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