text: // SPDX-License-Identifier: GPL-2.0-only
  /*
   * This file is part of wl1271
   *
   * Copyright (C) 2008-2009 Nokia Corporation
   *
   * Contact: Luciano Coelho <luciano.coelho@nokia.com>
   */
  
  #include <linux/interrupt.h>
  #include <linux/irq.h>
  #include <linux/module.h>
  #include <linux/slab.h>
  #include <linux/swab.h>
  #include <linux/crc7.h>
  #include <linux/spi/spi.h>
  #include <linux/wl12xx.h>
  #include <linux/platform_device.h>
  #include <linux/of_irq.h>
  #include <linux/regulator/consumer.h>
  
  #include "wlcore.h"
  #include "wl12xx_80211.h"
  #include "io.h"
  
  #define WSPI_CMD_READ                 0x40000000
  #define WSPI_CMD_WRITE                0x00000000
  #define WSPI_CMD_FIXED                0x20000000
  #define WSPI_CMD_BYTE_LENGTH          0x1FFE0000
  #define WSPI_CMD_BYTE_LENGTH_OFFSET   17
  #define WSPI_CMD_BYTE_ADDR            0x0001FFFF
  
  #define WSPI_INIT_CMD_CRC_LEN       5
  
  #define WSPI_INIT_CMD_START         0x00
  #define WSPI_INIT_CMD_TX            0x40
  /* the extra bypass bit is sampled by the TNET as '1' */
  #define WSPI_INIT_CMD_BYPASS_BIT    0x80
  #define WSPI_INIT_CMD_FIXEDBUSY_LEN 0x07
  #define WSPI_INIT_CMD_EN_FIXEDBUSY  0x80
  #define WSPI_INIT_CMD_DIS_FIXEDBUSY 0x00
  #define WSPI_INIT_CMD_IOD           0x40
  #define WSPI_INIT_CMD_IP            0x20
  #define WSPI_INIT_CMD_CS            0x10
  #define WSPI_INIT_CMD_WS            0x08
  #define WSPI_INIT_CMD_WSPI          0x01
  #define WSPI_INIT_CMD_END           0x01
  
  #define WSPI_INIT_CMD_LEN           8
  
  #define HW_ACCESS_WSPI_FIXED_BUSY_LEN \
  		((WL1271_BUSY_WORD_LEN - 4) / sizeof(u32))
  #define HW_ACCESS_WSPI_INIT_CMD_MASK  0
  
  /* HW limitation: maximum possible chunk size is 4095 bytes */
  #define WSPI_MAX_CHUNK_SIZE    4092
  
  /*
   * wl18xx driver aggregation buffer size is (13 * 4K) compared to
   * (4 * 4K) for wl12xx, so use the larger buffer needed for wl18xx
   */
  #define SPI_AGGR_BUFFER_SIZE (13 * SZ_4K)
  
  /* Maximum number of SPI write chunks */
  #define WSPI_MAX_NUM_OF_CHUNKS \
  	((SPI_AGGR_BUFFER_SIZE / WSPI_MAX_CHUNK_SIZE) + 1)
  
  static const struct wilink_family_data wl127x_data = {
  	.name = "wl127x",
  	.nvs_name = "ti-connectivity/wl127x-nvs.bin",
  };
  
  static const struct wilink_family_data wl128x_data = {
  	.name = "wl128x",
  	.nvs_name = "ti-connectivity/wl128x-nvs.bin",
  };
  
  static const struct wilink_family_data wl18xx_data = {
  	.name = "wl18xx",
  	.cfg_name = "ti-connectivity/wl18xx-conf.bin",
  	.nvs_name = "ti-connectivity/wl1271-nvs.bin",
  };
  
  struct wl12xx_spi_glue {
  	struct device *dev;
  	struct platform_device *core;
  	struct regulator *reg; /* Power regulator */
  };
  
  static void wl12xx_spi_reset(struct device *child)
  {
  	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  	u8 *cmd;
  	struct spi_transfer t;
  	struct spi_message m;
  
  	cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  	if (!cmd) {
  		dev_err(child->parent,
  			"could not allocate cmd for spi reset\n");
  		return;
  	}
  
  	memset(&t, 0, sizeof(t));
  	spi_message_init(&m);
  
