/*
   * Copyright (C) 2010 - Maxim Levitsky
   * driver for Ricoh memstick readers
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  
  #include <linux/kernel.h>
  #include <linux/module.h>
  #include <linux/freezer.h>
  #include <linux/jiffies.h>
  #include <linux/interrupt.h>
  #include <linux/pci.h>
  #include <linux/pci_ids.h>
  #include <linux/delay.h>
  #include <linux/slab.h>
  #include <linux/kthread.h>
  #include <linux/sched.h>
  #include <linux/highmem.h>
  #include <asm/byteorder.h>
  #include <linux/swab.h>
  #include "r592.h"
  
  static bool r592_enable_dma = 1;
  static int debug;
  
  static const char *tpc_names[] = {
  	"MS_TPC_READ_MG_STATUS",
  	"MS_TPC_READ_LONG_DATA",
  	"MS_TPC_READ_SHORT_DATA",
  	"MS_TPC_READ_REG",
  	"MS_TPC_READ_QUAD_DATA",
  	"INVALID",
  	"MS_TPC_GET_INT",
  	"MS_TPC_SET_RW_REG_ADRS",
  	"MS_TPC_EX_SET_CMD",
  	"MS_TPC_WRITE_QUAD_DATA",
  	"MS_TPC_WRITE_REG",
  	"MS_TPC_WRITE_SHORT_DATA",
  	"MS_TPC_WRITE_LONG_DATA",
  	"MS_TPC_SET_CMD",
  };
  
  /**
   * memstick_debug_get_tpc_name - debug helper that returns string for
   * a TPC number
   */
  const char *memstick_debug_get_tpc_name(int tpc)
  {
  	return tpc_names[tpc-1];
  }
  EXPORT_SYMBOL(memstick_debug_get_tpc_name);
  
  
  /* Read a register*/
  static inline u32 r592_read_reg(struct r592_device *dev, int address)
  {
  	u32 value = readl(dev->mmio + address);
  	dbg_reg("reg #%02d == 0x%08x", address, value);
  	return value;
  }
  
  /* Write a register */
  static inline void r592_write_reg(struct r592_device *dev,
  							int address, u32 value)
  {
  	dbg_reg("reg #%02d <- 0x%08x", address, value);
  	writel(value, dev->mmio + address);
  }
  
  /* Reads a big endian DWORD register */
  static inline u32 r592_read_reg_raw_be(struct r592_device *dev, int address)
  {
  	u32 value = __raw_readl(dev->mmio + address);
  	dbg_reg("reg #%02d == 0x%08x", address, value);
  	return be32_to_cpu(value);
  }
  
  /* Writes a big endian DWORD register */
  static inline void r592_write_reg_raw_be(struct r592_device *dev,
  							int address, u32 value)
  {
  	dbg_reg("reg #%02d <- 0x%08x", address, value);
  	__raw_writel(cpu_to_be32(value), dev->mmio + address);
  }
  
  /* Set specific bits in a register (little endian) */
  static inline void r592_set_reg_mask(struct r592_device *dev,
  							int address, u32 mask)
  {
  	u32 reg = readl(dev->mmio + address);
  	dbg_reg("reg #%02d |= 0x%08x (old =0x%08x)", address, mask, reg);
  	writel(reg | mask , dev->mmio + address);
  }
  
  /* Clear specific bits in a register (little endian) */
  static inline void r592_clear_reg_mask(struct r592_device *dev,
  						int address, u32 mask)
  {
  	u32 reg = readl(dev->mmio + address);
  	dbg_reg("reg #%02d &= 0x%08x (old = 0x%08x, mask = 0x%08x)",
  						address, ~mask, reg, mask);
  	writel(reg & ~mask, dev->mmio + address);
  }
  
  
  /* Wait for status bits while checking for errors */
  static int r592_wait_status(struct r592_device *dev, u32 mask, u32 wanted_mask)
  {
  	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
  	u32 reg = r592_read_reg(dev, R592_STATUS);
  
  	if ((reg & mask) == wanted_mask)
  		return 0;
  
  	while (time_before(jiffies, timeout)) {
  
  		reg = r592_read_reg(dev, R592_STATUS);
  
  		if ((reg & mask) == wanted_mask)
  			return 0;
  
  		if (reg & (R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR))
  			return -EIO;
  
  		cpu_relax();
  	}
  	return -ETIME;
  }
  
  
  /* Enable/disable device */
  static int r592_enable_device(struct r592_device *dev, bool enable)
  {
  	dbg("%sabling the device", enable ? "en" : "dis");
  
  	if (enable) {
  
  		/* Power up the card */
  		r592_write_reg(dev, R592_POWER, R592_POWER_0 | R592_POWER_1);
  
