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)                                          \
  30 void 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 }                                                                         \
  36 EXPORT_SYMBOL_GPL(mpc8xxx_spi_rx_buf_##type);
  37
  38 #define MPC8XXX_SPI_TX_BUF(type)                                \
  39 u32 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 EXPORT_SYMBOL_GPL(mpc8xxx_spi_tx_buf_##type);
  50
  51 MPC8XXX_SPI_RX_BUF(u8)
  52 MPC8XXX_SPI_RX_BUF(u16)
  53 MPC8XXX_SPI_RX_BUF(u32)
  54 MPC8XXX_SPI_TX_BUF(u8)
  55 MPC8XXX_SPI_TX_BUF(u16)
  56 MPC8XXX_SPI_TX_BUF(u32)
  57
  58 struct 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 }
  62 EXPORT_SYMBOL_GPL(to_of_pinfo);
  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 EXPORT_SYMBOL_GPL(mpc8xxx_spi_strmode);
  79
  80 void 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 }
 111 EXPORT_SYMBOL_GPL(mpc8xxx_spi_probe);
 112
 113 int 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 }
 158 EXPORT_SYMBOL_GPL(of_mpc8xxx_spi_probe);
 159
 160 MODULE_LICENSE("GPL");