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/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)                                          \
  33 void 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)                                \
  41 u32 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
  52 MPC8XXX_SPI_RX_BUF(u8)
  53 MPC8XXX_SPI_RX_BUF(u16)
  54 MPC8XXX_SPI_RX_BUF(u32)
  55 MPC8XXX_SPI_TX_BUF(u8)
  56 MPC8XXX_SPI_TX_BUF(u16)
  57 MPC8XXX_SPI_TX_BUF(u32)
  58
  59 struct 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
  64 const 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 }
  78
  79 void mpc8xxx_spi_probe(struct device *dev, struct resource *mem,
  80                         unsigned int irq)
  81 {
  82         struct fsl_spi_platform_data *pdata = dev_get_platdata(dev);
  83         struct spi_master *master;
  84         struct mpc8xxx_spi *mpc8xxx_spi;
  85
  86         master = dev_get_drvdata(dev);
  87
  88         /* the spi->mode bits understood by this driver: */
  89         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH
  90                         | SPI_LSB_FIRST | SPI_LOOP;
  91
  92         master->dev.of_node = dev->of_node;
  93
  94         mpc8xxx_spi = spi_master_get_devdata(master);
  95         mpc8xxx_spi->dev = dev;
  96         mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8;
  97         mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8;
  98         mpc8xxx_spi->flags = pdata->flags;
  99         mpc8xxx_spi->spibrg = pdata->sysclk;
 100         mpc8xxx_spi->irq = irq;
 101
 102         mpc8xxx_spi->rx_shift = 0;
 103         mpc8xxx_spi->tx_shift = 0;
 104
 105         init_completion(&mpc8xxx_spi->done);
 106
 107         master->bus_num = pdata->bus_num;
 108         master->num_chipselect = pdata->max_chipselect;
 109
 110         init_completion(&mpc8xxx_spi->done);
 111 }
 112
 113 int mpc8xxx_spi_remove(struct device *dev)
 114 {
 115         struct mpc8xxx_spi *mpc8xxx_spi;
 116         struct spi_master *master;
 117
 118         master = dev_get_drvdata(dev);
 119         mpc8xxx_spi = spi_master_get_devdata(master);
 120
 121         spi_unregister_master(master);
 122
 123         free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
 124
 125         if (mpc8xxx_spi->spi_remove)
 126                 mpc8xxx_spi->spi_remove(mpc8xxx_spi);
 127
 128         return 0;
 129 }
 130
 131 int of_mpc8xxx_spi_probe(struct platform_device *ofdev)
 132 {
 133         struct device *dev = &ofdev->dev;
 134         struct device_node *np = ofdev->dev.of_node;
 135         struct mpc8xxx_spi_probe_info *pinfo;
 136         struct fsl_spi_platform_data *pdata;
 137         const void *prop;
 138         int ret = -ENOMEM;
 139
 140         pinfo = devm_kzalloc(&ofdev->dev, sizeof(*pinfo), GFP_KERNEL);
 141         if (!pinfo)
 142                 return ret;
 143
 144         pdata = &pinfo->pdata;
 145         dev->platform_data = pdata;
 146
 147         /* Allocate bus num dynamically. */
 148         pdata->bus_num = -1;
 149
 150 #ifdef CONFIG_FSL_SOC
 151         /* SPI controller is either clocked from QE or SoC clock. */
 152         pdata->sysclk = get_brgfreq();
 153         if (pdata->sysclk == -1) {
 154                 pdata->sysclk = fsl_get_sys_freq();
 155                 if (pdata->sysclk == -1)
 156                         return -ENODEV;
 157         }
 158 #else
 159         ret = of_property_read_u32(np, "clock-frequency", &pdata->sysclk);
 160         if (ret)
 161                 return ret;
 162 #endif
 163
 164         prop = of_get_property(np, "mode", NULL);
 165         if (prop && !strcmp(prop, "cpu-qe"))
 166                 pdata->flags = SPI_QE_CPU_MODE;
 167         else if (prop && !strcmp(prop, "qe"))
 168                 pdata->flags = SPI_CPM_MODE | SPI_QE;
 169         else if (of_device_is_compatible(np, "fsl,cpm2-spi"))
 170                 pdata->flags = SPI_CPM_MODE | SPI_CPM2;
 171         else if (of_device_is_compatible(np, "fsl,cpm1-spi"))
 172                 pdata->flags = SPI_CPM_MODE | SPI_CPM1;
 173
 174         return 0;
 175 }