| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Lars-Peter Clausen | 2638 | 94.52% | 1 | 14.29% |
| Rafał Hibner | 86 | 3.08% | 1 | 14.29% |
| Alexandru Ardelean | 47 | 1.68% | 1 | 14.29% |
| Johan Hovold | 8 | 0.29% | 1 | 14.29% |
| Javier Martinez Canillas | 7 | 0.25% | 1 | 14.29% |
| Christophe Jaillet | 3 | 0.11% | 1 | 14.29% |
| Thomas Gleixner | 2 | 0.07% | 1 | 14.29% |
| Total | 2791 | 7 |
// SPDX-License-Identifier: GPL-2.0-only /* * SPI-Engine SPI controller driver * Copyright 2015 Analog Devices Inc. * Author: Lars-Peter Clausen <lars@metafoo.de> */ #include <linux/clk.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/of.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/spi/spi.h> #define SPI_ENGINE_VERSION_MAJOR(x) ((x >> 16) & 0xff) #define SPI_ENGINE_VERSION_MINOR(x) ((x >> 8) & 0xff) #define SPI_ENGINE_VERSION_PATCH(x) (x & 0xff) #define SPI_ENGINE_REG_VERSION 0x00 #define SPI_ENGINE_REG_RESET 0x40 #define SPI_ENGINE_REG_INT_ENABLE 0x80 #define SPI_ENGINE_REG_INT_PENDING 0x84 #define SPI_ENGINE_REG_INT_SOURCE 0x88 #define SPI_ENGINE_REG_SYNC_ID 0xc0 #define SPI_ENGINE_REG_CMD_FIFO_ROOM 0xd0 #define SPI_ENGINE_REG_SDO_FIFO_ROOM 0xd4 #define SPI_ENGINE_REG_SDI_FIFO_LEVEL 0xd8 #define SPI_ENGINE_REG_CMD_FIFO 0xe0 #define SPI_ENGINE_REG_SDO_DATA_FIFO 0xe4 #define SPI_ENGINE_REG_SDI_DATA_FIFO 0xe8 #define SPI_ENGINE_REG_SDI_DATA_FIFO_PEEK 0xec #define SPI_ENGINE_INT_CMD_ALMOST_EMPTY BIT(0) #define SPI_ENGINE_INT_SDO_ALMOST_EMPTY BIT(1) #define SPI_ENGINE_INT_SDI_ALMOST_FULL BIT(2) #define SPI_ENGINE_INT_SYNC BIT(3) #define SPI_ENGINE_CONFIG_CPHA BIT(0) #define SPI_ENGINE_CONFIG_CPOL BIT(1) #define SPI_ENGINE_CONFIG_3WIRE BIT(2) #define SPI_ENGINE_INST_TRANSFER 0x0 #define SPI_ENGINE_INST_ASSERT 0x1 #define SPI_ENGINE_INST_WRITE 0x2 #define SPI_ENGINE_INST_MISC 0x3 #define SPI_ENGINE_CMD_REG_CLK_DIV 0x0 #define SPI_ENGINE_CMD_REG_CONFIG 0x1 #define SPI_ENGINE_MISC_SYNC 0x0 #define SPI_ENGINE_MISC_SLEEP 0x1 #define SPI_ENGINE_TRANSFER_WRITE 0x1 #define SPI_ENGINE_TRANSFER_READ 0x2 #define SPI_ENGINE_CMD(inst, arg1, arg2) \ (((inst) << 12) | ((arg1) << 8) | (arg2)) #define SPI_ENGINE_CMD_TRANSFER(flags, n) \ SPI_ENGINE_CMD(SPI_ENGINE_INST_TRANSFER, (flags), (n)) #define SPI_ENGINE_CMD_ASSERT(delay, cs) \ SPI_ENGINE_CMD(SPI_ENGINE_INST_ASSERT, (delay), (cs)) #define SPI_ENGINE_CMD_WRITE(reg, val) \ SPI_ENGINE_CMD(SPI_ENGINE_INST_WRITE, (reg), (val)) #define SPI_ENGINE_CMD_SLEEP(delay) \ SPI_ENGINE_CMD(SPI_ENGINE_INST_MISC, SPI_ENGINE_MISC_SLEEP, (delay)) #define SPI_ENGINE_CMD_SYNC(id) \ SPI_ENGINE_CMD(SPI_ENGINE_INST_MISC, SPI_ENGINE_MISC_SYNC, (id)) struct spi_engine_program { unsigned int length; uint16_t instructions[]; }; struct spi_engine { struct clk *clk; struct clk *ref_clk; spinlock_t lock; void __iomem *base; struct spi_message *msg; struct spi_engine_program *p; unsigned cmd_length; const uint16_t *cmd_buf; struct spi_transfer *tx_xfer; unsigned int tx_length; const uint8_t *tx_buf; struct spi_transfer *rx_xfer; unsigned int rx_length; uint8_t *rx_buf; unsigned