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#ifdef CONFIG_FSL_SOC
  27#include <sysdev/fsl_soc.h>
  28#endif
  29
  30#include "spi-fsl-lib.h"
  31
  32#define MPC8XXX_SPI_RX_BUF(type)                                          \
  33void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \
  34{                                                                         \
  35        type *rx = mpc8xxx_spi->rx;                                       \
  36        *rx++ = (type)(data >> mpc8xxx_spi->rx_shift);                    \
  37        mpc8xxx_spi->rx = rx;                                             \
  38}
  39
  40#define MPC8XXX_SPI_TX_BUF(type)                                \
  41u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi)  \
  42{                                                               \
  43        u32 data;                                               \
  44        const type *tx = mpc8xxx_spi->tx;                       \
  45        if (!tx)                                                \
  46                return 0;                                       \
  47        data = *tx++ << mpc8xxx_spi->tx_shift;                  \
  48        mpc8xxx_spi->tx = tx;                                   \
  49        return data;                                            \
  50}
  51
  52MPC8XXX_SPI_RX_BUF(u8)
  53MPC8XXX_SPI_RX_BUF(u16)
  54MPC8XXX_SPI_RX_BUF(u32)
  55MPC8XXX_SPI_TX_BUF(u8)
  56MPC8XXX_SPI_TX_BUF(u16)
  57MPC8XXX_SPI_TX_BUF(u32)
  58
  59struct mpc8xxx_spi_probe_info *to_of_pinfo(struct fsl_spi_platform_data *pdata)
  60{
  61        return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
  62}
  63
  64static void mpc8xxx_spi_work(struct work_struct *work)
  65{
  66        struct mpc8xxx_spi *mpc8xxx_spi = container_of(work, struct mpc8xxx_spi,
  67                                                       work);
  68
  69        spin_lock_irq(&mpc8xxx_spi->lock);
  70        while (!list_empty(&mpc8xxx_spi->queue)) {
  71                struct spi_message *m = container_of(mpc8xxx_spi->queue.next,
  72                                                   struct spi_message, queue);
  73
  74                list_del_init(&m->queue);
  75                spin_unlock_irq(&mpc8xxx_spi->lock);
  76
  77                if (mpc8xxx_spi->spi_do_one_msg)
  78                        mpc8xxx_spi->spi_do_one_msg(m);
  79
  80                spin_lock_irq(&mpc8xxx_spi->lock);
  81        }
  82        spin_unlock_irq(&mpc8xxx_spi->lock);
  83}
  84
  85int mpc8xxx_spi_transfer(struct spi_device *spi,
  86                                struct spi_message *m)
  87{
  88        struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
  89        unsigned long flags;
  90
  91        m->actual_length = 0;
  92        m->status = -EINPROGRESS;
  93
  94        spin_lock_irqsave(&mpc8xxx_spi->lock, flags);
  95        list_add_tail(&m->queue, &mpc8xxx_spi->queue);
  96        queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work);
  97        spin_unlock_irqrestore(&mpc8xxx_spi->lock, flags);
  98
  99        return 0;
 100}
 101
 102void mpc8xxx_spi_cleanup(struct spi_device *spi)
 103{
 104        kfree(spi->controller_state);
 105}
 106
 107const char *mpc8xxx_spi_strmode(unsigned int flags)
 108{
 109        if (flags & SPI_QE_CPU_MODE) {
 110                return "QE CPU";
 111        } else if (flags & SPI_CPM_MODE) {
 112                if (flags & SPI_QE)
 113                        return "QE";
 114                else if (flags & SPI_CPM2)
 115                        return "CPM2";
 116                else
 117                        return "CPM1";
 118        }
 119        return "CPU";
 120}
 121
 122int mpc8xxx_spi_probe(struct device *dev, struct resource *mem,
 123                        unsigned int irq)
 124{
 125        struct fsl_spi_platform_data *pdata = dev->platform_data;
 126        struct spi_master *master;
 127        struct mpc8xxx_spi *mpc8xxx_spi;
 128        int ret = 0;
 129
