linux/drivers/spi/spi-rpc-if.c
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   1// SPDX-License-Identifier: GPL-2.0
   2//
   3// RPC-IF SPI/QSPI/Octa driver
   4//
   5// Copyright (C) 2018 ~ 2019 Renesas Solutions Corp.
   6// Copyright (C) 2019 Macronix International Co., Ltd.
   7// Copyright (C) 2019 - 2020 Cogent Embedded, Inc.
   8//
   9
  10#include <linux/module.h>
  11#include <linux/platform_device.h>
  12#include <linux/spi/spi.h>
  13#include <linux/spi/spi-mem.h>
  14
  15#include <memory/renesas-rpc-if.h>
  16
  17#include <asm/unaligned.h>
  18
  19static void rpcif_spi_mem_prepare(struct spi_device *spi_dev,
  20                                  const struct spi_mem_op *spi_op,
  21                                  u64 *offs, size_t *len)
  22{
  23        struct rpcif *rpc = spi_controller_get_devdata(spi_dev->controller);
  24        struct rpcif_op rpc_op = { };
  25
  26        rpc_op.cmd.opcode = spi_op->cmd.opcode;
  27        rpc_op.cmd.buswidth = spi_op->cmd.buswidth;
  28
  29        if (spi_op->addr.nbytes) {
  30                rpc_op.addr.buswidth = spi_op->addr.buswidth;
  31                rpc_op.addr.nbytes = spi_op->addr.nbytes;
  32                rpc_op.addr.val = spi_op->addr.val;
  33        }
  34
  35        if (spi_op->dummy.nbytes) {
  36                rpc_op.dummy.buswidth = spi_op->dummy.buswidth;
  37                rpc_op.dummy.ncycles  = spi_op->dummy.nbytes * 8 /
  38                                        spi_op->dummy.buswidth;
  39        }
  40
  41        if (spi_op->data.nbytes || (offs && len)) {
  42                rpc_op.data.buswidth = spi_op->data.buswidth;
  43                rpc_op.data.nbytes = spi_op->data.nbytes;
  44                switch (spi_op->data.dir) {
  45                case SPI_MEM_DATA_IN:
  46                        rpc_op.data.dir = RPCIF_DATA_IN;
  47                        rpc_op.data.buf.in = spi_op->data.buf.in;
  48                        break;
  49                case SPI_MEM_DATA_OUT:
  50                        rpc_op.data.dir = RPCIF_DATA_OUT;
  51                        rpc_op.data.buf.out = spi_op->data.buf.out;
  52                        break;
  53                case SPI_MEM_NO_DATA:
  54                        rpc_op.data.dir = RPCIF_NO_DATA;
  55                        break;
  56                }
  57        } else  {
  58                rpc_op.data.dir = RPCIF_NO_DATA;
  59        }
  60
  61        rpcif_prepare(rpc, &rpc_op, offs, len);
  62}
  63
  64static bool rpcif_spi_mem_supports_op(struct spi_mem *mem,
  65                                      const struct spi_mem_op *op)
  66{
  67        if (!spi_mem_default_supports_op(mem, op))
  68                return false;
  69
  70        if (op->data.buswidth > 4 || op->addr.buswidth > 4 ||
  71            op->dummy.buswidth > 4 || op->cmd.buswidth > 4 ||
  72            op->addr.nbytes > 4)
  73                return false;
  74
  75        return true;
  76}
  77
  78static ssize_t rpcif_spi_mem_dirmap_read(struct spi_mem_dirmap_desc *desc,
  79                                         u64 offs, size_t len, void *buf)
  80{
  81        struct rpcif *rpc =
  82                spi_controller_get_devdata(desc->mem->spi->controller);
  83
  84        if (offs + desc->info.offset + len > U32_MAX)
  85                return -EINVAL;
  86
  87        rpcif_spi_mem_prepare(desc->mem->spi, &desc->info.op_tmpl, &offs, &len);
  88
  89        return rpcif_dirmap_read(rpc, offs, len, buf);
  90}
  91
  92static int rpcif_spi_mem_dirmap_create(struct spi_mem_dirmap_desc *desc)
  93{
  94        struct rpcif *rpc =
  95                spi_controller_get_devdata(desc->mem->spi->controller);