  		/* Perform a reset */
  		r592_set_reg_mask(dev, R592_IO, R592_IO_RESET);
  
  		msleep(100);
  	} else
  		/* Power down the card */
  		r592_write_reg(dev, R592_POWER, 0);
  
  	return 0;
  }
  
  /* Set serial/parallel mode */
  static int r592_set_mode(struct r592_device *dev, bool parallel_mode)
  {
  	if (!parallel_mode) {
  		dbg("switching to serial mode");
  
  		/* Set serial mode */
  		r592_write_reg(dev, R592_IO_MODE, R592_IO_MODE_SERIAL);
  
  		r592_clear_reg_mask(dev, R592_POWER, R592_POWER_20);
  
  	} else {
  		dbg("switching to parallel mode");
  
  		/* This setting should be set _before_ switch TPC */
  		r592_set_reg_mask(dev, R592_POWER, R592_POWER_20);
  
  		r592_clear_reg_mask(dev, R592_IO,
  			R592_IO_SERIAL1 | R592_IO_SERIAL2);
  
  		/* Set the parallel mode now */
  		r592_write_reg(dev, R592_IO_MODE, R592_IO_MODE_PARALLEL);
  	}
  
  	dev->parallel_mode = parallel_mode;
  	return 0;
  }
  
  /* Perform a controller reset without powering down the card */
  static void r592_host_reset(struct r592_device *dev)
  {
  	r592_set_reg_mask(dev, R592_IO, R592_IO_RESET);
  	msleep(100);
  	r592_set_mode(dev, dev->parallel_mode);
  }
  
  /* Disable all hardware interrupts */
  static void r592_clear_interrupts(struct r592_device *dev)
  {
  	/* Disable & ACK all interrupts */
  	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_ACK_MASK);
  	r592_clear_reg_mask(dev, R592_REG_MSC, IRQ_ALL_EN_MASK);
  }
  
  /* Tests if there is an CRC error */
  static int r592_test_io_error(struct r592_device *dev)
  {
  	if (!(r592_read_reg(dev, R592_STATUS) &
  		(R592_STATUS_SEND_ERR | R592_STATUS_RECV_ERR)))
  		return 0;
  
  	return -EIO;
  }
  
  /* Ensure that FIFO is ready for use */
  static int r592_test_fifo_empty(struct r592_device *dev)
  {
  	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
  		return 0;
  
  	dbg("FIFO not ready, trying to reset the device");
  	r592_host_reset(dev);
  
  	if (r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_FIFO_EMPTY)
  		return 0;
  
  	message("FIFO still not ready, giving up");
  	return -EIO;
  }
  
  /* Activates the DMA transfer from to FIFO */
  static void r592_start_dma(struct r592_device *dev, bool is_write)
  {
  	unsigned long flags;
  	u32 reg;
  	spin_lock_irqsave(&dev->irq_lock, flags);
  
  	/* Ack interrupts (just in case) + enable them */
  	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
  	r592_set_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
  
  	/* Set DMA address */
  	r592_write_reg(dev, R592_FIFO_DMA, sg_dma_address(&dev->req->sg));
  
  	/* Enable the DMA */
  	reg = r592_read_reg(dev, R592_FIFO_DMA_SETTINGS);
  	reg |= R592_FIFO_DMA_SETTINGS_EN;
  
  	if (!is_write)
  		reg |= R592_FIFO_DMA_SETTINGS_DIR;
  	else
  		reg &= ~R592_FIFO_DMA_SETTINGS_DIR;
  	r592_write_reg(dev, R592_FIFO_DMA_SETTINGS, reg);
  
  	spin_unlock_irqrestore(&dev->irq_lock, flags);
  }
  
  /* Cleanups DMA related settings */
  static void r592_stop_dma(struct r592_device *dev, int error)
  {
  	r592_clear_reg_mask(dev, R592_FIFO_DMA_SETTINGS,
  		R592_FIFO_DMA_SETTINGS_EN);
  