int sync_id; unsigned int completed_id; unsigned int int_enable; }; static void spi_engine_program_add_cmd(struct spi_engine_program *p, bool dry, uint16_t cmd) { if (!dry) p->instructions[p->length] = cmd; p->length++; } static unsigned int spi_engine_get_config(struct spi_device *spi) { unsigned int config = 0; if (spi->mode & SPI_CPOL) config |= SPI_ENGINE_CONFIG_CPOL; if (spi->mode & SPI_CPHA) config |= SPI_ENGINE_CONFIG_CPHA; if (spi->mode & SPI_3WIRE) config |= SPI_ENGINE_CONFIG_3WIRE; return config; } static unsigned int spi_engine_get_clk_div(struct spi_engine *spi_engine, struct spi_device *spi, struct spi_transfer *xfer) { unsigned int clk_div; clk_div = DIV_ROUND_UP(clk_get_rate(spi_engine->ref_clk), xfer->speed_hz * 2); if (clk_div > 255) clk_div = 255; else if (clk_div > 0) clk_div -= 1; return clk_div; } static void spi_engine_gen_xfer(struct spi_engine_program *p, bool dry, struct spi_transfer *xfer) { unsigned int len = xfer->len; while (len) { unsigned int n = min(len, 256U); unsigned int flags = 0; if (xfer->tx_buf) flags |= SPI_ENGINE_TRANSFER_WRITE; if (xfer->rx_buf) flags |= SPI_ENGINE_TRANSFER_READ; spi_engine_program_add_cmd(p, dry, SPI_ENGINE_CMD_TRANSFER(flags, n - 1)); len -= n; } } static void spi_engine_gen_sleep(struct spi_engine_program *p, bool dry, struct spi_engine *spi_engine, unsigned int clk_div, struct spi_transfer *xfer) { unsigned int spi_clk = clk_get_rate(spi_engine->ref_clk); unsigned int t; int delay; if (xfer->delay_usecs) { delay = xfer->delay_usecs; } else { delay = spi_delay_to_ns(&xfer->delay, xfer); if (delay < 0) return; delay /= 1000; } if (delay == 0) return; t = DIV_ROUND_UP(delay * spi_clk, (clk_div + 1) * 2); while (t) { unsigned int n = min(t, 256U); spi_engine_program_add_cmd(p, dry, SPI_ENGINE_CMD_SLEEP(n - 1)); t -= n; } } static void spi_engine_gen_cs(struct spi_engine_program *p, bool dry, struct spi_device *spi, bool assert) { unsigned int mask = 0xff; if (assert) mask ^= BIT(spi->chip_select); spi_engine_program_add_cmd(p, dry, SPI_ENGINE_CMD_ASSERT(1, mask)); } static int spi_engine_compile_message(struct spi_engine *spi_engine, struct spi_message *msg, bool dry, struct spi_engine_program *p) { struct spi_device *spi = msg->spi; struct spi_transfer *xfer; int clk_div, new_clk_div; bool cs_change = true; clk_div = -1; spi_engine_program_add_cmd(p, dry, SPI_ENGINE_CMD_WRITE(SPI_ENGINE_CMD_REG_CONFIG, spi_engine_get_config(spi))); list_for_each_entry(xfer, &msg->transfers, transfer_list) { new_clk_div = spi_engine_get_clk_div(spi_engine, spi, xfer); if (new_clk_div != clk_div) { clk_div = new_clk_div; spi_engine_program_add_cmd(p, dry, SPI_ENGINE_CMD_WRITE(SPI_ENGINE_CMD_REG_CLK_DIV, clk_div)); } if (cs_change) spi_engine_gen_cs(p, dry, spi, true); spi_engine_gen_xfer(p, dry, xfer); spi_engine_gen_sleep(p, dry, spi_engine, clk_div, xfer); cs_change = xfer->cs_change; if (list_is_last(&xfer->transfer_list, &msg->transfers)) cs_change = !cs_change; if (cs_change) spi_engine_gen_cs(p, dry, spi, false); } return 0; } static