linux/drivers/pcmcia/omap_cf.c
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   1/*
   2 * omap_cf.c -- OMAP 16xx CompactFlash controller driver
   3 *
   4 * Copyright (c) 2005 David Brownell
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/kernel.h>
  14#include <linux/platform_device.h>
  15#include <linux/errno.h>
  16#include <linux/init.h>
  17#include <linux/delay.h>
  18#include <linux/interrupt.h>
  19#include <linux/slab.h>
  20
  21#include <pcmcia/ss.h>
  22
  23#include <mach/hardware.h>
  24#include <asm/io.h>
  25#include <asm/sizes.h>
  26
  27#include <mach/mux.h>
  28#include <plat/tc.h>
  29
  30
  31/* NOTE:  don't expect this to support many I/O cards.  The 16xx chips have
  32 * hard-wired timings to support Compact Flash memory cards; they won't work
  33 * with various other devices (like WLAN adapters) without some external
  34 * logic to help out.
  35 *
  36 * NOTE:  CF controller docs disagree with address space docs as to where
  37 * CF_BASE really lives; this is a doc erratum.
  38 */
  39#define CF_BASE 0xfffe2800
  40
  41/* status; read after IRQ */
  42#define CF_STATUS                       (CF_BASE + 0x00)
  43#       define  CF_STATUS_BAD_READ      (1 << 2)
  44#       define  CF_STATUS_BAD_WRITE     (1 << 1)
  45#       define  CF_STATUS_CARD_DETECT   (1 << 0)
  46
  47/* which chipselect (CS0..CS3) is used for CF (active low) */
  48#define CF_CFG                          (CF_BASE + 0x02)
  49
  50/* card reset */
  51#define CF_CONTROL                      (CF_BASE + 0x04)
  52#       define  CF_CONTROL_RESET        (1 << 0)
  53
  54#define omap_cf_present() (!(omap_readw(CF_STATUS) & CF_STATUS_CARD_DETECT))
  55
  56/*--------------------------------------------------------------------------*/
  57
  58static const char driver_name[] = "omap_cf";
  59
  60struct omap_cf_socket {
  61        struct pcmcia_socket    socket;
  62
  63        struct timer_list       timer;
  64        unsigned                present:1;
  65        unsigned                active:1;
  66
  67        struct platform_device  *pdev;
  68        unsigned long           phys_cf;
  69        u_int                   irq;
  70        struct resource         iomem;
  71};
  72
  73#define POLL_INTERVAL           (2 * HZ)
  74
  75/*--------------------------------------------------------------------------*/
  76
  77static int omap_cf_ss_init(struct pcmcia_socket *s)
  78{
  79        return 0;
  80}
  81
  82/* the timer is primarily to kick this socket's pccardd */
  83static void omap_cf_timer(unsigned long _cf)
  84{
  85        struct omap_cf_socket   *cf = (void *) _cf;
  86        unsigned                present = omap_cf_present();
  87
  88        if (present != cf->present) {
  89                cf->present = present;
  90                pr_debug("%s: card %s\n", driver_name,
  91                        present ? "present" : "gone");
  92                pcmcia_parse_events(&cf->socket, SS_DETECT);
  93        }
  94
  95        if (cf->active)
  96                mod_timer(&cf->timer, jiffies + POLL_INTERVAL);
  97}
  98
  99/* This irq handler prevents "irqNNN: nobody cared" messages as drivers
 100 * claim the card's IRQ.  It may also detect some card insertions, but
 101 * not removals; it can't always eliminate timer irqs.