  	/* This is only a precation */
  	r592_write_reg(dev, R592_FIFO_DMA,
  			dev->dummy_dma_page_physical_address);
  
  	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_EN_MASK);
  	r592_clear_reg_mask(dev, R592_REG_MSC, DMA_IRQ_ACK_MASK);
  	dev->dma_error = error;
  }
  
  /* Test if hardware supports DMA */
  static void r592_check_dma(struct r592_device *dev)
  {
  	dev->dma_capable = r592_enable_dma &&
  		(r592_read_reg(dev, R592_FIFO_DMA_SETTINGS) &
  			R592_FIFO_DMA_SETTINGS_CAP);
  }
  
  /* Transfers fifo contents in/out using DMA */
  static int r592_transfer_fifo_dma(struct r592_device *dev)
  {
  	int len, sg_count;
  	bool is_write;
  
  	if (!dev->dma_capable || !dev->req->long_data)
  		return -EINVAL;
  
  	len = dev->req->sg.length;
  	is_write = dev->req->data_dir == WRITE;
  
  	if (len != R592_LFIFO_SIZE)
  		return -EINVAL;
  
  	dbg_verbose("doing dma transfer");
  
  	dev->dma_error = 0;
  	reinit_completion(&dev->dma_done);
  
  	/* TODO: hidden assumption about nenth beeing always 1 */
  	sg_count = dma_map_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
  		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
  
  	if (sg_count != 1 ||
  			(sg_dma_len(&dev->req->sg) < dev->req->sg.length)) {
  		message("problem in dma_map_sg");
  		return -EIO;
  	}
  
  	r592_start_dma(dev, is_write);
  
  	/* Wait for DMA completion */
  	if (!wait_for_completion_timeout(
  			&dev->dma_done, msecs_to_jiffies(1000))) {
  		message("DMA timeout");
  		r592_stop_dma(dev, -ETIMEDOUT);
  	}
  
  	dma_unmap_sg(&dev->pci_dev->dev, &dev->req->sg, 1, is_write ?
  		PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
  
  
  	return dev->dma_error;
  }
  
  /*
   * Writes the FIFO in 4 byte chunks.
   * If length isn't 4 byte aligned, rest of the data if put to a fifo
   * to be written later
   * Use r592_flush_fifo_write to flush that fifo when writing for the
   * last time
   */
  static void r592_write_fifo_pio(struct r592_device *dev,
  					unsigned char *buffer, int len)
  {
  	/* flush spill from former write */
  	if (!kfifo_is_empty(&dev->pio_fifo)) {
  
  		u8 tmp[4] = {0};
  		int copy_len = kfifo_in(&dev->pio_fifo, buffer, len);
  
  		if (!kfifo_is_full(&dev->pio_fifo))
  			return;
  		len -= copy_len;
  		buffer += copy_len;
  
  		copy_len = kfifo_out(&dev->pio_fifo, tmp, 4);
  		WARN_ON(copy_len != 4);
  		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)tmp);
  	}
  
  	WARN_ON(!kfifo_is_empty(&dev->pio_fifo));
  
  	/* write full dwords */
  	while (len >= 4) {
  		r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
  		buffer += 4;
  		len -= 4;
  	}
  
  	/* put remaining bytes to the spill */
  	if (len)
  		kfifo_in(&dev->pio_fifo, buffer, len);
  }
  
  /* Flushes the temporary FIFO used to make aligned DWORD writes */
  static void r592_flush_fifo_write(struct r592_device *dev)
  {
  	u8 buffer[4] = { 0 };
  	int len;
  
  	if (kfifo_is_empty(&dev->pio_fifo))
  		return;
  
  	len = kfifo_out(&dev->pio_fifo, buffer, 4);
  	r592_write_reg_raw_be(dev, R592_FIFO_PIO, *(u32 *)buffer);
  }
  
  /*
   * Read a fifo in 4 bytes chunks.
   * If input doesn't fit the buffer, it places bytes of last dword in spill
   * buffer, so that they don't get lost on last read, just throw these away.
   */
  static void r592_read_fifo_pio(struct r592_device *dev,
  						unsigned char *buffer, int len)
  {
  	u8 tmp[4];
  
