LXR linux/drivers/spi/spi-fsl-lib.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Freescale SPI/eSPI controller driver library.
   4 *
   5 * Maintainer: Kumar Gala
   6 *
   7 * Copyright (C) 2006 Polycom, Inc.
   8 *
   9 * CPM SPI and QE buffer descriptors mode support:
  10 * Copyright (c) 2009  MontaVista Software, Inc.
  11 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
  12 *
  13 * Copyright 2010 Freescale Semiconductor, Inc.
  14 */
  15#include <linux/dma-mapping.h>
  16#include <linux/fsl_devices.h>
  17#include <linux/interrupt.h>
  18#include <linux/kernel.h>
  19#include <linux/mm.h>
  20#include <linux/module.h>
  21#include <linux/of_platform.h>
  22#include <linux/spi/spi.h>
  23#ifdef CONFIG_FSL_SOC
  24#include <sysdev/fsl_soc.h>
  25#endif
  26
  27#include "spi-fsl-lib.h"
  28
  29#define MPC8XXX_SPI_RX_BUF(type)                                          \
  30void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \
  31{                                                                         \
  32        type *rx = mpc8xxx_spi->rx;                                       \
  33        *rx++ = (type)(data >> mpc8xxx_spi->rx_shift);                    \
  34        mpc8xxx_spi->rx = rx;                                             \
  35}                                                                         \
  36EXPORT_SYMBOL_GPL(mpc8xxx_spi_rx_buf_##type);
  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}                                                               \
  49EXPORT_SYMBOL_GPL(mpc8xxx_spi_tx_buf_##type);
  50
  51MPC8XXX_SPI_RX_BUF(u8)
  52MPC8XXX_SPI_RX_BUF(u16)
  53MPC8XXX_SPI_RX_BUF(u32)
  54MPC8XXX_SPI_TX_BUF(u8)
  55MPC8XXX_SPI_TX_BUF(u16)
  56MPC8XXX_SPI_TX_BUF(u32)
  57
  58struct mpc8xxx_spi_probe_info *to_of_pinfo(struct fsl_spi_platform_data *pdata)
  59{
  60        return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
  61}
  62EXPORT_SYMBOL_GPL(to_of_pinfo);
  63
  64const char *mpc8xxx_spi_strmode(unsigned int flags)
  65{
  66        if (flags & SPI_QE_CPU_MODE) {
  67                return "QE CPU";
  68        } else if (flags & SPI_CPM_MODE) {
  69                if (flags & SPI_QE)
  70                        return "QE";
  71                else if (flags & SPI_CPM2)
  72                        return "CPM2";
  73                else
  74                        return "CPM1";
  75        }
  76        return "CPU";
  77}
  78EXPORT_SYMBOL_GPL(mpc8xxx_spi_strmode);
  79
  80void mpc8xxx_spi_probe(struct device *dev, struct resource *mem,
  81                        unsigned int irq)
  82{
  83        struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
  84        struct spi_master *master;
  85        struct mpc8xxx_spi *mpc8xxx_spi;
  86
  87        master = dev_get_drvdata(dev);
  88
  89        /* the spi->mode bits understood by this driver: */
  90        master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH
  91                        | SPI_LSB_FIRST | SPI_LOOP;
  92
  93        master->dev.of_node = dev->of_node;
  94
  95        mpc8xxx_spi = spi_master_get_devdata(master);
  96        mpc8xxx_spi->dev = dev;
  97        mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8;
  98        mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8;
  99        mpc8xxx_spi->flags = pdata->flags;
 100        mpc8xxx_spi->spibrg = pdata->sysclk;
 101        mpc8xxx_spi->irq = irq;
 102
 103        mpc8xxx_spi->rx_shift = 0;
 104        mpc8xxx_spi->tx_shift = 0;
 105
 106        master->bus_num = pdata->bus_num;
 107        master->num_chipselect = pdata->max_chipselect;
 108
 109        init_completion(&mpc8xxx_spi->done);
 110}
 111EXPORT_SYMBOL_GPL(mpc8xxx_spi_probe);
 112
 113int of_mpc8xxx_spi_probe(struct platform_device *ofdev)
 114{
 115        struct device *dev = &ofdev->dev;
 116        struct device_node *np = ofdev->dev.of_node;
 117        struct mpc8xxx_spi_probe_info *pinfo;
 118        struct fsl_spi_platform_data *pdata;
 119        const void *prop;
 120        int ret = -ENOMEM;
 121
 122        pinfo = devm_kzalloc(&ofdev->dev, sizeof(*pinfo), GFP_KERNEL);
 123        if (!pinfo)
 124                return ret;
 125
 126        pdata = &pinfo->pdata;
 127        dev->platform_data = pdata;
 128
 129        /* Allocate bus num dynamically. */
 130        pdata->bus_num = -1;
 131
 132#ifdef CONFIG_FSL_SOC
 133        /* SPI controller is either clocked from QE or SoC clock. */
 134        pdata->sysclk = get_brgfreq();
 135        if (pdata->sysclk == -1) {
 136                pdata->sysclk = fsl_get_sys_freq();
 137                if (pdata->sysclk == -1)
 138                        return -ENODEV;
 139        }
 140#else
 141        ret = of_property_read_u32(np, "clock-frequency", &pdata->sysclk);
 142        if (ret)
 143                return ret;
 144#endif
 145
 146        prop = of_get_property(np, "mode", NULL);
 147        if (prop && !strcmp(prop, "cpu-qe"))
 148                pdata->flags = SPI_QE_CPU_MODE;
 149        else if (prop && !strcmp(prop, "qe"))
 150                pdata->flags = SPI_CPM_MODE | SPI_QE;
 151        else if (of_device_is_compatible(np, "fsl,cpm2-spi"))
 152                pdata->flags = SPI_CPM_MODE | SPI_CPM2;
 153        else if (of_device_is_compatible(np, "fsl,cpm1-spi"))
 154                pdata->flags = SPI_CPM_MODE | SPI_CPM1;
 155
 156        return 0;
 157}
 158EXPORT_SYMBOL_GPL(of_mpc8xxx_spi_probe);
 159
 160MODULE_LICENSE("GPL");
 161