 102 */
 103static irqreturn_t omap_cf_irq(int irq, void *_cf)
 104{
 105        omap_cf_timer((unsigned long)_cf);
 106        return IRQ_HANDLED;
 107}
 108
 109static int omap_cf_get_status(struct pcmcia_socket *s, u_int *sp)
 110{
 111        if (!sp)
 112                return -EINVAL;
 113
 114        /* NOTE CF is always 3VCARD */
 115        if (omap_cf_present()) {
 116                struct omap_cf_socket   *cf;
 117
 118                *sp = SS_READY | SS_DETECT | SS_POWERON | SS_3VCARD;
 119                cf = container_of(s, struct omap_cf_socket, socket);
 120                s->pcmcia_irq = 0;
 121                s->pci_irq = cf->irq;
 122        } else
 123                *sp = 0;
 124        return 0;
 125}
 126
 127static int
 128omap_cf_set_socket(struct pcmcia_socket *sock, struct socket_state_t *s)
 129{
 130        u16             control;
 131
 132        /* REVISIT some non-OSK boards may support power switching */
 133        switch (s->Vcc) {
 134        case 0:
 135        case 33:
 136                break;
 137        default:
 138                return -EINVAL;
 139        }
 140
 141        control = omap_readw(CF_CONTROL);
 142        if (s->flags & SS_RESET)
 143                omap_writew(CF_CONTROL_RESET, CF_CONTROL);
 144        else
 145                omap_writew(0, CF_CONTROL);
 146
 147        pr_debug("%s: Vcc %d, io_irq %d, flags %04x csc %04x\n",
 148                driver_name, s->Vcc, s->io_irq, s->flags, s->csc_mask);
 149
 150        return 0;
 151}
 152
 153static int omap_cf_ss_suspend(struct pcmcia_socket *s)
 154{
 155        pr_debug("%s: %s\n", driver_name, __func__);
 156        return omap_cf_set_socket(s, &dead_socket);
 157}
 158
 159/* regions are 2K each:  mem, attrib, io (and reserved-for-ide) */
 160
 161static int
 162omap_cf_set_io_map(struct pcmcia_socket *s, struct pccard_io_map *io)
 163{
 164        struct omap_cf_socket   *cf;
 165
 166        cf = container_of(s, struct omap_cf_socket, socket);
 167        io->flags &= MAP_ACTIVE|MAP_ATTRIB|MAP_16BIT;
 168        io->start = cf->phys_cf + SZ_4K;
 169        io->stop = io->start + SZ_2K - 1;
 170        return 0;
 171}
 172
 173static int
 174omap_cf_set_mem_map(struct pcmcia_socket *s, struct pccard_mem_map *map)
 175{
 176        struct omap_cf_socket   *cf;
 177
 178        if (map->card_start)
 179                return -EINVAL;
 180        cf = container_of(s, struct omap_cf_socket, socket);
 181        map->static_start = cf->phys_cf;
 182        map->flags &= MAP_ACTIVE|MAP_ATTRIB|MAP_16BIT;
 183        if (map->flags & MAP_ATTRIB)
 184                map->static_start += SZ_2K;
 185        return 0;
 186}
 187
 188static struct pccard_operations omap_cf_ops = {
 189        .init                   = omap_cf_ss_init,
 190        .suspend                = omap_cf_ss_suspend,
 191        .get_status             = omap_cf_get_status,
 192        .set_socket             = omap_cf_set_socket,
 193        .set_io_map             = omap_cf_set_io_map,
 194        .set_mem_map            = omap_cf_set_mem_map,
 195};
 196
 197/*--------------------------------------------------------------------------*/
 198
 199/*
 200 * NOTE:  right now the only board-specific platform_data is
 201 * "what chipselect is used".  Boards could want more.
 202 */
 203
 204static int __init omap_cf_probe(struct platform_device *pdev)
 205{
 206        unsigned                seg;
 207        struct omap_cf_socket   *cf;
 208        int                     irq;
 209        int                     status;
 210
 211        seg = (int) pdev->dev.platform_data;
 212        if (seg == 0 || seg > 3)
 213                return -ENODEV;
 214
 215        /* either CFLASH.IREQ (INT_1610_CF) or some GPIO */
 216        irq = platform_get_irq(pdev, 0);
 217        if (irq < 0)
 218                return -EINVAL;
 219
 220        cf = kzalloc(sizeof *cf, GFP_KERNEL);
 221        if (!cf)
 222                return -ENOMEM;
 223        init_timer(&cf->timer);
 224        cf->timer.function = omap_cf_timer;
 225        cf->timer.data = (unsigned long) cf;
 226
 227        cf->pdev = pdev;
 228        platform_set_drvdata(pdev, cf);
 229
 230        /* this primarily just shuts up irq handling noise */
 231        status = request_irq(irq, omap_cf_irq, IRQF_SHARED,
 232                        driver_name, cf);
 233        if (status < 0)
 234                goto fail0;
 235        cf->irq = irq;
 236        cf->socket.pci_irq = irq;
 237
 238        switch (seg) {
 239        /* NOTE: CS0 could be configured too ... */
 240        case 1:
 241                cf->phys_cf = OMAP_CS1_PHYS;
 242                break;
 243        case 2:
 244                cf->phys_cf = OMAP_CS2_PHYS;
 245                break;
 246        case 3:
 247                cf->phys_cf = omap_cs3_phys();
 248                break;
 249        default:
 250                goto  fail1;
 251        }
 252        cf->iomem.start = cf->phys_cf;
 253        cf->iomem.end = cf->iomem.end + SZ_8K - 1;
 254        cf->iomem.flags = IORESOURCE_MEM;
 255
 256        /* pcmcia layer only remaps "real" memory */
 257        cf->socket.io_offset = (unsigned long)
 258                        ioremap(cf->phys_cf + SZ_4K, SZ_2K);
 259        if (!cf->socket.io_offset)
 260                goto fail1;
 261
 262        if (!request_mem_region(cf->phys_cf, SZ_8K, driver_name))
 263                goto fail1;
 264
 265        /* NOTE:  CF conflicts with MMC1 */
 266        omap_cfg_reg(W11_1610_CF_CD1);
 267        omap_cfg_reg(P11_1610_CF_CD2);
 268        omap_cfg_reg(R11_1610_CF_IOIS16);
 269        omap_cfg_reg(V10_1610_CF_IREQ);
 270        omap_cfg_reg(W10_1610_CF_RESET);
 271
 272        omap_writew(~(1 << seg), CF_CFG);
 273
 274        pr_info("%s: cs%d on irq %d\n", driver_name, seg, irq);
 275
 276        /* NOTE:  better EMIFS setup might support more cards; but the
 277         * TRM only shows how to affect regular flash signals, not their
 278         * CF/PCMCIA variants...