  	/* Read from last spill */
  	if (!kfifo_is_empty(&dev->pio_fifo)) {
  		int bytes_copied =
  			kfifo_out(&dev->pio_fifo, buffer, min(4, len));
  		buffer += bytes_copied;
  		len -= bytes_copied;
  
  		if (!kfifo_is_empty(&dev->pio_fifo))
  			return;
  	}
  
  	/* Reads dwords from FIFO */
  	while (len >= 4) {
  		*(u32 *)buffer = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
  		buffer += 4;
  		len -= 4;
  	}
  
  	if (len) {
  		*(u32 *)tmp = r592_read_reg_raw_be(dev, R592_FIFO_PIO);
  		kfifo_in(&dev->pio_fifo, tmp, 4);
  		len -= kfifo_out(&dev->pio_fifo, buffer, len);
  	}
  
  	WARN_ON(len);
  	return;
  }
  
  /* Transfers actual data using PIO. */
  static int r592_transfer_fifo_pio(struct r592_device *dev)
  {
  	unsigned long flags;
  
  	bool is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
  	struct sg_mapping_iter miter;
  
  	kfifo_reset(&dev->pio_fifo);
  
  	if (!dev->req->long_data) {
  		if (is_write) {
  			r592_write_fifo_pio(dev, dev->req->data,
  							dev->req->data_len);
  			r592_flush_fifo_write(dev);
  		} else
  			r592_read_fifo_pio(dev, dev->req->data,
  							dev->req->data_len);
  		return 0;
  	}
  
  	local_irq_save(flags);
  	sg_miter_start(&miter, &dev->req->sg, 1, SG_MITER_ATOMIC |
  		(is_write ? SG_MITER_FROM_SG : SG_MITER_TO_SG));
  
  	/* Do the transfer fifo<->memory*/
  	while (sg_miter_next(&miter))
  		if (is_write)
  			r592_write_fifo_pio(dev, miter.addr, miter.length);
  		else
  			r592_read_fifo_pio(dev, miter.addr, miter.length);
  
  
  	/* Write last few non aligned bytes*/
  	if (is_write)
  		r592_flush_fifo_write(dev);
  
  	sg_miter_stop(&miter);
  	local_irq_restore(flags);
  	return 0;
  }
  
  /* Executes one TPC (data is read/written from small or large fifo) */
  static void r592_execute_tpc(struct r592_device *dev)
  {
  	bool is_write;
  	int len, error;
  	u32 status, reg;
  
  	if (!dev->req) {
  		message("BUG: tpc execution without request!");
  		return;
  	}
  
  	is_write = dev->req->tpc >= MS_TPC_SET_RW_REG_ADRS;
  	len = dev->req->long_data ?
  		dev->req->sg.length : dev->req->data_len;
  
  	/* Ensure that FIFO can hold the input data */
  	if (len > R592_LFIFO_SIZE) {
  		message("IO: hardware doesn't support TPCs longer that 512");
  		error = -ENOSYS;
  		goto out;
  	}
  
  	if (!(r592_read_reg(dev, R592_REG_MSC) & R592_REG_MSC_PRSNT)) {
  		dbg("IO: refusing to send TPC because card is absent");
  		error = -ENODEV;
  		goto out;
  	}
  
  	dbg("IO: executing %s LEN=%d",
  			memstick_debug_get_tpc_name(dev->req->tpc), len);
  
  	/* Set IO direction */
  	if (is_write)
  		r592_set_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
  	else
  		r592_clear_reg_mask(dev, R592_IO, R592_IO_DIRECTION);
  
  
  	error = r592_test_fifo_empty(dev);
  	if (error)
  		goto out;
  
  	/* Transfer write data */
  	if (is_write) {
  		error = r592_transfer_fifo_dma(dev);
  		if (error == -EINVAL)
  			error = r592_transfer_fifo_pio(dev);
  	}
  
  	if (error)
  		goto out;
  
  	/* Trigger the TPC */
  	reg = (len << R592_TPC_EXEC_LEN_SHIFT) |
  		(dev->req->tpc << R592_TPC_EXEC_TPC_SHIFT) |
  			R592_TPC_EXEC_BIG_FIFO;
  
  	r592_write_reg(dev, R592_TPC_EXEC, reg);
  