  96
  97        if (desc->info.offset + desc->info.length > U32_MAX)
  98                return -ENOTSUPP;
  99
 100        if (!rpcif_spi_mem_supports_op(desc->mem, &desc->info.op_tmpl))
 101                return -ENOTSUPP;
 102
 103        if (!rpc->dirmap && desc->info.op_tmpl.data.dir == SPI_MEM_DATA_IN)
 104                return -ENOTSUPP;
 105
 106        if (desc->info.op_tmpl.data.dir == SPI_MEM_DATA_OUT)
 107                return -ENOTSUPP;
 108
 109        return 0;
 110}
 111
 112static int rpcif_spi_mem_exec_op(struct spi_mem *mem,
 113                                 const struct spi_mem_op *op)
 114{
 115        struct rpcif *rpc =
 116                spi_controller_get_devdata(mem->spi->controller);
 117
 118        rpcif_spi_mem_prepare(mem->spi, op, NULL, NULL);
 119
 120        return rpcif_manual_xfer(rpc);
 121}
 122
 123static const struct spi_controller_mem_ops rpcif_spi_mem_ops = {
 124        .supports_op    = rpcif_spi_mem_supports_op,
 125        .exec_op        = rpcif_spi_mem_exec_op,
 126        .dirmap_create  = rpcif_spi_mem_dirmap_create,
 127        .dirmap_read    = rpcif_spi_mem_dirmap_read,
 128};
 129
 130static int rpcif_spi_probe(struct platform_device *pdev)
 131{
 132        struct device *parent = pdev->dev.parent;
 133        struct spi_controller *ctlr;
 134        struct rpcif *rpc;
 135        int error;
 136
 137        ctlr = devm_spi_alloc_master(&pdev->dev, sizeof(*rpc));
 138        if (!ctlr)
 139                return -ENOMEM;
 140
 141        rpc = spi_controller_get_devdata(ctlr);
 142        rpcif_sw_init(rpc, parent);
 143
 144        platform_set_drvdata(pdev, ctlr);
 145
 146        ctlr->dev.of_node = parent->of_node;
 147
 148        rpcif_enable_rpm(rpc);
 149
 150        ctlr->num_chipselect = 1;
 151        ctlr->mem_ops = &rpcif_spi_mem_ops;
 152
 153        ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
 154        ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_TX_QUAD | SPI_RX_QUAD;
 155        ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX;
 156
 157        rpcif_hw_init(rpc, false);
 158
 159        error = spi_register_controller(ctlr);
 160        if (error) {
 161                dev_err(&pdev->dev, "spi_register_controller failed\n");
 162                rpcif_disable_rpm(rpc);
 163        }
 164
 165        return error;
 166}
 167
 168static int rpcif_spi_remove(struct platform_device *pdev)
 169{
 170        struct spi_controller *ctlr = platform_get_drvdata(pdev);
 171        struct rpcif *rpc = spi_controller_get_devdata(ctlr);
 172
 173        spi_unregister_controller(ctlr);
 174        rpcif_disable_rpm(rpc);
 175
 176        return 0;
 177}
 178
 179static int __maybe_unused rpcif_spi_suspend(struct device *dev)
 180{
 181        struct spi_controller *ctlr = dev_get_drvdata(dev);
 182
 183        return spi_controller_suspend(ctlr);
 184}
 185
 186static int __maybe_unused rpcif_spi_resume(struct device *dev)
 187{
 188        struct spi_controller *ctlr = dev_get_drvdata(dev);
 189
 190        return spi_controller_resume(ctlr);
 191}
 192
 193static SIMPLE_DEV_PM_OPS(rpcif_spi_pm_ops, rpcif_spi_suspend, rpcif_spi_resume);
 194
 195static struct platform_driver rpcif_spi_driver = {
 196        .probe  = rpcif_spi_probe,
 197        .remove = rpcif_spi_remove,
 198        .driver = {
 199                .name   = "rpc-if-spi",
 200#ifdef CONFIG_PM_SLEEP
 201                .pm     = &rpcif_spi_pm_ops,
 202#endif
 203        },
 204};
 205module_platform_driver(rpcif_spi_driver);
 206
 207MODULE_DESCRIPTION("Renesas RPC-IF SPI driver");
 208MODULE_LICENSE("GPL v2");
 209
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