  	memset(cmd, 0xff, WSPI_INIT_CMD_LEN);
  
  	t.tx_buf = cmd;
  	t.len = WSPI_INIT_CMD_LEN;
  	spi_message_add_tail(&t, &m);
  
  	spi_sync(to_spi_device(glue->dev), &m);
  
  	kfree(cmd);
  }
  
  static void wl12xx_spi_init(struct device *child)
  {
  	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  	struct spi_transfer t;
  	struct spi_message m;
  	struct spi_device *spi = to_spi_device(glue->dev);
  	u8 *cmd = kzalloc(WSPI_INIT_CMD_LEN, GFP_KERNEL);
  
  	if (!cmd) {
  		dev_err(child->parent,
  			"could not allocate cmd for spi init\n");
  		return;
  	}
  
  	memset(&t, 0, sizeof(t));
  	spi_message_init(&m);
  
  	/*
  	 * Set WSPI_INIT_COMMAND
  	 * the data is being send from the MSB to LSB
  	 */
  	cmd[0] = 0xff;
  	cmd[1] = 0xff;
  	cmd[2] = WSPI_INIT_CMD_START | WSPI_INIT_CMD_TX;
  	cmd[3] = 0;
  	cmd[4] = 0;
  	cmd[5] = HW_ACCESS_WSPI_INIT_CMD_MASK << 3;
  	cmd[5] |= HW_ACCESS_WSPI_FIXED_BUSY_LEN & WSPI_INIT_CMD_FIXEDBUSY_LEN;
  
  	cmd[6] = WSPI_INIT_CMD_IOD | WSPI_INIT_CMD_IP | WSPI_INIT_CMD_CS
  		| WSPI_INIT_CMD_WSPI | WSPI_INIT_CMD_WS;
  
  	if (HW_ACCESS_WSPI_FIXED_BUSY_LEN == 0)
  		cmd[6] |= WSPI_INIT_CMD_DIS_FIXEDBUSY;
  	else
  		cmd[6] |= WSPI_INIT_CMD_EN_FIXEDBUSY;
  
  	cmd[7] = crc7_be(0, cmd+2, WSPI_INIT_CMD_CRC_LEN) | WSPI_INIT_CMD_END;
  
  	/*
  	 * The above is the logical order; it must actually be stored
  	 * in the buffer byte-swapped.
  	 */
  	__swab32s((u32 *)cmd);
  	__swab32s((u32 *)cmd+1);
  
  	t.tx_buf = cmd;
  	t.len = WSPI_INIT_CMD_LEN;
  	spi_message_add_tail(&t, &m);
  
  	spi_sync(to_spi_device(glue->dev), &m);
  
  	/* Send extra clocks with inverted CS (high). this is required
  	 * by the wilink family in order to successfully enter WSPI mode.
  	 */
  	spi->mode ^= SPI_CS_HIGH;
  	memset(&m, 0, sizeof(m));
  	spi_message_init(&m);
  
  	cmd[0] = 0xff;
  	cmd[1] = 0xff;
  	cmd[2] = 0xff;
  	cmd[3] = 0xff;
  	__swab32s((u32 *)cmd);
  
  	t.tx_buf = cmd;
  	t.len = 4;
  	spi_message_add_tail(&t, &m);
  
  	spi_sync(to_spi_device(glue->dev), &m);
  
  	/* Restore chip select configuration to normal */
  	spi->mode ^= SPI_CS_HIGH;
  	kfree(cmd);
  }
  
  #define WL1271_BUSY_WORD_TIMEOUT 1000
  
  static int wl12xx_spi_read_busy(struct device *child)
  {
  	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  	struct wl1271 *wl = dev_get_drvdata(child);
  	struct spi_transfer t[1];
  	struct spi_message m;
  	u32 *busy_buf;
  	int num_busy_bytes = 0;
  