  	/* Wait for TPC completion */
  	status = R592_STATUS_RDY;
  	if (dev->req->need_card_int)
  		status |= R592_STATUS_CED;
  
  	error = r592_wait_status(dev, status, status);
  	if (error) {
  		message("card didn't respond");
  		goto out;
  	}
  
  	/* Test IO errors */
  	error = r592_test_io_error(dev);
  	if (error) {
  		dbg("IO error");
  		goto out;
  	}
  
  	/* Read data from FIFO */
  	if (!is_write) {
  		error = r592_transfer_fifo_dma(dev);
  		if (error == -EINVAL)
  			error = r592_transfer_fifo_pio(dev);
  	}
  
  	/* read INT reg. This can be shortened with shifts, but that way
  		its more readable */
  	if (dev->parallel_mode && dev->req->need_card_int) {
  
  		dev->req->int_reg = 0;
  		status = r592_read_reg(dev, R592_STATUS);
  
  		if (status & R592_STATUS_P_CMDNACK)
  			dev->req->int_reg |= MEMSTICK_INT_CMDNAK;
  		if (status & R592_STATUS_P_BREQ)
  			dev->req->int_reg |= MEMSTICK_INT_BREQ;
  		if (status & R592_STATUS_P_INTERR)
  			dev->req->int_reg |= MEMSTICK_INT_ERR;
  		if (status & R592_STATUS_P_CED)
  			dev->req->int_reg |= MEMSTICK_INT_CED;
  	}
  
  	if (error)
  		dbg("FIFO read error");
  out:
  	dev->req->error = error;
  	r592_clear_reg_mask(dev, R592_REG_MSC, R592_REG_MSC_LED);
  	return;
  }
  
  /* Main request processing thread */
  static int r592_process_thread(void *data)
  {
  	int error;
  	struct r592_device *dev = (struct r592_device *)data;
  	unsigned long flags;
  
  	while (!kthread_should_stop()) {
  		spin_lock_irqsave(&dev->io_thread_lock, flags);
  		set_current_state(TASK_INTERRUPTIBLE);
  		error = memstick_next_req(dev->host, &dev->req);
  		spin_unlock_irqrestore(&dev->io_thread_lock, flags);
  
  		if (error) {
  			if (error == -ENXIO || error == -EAGAIN) {
  				dbg_verbose("IO: done IO, sleeping");
  			} else {
  				dbg("IO: unknown error from "
  					"memstick_next_req %d", error);
  			}
  
  			if (kthread_should_stop())
  				set_current_state(TASK_RUNNING);
  
  			schedule();
  		} else {
  			set_current_state(TASK_RUNNING);
  			r592_execute_tpc(dev);
  		}
  	}
  	return 0;
  }
  
  /* Reprogram chip to detect change in card state */
  /* eg, if card is detected, arm it to detect removal, and vice versa */
  static void r592_update_card_detect(struct r592_device *dev)
  {
  	u32 reg = r592_read_reg(dev, R592_REG_MSC);
  	bool card_detected = reg & R592_REG_MSC_PRSNT;
  
  	dbg("update card detect. card state: %s", card_detected ?
  		"present" : "absent");
  
  	reg &= ~((R592_REG_MSC_IRQ_REMOVE | R592_REG_MSC_IRQ_INSERT) << 16);
  
  	if (card_detected)
  		reg |= (R592_REG_MSC_IRQ_REMOVE << 16);
  	else
  		reg |= (R592_REG_MSC_IRQ_INSERT << 16);
  
  	r592_write_reg(dev, R592_REG_MSC, reg);
  }
  
  /* Timer routine that fires 1 second after last card detection event, */
  static void r592_detect_timer(long unsigned int data)
  {
  	struct r592_device *dev = (struct r592_device *)data;
  	r592_update_card_detect(dev);
  	memstick_detect_change(dev->host);
  }
  
  /* Interrupt handler */
  static irqreturn_t r592_irq(int irq, void *data)
  {
  	struct r592_device *dev = (struct r592_device *)data;
  	irqreturn_t ret = IRQ_NONE;
  	u32 reg;
  	u16 irq_enable, irq_status;
  	unsigned long flags;
  	int error;
  
  	spin_lock_irqsave(&dev->irq_lock, flags);
  
  	reg = r592_read_reg(dev, R592_REG_MSC);
  	irq_enable = reg >> 16;
  	irq_status = reg & 0xFFFF;
  
