From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- drivers/i2c/busses/i2c-elektor.c | 295 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 295 insertions(+) create mode 100644 drivers/i2c/busses/i2c-elektor.c (limited to 'drivers/i2c/busses/i2c-elektor.c') diff --git a/drivers/i2c/busses/i2c-elektor.c b/drivers/i2c/busses/i2c-elektor.c new file mode 100644 index 00000000000..0a7720000a0 --- /dev/null +++ b/drivers/i2c/busses/i2c-elektor.c @@ -0,0 +1,295 @@ +/* ------------------------------------------------------------------------- */ +/* i2c-elektor.c i2c-hw access for PCF8584 style isa bus adaptes */ +/* ------------------------------------------------------------------------- */ +/* Copyright (C) 1995-97 Simon G. Vogl + 1998-99 Hans Berglund + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ +/* ------------------------------------------------------------------------- */ + +/* With some changes from Kyösti Mälkki and even + Frodo Looijaard */ + +/* Partialy rewriten by Oleg I. Vdovikin for mmapped support of + for Alpha Processor Inc. UP-2000(+) boards */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include +#include + +#include "../algos/i2c-algo-pcf.h" + +#define DEFAULT_BASE 0x330 + +static int base; +static int irq; +static int clock = 0x1c; +static int own = 0x55; +static int mmapped; + +/* vdovikin: removed static struct i2c_pcf_isa gpi; code - + this module in real supports only one device, due to missing arguments + in some functions, called from the algo-pcf module. Sometimes it's + need to be rewriten - but for now just remove this for simpler reading */ + +static wait_queue_head_t pcf_wait; +static int pcf_pending; +static spinlock_t lock; + +/* ----- local functions ---------------------------------------------- */ + +static void pcf_isa_setbyte(void *data, int ctl, int val) +{ + int address = ctl ? (base + 1) : base; + + /* enable irq if any specified for serial operation */ + if (ctl && irq && (val & I2C_PCF_ESO)) { + val |= I2C_PCF_ENI; + } + + pr_debug("i2c-elektor: Write 0x%X 0x%02X\n", address, val & 255); + + switch (mmapped) { + case 0: /* regular I/O */ + outb(val, address); + break; + case 2: /* double mapped I/O needed for UP2000 board, + I don't know why this... */ + writeb(val, (void *)address); + /* fall */ + case 1: /* memory mapped I/O */ + writeb(val, (void *)address); + break; + } +} + +static int pcf_isa_getbyte(void *data, int ctl) +{ + int address = ctl ? (base + 1) : base; + int val = mmapped ? readb((void *)address) : inb(address); + + pr_debug("i2c-elektor: Read 0x%X 0x%02X\n", address, val); + + return (val); +} + +static int pcf_isa_getown(void *data) +{ + return (own); +} + + +static int pcf_isa_getclock(void *data) +{ + return (clock); +} + +static void pcf_isa_waitforpin(void) { + DEFINE_WAIT(wait); + int timeout = 2; + unsigned long flags; + + if (irq > 0) { + spin_lock_irqsave(&lock, flags); + if (pcf_pending == 0) { + spin_unlock_irqrestore(&lock, flags); + prepare_to_wait(&pcf_wait, &wait, TASK_INTERRUPTIBLE); + if (schedule_timeout(timeout*HZ)) { + spin_lock_irqsave(&lock, flags); + if (pcf_pending == 1) { + pcf_pending = 0; + } + spin_unlock_irqrestore(&lock, flags); + } + finish_wait(&pcf_wait, &wait); + } else { + pcf_pending = 0; + spin_unlock_irqrestore(&lock, flags); + } + } else { + udelay(100); + } +} + + +static irqreturn_t pcf_isa_handler(int this_irq, void *dev_id, struct pt_regs *regs) { + spin_lock(&lock); + pcf_pending = 1; + spin_unlock(&lock); + wake_up_interruptible(&pcf_wait); + return IRQ_HANDLED; +} + + +static int pcf_isa_init(void) +{ + spin_lock_init(&lock); + if (!mmapped) { + if (!request_region(base, 2, "i2c (isa bus adapter)")) { + printk(KERN_ERR + "i2c-elektor: requested I/O region (0x%X:2) " + "is in use.