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author | Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> | 2020-06-13 22:18:34 +0300 |
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committer | Mark Brown <broonie@kernel.org> | 2020-06-16 02:38:38 +0300 |
commit | eb8d6d464a27850498dced21a8450e85d4a02009 (patch) | |
tree | c99cd89a3a6f31863a2f194161575d4ea27fa2bf /drivers/spi/spi-rpc-if.c | |
parent | 064e8af7159539fc2310870841e7f215b4f633e9 (diff) | |
download | linux-eb8d6d464a27850498dced21a8450e85d4a02009.tar.xz |
spi: add Renesas RPC-IF driver
Add the SPI driver for the Renesas RPC-IF. It's the "front end" driver
using the "back end" APIs in the main driver to talk to the real hardware.
We only implement the 'spi-mem' interface -- there's no need to implement
the usual SPI driver methods...
Based on the original patch by Mason Yang <masonccyang@mxic.com.tw>.
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Link: https://lore.kernel.org/r/1ece0e6c-71af-f0f1-709e-571f4b0b4853@cogentembedded.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-rpc-if.c')
-rw-r--r-- | drivers/spi/spi-rpc-if.c | 216 |
1 files changed, 216 insertions, 0 deletions
diff --git a/drivers/spi/spi-rpc-if.c b/drivers/spi/spi-rpc-if.c new file mode 100644 index 000000000000..ed3e548227f4 --- /dev/null +++ b/drivers/spi/spi-rpc-if.c @@ -0,0 +1,216 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// RPC-IF SPI/QSPI/Octa driver +// +// Copyright (C) 2018 ~ 2019 Renesas Solutions Corp. +// Copyright (C) 2019 Macronix International Co., Ltd. +// Copyright (C) 2019 - 2020 Cogent Embedded, Inc. +// + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/spi/spi.h> +#include <linux/spi/spi-mem.h> + +#include <memory/renesas-rpc-if.h> + +#include <asm/unaligned.h> + +static void rpcif_spi_mem_prepare(struct spi_device *spi_dev, + const struct spi_mem_op *spi_op, + u64 *offs, size_t *len) +{ + struct rpcif *rpc = spi_controller_get_devdata(spi_dev->controller); + struct rpcif_op rpc_op = { }; + + rpc_op.cmd.opcode = spi_op->cmd.opcode; + rpc_op.cmd.buswidth = spi_op->cmd.buswidth; + + if (spi_op->addr.nbytes) { + rpc_op.addr.buswidth = spi_op->addr.buswidth; + rpc_op.addr.nbytes = spi_op->addr.nbytes; + rpc_op.addr.val = spi_op->addr.val; + } + + if (spi_op->dummy.nbytes) { + rpc_op.dummy.buswidth = spi_op->dummy.buswidth; + rpc_op.dummy.ncycles = spi_op->dummy.nbytes * 8 / + spi_op->dummy.buswidth; + } + + if (spi_op->data.nbytes || (offs && len)) { + rpc_op.data.buswidth = spi_op->data.buswidth; + rpc_op.data.nbytes = spi_op->data.nbytes; + switch (spi_op->data.dir) { + case SPI_MEM_DATA_IN: + rpc_op.data.dir = RPCIF_DATA_IN; + rpc_op.data.buf.in = spi_op->data.buf.in; + break; + case SPI_MEM_DATA_OUT: + rpc_op.data.dir = RPCIF_DATA_OUT; + rpc_op.data.buf.out = spi_op->data.buf.out; + break; + case SPI_MEM_NO_DATA: + rpc_op.data.dir = RPCIF_NO_DATA; + break; + } + } else { + rpc_op.data.dir = RPCIF_NO_DATA; + } + + rpcif_prepare(rpc, &rpc_op, offs, len); +} + +static bool rpcif_spi_mem_supports_op(struct spi_mem *mem, + const struct spi_mem_op *op) +{ + if (!spi_mem_default_supports_op(mem, op)) + return false; + + if (op->data.buswidth > 4 || op->addr.buswidth > 4 || + op->dummy.buswidth > 4 || op->cmd.buswidth > 4 || + op->addr.nbytes > 4) + return false; + + return true; +} + +static ssize_t rpcif_spi_mem_dirmap_read(struct