linux/arch/arm/mach-omap2/gpmc-smc91x.c
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   1/*
   2 * linux/arch/arm/mach-omap2/gpmc-smc91x.c
   3 *
   4 * Copyright (C) 2009 Nokia Corporation
   5 * Contact:     Tony Lindgren
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 */
  11
  12#include <linux/kernel.h>
  13#include <linux/platform_device.h>
  14#include <linux/gpio.h>
  15#include <linux/delay.h>
  16#include <linux/interrupt.h>
  17#include <linux/io.h>
  18#include <linux/smc91x.h>
  19
  20#include <mach/board.h>
  21#include <mach/gpmc.h>
  22#include <mach/gpmc-smc91x.h>
  23
  24static struct omap_smc91x_platform_data *gpmc_cfg;
  25
  26static struct resource gpmc_smc91x_resources[] = {
  27        [0] = {
  28                .flags          = IORESOURCE_MEM,
  29        },
  30        [1] = {
  31                .flags          = IORESOURCE_IRQ,
  32        },
  33};
  34
  35static struct smc91x_platdata gpmc_smc91x_info = {
  36        .flags  = SMC91X_USE_16BIT | SMC91X_NOWAIT | SMC91X_IO_SHIFT_0,
  37};
  38
  39static struct platform_device gpmc_smc91x_device = {
  40        .name           = "smc91x",
  41        .id             = -1,
  42        .num_resources  = ARRAY_SIZE(gpmc_smc91x_resources),
  43        .resource       = gpmc_smc91x_resources,
  44        .dev            = {
  45                .platform_data = &gpmc_smc91x_info,
  46        },
  47};
  48
  49/*
  50 * Set the gpmc timings for smc91c96. The timings are taken
  51 * from the data sheet available at:
  52 * http://www.smsc.com/main/catalog/lan91c96.html
  53 * REVISIT: Level shifters can add at least to the access latency.
  54 */
  55static int smc91c96_gpmc_retime(void)
  56{
  57        struct gpmc_timings t;
  58        const int t3 = 10;      /* Figure 12.2 read and 12.4 write */
  59        const int t4_r = 20;    /* Figure 12.2 read */
  60        const int t4_w = 5;     /* Figure 12.4 write */
  61        const int t5 = 25;      /* Figure 12.2 read */
  62        const int t6 = 15;      /* Figure 12.2 read */
  63        const int t7 = 5;       /* Figure 12.4 write */
  64        const int t8 = 5;       /* Figure 12.4 write */
  65        const int t20 = 185;    /* Figure 12.2 read and 12.4 write */
  66        u32 l;
  67
  68        memset(&t, 0, sizeof(t));
  69
  70        /* Read timings */
  71        t.cs_on = 0;
  72        t.adv_on = t.cs_on;
  73        t.oe_on = t.adv_on + t3;
  74        t.access = t.oe_on + t5;
  75        t.oe_off = t.access;
  76        t.adv_rd_off = t.oe_off + max(t4_r, t6);
  77        t.cs_rd_off = t.oe_off;
  78        t.rd_cycle = t20 - t.oe_on;
  79
  80        /* Write timings */
  81        t.we_on = t.adv_on + t3;
  82
  83        if (cpu_is_omap34xx() && (gpmc_cfg->flags & GPMC_MUX_ADD_DATA)) {
  84                t.wr_data_mux_bus = t.we_on;
  85                t.we_off = t.wr_data_mux_bus + t7;
  86        } else
  87                t.we_off = t.we_on + t7;
  88        if (cpu_is_omap34xx())
  89                t.wr_access = t.we_off;
  90        t.adv_wr_off = t.we_off + max(t4_w, t8);
  91        t.cs_wr_off = t.we_off + t4_w;
  92        t.wr_cycle = t20 - t.we_on;
  93
  94        l = GPMC_CONFIG1_DEVICESIZE_16;
  95        if (gpmc_cfg->flags & GPMC_MUX_ADD_DATA)
  96                l |= GPMC_CONFIG1_MUXADDDATA;
  97        if (gpmc_cfg->flags & GPMC_READ_MON)
  98                l |= GPMC_CONFIG1_WAIT_READ_MON;
  99        if (gpmc_cfg->flags & GPMC_WRITE_MON)
 100                l |= GPMC_CONFIG1_WAIT_WRITE_MON;
 101        if (gpmc_cfg->wait_pin)
 102                l |= GPMC_CONFIG1_WAIT_PIN_SEL(gpmc_cfg->wait_pin);
 103        gpmc_cs_write_reg(gpmc_cfg->cs, GPMC_CS_CONFIG1, l);
 104
 105        /*
 106         * FIXME: Calculate the address and data bus muxed timings.