\n", base); + return -ENODEV; + } + } + if (irq > 0) { + if (request_irq(irq, pcf_isa_handler, 0, "PCF8584", NULL) < 0) { + printk(KERN_ERR "i2c-elektor: Request irq%d failed\n", irq); + irq = 0; + } else + enable_irq(irq); + } + return 0; +} + +/* ------------------------------------------------------------------------ + * Encapsulate the above functions in the correct operations structure. + * This is only done when more than one hardware adapter is supported. + */ +static struct i2c_algo_pcf_data pcf_isa_data = { + .setpcf = pcf_isa_setbyte, + .getpcf = pcf_isa_getbyte, + .getown = pcf_isa_getown, + .getclock = pcf_isa_getclock, + .waitforpin = pcf_isa_waitforpin, + .udelay = 10, + .mdelay = 10, + .timeout = 100, +}; + +static struct i2c_adapter pcf_isa_ops = { + .owner = THIS_MODULE, + .class = I2C_CLASS_HWMON, + .id = I2C_HW_P_ELEK, + .algo_data = &pcf_isa_data, + .name = "PCF8584 ISA adapter", +}; + +static int __init i2c_pcfisa_init(void) +{ +#ifdef __alpha__ + /* check to see we have memory mapped PCF8584 connected to the + Cypress cy82c693 PCI-ISA bridge as on UP2000 board */ + if (base == 0) { + struct pci_dev *cy693_dev; + + cy693_dev = pci_get_device(PCI_VENDOR_ID_CONTAQ, + PCI_DEVICE_ID_CONTAQ_82C693, NULL); + if (cy693_dev) { + char config; + /* yeap, we've found cypress, let's check config */ + if (!pci_read_config_byte(cy693_dev, 0x47, &config)) { + + pr_debug("i2c-elektor: found cy82c693, config register 0x47 = 0x%02x.\n", config); + + /* UP2000 board has this register set to 0xe1, + but the most significant bit as seems can be + reset during the proper initialisation + sequence if guys from API decides to do that + (so, we can even enable Tsunami Pchip + window for the upper 1 Gb) */ + + /* so just check for ROMCS at 0xe0000, + ROMCS enabled for writes + and external XD Bus buffer in use. */ + if ((config & 0x7f) == 0x61) { + /* seems to be UP2000 like board */ + base = 0xe0000; + /* I don't know why we need to + write twice */ + mmapped = 2; + /* UP2000 drives ISA with + 8.25 MHz (PCI/4) clock + (this can be read from cypress) */ + clock = I2C_PCF_CLK | I2C_PCF_TRNS90; + printk(KERN_INFO "i2c-elektor: found API UP2000 like board, will probe PCF8584 later.\n"); + } + } + pci_dev_put(cy693_dev); + } + } +#endif + + /* sanity checks for mmapped I/O */ + if (mmapped && base < 0xc8000) { + printk(KERN_ERR "i2c-elektor: incorrect base address (0x%0X) specified for mmapped I/O.\n", base); + return -ENODEV; + } + + printk(KERN_INFO "i2c-elektor: i2c pcf8584-isa adapter driver\n"); + + if (base == 0) { + base = DEFAULT_BASE; + } + + init_waitqueue_head(&pcf_wait); + if (pcf_isa_init()) + return -ENODEV; + if (i2c_pcf_add_bus(&pcf_isa_ops) < 0) + goto fail; + + printk(KERN_ERR "i2c-elektor: found device at %#x.\n", base); + + return 0; + + fail: + if (irq > 0) { + disable_irq(irq); + free_irq(irq, NULL); + } + + if (!mmapped) + release_region(base , 2); + return -ENODEV; +} + +static void i2c_pcfisa_exit(void) +{ + i2c_pcf_del_bus(&pcf_isa_ops); + + if (irq > 0) { + disable_irq(irq); + free_irq(irq, NULL); + } + + if (!mmapped) + release_region(base , 2); +} + +MODULE_AUTHOR("Hans Berglund "); +MODULE_DESCRIPTION("I2C-Bus adapter routines for PCF8584 ISA bus adapter"); +MODULE_LICENSE("GPL"); + +module_param(base, int, 0); +module_param(irq, int, 0); +module_param(clock, int, 0); +module_param(own, int, 0); +module_param(mmapped, int, 0); + +module_init(i2c_pcfisa_init); +module_exit(i2c_pcfisa_exit); -- cgit v1.2.3-18-g5258