[PATCH] pcmcia: AT91RM9200 Compact Flash driver

This patch adds support for the Compact Flash controller integrated in
the Atmel AT91RM9200 processor.

Signed-off-by: Andrew Victor <andrew@sanpeople.com
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>

1 files changed, 365 insertions, 0 deletions

diff --git a/drivers/pcmcia/at91_cf.c b/drivers/pcmcia/at91_cf.c
new file mode 100644
index 000000000000..67cc5f7d0c90
--- /dev/null
+++ b/drivers/pcmcia/at91_cf.c
@@ -0,0 +1,365 @@
+/*
+ * at91_cf.c -- AT91 CompactFlash controller driver
+ *
+ * Copyright (C) 2005 David Brownell
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/platform_device.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+
+#include <pcmcia/ss.h>
+
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/sizes.h>
+
+#include <asm/arch/at91rm9200.h>
+#include <asm/arch/board.h>
+#include <asm/arch/gpio.h>
+
+
+#define CF_SIZE         0x30000000      /* CS5+CS6: unavailable */
+
+/*
+ * A0..A10 work in each range; A23 indicates I/O space;  A25 is CFRNW;
+ * some other bit in {A24,A22..A11} is nREG to flag memory access
+ * (vs attributes).  So more than 2KB/region would just be waste.
+ */
+#define CF_ATTR_PHYS    (AT91_CF_BASE)
+#define CF_IO_PHYS      (AT91_CF_BASE  + (1 << 23))
+#define CF_MEM_PHYS     (AT91_CF_BASE  + 0x017ff800)
+
+/*--------------------------------------------------------------------------*/
+
+static const char driver_name[] = "at91_cf";
+
+struct at91_cf_socket {
+        struct pcmcia_socket    socket;
+
+        unsigned                present:1;
+
+        struct platform_device  *pdev;
+        struct at91_cf_data     *board;
+};
+
+#define SZ_2K                   (2 * SZ_1K)
+
+static inline int at91_cf_present(struct at91_cf_socket *cf)
+{
+        return !at91_get_gpio_value(cf->board->det_pin);
+}
+
+/*--------------------------------------------------------------------------*/
+
+static int at91_cf_ss_init(struct pcmcia_socket *s)
+{
+        return 0;
+}
+
+static irqreturn_t at91_cf_irq(int irq, void *_cf, struct pt_regs *r)
+{
+        struct at91_cf_socket   *cf = (struct at91_cf_socket *) _cf;
+
+        if (irq == cf->board->det_pin) {
+                unsigned present = at91_cf_present(cf);
+
+                /* kick pccard as needed */
+                if (present != cf->present) {
+                        cf->present = present;
+                        pr_debug("%s: card %s\n", driver_name, present ? "present" : "gone");
+                        pcmcia_parse_events(&cf->socket, SS_DETECT);
+                }
+        }
+
+        return IRQ_HANDLED;
+}
+
+static int at91_cf_get_status(struct pcmcia_socket *s, u_int *sp)
+{
+        struct at91_cf_socket   *cf;
+
+        if (!sp)
+                return -EINVAL;
+
+        cf = container_of(s, struct at91_cf_socket, socket);
+
+        /* NOTE: we assume 3VCARD, not XVCARD...  */
+        if (at91_cf_present(cf)) {
+                int rdy = cf->board->irq_pin;   /* RDY/nIRQ */
+                int vcc = cf->board->vcc_pin;
+
+                *sp = SS_DETECT | SS_3VCARD;
+                if (!rdy || at91_get_gpio_value(rdy))
+                        *sp |= SS_READY;
+                if (!vcc || at91_get_gpio_value(vcc))
+                        *sp |= SS_POWERON;
+        } else
+                *sp = 0;
+
+        return 0;
+}
+
+static int at91_cf_set_socket(struct pcmcia_socket *sock, struct socket_state_t *s)
+{
+        struct at91_cf_socket   *cf;
+
+        cf = container_of(sock, struct at91_cf_socket, socket);
+
+        /* switch Vcc if needed and possible */
+        if (cf->board->vcc_pin) {
+                switch (s->Vcc) {
+                        case 0:
+                                at91_set_gpio_value(cf->board->vcc_pin, 0);
+                                break;
+                        case 33:
+                                at91_set_gpio_value(cf->board->vcc_pin, 1);
+                                break;
+                        default:
+                                return -EINVAL;
+                }
+        }
+
+        /* toggle reset if needed */
+        at91_set_gpio_value(cf->board->rst_pin, s->flags & SS_RESET);
+
+        pr_debug("%s: Vcc %d, io_irq %d, flags %04x csc %04x\n",
+                driver_name, s->Vcc, s->io_irq, s->flags, s->csc_mask);
+
+        return 0;
+}
+
+static int at91_cf_ss_suspend(struct pcmcia_socket *s)
+{
+        return at91_cf_set_socket(s, &dead_socket);
+}
+
+/* we already mapped the I/O region */
+static int at91_cf_set_io_map(struct pcmcia_socket *s, struct pccard_io_map *io)
+{
+        struct at91_cf_socket   *cf;
+        u32                     csr;
+
+        cf = container_of(s, struct at91_cf_socket, socket);
+        io->flags &= (MAP_ACTIVE | MAP_16BIT | MAP_AUTOSZ);
+
+        /*
+         * Use 16 bit accesses unless/until we need 8-bit i/o space.