 107         * Note that at least adv_rd_off needs to be changed according
 108         * to omap3430 TRM Figure 11-11. Are the sdp boards using the
 109         * FPGA in between smc91x and omap as the timings are different
 110         * from above?
 111         */
 112        if (gpmc_cfg->flags & GPMC_MUX_ADD_DATA)
 113                return 0;
 114
 115        return gpmc_cs_set_timings(gpmc_cfg->cs, &t);
 116}
 117
 118/*
 119 * Initialize smc91x device connected to the GPMC. Note that we
 120 * assume that pin multiplexing is done in the board-*.c file,
 121 * or in the bootloader.
 122 */
 123void __init gpmc_smc91x_init(struct omap_smc91x_platform_data *board_data)
 124{
 125        unsigned long cs_mem_base;
 126        int ret;
 127
 128        gpmc_cfg = board_data;
 129
 130        if (gpmc_cfg->flags & GPMC_TIMINGS_SMC91C96)
 131                gpmc_cfg->retime = smc91c96_gpmc_retime;
 132
 133        if (gpmc_cs_request(gpmc_cfg->cs, SZ_16M, &cs_mem_base) < 0) {
 134                printk(KERN_ERR "Failed to request GPMC mem for smc91x\n");
 135                return;
 136        }
 137
 138        gpmc_smc91x_resources[0].start = cs_mem_base + 0x300;
 139        gpmc_smc91x_resources[0].end = cs_mem_base + 0x30f;
 140        gpmc_smc91x_resources[1].flags |= (gpmc_cfg->flags & IRQF_TRIGGER_MASK);
 141
 142        if (gpmc_cfg->retime) {
 143                ret = gpmc_cfg->retime();
 144                if (ret != 0)
 145                        goto free1;
 146        }
 147
 148        if (gpio_request(gpmc_cfg->gpio_irq, "SMC91X irq") < 0)
 149                goto free1;
 150
 151        gpio_direction_input(gpmc_cfg->gpio_irq);
 152        gpmc_smc91x_resources[1].start = gpio_to_irq(gpmc_cfg->gpio_irq);
 153
 154        if (gpmc_cfg->gpio_pwrdwn) {
 155                ret = gpio_request(gpmc_cfg->gpio_pwrdwn, "SMC91X powerdown");
 156                if (ret)
 157                        goto free2;
 158                gpio_direction_output(gpmc_cfg->gpio_pwrdwn, 0);
 159        }
 160
 161        if (gpmc_cfg->gpio_reset) {
 162                ret = gpio_request(gpmc_cfg->gpio_reset, "SMC91X reset");
 163                if (ret)
 164                        goto free3;
 165
 166                gpio_direction_output(gpmc_cfg->gpio_reset, 0);
 167                gpio_set_value(gpmc_cfg->gpio_reset, 1);
 168                msleep(100);
 169                gpio_set_value(gpmc_cfg->gpio_reset, 0);
 170        }
 171
 172        if (platform_device_register(&gpmc_smc91x_device) < 0) {
 173                printk(KERN_ERR "Unable to register smc91x device\n");
 174                gpio_free(gpmc_cfg->gpio_reset);
 175                goto free3;
 176        }
 177
 178        return;
 179
 180free3:
 181        if (gpmc_cfg->gpio_pwrdwn)
 182                gpio_free(gpmc_cfg->gpio_pwrdwn);
 183free2:
 184        gpio_free(gpmc_cfg->gpio_irq);
 185free1:
 186        gpmc_cs_free(gpmc_cfg->cs);
 187
 188        printk(KERN_ERR "Could not initialize smc91x\n");
 189}
 190