  	/*
  	 * Read further busy words from SPI until a non-busy word is
  	 * encountered, then read the data itself into the buffer.
  	 */
  
  	num_busy_bytes = WL1271_BUSY_WORD_TIMEOUT;
  	busy_buf = wl->buffer_busyword;
  	while (num_busy_bytes) {
  		num_busy_bytes--;
  		spi_message_init(&m);
  		memset(t, 0, sizeof(t));
  		t[0].rx_buf = busy_buf;
  		t[0].len = sizeof(u32);
  		t[0].cs_change = true;
  		spi_message_add_tail(&t[0], &m);
  		spi_sync(to_spi_device(glue->dev), &m);
  
  		if (*busy_buf & 0x1)
  			return 0;
  	}
  
  	/* The SPI bus is unresponsive, the read failed. */
  	dev_err(child->parent, "SPI read busy-word timeout!\n");
  	return -ETIMEDOUT;
  }
  
  static int __must_check wl12xx_spi_raw_read(struct device *child, int addr,
  					    void *buf, size_t len, bool fixed)
  {
  	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  	struct wl1271 *wl = dev_get_drvdata(child);
  	struct spi_transfer t[2];
  	struct spi_message m;
  	u32 *busy_buf;
  	u32 *cmd;
  	u32 chunk_len;
  
  	while (len > 0) {
  		chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
  
  		cmd = &wl->buffer_cmd;
  		busy_buf = wl->buffer_busyword;
  
  		*cmd = 0;
  		*cmd |= WSPI_CMD_READ;
  		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
  			WSPI_CMD_BYTE_LENGTH;
  		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
  
  		if (fixed)
  			*cmd |= WSPI_CMD_FIXED;
  
  		spi_message_init(&m);
  		memset(t, 0, sizeof(t));
  
  		t[0].tx_buf = cmd;
  		t[0].len = 4;
  		t[0].cs_change = true;
  		spi_message_add_tail(&t[0], &m);
  
  		/* Busy and non busy words read */
  		t[1].rx_buf = busy_buf;
  		t[1].len = WL1271_BUSY_WORD_LEN;
  		t[1].cs_change = true;
  		spi_message_add_tail(&t[1], &m);
  
  		spi_sync(to_spi_device(glue->dev), &m);
  
  		if (!(busy_buf[WL1271_BUSY_WORD_CNT - 1] & 0x1) &&
  		    wl12xx_spi_read_busy(child)) {
  			memset(buf, 0, chunk_len);
  			return 0;
  		}
  
  		spi_message_init(&m);
  		memset(t, 0, sizeof(t));
  
  		t[0].rx_buf = buf;
  		t[0].len = chunk_len;
  		t[0].cs_change = true;
  		spi_message_add_tail(&t[0], &m);
  
  		spi_sync(to_spi_device(glue->dev), &m);
  
  		if (!fixed)
  			addr += chunk_len;
  		buf += chunk_len;
  		len -= chunk_len;
  	}
  
  	return 0;
  }
  
  static int __wl12xx_spi_raw_write(struct device *child, int addr,
  				  void *buf, size_t len, bool fixed)
  {
  	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  	struct spi_transfer *t;
  	struct spi_message m;
  	u32 commands[WSPI_MAX_NUM_OF_CHUNKS]; /* 1 command per chunk */
  	u32 *cmd;
  	u32 chunk_len;
  	int i;
  
  	/* SPI write buffers - 2 for each chunk */
  	t = kzalloc(sizeof(*t) * 2 * WSPI_MAX_NUM_OF_CHUNKS, GFP_KERNEL);
  	if (!t)
  		return -ENOMEM;
  
  	WARN_ON(len > SPI_AGGR_BUFFER_SIZE);
  
  	spi_message_init(&m);
  
  	cmd = &commands[0];
  	i = 0;
  	while (len > 0) {
  		chunk_len = min_t(size_t, WSPI_MAX_CHUNK_SIZE, len);
  
