drivers/spi/spi-rpc-if.c

   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
  19 static 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
  64 static 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
  78 static 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
  92 static 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
 112 static 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
 123 static 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
 130 static 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
 168 static 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
 179 static 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
 186 static 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
 193 static SIMPLE_DEV_PM_OPS(rpcif_spi_pm_ops, rpcif_spi_suspend, rpcif_spi_resume);
 194
 195 static 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 };
 205 module_platform_driver(rpcif_spi_driver);
 206
 207 MODULE_DESCRIPTION("Renesas RPC-IF SPI driver");
 208 MODULE_LICENSE("GPL v2");