  	/* Ack the interrupts */
  	reg &= ~irq_status;
  	r592_write_reg(dev, R592_REG_MSC, reg);
  
  	/* Get the IRQ status minus bits that aren't enabled */
  	irq_status &= (irq_enable);
  
  	/* Due to limitation of memstick core, we don't look at bits that
  		indicate that card was removed/inserted and/or present */
  	if (irq_status & (R592_REG_MSC_IRQ_INSERT | R592_REG_MSC_IRQ_REMOVE)) {
  
  		bool card_was_added = irq_status & R592_REG_MSC_IRQ_INSERT;
  		ret = IRQ_HANDLED;
  
  		message("IRQ: card %s", card_was_added ? "added" : "removed");
  
  		mod_timer(&dev->detect_timer,
  			jiffies + msecs_to_jiffies(card_was_added ? 500 : 50));
  	}
  
  	if (irq_status &
  		(R592_REG_MSC_FIFO_DMA_DONE | R592_REG_MSC_FIFO_DMA_ERR)) {
  		ret = IRQ_HANDLED;
  
  		if (irq_status & R592_REG_MSC_FIFO_DMA_ERR) {
  			message("IRQ: DMA error");
  			error = -EIO;
  		} else {
  			dbg_verbose("IRQ: dma done");
  			error = 0;
  		}
  
  		r592_stop_dma(dev, error);
  		complete(&dev->dma_done);
  	}
  
  	spin_unlock_irqrestore(&dev->irq_lock, flags);
  	return ret;
  }
  
  /* External inteface: set settings */
  static int r592_set_param(struct memstick_host *host,
  			enum memstick_param param, int value)
  {
  	struct r592_device *dev = memstick_priv(host);
  
  	switch (param) {
  	case MEMSTICK_POWER:
  		switch (value) {
  		case MEMSTICK_POWER_ON:
  			return r592_enable_device(dev, true);
  		case MEMSTICK_POWER_OFF:
  			return r592_enable_device(dev, false);
  		default:
  			return -EINVAL;
  		}
  	case MEMSTICK_INTERFACE:
  		switch (value) {
  		case MEMSTICK_SERIAL:
  			return r592_set_mode(dev, 0);
  		case MEMSTICK_PAR4:
  			return r592_set_mode(dev, 1);
  		default:
  			return -EINVAL;
  		}
  	default:
  		return -EINVAL;
  	}
  }
  
  /* External interface: submit requests */
  static void r592_submit_req(struct memstick_host *host)
  {
  	struct r592_device *dev = memstick_priv(host);
  	unsigned long flags;
  
  	if (dev->req)
  		return;
  
  	spin_lock_irqsave(&dev->io_thread_lock, flags);
  	if (wake_up_process(dev->io_thread))
  		dbg_verbose("IO thread woken to process requests");
  	spin_unlock_irqrestore(&dev->io_thread_lock, flags);
  }
  
  static const struct pci_device_id r592_pci_id_tbl[] = {
  
  	{ PCI_VDEVICE(RICOH, 0x0592), },
  	{ },
  };
  
  /* Main entry */
  static int r592_probe(struct pci_dev *pdev, const struct pci_device_id *id)
  {
  	int error = -ENOMEM;
  	struct memstick_host *host;
  	struct r592_device *dev;
  
  	/* Allocate memory */
  	host = memstick_alloc_host(sizeof(struct r592_device), &pdev->dev);
  	if (!host)
  		goto error1;
  
  	dev = memstick_priv(host);
  	dev->host = host;
  	dev->pci_dev = pdev;
  	pci_set_drvdata(pdev, dev);
  
  	/* pci initialization */
  	error = pci_enable_device(pdev);
  	if (error)
  		goto error2;
  
  	pci_set_master(pdev);
  	error = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
  	if (error)
  		goto error3;
  
  	error = pci_request_regions(pdev, DRV_NAME);
  	if (error)
  		goto error3;
  
  	dev->mmio = pci_ioremap_bar(pdev, 0);
  	if (!dev->mmio)
  		goto error4;
  
  	dev->irq = pdev->irq;
  	spin_lock_init(&dev->irq_lock);
  	spin_lock_init(&dev->io_thread_lock);
  	init_completion(&dev->dma_done);
  	INIT_KFIFO(dev->pio_fifo);
  	setup_timer(&dev->detect_timer,
  		r592_detect_timer, (long unsigned int)dev);
  
