drivers/spi/spi-fsl-lib.c

   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/dma-mapping.h>
  20 #include <linux/fsl_devices.h>
  21 #include <linux/interrupt.h>
  22 #include <linux/kernel.h>
  23 #include <linux/mm.h>
  24 #include <linux/module.h>
  25 #include <linux/of_platform.h>
  26 #include <linux/spi/spi.h>
  27 #ifdef CONFIG_FSL_SOC
  28 #include <sysdev/fsl_soc.h>
  29 #endif
  30
  31 #include "spi-fsl-lib.h"
  32
  33 #define MPC8XXX_SPI_RX_BUF(type)                                          \
  34 void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \
  35 {                                                                         \
  36         type *rx = mpc8xxx_spi->rx;                                       \
  37         *rx++ = (type)(data >> mpc8xxx_spi->rx_shift);                    \
  38         mpc8xxx_spi->rx = rx;                                             \
  39 }                                                                         \
  40 EXPORT_SYMBOL_GPL(mpc8xxx_spi_rx_buf_##type);
  41
  42 #define MPC8XXX_SPI_TX_BUF(type)                                \
  43 u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi)  \
  44 {                                                               \
  45         u32 data;                                               \
  46         const type *tx = mpc8xxx_spi->tx;                       \
  47         if (!tx)                                                \
  48                 return 0;                                       \
  49         data = *tx++ << mpc8xxx_spi->tx_shift;                  \
  50         mpc8xxx_spi->tx = tx;                                   \
  51         return data;                                            \
  52 }                                                               \
  53 EXPORT_SYMBOL_GPL(mpc8xxx_spi_tx_buf_##type);
  54
  55 MPC8XXX_SPI_RX_BUF(u8)
  56 MPC8XXX_SPI_RX_BUF(u16)
  57 MPC8XXX_SPI_RX_BUF(u32)
  58 MPC8XXX_SPI_TX_BUF(u8)
  59 MPC8XXX_SPI_TX_BUF(u16)
  60 MPC8XXX_SPI_TX_BUF(u32)
  61
  62 struct mpc8xxx_spi_probe_info *to_of_pinfo(struct fsl_spi_platform_data *pdata)
  63 {
  64         return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
  65 }
  66 EXPORT_SYMBOL_GPL(to_of_pinfo);
  67
  68 const char *mpc8xxx_spi_strmode(unsigned int flags)
  69 {
  70         if (flags & SPI_QE_CPU_MODE) {
  71                 return "QE CPU";
  72         } else if (flags & SPI_CPM_MODE) {
  73                 if (flags & SPI_QE)
  74                         return "QE";
  75                 else if (flags & SPI_CPM2)
  76                         return "CPM2";
  77                 else
  78                         return "CPM1";
  79         }
  80         return "CPU";
  81 }
  82 EXPORT_SYMBOL_GPL(mpc8xxx_spi_strmode);
  83
  84 void mpc8xxx_spi_probe(struct device *dev, struct resource *mem,
  85                         unsigned int irq)
  86 {
  87         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
  88         struct spi_master *master;
  89         struct mpc8xxx_spi *mpc8xxx_spi;
  90
  91         master = dev_get_drvdata(dev);
  92
  93         /* the spi->mode bits understood by this driver: */
  94         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH
  95                         | SPI_LSB_FIRST | SPI_LOOP;
  96
  97         master->dev.of_node = dev->of_node;
  98
  99         mpc8xxx_spi = spi_master_get_devdata(master);
 100         mpc8xxx_spi->dev = dev;
 101         mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8;
 102         mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8;
 103         mpc8xxx_spi->flags = pdata->flags;
 104         mpc8xxx_spi->spibrg = pdata->sysclk;
 105         mpc8xxx_spi->irq = irq;
 106
 107         mpc8xxx_spi->rx_shift = 0;
 108         mpc8xxx_spi->tx_shift = 0;
 109
 110         master->bus_num = pdata->bus_num;
 111         master->num_chipselect = pdata->max_chipselect;
 112
 113         init_completion(&mpc8xxx_spi->done);
 114 }
 115 EXPORT_SYMBOL_GPL(mpc8xxx_spi_probe);
 116
 117 int of_mpc8xxx_spi_probe(struct platform_device *ofdev)
 118 {
 119         struct device *dev = &ofdev->dev;
 120         struct device_node *np = ofdev->dev.of_node;
 121         struct mpc8xxx_spi_probe_info *pinfo;
 122         struct fsl_spi_platform_data *pdata;
 123         const void *prop;
 124         int ret = -ENOMEM;
 125
 126         pinfo = devm_kzalloc(&ofdev->dev, sizeof(*pinfo), GFP_KERNEL);
 127         if (!pinfo)
 128                 return ret;
 129
 130         pdata = &pinfo->pdata;
 131         dev->platform_data = pdata;
 132
 133         /* Allocate bus num dynamically. */
 134         pdata->bus_num = -1;
 135
 136 #ifdef CONFIG_FSL_SOC
 137         /* SPI controller is either clocked from QE or SoC clock. */
 138         pdata->sysclk = get_brgfreq();
 139         if (pdata->sysclk == -1) {
 140                 pdata->sysclk = fsl_get_sys_freq();
 141                 if (pdata->sysclk == -1)
 142                         return -ENODEV;
 143         }
 144 #else
 145         ret = of_property_read_u32(np, "clock-frequency", &pdata->sysclk);
 146         if (ret)
 147                 return ret;
 148 #endif
 149
 150         prop = of_get_property(np, "mode", NULL);
 151         if (prop && !strcmp(prop, "cpu-qe"))
 152                 pdata->flags = SPI_QE_CPU_MODE;
 153         else if (prop && !strcmp(prop, "qe"))
 154                 pdata->flags = SPI_CPM_MODE | SPI_QE;
 155         else if (of_device_is_compatible(np, "fsl,cpm2-spi"))
 156                 pdata->flags = SPI_CPM_MODE | SPI_CPM2;
 157         else if (of_device_is_compatible(np, "fsl,cpm1-spi"))
 158                 pdata->flags = SPI_CPM_MODE | SPI_CPM1;
 159
 160         return 0;
 161 }
 162 EXPORT_SYMBOL_GPL(of_mpc8xxx_spi_probe);
 163
 164 MODULE_LICENSE("GPL");