  		*cmd = 0;
  		*cmd |= WSPI_CMD_WRITE;
  		*cmd |= (chunk_len << WSPI_CMD_BYTE_LENGTH_OFFSET) &
  			WSPI_CMD_BYTE_LENGTH;
  		*cmd |= addr & WSPI_CMD_BYTE_ADDR;
  
  		if (fixed)
  			*cmd |= WSPI_CMD_FIXED;
  
  		t[i].tx_buf = cmd;
  		t[i].len = sizeof(*cmd);
  		spi_message_add_tail(&t[i++], &m);
  
  		t[i].tx_buf = buf;
  		t[i].len = chunk_len;
  		spi_message_add_tail(&t[i++], &m);
  
  		if (!fixed)
  			addr += chunk_len;
  		buf += chunk_len;
  		len -= chunk_len;
  		cmd++;
  	}
  
  	spi_sync(to_spi_device(glue->dev), &m);
  
  	kfree(t);
  	return 0;
  }
  
  static int __must_check wl12xx_spi_raw_write(struct device *child, int addr,
  					     void *buf, size_t len, bool fixed)
  {
  	/* The ELP wakeup write may fail the first time due to internal
  	 * hardware latency. It is safer to send the wakeup command twice to
  	 * avoid unexpected failures.
  	 */
  	if (addr == HW_ACCESS_ELP_CTRL_REG)
  		__wl12xx_spi_raw_write(child, addr, buf, len, fixed);
  
  	return __wl12xx_spi_raw_write(child, addr, buf, len, fixed);
  }
  
  /**
   * wl12xx_spi_set_power - power on/off the wl12xx unit
   * @child: wl12xx device handle.
   * @enable: true/false to power on/off the unit.
   *
   * use the WiFi enable regulator to enable/disable the WiFi unit.
   */
  static int wl12xx_spi_set_power(struct device *child, bool enable)
  {
  	int ret = 0;
  	struct wl12xx_spi_glue *glue = dev_get_drvdata(child->parent);
  
  	WARN_ON(!glue->reg);
  
  	/* Update regulator state */
  	if (enable) {
  		ret = regulator_enable(glue->reg);
  		if (ret)
  			dev_err(child, "Power enable failure\n");
  	} else {
  		ret =  regulator_disable(glue->reg);
  		if (ret)
  			dev_err(child, "Power disable failure\n");
  	}
  
  	return ret;
  }
  
  /*
   * wl12xx_spi_set_block_size
   *
   * This function is not needed for spi mode, but need to be present.
   * Without it defined the wlcore fallback to use the wrong packet
   * allignment on tx.
   */
  static void wl12xx_spi_set_block_size(struct device *child,
  				      unsigned int blksz)
  {
  }
  
  static struct wl1271_if_operations spi_ops = {
  	.read		= wl12xx_spi_raw_read,
  	.write		= wl12xx_spi_raw_write,
  	.reset		= wl12xx_spi_reset,
  	.init		= wl12xx_spi_init,
  	.power		= wl12xx_spi_set_power,
  	.set_block_size = wl12xx_spi_set_block_size,
  };
  
  static const struct of_device_id wlcore_spi_of_match_table[] = {
  	{ .compatible = "ti,wl1271", .data = &wl127x_data},
  	{ .compatible = "ti,wl1273", .data = &wl127x_data},
  	{ .compatible = "ti,wl1281", .data = &wl128x_data},
  	{ .compatible = "ti,wl1283", .data = &wl128x_data},
  	{ .compatible = "ti,wl1285", .data = &wl128x_data},
  	{ .compatible = "ti,wl1801", .data = &wl18xx_data},
  	{ .compatible = "ti,wl1805", .data = &wl18xx_data},
  	{ .compatible = "ti,wl1807", .data = &wl18xx_data},
  	{ .compatible = "ti,wl1831", .data = &wl18xx_data},
  	{ .compatible = "ti,wl1835", .data = &wl18xx_data},
  	{ .compatible = "ti,wl1837", .data = &wl18xx_data},
  	{ }
  };
  MODULE_DEVICE_TABLE(of, wlcore_spi_of_match_table);
  
  /**
   * wlcore_probe_of - DT node parsing.
   * @spi: SPI slave device parameters.
   * @glue: wl12xx SPI bus to slave device glue parameters.
   * @pdev_data: wlcore device parameters
   */
  static int wlcore_probe_of(struct spi_device *spi, struct wl12xx_spi_glue *glue,
  			   struct wlcore_platdev_data *pdev_data)
  {
  	struct device_node *dt_node = spi->dev.of_node;
  	const struct of_device_id *of_id;
  
  	of_id = of_match_node(wlcore_spi_of_match_table, dt_node);
  	if (!of_id)
  		return -ENODEV;
  
  	pdev_data->family = of_id->data;
  	dev_info(&spi->dev, "selected chip family is %s\n",
  		 pdev_data->family->name);
  
  	if (of_find_property(dt_node, "clock-xtal", NULL))
  		pdev_data->ref_clock_xtal = true;
  