void spi_engine_xfer_next(struct spi_engine *spi_engine, struct spi_transfer **_xfer) { struct spi_message *msg = spi_engine->msg; struct spi_transfer *xfer = *_xfer; if (!xfer) { xfer = list_first_entry(&msg->transfers, struct spi_transfer, transfer_list); } else if (list_is_last(&xfer->transfer_list, &msg->transfers)) { xfer = NULL; } else { xfer = list_next_entry(xfer, transfer_list); } *_xfer = xfer; } static void spi_engine_tx_next(struct spi_engine *spi_engine) { struct spi_transfer *xfer = spi_engine->tx_xfer; do { spi_engine_xfer_next(spi_engine, &xfer); } while (xfer && !xfer->tx_buf); spi_engine->tx_xfer = xfer; if (xfer) { spi_engine->tx_length = xfer->len; spi_engine->tx_buf = xfer->tx_buf; } else { spi_engine->tx_buf = NULL; } } static void spi_engine_rx_next(struct spi_engine *spi_engine) { struct spi_transfer *xfer = spi_engine->rx_xfer; do { spi_engine_xfer_next(spi_engine, &xfer); } while (xfer && !xfer->rx_buf); spi_engine->rx_xfer = xfer; if (xfer) { spi_engine->rx_length = xfer->len; spi_engine->rx_buf = xfer->rx_buf; } else { spi_engine->rx_buf = NULL; } } static bool spi_engine_write_cmd_fifo(struct spi_engine *spi_engine) { void __iomem *addr = spi_engine->base + SPI_ENGINE_REG_CMD_FIFO; unsigned int n, m, i; const uint16_t *buf; n = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_CMD_FIFO_ROOM); while (n && spi_engine->cmd_length) { m = min(n, spi_engine->cmd_length); buf = spi_engine->cmd_buf; for (i = 0; i < m; i++) writel_relaxed(buf[i], addr); spi_engine->cmd_buf += m; spi_engine->cmd_length -= m; n -= m; } return spi_engine->cmd_length != 0; } static bool spi_engine_write_tx_fifo(struct spi_engine *spi_engine) { void __iomem *addr = spi_engine->base + SPI_ENGINE_REG_SDO_DATA_FIFO; unsigned int n, m, i; const uint8_t *buf; n = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_SDO_FIFO_ROOM); while (n && spi_engine->tx_length) { m = min(n, spi_engine->tx_length); buf = spi_engine->tx_buf; for (i = 0; i < m; i++) writel_relaxed(buf[i], addr); spi_engine->tx_buf += m; spi_engine->tx_length -= m; n -= m; if (spi_engine->tx_length == 0) spi_engine_tx_next(spi_engine); } return spi_engine->tx_length != 0; } static bool spi_engine_read_rx_fifo(struct spi_engine *spi_engine) { void __iomem *addr = spi_engine->base + SPI_ENGINE_REG_SDI_DATA_FIFO; unsigned int n, m, i; uint8_t *buf; n = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_SDI_FIFO_LEVEL); while (n && spi_engine->rx_length) { m = min(n, spi_engine->rx_length); buf = spi_engine->rx_buf; for (i = 0; i < m; i++) buf[i] = readl_relaxed(addr); spi_engine->rx_buf += m; spi_engine->rx_length -= m; n -= m; if (spi_engine->rx_length == 0) spi_engine_rx_next(spi_engine); } return spi_engine->rx_length != 0; } static irqreturn_t spi_engine_irq(int irq, void *devid) { struct spi_master *master = devid; struct spi_engine *spi_engine = spi_master_get_devdata(master); unsigned int disable_int = 0; unsigned int pending; pending = readl_relaxed(spi_engine->base + SPI_ENGINE_REG_INT_PENDING); if (pending & SPI_ENGINE_INT_SYNC) { writel_relaxed(SPI_ENGINE_INT_SYNC, spi_engine->base + SPI_ENGINE_REG_INT_PENDING); spi_engine->completed_id = readl_relaxed( spi_engine->base + SPI_ENGINE_REG_SYNC_ID); } spin_lock(&spi_engine->lock); if (pending & SPI_ENGINE_INT_CMD_ALMOST_EMPTY) { if (!spi_engine_write_cmd_fifo(spi_engine)) disable_int |= SPI_ENGINE_INT_CMD_ALMOST_EMPTY; } if (pending & SPI_ENGINE_INT_SDO_ALMOST_EMPTY) { if (!spi_engine_write_tx_fifo(spi_engine)) disable_int |= SPI_ENGINE_INT_SDO_ALMOST_EMPTY; } if (pending & (SPI_ENGINE_INT_SDI_ALMOST_FULL | SPI_ENGINE_INT_SYNC)) { if (!spi_engine_read_rx_fifo(spi_engine)) disable_int |= SPI_ENGINE_INT_SDI_ALMOST_FULL; } if (pending & SPI_ENGINE_INT_SYNC) { if (spi_engine->msg && spi_engine->completed_id == spi_engine->sync_id) { struct spi_message *msg = spi_engine->msg; kfree(spi_engine->p); msg->status = 0; msg->actual_length = msg->frame_length; spi_engine->msg = NULL; spi_finalize_current_message(master); disable_int |= SPI_ENGINE_INT_SYNC; } } if (disable_int) { spi_engine->int_enable &= ~disable_int; writel_relaxed(spi_engine->int_enable, spi_engine->base + SPI_ENGINE_REG_INT_ENABLE); } spin_unlock(&spi_engine->lock); return IRQ_HANDLED; } static int spi_engine_transfer_one_message(struct spi_master *master, struct spi_message *msg) { struct spi_engine_program p_dry, *p; struct spi_engine *spi_engine = spi_master_get_devdata(master); unsigned int int_enable = 0; unsigned long flags; size_t size; p_dry.length = 0; spi_engine_compile_message(spi_engine, msg, true, &p_dry); size = sizeof(*p->instructions) * (p_dry.length + 1); p = kzalloc(sizeof(*p) + size, GFP_KERNEL); if (!p) return -ENOMEM; spi_engine_compile_message(spi_engine, msg, false, p); spin_lock_irqsave(&spi_engine->lock, flags); spi_engine->sync_id = (spi_engine->sync_id + 1) & 0xff; spi_engine_program_add_cmd(p, false, SPI_ENGINE_CMD_SYNC(spi_engine->sync_id)); spi_engine->msg = msg; spi_engine->p = p; spi_engine->cmd_buf = p->instructions; spi_engine->cmd_length = p->length; if (spi_engine_write_cmd_fifo(spi_engine)) int_enable |= SPI_ENGINE_INT_CMD_ALMOST_EMPTY; spi_engine_tx_next(spi_engine); if (spi_engine_write_tx_fifo(spi_engine)) int_enable |= SPI_ENGINE_INT_SDO_ALMOST_EMPTY; spi_engine_rx_next(spi_engine); if (spi_engine->rx_length != 0) int_enable |= SPI_ENGINE_INT_SDI_ALMOST_FULL; int_enable |= SPI_ENGINE_INT_SYNC; writel_relaxed(int_enable, spi_engine->base + SPI_ENGINE_REG_INT_ENABLE); spi_engine->int_enable = int_enable; spin_unlock_irqrestore(&spi_engine->lock, flags); return 0; } static int spi_engine_probe(struct platform_device *pdev) { struct spi_engine *spi_engine; struct spi_master *master; unsigned int version; int irq; int ret; irq = platform_get_irq(pdev, 0); if (irq <= 0) return -ENXIO; spi_engine = devm_kzalloc(&pdev->dev, sizeof(*spi_engine), GFP_KERNEL); if (!spi_engine) return -ENOMEM; master = spi_alloc_master(&pdev->dev, 0); if (!master) return -ENOMEM; spi_master_set_devdata(master, spi_engine); spin_lock_init(&spi_engine->lock); spi_engine->clk = devm_clk_get(&pdev->dev, "s_axi_aclk"); if (IS_ERR(spi_engine->clk)) { ret = PTR_ERR(spi_engine->clk); goto err_put_master; } spi_engine->ref_clk = devm_clk_get(&pdev->dev, "spi_clk"); if (IS_ERR(spi_engine->ref_clk)) { ret = PTR_ERR(spi_engine->ref_clk); goto err_put_master; } ret = clk_prepare_enable(spi_engine->clk); if (ret) goto err_put_master; ret = clk_prepare_enable(spi_engine->ref_clk); if (ret) goto err_clk_disable; spi_engine->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(spi_engine->base)) { ret = PTR_ERR(spi_engine->base); goto err_ref_clk_disable; } version = readl(spi_engine->base + SPI_ENGINE_REG_VERSION); if (SPI_ENGINE_VERSION_MAJOR(version) != 1) { dev_err(&pdev->dev, "Unsupported peripheral version %u.%u.%c\n", SPI_ENGINE_VERSION_MAJOR(version), SPI_ENGINE_VERSION_MINOR(version), SPI_ENGINE_VERSION_PATCH(version)); ret = -ENODEV; goto err_ref_clk_disable; } writel_relaxed(0x00, spi_engine->base + SPI_ENGINE_REG_RESET); writel_relaxed(0xff, spi_engine->base + SPI_ENGINE_REG_INT_PENDING); writel_relaxed(0x00, spi_engine->base + SPI_ENGINE_REG_INT_ENABLE); ret = request_irq(irq, spi_engine_irq, 0, pdev->name, master); if (ret) goto err_ref_clk_disable; master->dev.of_node = pdev->dev.of_node; master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_3WIRE; master->bits_per_word_mask = SPI_BPW_MASK(8); master->max_speed_hz = clk_get_rate(spi_engine->ref_clk) / 2; master->transfer_one_message = spi_engine_transfer_one_message; master->num_chipselect = 8; ret = spi_register_master(master); if (ret) goto err_free_irq; platform_set_drvdata(pdev, master); return 0; err_free_irq: free_irq(irq, master); err_ref_clk_disable: clk_disable_unprepare(spi_engine->ref_clk); err_clk_disable: clk_disable_unprepare(spi_engine->clk); err_put_master: spi_master_put(master); return ret; } static int spi_engine_remove(struct platform_device *pdev) { struct spi_master *master = spi_master_get(platform_get_drvdata(pdev)); struct spi_engine *spi_engine = spi_master_get_devdata(master); int irq = platform_get_irq(pdev, 0); spi_unregister_master(master); free_irq(irq, master); spi_master_put(master); writel_relaxed(0xff, spi_engine->base + SPI_ENGINE_REG_INT_PENDING); writel_relaxed(0x00, spi_engine->base + SPI_ENGINE_REG_INT_ENABLE); writel_relaxed(0x01, spi_engine->base + SPI_ENGINE_REG_RESET); clk_disable_unprepare(spi_engine->ref_clk); clk_disable_unprepare(spi_engine->clk); return 0; } static const struct of_device_id spi_engine_match_table[] = { { .compatible = "adi,axi-spi-engine-1.00.a" }, { }, }; MODULE_DEVICE_TABLE(of, spi_engine_match_table); static struct platform_driver spi_engine_driver = { .probe = spi_engine_probe, .remove = spi_engine_remove, .driver = { .name = "spi-engine", .of_match_table = spi_engine_match_table, }, }; module_platform_driver(spi_engine_driver); MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); MODULE_DESCRIPTION("Analog Devices SPI engine peripheral driver"); MODULE_LICENSE("GPL");
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