+         * Always set CSR4 ... PCMCIA won't always unmap things.
+         */
+        csr = at91_sys_read(AT91_SMC_CSR(4)) & ~AT91_SMC_DBW;
+
+        /*
+         * NOTE: this CF controller ignores IOIS16, so we can't really do
+         * MAP_AUTOSZ.  The 16bit mode allows single byte access on either
+         * D0-D7 (even addr) or D8-D15 (odd), so it's close enough for many
+         * purposes (and handles ide-cs).
+         *
+         * The 8bit mode is needed for odd byte access on D0-D7.  It seems
+         * some cards only like that way to get at the odd byte, despite
+         * CF 3.0 spec table 35 also giving the D8-D15 option.
+         */
+        if (!(io->flags & (MAP_16BIT|MAP_AUTOSZ))) {
+                csr |= AT91_SMC_DBW_8;
+                pr_debug("%s: 8bit i/o bus\n", driver_name);
+        } else {
+                csr |= AT91_SMC_DBW_16;
+                pr_debug("%s: 16bit i/o bus\n", driver_name);
+        }
+        at91_sys_write(AT91_SMC_CSR(4), csr);
+
+        io->start = cf->socket.io_offset;
+        io->stop = io->start + SZ_2K - 1;
+
+        return 0;
+}
+
+/* pcmcia layer maps/unmaps mem regions */
+static int at91_cf_set_mem_map(struct pcmcia_socket *s, struct pccard_mem_map *map)
+{
+        struct at91_cf_socket   *cf;
+
+        if (map->card_start)
+                return -EINVAL;
+
+        cf = container_of(s, struct at91_cf_socket, socket);
+
+        map->flags &= MAP_ACTIVE|MAP_ATTRIB|MAP_16BIT;
+        if (map->flags & MAP_ATTRIB)
+                map->static_start = CF_ATTR_PHYS;
+        else
+                map->static_start = CF_MEM_PHYS;
+
+        return 0;
+}
+
+static struct pccard_operations at91_cf_ops = {
+        .init                   = at91_cf_ss_init,
+        .suspend                = at91_cf_ss_suspend,
+        .get_status             = at91_cf_get_status,
+        .set_socket             = at91_cf_set_socket,
+        .set_io_map             = at91_cf_set_io_map,
+        .set_mem_map            = at91_cf_set_mem_map,
+};
+
+/*--------------------------------------------------------------------------*/
+
+static int __init at91_cf_probe(struct device *dev)
+{
+        struct at91_cf_socket   *cf;
+        struct at91_cf_data     *board = dev->platform_data;
+        struct platform_device  *pdev = to_platform_device(dev);
+        unsigned int            csa;
+        int                     status;
+
+        if (!board || !board->det_pin || !board->rst_pin)
+                return -ENODEV;
+
+        cf = kcalloc(1, sizeof *cf, GFP_KERNEL);
+        if (!cf)
+                return -ENOMEM;
+
+        cf->board = board;
+        cf->pdev = pdev;
+        dev_set_drvdata(dev, cf);
+
+        /* CF takes over CS4, CS5, CS6 */
+        csa = at91_sys_read(AT91_EBI_CSA);
+        at91_sys_write(AT91_EBI_CSA, csa | AT91_EBI_CS4A_SMC_COMPACTFLASH);
+
+        /* force poweron defaults for these pins ... */
+        (void) at91_set_A_periph(AT91_PIN_PC9, 0);      /* A25/CFRNW */
+        (void) at91_set_A_periph(AT91_PIN_PC10, 0);     /* NCS4/CFCS */
+        (void) at91_set_A_periph(AT91_PIN_PC11, 0);     /* NCS5/CFCE1 */
+        (void) at91_set_A_periph(AT91_PIN_PC12, 0);     /* NCS6/CFCE2 */
+
+        /* nWAIT is _not_ a default setting */
+        (void) at91_set_A_periph(AT91_PIN_PC6, 1);      /*  nWAIT */
+
+        /*
+         * Static memory controller timing adjustments.
