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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Silicon Labs C2 port Linux support for Eurotech Duramar 21504 *5 * Copyright (c) 2008 Rodolfo Giometti <giometti@linux.it>6 * Copyright (c) 2008 Eurotech S.p.A. <info@eurotech.it>7 */8 9#include <linux/errno.h>10#include <linux/init.h>11#include <linux/kernel.h>12#include <linux/module.h>13#include <linux/delay.h>14#include <linux/io.h>15#include <linux/ioport.h>16#include <linux/c2port.h>17 18#define DATA_PORT 0x32519#define DIR_PORT 0x32620#define C2D (1 << 0)21#define C2CK (1 << 1)22 23static DEFINE_MUTEX(update_lock);24 25/*26 * C2 port operations27 */28 29static void duramar2150_c2port_access(struct c2port_device *dev, int status)30{31 u8 v;32 33 mutex_lock(&update_lock);34 35 v = inb(DIR_PORT);36 37 /* 0 = input, 1 = output */38 if (status)39 outb(v | (C2D | C2CK), DIR_PORT);40 else41 /* When access is "off" is important that both lines are set42 * as inputs or hi-impedance */43 outb(v & ~(C2D | C2CK), DIR_PORT);44 45 mutex_unlock(&update_lock);46}47 48static void duramar2150_c2port_c2d_dir(struct c2port_device *dev, int dir)49{50 u8 v;51 52 mutex_lock(&update_lock);53 54 v = inb(DIR_PORT);55 56 if (dir)57 outb(v & ~C2D, DIR_PORT);58 else59 outb(v | C2D, DIR_PORT);60 61 mutex_unlock(&update_lock);62}63 64static int duramar2150_c2port_c2d_get(struct c2port_device *dev)65{66 return inb(DATA_PORT) & C2D;67}68 69static void duramar2150_c2port_c2d_set(struct c2port_device *dev, int status)70{71 u8 v;72 73 mutex_lock(&update_lock);74 75 v = inb(DATA_PORT);76 77 if (status)78 outb(v | C2D, DATA_PORT);79 else80 outb(v & ~C2D, DATA_PORT);81 82 mutex_unlock(&update_lock);83}84 85static void duramar2150_c2port_c2ck_set(struct c2port_device *dev, int status)86{87 u8 v;88 89 mutex_lock(&update_lock);90 91 v = inb(DATA_PORT);92 93 if (status)94 outb(v | C2CK, DATA_PORT);95 else96 outb(v & ~C2CK, DATA_PORT);97 98 mutex_unlock(&update_lock);99}100 101static struct c2port_ops duramar2150_c2port_ops = {102 .block_size = 512, /* bytes */103 .blocks_num = 30, /* total flash size: 15360 bytes */104 105 .access = duramar2150_c2port_access,106 .c2d_dir = duramar2150_c2port_c2d_dir,107 .c2d_get = duramar2150_c2port_c2d_get,108 .c2d_set = duramar2150_c2port_c2d_set,109 .c2ck_set = duramar2150_c2port_c2ck_set,110};111 112static struct c2port_device *duramar2150_c2port_dev;113 114/*115 * Module stuff116 */117 118static int __init duramar2150_c2port_init(void)119{120 struct resource *res;121 int ret = 0;122 123 res = request_region(0x325, 2, "c2port");124 if (!res)125 return -EBUSY;126 127 duramar2150_c2port_dev = c2port_device_register("uc",128 &duramar2150_c2port_ops, NULL);129 if (IS_ERR(duramar2150_c2port_dev)) {130 ret = PTR_ERR(duramar2150_c2port_dev);131 goto free_region;132 }133 134 return 0;135 136free_region:137 release_region(0x325, 2);138 return ret;139}140 141static void __exit duramar2150_c2port_exit(void)142{143 /* Setup the GPIOs as input by default (access = 0) */144 duramar2150_c2port_access(duramar2150_c2port_dev, 0);145 146 c2port_device_unregister(duramar2150_c2port_dev);147 148 release_region(0x325, 2);149}150 151module_init(duramar2150_c2port_init);152module_exit(duramar2150_c2port_exit);153 154MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");155MODULE_DESCRIPTION("Silicon Labs C2 port Linux support for Duramar 2150");156MODULE_LICENSE("GPL");157