  	/* Host initialization */
  	host->caps = MEMSTICK_CAP_PAR4;
  	host->request = r592_submit_req;
  	host->set_param = r592_set_param;
  	r592_check_dma(dev);
  
  	dev->io_thread = kthread_run(r592_process_thread, dev, "r592_io");
  	if (IS_ERR(dev->io_thread)) {
  		error = PTR_ERR(dev->io_thread);
  		goto error5;
  	}
  
  	/* This is just a precation, so don't fail */
  	dev->dummy_dma_page = pci_alloc_consistent(pdev, PAGE_SIZE,
  		&dev->dummy_dma_page_physical_address);
  	r592_stop_dma(dev , 0);
  
  	if (request_irq(dev->irq, &r592_irq, IRQF_SHARED,
  			  DRV_NAME, dev))
  		goto error6;
  
  	r592_update_card_detect(dev);
  	if (memstick_add_host(host))
  		goto error7;
  
  	message("driver successfully loaded");
  	return 0;
  error7:
  	free_irq(dev->irq, dev);
  error6:
  	if (dev->dummy_dma_page)
  		pci_free_consistent(pdev, PAGE_SIZE, dev->dummy_dma_page,
  			dev->dummy_dma_page_physical_address);
  
  	kthread_stop(dev->io_thread);
  error5:
  	iounmap(dev->mmio);
  error4:
  	pci_release_regions(pdev);
  error3:
  	pci_disable_device(pdev);
  error2:
  	memstick_free_host(host);
  error1:
  	return error;
  }
  
  static void r592_remove(struct pci_dev *pdev)
  {
  	int error = 0;
  	struct r592_device *dev = pci_get_drvdata(pdev);
  
  	/* Stop the processing thread.
  	That ensures that we won't take any more requests */
  	kthread_stop(dev->io_thread);
  
  	r592_enable_device(dev, false);
  
  	while (!error && dev->req) {
  		dev->req->error = -ETIME;
  		error = memstick_next_req(dev->host, &dev->req);
  	}
  	memstick_remove_host(dev->host);
  
  	free_irq(dev->irq, dev);
  	iounmap(dev->mmio);
  	pci_release_regions(pdev);
  	pci_disable_device(pdev);
  	memstick_free_host(dev->host);
  
  	if (dev->dummy_dma_page)
  		pci_free_consistent(pdev, PAGE_SIZE, dev->dummy_dma_page,
  			dev->dummy_dma_page_physical_address);
  }
  
  #ifdef CONFIG_PM_SLEEP
  static int r592_suspend(struct device *core_dev)
  {
  	struct pci_dev *pdev = to_pci_dev(core_dev);
  	struct r592_device *dev = pci_get_drvdata(pdev);
  
  	r592_clear_interrupts(dev);
  	memstick_suspend_host(dev->host);
  	del_timer_sync(&dev->detect_timer);
  	return 0;
  }
  
  static int r592_resume(struct device *core_dev)
  {
  	struct pci_dev *pdev = to_pci_dev(core_dev);
  	struct r592_device *dev = pci_get_drvdata(pdev);
  
  	r592_clear_interrupts(dev);
  	r592_enable_device(dev, false);
  	memstick_resume_host(dev->host);
  	r592_update_card_detect(dev);
  	return 0;
  }
  #endif
  
  static SIMPLE_DEV_PM_OPS(r592_pm_ops, r592_suspend, r592_resume);
  
  MODULE_DEVICE_TABLE(pci, r592_pci_id_tbl);
  
  static struct pci_driver r852_pci_driver = {
  	.name		= DRV_NAME,
  	.id_table	= r592_pci_id_tbl,
  	.probe		= r592_probe,
  	.remove		= r592_remove,
  	.driver.pm	= &r592_pm_ops,
  };
  
  module_pci_driver(r852_pci_driver);
  
  module_param_named(enable_dma, r592_enable_dma, bool, S_IRUGO);
  MODULE_PARM_DESC(enable_dma, "Enable usage of the DMA (default)");
  module_param(debug, int, S_IRUGO | S_IWUSR);
  MODULE_PARM_DESC(debug, "Debug level (0-3)");
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
  MODULE_DESCRIPTION("Ricoh R5C592 Memstick/Memstick PRO card reader driver");