 130        master = dev_get_drvdata(dev);
 131
 132        /* the spi->mode bits understood by this driver: */
 133        master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH
 134                        | SPI_LSB_FIRST | SPI_LOOP;
 135
 136        master->transfer = mpc8xxx_spi_transfer;
 137        master->cleanup = mpc8xxx_spi_cleanup;
 138        master->dev.of_node = dev->of_node;
 139
 140        mpc8xxx_spi = spi_master_get_devdata(master);
 141        mpc8xxx_spi->dev = dev;
 142        mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8;
 143        mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8;
 144        mpc8xxx_spi->flags = pdata->flags;
 145        mpc8xxx_spi->spibrg = pdata->sysclk;
 146        mpc8xxx_spi->irq = irq;
 147
 148        mpc8xxx_spi->rx_shift = 0;
 149        mpc8xxx_spi->tx_shift = 0;
 150
 151        init_completion(&mpc8xxx_spi->done);
 152
 153        master->bus_num = pdata->bus_num;
 154        master->num_chipselect = pdata->max_chipselect;
 155
 156        spin_lock_init(&mpc8xxx_spi->lock);
 157        init_completion(&mpc8xxx_spi->done);
 158        INIT_WORK(&mpc8xxx_spi->work, mpc8xxx_spi_work);
 159        INIT_LIST_HEAD(&mpc8xxx_spi->queue);
 160
 161        mpc8xxx_spi->workqueue = create_singlethread_workqueue(
 162                dev_name(master->dev.parent));
 163        if (mpc8xxx_spi->workqueue == NULL) {
 164                ret = -EBUSY;
 165                goto err;
 166        }
 167
 168        return 0;
 169
 170err:
 171        return ret;
 172}
 173
 174int mpc8xxx_spi_remove(struct device *dev)
 175{
 176        struct mpc8xxx_spi *mpc8xxx_spi;
 177        struct spi_master *master;
 178
 179        master = dev_get_drvdata(dev);
 180        mpc8xxx_spi = spi_master_get_devdata(master);
 181
 182        flush_workqueue(mpc8xxx_spi->workqueue);
 183        destroy_workqueue(mpc8xxx_spi->workqueue);
 184        spi_unregister_master(master);
 185
 186        free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
 187
 188        if (mpc8xxx_spi->spi_remove)
 189                mpc8xxx_spi->spi_remove(mpc8xxx_spi);
 190
 191        return 0;
 192}
 193
 194int of_mpc8xxx_spi_probe(struct platform_device *ofdev)
 195{
 196        struct device *dev = &ofdev->dev;
 197        struct device_node *np = ofdev->dev.of_node;
 198        struct mpc8xxx_spi_probe_info *pinfo;
 199        struct fsl_spi_platform_data *pdata;
 200        const void *prop;
 201        int ret = -ENOMEM;
 202
 203        pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
 204        if (!pinfo)
 205                return -ENOMEM;
 206
 207        pdata = &pinfo->pdata;
 208        dev->platform_data = pdata;
 209
 210        /* Allocate bus num dynamically. */
 211        pdata->bus_num = -1;
 212
 213#ifdef CONFIG_FSL_SOC
 214        /* SPI controller is either clocked from QE or SoC clock. */
 215        pdata->sysclk = get_brgfreq();
 216        if (pdata->sysclk == -1) {
 217                pdata->sysclk = fsl_get_sys_freq();
 218                if (pdata->sysclk == -1) {
 219                        ret = -ENODEV;
 220                        goto err;
 221                }
 222        }
 223#else
 224        ret = of_property_read_u32(np, "clock-frequency", &pdata->sysclk);
 225        if (ret)
 226                goto err;
 227#endif
 228
 229        prop = of_get_property(np, "mode", NULL);
 230        if (prop && !strcmp(prop, "cpu-qe"))
 231                pdata->flags = SPI_QE_CPU_MODE;
 232        else if (prop && !strcmp(prop, "qe"))
 233                pdata->flags = SPI_CPM_MODE | SPI_QE;
 234        else if (of_device_is_compatible(np, "fsl,cpm2-spi"))
 235                pdata->flags = SPI_CPM_MODE | SPI_CPM2;
 236        else if (of_device_is_compatible(np, "fsl,cpm1-spi"))
 237                pdata->flags = SPI_CPM_MODE | SPI_CPM1;
 238
 239        return 0;
 240
 241err:
 242        kfree(pinfo);
 243        return ret;
 244}
 245
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