  	/* optional clock frequency params */
  	of_property_read_u32(dt_node, "ref-clock-frequency",
  			     &pdev_data->ref_clock_freq);
  	of_property_read_u32(dt_node, "tcxo-clock-frequency",
  			     &pdev_data->tcxo_clock_freq);
  
  	return 0;
  }
  
  static int wl1271_probe(struct spi_device *spi)
  {
  	struct wl12xx_spi_glue *glue;
  	struct wlcore_platdev_data *pdev_data;
  	struct resource res[1];
  	int ret;
  
  	pdev_data = devm_kzalloc(&spi->dev, sizeof(*pdev_data), GFP_KERNEL);
  	if (!pdev_data)
  		return -ENOMEM;
  
  	pdev_data->if_ops = &spi_ops;
  
  	glue = devm_kzalloc(&spi->dev, sizeof(*glue), GFP_KERNEL);
  	if (!glue) {
  		dev_err(&spi->dev, "can't allocate glue\n");
  		return -ENOMEM;
  	}
  
  	glue->dev = &spi->dev;
  
  	spi_set_drvdata(spi, glue);
  
  	/* This is the only SPI value that we need to set here, the rest
  	 * comes from the board-peripherals file */
  	spi->bits_per_word = 32;
  
  	glue->reg = devm_regulator_get(&spi->dev, "vwlan");
  	if (IS_ERR(glue->reg))
  		return dev_err_probe(glue->dev, PTR_ERR(glue->reg),
  				     "can't get regulator\n");
  
  	ret = wlcore_probe_of(spi, glue, pdev_data);
  	if (ret) {
  		dev_err(glue->dev,
  			"can't get device tree parameters (%d)\n", ret);
  		return ret;
  	}
  
  	ret = spi_setup(spi);
  	if (ret < 0) {
  		dev_err(glue->dev, "spi_setup failed\n");
  		return ret;
  	}
  
  	glue->core = platform_device_alloc(pdev_data->family->name,
  					   PLATFORM_DEVID_AUTO);
  	if (!glue->core) {
  		dev_err(glue->dev, "can't allocate platform_device\n");
  		return -ENOMEM;
  	}
  
  	glue->core->dev.parent = &spi->dev;
  
  	memset(res, 0x00, sizeof(res));
  
  	res[0].start = spi->irq;
  	res[0].flags = IORESOURCE_IRQ | irq_get_trigger_type(spi->irq);
  	res[0].name = "irq";
  
  	ret = platform_device_add_resources(glue->core, res, ARRAY_SIZE(res));
  	if (ret) {
  		dev_err(glue->dev, "can't add resources\n");
  		goto out_dev_put;
  	}
  
  	ret = platform_device_add_data(glue->core, pdev_data,
  				       sizeof(*pdev_data));
  	if (ret) {
  		dev_err(glue->dev, "can't add platform data\n");
  		goto out_dev_put;
  	}
  
  	ret = platform_device_add(glue->core);
  	if (ret) {
  		dev_err(glue->dev, "can't register platform device\n");
  		goto out_dev_put;
  	}
  
  	return 0;
  
  out_dev_put:
  	platform_device_put(glue->core);
  	return ret;
  }
  
  static int wl1271_remove(struct spi_device *spi)
  {
  	struct wl12xx_spi_glue *glue = spi_get_drvdata(spi);
  
  	platform_device_unregister(glue->core);
  
  	return 0;
  }
  
  static struct spi_driver wl1271_spi_driver = {
  	.driver = {
  		.name		= "wl1271_spi",
  		.of_match_table = of_match_ptr(wlcore_spi_of_match_table),
  	},
  
  	.probe		= wl1271_probe,
  	.remove		= wl1271_remove,
  };
  
  module_spi_driver(wl1271_spi_driver);
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Luciano Coelho <coelho@ti.com>");
  MODULE_AUTHOR("Juuso Oikarinen <juuso.oikarinen@nokia.com>");
  MODULE_ALIAS("spi:wl1271");
  