linux/drivers/spi/spi-fsl-lib.c
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   1/*
   2 * Freescale SPI/eSPI controller driver library.
   3 *
   4 * Maintainer: Kumar Gala
   5 *
   6 * Copyright (C) 2006 Polycom, Inc.
   7 *
   8 * CPM SPI and QE buffer descriptors mode support:
   9 * Copyright (c) 2009  MontaVista Software, Inc.
  10 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
  11 *
  12 * Copyright 2010 Freescale Semiconductor, Inc.
  13 *
  14 * This program is free software; you can redistribute  it and/or modify it
  15 * under  the terms of  the GNU General  Public License as published by the
  16 * Free Software Foundation;  either version 2 of the  License, or (at your
  17 * option) any later version.
  18 */
  19#include <linux/kernel.h>
  20#include <linux/interrupt.h>
  21#include <linux/fsl_devices.h>
  22#include <linux/dma-mapping.h>
  23#include <linux/mm.h>
  24#include <linux/of_platform.h>
  25#include <linux/spi/spi.h>
  26#include <sysdev/fsl_soc.h>
  27
  28#include "spi-fsl-lib.h"
  29
  30#define MPC8XXX_SPI_RX_BUF(type)                                          \
  31void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \
  32{                                                                         \
  33        type *rx = mpc8xxx_spi->rx;                                       \
  34        *rx++ = (type)(data >> mpc8xxx_spi->rx_shift);                    \
  35        mpc8xxx_spi->rx = rx;                                             \
  36}
  37
  38#define MPC8XXX_SPI_TX_BUF(type)                                \
  39u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi)  \
  40{                                                               \
  41        u32 data;                                               \
  42        const type *tx = mpc8xxx_spi->tx;                       \
  43        if (!tx)                                                \
  44                return 0;                                       \
  45        data = *tx++ << mpc8xxx_spi->tx_shift;                  \
  46        mpc8xxx_spi->tx = tx;                                   \
  47        return data;                                            \
  48}
  49
  50MPC8XXX_SPI_RX_BUF(u8)
  51MPC8XXX_SPI_RX_BUF(u16)
  52MPC8XXX_SPI_RX_BUF(u32)
  53MPC8XXX_SPI_TX_BUF(u8)
  54MPC8XXX_SPI_TX_BUF(u16)
  55MPC8XXX_SPI_TX_BUF(u32)
  56
  57struct mpc8xxx_spi_probe_info *to_of_pinfo(struct fsl_spi_platform_data *pdata)
  58{
  59        return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
  60}
  61
  62void mpc8xxx_spi_work(struct work_struct *work)
  63{
  64        struct mpc8xxx_spi *mpc8xxx_spi = container_of(work, struct mpc8xxx_spi,
  65                                                       work);
  66
  67        spin_lock_irq(&mpc8xxx_spi->lock);
  68        while (!list_empty(&mpc8xxx_spi->queue)) {
  69                struct spi_message *m = container_of(mpc8xxx_spi->queue.next,
  70                                                   struct spi_message, queue);
  71
  72                list_del_init(&m->queue);
  73                spin_unlock_irq(&mpc8xxx_spi->lock);
  74
  75                if (mpc8xxx_spi->spi_do_one_msg)
  76                        mpc8xxx_spi->spi_do_one_msg(m);
  77
  78                spin_lock_irq(&mpc8xxx_spi->lock);
  79        }
  80        spin_unlock_irq(&mpc8xxx_spi->lock);
  81}
  82
  83int mpc8xxx_spi_transfer(struct spi_device *spi,
  84                                struct spi_message *m)
  85{
  86        struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
  87        unsigned long flags;
  88
  89        m->actual_length = 0;
  90        m->status = -EINPROGRESS;
  91
  92        spin_lock_irqsave(&mpc8xxx_spi->lock, flags);
  93        list_add_tail(&m->queue, &mpc8xxx_spi->queue);
  94        queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work);
  95        spin_unlock_irqrestore(&mpc8xxx_spi->lock, flags);
  96
  97        return 0;
  98}
  99
 100void mpc8xxx_spi_cleanup(struct spi_device *spi)
 101{
 102        kfree(spi->controller_state);
 103}
 104
 105const char *mpc8xxx_spi_strmode(unsigned int flags)
 106{
 107        if (flags & SPI_QE_CPU_MODE) {
 108                return "QE CPU";
 109        } else if (flags & SPI_CPM_MODE) {
 110                if (flags & SPI_QE)
 111                        return "QE";