 279         */
 280        pr_debug("%s: cs%d, previous ccs %08x acs %08x\n", driver_name,
 281                seg, omap_readl(EMIFS_CCS(seg)), omap_readl(EMIFS_ACS(seg)));
 282        omap_writel(0x0004a1b3, EMIFS_CCS(seg));        /* synch mode 4 etc */
 283        omap_writel(0x00000000, EMIFS_ACS(seg));        /* OE hold/setup */
 284
 285        /* CF uses armxor_ck, which is "always" available */
 286
 287        pr_debug("%s: sts %04x cfg %04x control %04x %s\n", driver_name,
 288                omap_readw(CF_STATUS), omap_readw(CF_CFG),
 289                omap_readw(CF_CONTROL),
 290                omap_cf_present() ? "present" : "(not present)");
 291
 292        cf->socket.owner = THIS_MODULE;
 293        cf->socket.dev.parent = &pdev->dev;
 294        cf->socket.ops = &omap_cf_ops;
 295        cf->socket.resource_ops = &pccard_static_ops;
 296        cf->socket.features = SS_CAP_PCCARD | SS_CAP_STATIC_MAP
 297                                | SS_CAP_MEM_ALIGN;
 298        cf->socket.map_size = SZ_2K;
 299        cf->socket.io[0].res = &cf->iomem;
 300
 301        status = pcmcia_register_socket(&cf->socket);
 302        if (status < 0)
 303                goto fail2;
 304
 305        cf->active = 1;
 306        mod_timer(&cf->timer, jiffies + POLL_INTERVAL);
 307        return 0;
 308
 309fail2:
 310        release_mem_region(cf->phys_cf, SZ_8K);
 311fail1:
 312        if (cf->socket.io_offset)
 313                iounmap((void __iomem *) cf->socket.io_offset);
 314        free_irq(irq, cf);
 315fail0:
 316        kfree(cf);
 317        return status;
 318}
 319
 320static int __exit omap_cf_remove(struct platform_device *pdev)
 321{
 322        struct omap_cf_socket *cf = platform_get_drvdata(pdev);
 323
 324        cf->active = 0;
 325        pcmcia_unregister_socket(&cf->socket);
 326        del_timer_sync(&cf->timer);
 327        iounmap((void __iomem *) cf->socket.io_offset);
 328        release_mem_region(cf->phys_cf, SZ_8K);
 329        free_irq(cf->irq, cf);
 330        kfree(cf);
 331        return 0;
 332}
 333
 334static struct platform_driver omap_cf_driver = {
 335        .driver = {
 336                .name   = (char *) driver_name,
 337                .owner  = THIS_MODULE,
 338        },
 339        .remove         = __exit_p(omap_cf_remove),
 340};
 341
 342static int __init omap_cf_init(void)
 343{
 344        if (cpu_is_omap16xx())
 345                return platform_driver_probe(&omap_cf_driver, omap_cf_probe);
 346        return -ENODEV;
 347}
 348
 349static void __exit omap_cf_exit(void)
 350{
 351        if (cpu_is_omap16xx())
 352                platform_driver_unregister(&omap_cf_driver);
 353}
 354
 355module_init(omap_cf_init);
 356module_exit(omap_cf_exit);
 357
 358MODULE_DESCRIPTION("OMAP CF Driver");
 359MODULE_LICENSE("GPL");
 360MODULE_ALIAS("platform:omap_cf");
 361
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