_unlock_irqrestore(&btv->gpio_lock,flags);
0140 }
0141
0142 u32 bttv_gpio_read(struct bttv_core *core)
0143 {
0144     struct bttv *btv = container_of(core, struct bttv, c);
0145     u32 value;
0146
0147     value = btread(BT848_GPIO_DATA);
0148     return value;
0149 }
0150
0151 void bttv_gpio_write(struct bttv_core *core, u32 value)
0152 {
0153     struct bttv *btv = container_of(core, struct bttv, c);
0154
0155     btwrite(value,BT848_GPIO_DATA);
0156 }
0157
0158 void bttv_gpio_bits(struct bttv_core *core, u32 mask, u32 bits)
0159 {
0160     struct bttv *btv = container_of(core, struct bttv, c);
0161     unsigned long flags;
0162     u32 data;
0163
0164     spin_lock_irqsave(&btv->gpio_lock,flags);
0165     data = btread(BT848_GPIO_DATA);
0166     data = data & ~mask;
0167     data = data | (mask & bits);
0168     btwrite(data,BT848_GPIO_DATA);
0169     spin_unlock_irqrestore(&btv->gpio_lock,flags);
0170 }