 112                else if (flags & SPI_CPM2)
 113                        return "CPM2";
 114                else
 115                        return "CPM1";
 116        }
 117        return "CPU";
 118}
 119
 120int mpc8xxx_spi_probe(struct device *dev, struct resource *mem,
 121                        unsigned int irq)
 122{
 123        struct fsl_spi_platform_data *pdata = dev->platform_data;
 124        struct spi_master *master;
 125        struct mpc8xxx_spi *mpc8xxx_spi;
 126        int ret = 0;
 127
 128        master = dev_get_drvdata(dev);
 129
 130        /* the spi->mode bits understood by this driver: */
 131        master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH
 132                        | SPI_LSB_FIRST | SPI_LOOP;
 133
 134        master->transfer = mpc8xxx_spi_transfer;
 135        master->cleanup = mpc8xxx_spi_cleanup;
 136        master->dev.of_node = dev->of_node;
 137
 138        mpc8xxx_spi = spi_master_get_devdata(master);
 139        mpc8xxx_spi->dev = dev;
 140        mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8;
 141        mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8;
 142        mpc8xxx_spi->flags = pdata->flags;
 143        mpc8xxx_spi->spibrg = pdata->sysclk;
 144        mpc8xxx_spi->irq = irq;
 145
 146        mpc8xxx_spi->rx_shift = 0;
 147        mpc8xxx_spi->tx_shift = 0;
 148
 149        init_completion(&mpc8xxx_spi->done);
 150
 151        master->bus_num = pdata->bus_num;
 152        master->num_chipselect = pdata->max_chipselect;
 153
 154        spin_lock_init(&mpc8xxx_spi->lock);
 155        init_completion(&mpc8xxx_spi->done);
 156        INIT_WORK(&mpc8xxx_spi->work, mpc8xxx_spi_work);
 157        INIT_LIST_HEAD(&mpc8xxx_spi->queue);
 158
 159        mpc8xxx_spi->workqueue = create_singlethread_workqueue(
 160                dev_name(master->dev.parent));
 161        if (mpc8xxx_spi->workqueue == NULL) {
 162                ret = -EBUSY;
 163                goto err;
 164        }
 165
 166        return 0;
 167
 168err:
 169        return ret;
 170}
 171
 172int __devexit mpc8xxx_spi_remove(struct device *dev)
 173{
 174        struct mpc8xxx_spi *mpc8xxx_spi;
 175        struct spi_master *master;
 176
 177        master = dev_get_drvdata(dev);
 178        mpc8xxx_spi = spi_master_get_devdata(master);
 179
 180        flush_workqueue(mpc8xxx_spi->workqueue);
 181        destroy_workqueue(mpc8xxx_spi->workqueue);
 182        spi_unregister_master(master);
 183
 184        free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
 185
 186        if (mpc8xxx_spi->spi_remove)
 187                mpc8xxx_spi->spi_remove(mpc8xxx_spi);
 188
 189        return 0;
 190}
 191
 192int __devinit of_mpc8xxx_spi_probe(struct platform_device *ofdev)
 193{
 194        struct device *dev = &ofdev->dev;
 195        struct device_node *np = ofdev->dev.of_node;
 196        struct mpc8xxx_spi_probe_info *pinfo;
 197        struct fsl_spi_platform_data *pdata;
 198        const void *prop;
 199        int ret = -ENOMEM;
 200
 201        pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
 202        if (!pinfo)
 203                return -ENOMEM;
 204
 205        pdata = &pinfo->pdata;
 206        dev->platform_data = pdata;
 207
 208        /* Allocate bus num dynamically. */
 209        pdata->bus_num = -1;
 210
 211        /* SPI controller is either clocked from QE or SoC clock. */
 212        pdata->sysclk = get_brgfreq();
 213        if (pdata->sysclk == -1) {
 214                pdata->sysclk = fsl_get_sys_freq();
 215                if (pdata->sysclk == -1) {
 216                        ret = -ENODEV;
 217                        goto err;
 218                }
 219        }
 220
 221        prop = of_get_property(np, "mode", NULL);
 222        if (prop && !strcmp(prop, "cpu-qe"))
 223                pdata->flags = SPI_QE_CPU_MODE;
 224        else if (prop && !strcmp(prop, "qe"))
 225                pdata->flags = SPI_CPM_MODE | SPI_QE;
 226        else if (of_device_is_compatible(np, "fsl,cpm2-spi"))
 227                pdata->flags = SPI_CPM_MODE | SPI_CPM2;
 228        else if (of_device_is_compatible(np, "fsl,cpm1-spi"))
 229                pdata->flags = SPI_CPM_MODE | SPI_CPM1;
 230
 231        return 0;
 232
 233err:
 234        kfree(pinfo);
 235        return ret;
 236}
 237
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