+         * REVISIT:  these timings are in terms of MCK cycles, so
+         * when MCK changes (cpufreq etc) so must these values...
+         */
+        at91_sys_write(AT91_SMC_CSR(4), AT91_SMC_ACSS_STD | AT91_SMC_DBW_16 | AT91_SMC_BAT | AT91_SMC_WSEN
+                                | AT91_SMC_NWS_(32)             /* wait states */
+                                | AT91_SMC_RWSETUP_(6)          /* setup time */
+                                | AT91_SMC_RWHOLD_(4)           /* hold time */
+        );
+
+        /* must be a GPIO; ergo must trigger on both edges */
+        status = request_irq(board->det_pin, at91_cf_irq,
+                        SA_SAMPLE_RANDOM, driver_name, cf);
+        if (status < 0)
+                goto fail0;
+
+        /*
+         * The card driver will request this irq later as needed.
+         * but it causes lots of "irqNN: nobody cared" messages
+         * unless we report that we handle everything (sigh).
+         * (Note:  DK board doesn't wire the IRQ pin...)
+         */
+        if (board->irq_pin) {
+                status = request_irq(board->irq_pin, at91_cf_irq,
+                                SA_SHIRQ, driver_name, cf);
+                if (status < 0)
+                        goto fail0a;
+                cf->socket.pci_irq = board->irq_pin;
+        }
+        else
+                cf->socket.pci_irq = NR_IRQS + 1;
+
+        /* pcmcia layer only remaps "real" memory not iospace */
+        cf->socket.io_offset = (unsigned long) ioremap(CF_IO_PHYS, SZ_2K);
+        if (!cf->socket.io_offset)
+                goto fail1;
+
+        /* reserve CS4, CS5, and CS6 regions; but use just CS4 */
+        if (!request_mem_region(AT91_CF_BASE, CF_SIZE, driver_name))
+                goto fail1;
+
+        pr_info("%s: irqs det #%d, io #%d\n", driver_name,
+                board->det_pin, board->irq_pin);
+
+        cf->socket.owner = THIS_MODULE;
+        cf->socket.dev.dev = dev;
+        cf->socket.ops = &at91_cf_ops;
+        cf->socket.resource_ops = &pccard_static_ops;
+        cf->socket.features = SS_CAP_PCCARD | SS_CAP_STATIC_MAP
+                                | SS_CAP_MEM_ALIGN;
+        cf->socket.map_size = SZ_2K;
+        cf->socket.io[0].NumPorts = SZ_2K;
+
+        status = pcmcia_register_socket(&cf->socket);
+        if (status < 0)
+                goto fail2;
+
+        return 0;
+
+fail2:
+        iounmap((void __iomem *) cf->socket.io_offset);
+        release_mem_region(AT91_CF_BASE, CF_SIZE);
+fail1:
+        if (board->irq_pin)
+                free_irq(board->irq_pin, cf);
+fail0a:
+        free_irq(board->det_pin, cf);
+fail0:
+        at91_sys_write(AT91_EBI_CSA, csa);
+        kfree(cf);
+        return status;
+}
+
+static int __exit at91_cf_remove(struct device *dev)
+{
+        struct at91_cf_socket *cf = dev_get_drvdata(dev);
+        unsigned int csa;
+
+        pcmcia_unregister_socket(&cf->socket);
+        free_irq(cf->board->irq_pin, cf);
+        free_irq(cf->board->det_pin, cf);
+        iounmap((void __iomem *) cf->socket.io_offset);
+        release_mem_region(AT91_CF_BASE, CF_SIZE);
+
+        csa = at91_sys_read(AT91_EBI_CSA);
+        at91_sys_write(AT91_EBI_CSA, csa & ~AT91_EBI_CS4A);
+
+        kfree(cf);
+        return 0;
+}
+
+static struct device_driver at91_cf_driver = {
+        .name           = (char *) driver_name,
+        .bus            = &platform_bus_type,
+        .probe          = at91_cf_probe,
+        .remove         = __exit_p(at91_cf_remove),
+        .suspend        = pcmcia_socket_dev_suspend,
+        .resume         = pcmcia_socket_dev_resume,
+};
+
+/*--------------------------------------------------------------------------*/
+
+static int __init at91_cf_init(void)
+{
+        return driver_register(&at91_cf_driver);
+}
+module_init(at91_cf_init);
+
+static void __exit at91_cf_exit(void)
+{
+        driver_unregister(&at91_cf_driver);
+}
+module_exit(at91_cf_exit);
+
+MODULE_DESCRIPTION("AT91 Compact Flash Driver");
+MODULE_AUTHOR("David Brownell");
+MODULE_LICENSE("GPL");