spi_mem_dirmap_desc *desc, + u64 offs, size_t len, void *buf) +{ + struct rpcif *rpc = + spi_controller_get_devdata(desc->mem->spi->controller); + + if (offs + desc->info.offset + len > U32_MAX) + return -EINVAL; + + rpcif_spi_mem_prepare(desc->mem->spi, &desc->info.op_tmpl, &offs, &len); + + return rpcif_dirmap_read(rpc, offs, len, buf); +} + +static int rpcif_spi_mem_dirmap_create(struct spi_mem_dirmap_desc *desc) +{ + struct rpcif *rpc = + spi_controller_get_devdata(desc->mem->spi->controller); + + if (desc->info.offset + desc->info.length > U32_MAX) + return -ENOTSUPP; + + if (!rpcif_spi_mem_supports_op(desc->mem, &desc->info.op_tmpl)) + return -ENOTSUPP; + + if (!rpc->dirmap && desc->info.op_tmpl.data.dir == SPI_MEM_DATA_IN) + return -ENOTSUPP; + + if (desc->info.op_tmpl.data.dir == SPI_MEM_DATA_OUT) + return -ENOTSUPP; + + return 0; +} + +static int rpcif_spi_mem_exec_op(struct spi_mem *mem, + const struct spi_mem_op *op) +{ + struct rpcif *rpc = + spi_controller_get_devdata(mem->spi->controller); + + rpcif_spi_mem_prepare(mem->spi, op, NULL, NULL); + + return rpcif_manual_xfer(rpc); +} + +static const struct spi_controller_mem_ops rpcif_spi_mem_ops = { + .supports_op = rpcif_spi_mem_supports_op, + .exec_op = rpcif_spi_mem_exec_op, + .dirmap_create = rpcif_spi_mem_dirmap_create, + .dirmap_read = rpcif_spi_mem_dirmap_read, +}; + +static int rpcif_spi_probe(struct platform_device *pdev) +{ + struct device *parent = pdev->dev.parent; + struct spi_controller *ctlr; + struct rpcif *rpc; + int error; + + ctlr = spi_alloc_master(&pdev->dev, sizeof(*rpc)); + if (!ctlr) + return -ENOMEM; + + rpc = spi_controller_get_devdata(ctlr); + rpcif_sw_init(rpc, parent); + + platform_set_drvdata(pdev, ctlr); + + ctlr->dev.of_node = parent->of_node; + + rpcif_enable_rpm(rpc); + + ctlr->num_chipselect = 1; + ctlr->mem_ops = &rpcif_spi_mem_ops; + + ctlr->bits_per_word_mask = SPI_BPW_MASK(8); + ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_TX_QUAD | SPI_RX_QUAD; + ctlr->flags = SPI_CONTROLLER_HALF_DUPLEX; + + rpcif_hw_init(rpc, false); + + error = spi_register_controller(ctlr); + if (error) { + dev_err(&pdev->dev, "spi_register_controller failed\n"); + goto err_put_ctlr; + } + return 0; + +err_put_ctlr: + rpcif_disable_rpm(rpc); + spi_controller_put(ctlr); + + return error; +} + +static int rpcif_spi_remove(struct platform_device *pdev) +{ + struct spi_controller *ctlr = platform_get_drvdata(pdev); + struct rpcif *rpc = spi_controller_get_devdata(ctlr); + + spi_unregister_controller(ctlr); + rpcif_disable_rpm(rpc); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int rpcif_spi_suspend(struct device *dev) +{ + struct spi_controller *ctlr = dev_get_drvdata(dev); + + return spi_controller_suspend(ctlr); +} + +static int rpcif_spi_resume(struct device *dev) +{ + struct spi_controller *ctlr = dev_get_drvdata(dev); + + return spi_controller_resume(ctlr); +} + +static SIMPLE_DEV_PM_OPS(rpcif_spi_pm_ops, rpcif_spi_suspend, rpcif_spi_resume); +#define DEV_PM_OPS (&rpcif_spi_pm_ops) +#else +#define DEV_PM_OPS NULL +#endif + +static struct platform_driver rpcif_spi_driver = { + .probe = rpcif_spi_probe, + .remove = rpcif_spi_remove, + .driver = { + .name = "rpc-if-spi", + .pm = DEV_PM_OPS, + }, +}; +module_platform_driver(rpcif_spi_driver); + +MODULE_DESCRIPTION("Renesas RPC-IF SPI driver"); +MODULE_LICENSE("GPL v2"); |