spi: reorganize drivers
Sort the SPI makefile and enforce the naming convention spi_*.c for
spi drivers.
This change also rolls the contents of atmel_spi.h into the .c file
since there is only one user of that particular include file.
v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be
be the predominant pattern for subsystem prefixes.
- Clean up filenames in Kconfig and header comment blocks
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/spi/spi-dw.c b/drivers/spi/spi-dw.c
new file mode 100644
index 0000000..ece5f69
--- /dev/null
+++ b/drivers/spi/spi-dw.c
@@ -0,0 +1,936 @@
+/*
+ * Designware SPI core controller driver (refer pxa2xx_spi.c)
+ *
+ * Copyright (c) 2009, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/highmem.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+
+#include "spi-dw.h"
+
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+#endif
+
+#define START_STATE ((void *)0)
+#define RUNNING_STATE ((void *)1)
+#define DONE_STATE ((void *)2)
+#define ERROR_STATE ((void *)-1)
+
+#define QUEUE_RUNNING 0
+#define QUEUE_STOPPED 1
+
+#define MRST_SPI_DEASSERT 0
+#define MRST_SPI_ASSERT 1
+
+/* Slave spi_dev related */
+struct chip_data {
+ u16 cr0;
+ u8 cs; /* chip select pin */
+ u8 n_bytes; /* current is a 1/2/4 byte op */
+ u8 tmode; /* TR/TO/RO/EEPROM */
+ u8 type; /* SPI/SSP/MicroWire */
+
+ u8 poll_mode; /* 1 means use poll mode */
+
+ u32 dma_width;
+ u32 rx_threshold;
+ u32 tx_threshold;
+ u8 enable_dma;
+ u8 bits_per_word;
+ u16 clk_div; /* baud rate divider */
+ u32 speed_hz; /* baud rate */
+ void (*cs_control)(u32 command);
+};
+
+#ifdef CONFIG_DEBUG_FS
+static int spi_show_regs_open(struct inode *inode, struct file *file)
+{
+ file->private_data = inode->i_private;
+ return 0;
+}
+
+#define SPI_REGS_BUFSIZE 1024
+static ssize_t spi_show_regs(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct dw_spi *dws;
+ char *buf;
+ u32 len = 0;
+ ssize_t ret;
+
+ dws = file->private_data;
+
+ buf = kzalloc(SPI_REGS_BUFSIZE, GFP_KERNEL);
+ if (!buf)
+ return 0;
+
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "MRST SPI0 registers:\n");
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "=================================\n");
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "CTRL0: \t\t0x%08x\n", dw_readl(dws, ctrl0));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "CTRL1: \t\t0x%08x\n", dw_readl(dws, ctrl1));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "SSIENR: \t0x%08x\n", dw_readl(dws, ssienr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "SER: \t\t0x%08x\n", dw_readl(dws, ser));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "BAUDR: \t\t0x%08x\n", dw_readl(dws, baudr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "TXFTLR: \t0x%08x\n", dw_readl(dws, txfltr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "RXFTLR: \t0x%08x\n", dw_readl(dws, rxfltr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "TXFLR: \t\t0x%08x\n", dw_readl(dws, txflr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "RXFLR: \t\t0x%08x\n", dw_readl(dws, rxflr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "SR: \t\t0x%08x\n", dw_readl(dws, sr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "IMR: \t\t0x%08x\n", dw_readl(dws, imr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "ISR: \t\t0x%08x\n", dw_readl(dws, isr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "DMACR: \t\t0x%08x\n", dw_readl(dws, dmacr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "DMATDLR: \t0x%08x\n", dw_readl(dws, dmatdlr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "DMARDLR: \t0x%08x\n", dw_readl(dws, dmardlr));
+ len += snprintf(buf + len, SPI_REGS_BUFSIZE - len,
+ "=================================\n");
+
+ ret = simple_read_from_buffer(user_buf, count, ppos, buf, len);
+ kfree(buf);
+ return ret;
+}
+
+static const struct file_operations mrst_spi_regs_ops = {
+ .owner = THIS_MODULE,
+ .open = spi_show_regs_open,
+ .read = spi_show_regs,
+ .llseek = default_llseek,
+};
+
+static int mrst_spi_debugfs_init(struct dw_spi *dws)
+{
+ dws->debugfs = debugfs_create_dir("mrst_spi", NULL);
+ if (!dws->debugfs)
+ return -ENOMEM;
+
+ debugfs_create_file("registers", S_IFREG | S_IRUGO,
+ dws->debugfs, (void *)dws, &mrst_spi_regs_ops);
+ return 0;
+}
+
+static void mrst_spi_debugfs_remove(struct dw_spi *dws)
+{
+ if (dws->debugfs)
+ debugfs_remove_recursive(dws->debugfs);
+}
+
+#else
+static inline int mrst_spi_debugfs_init(struct dw_spi *dws)
+{
+ return 0;
+}
+
+static inline void mrst_spi_debugfs_remove(struct dw_spi *dws)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
+/* Return the max entries we can fill into tx fifo */
+static inline u32 tx_max(struct dw_spi *dws)
+{
+ u32 tx_left, tx_room, rxtx_gap;
+
+ tx_left = (dws->tx_end - dws->tx) / dws->n_bytes;
+ tx_room = dws->fifo_len - dw_readw(dws, txflr);
+
+ /*
+ * Another concern is about the tx/rx mismatch, we
+ * though to use (dws->fifo_len - rxflr - txflr) as
+ * one maximum value for tx, but it doesn't cover the
+ * data which is out of tx/rx fifo and inside the
+ * shift registers. So a control from sw point of
+ * view is taken.
+ */
+ rxtx_gap = ((dws->rx_end - dws->rx) - (dws->tx_end - dws->tx))
+ / dws->n_bytes;
+
+ return min3(tx_left, tx_room, (u32) (dws->fifo_len - rxtx_gap));
+}
+
+/* Return the max entries we should read out of rx fifo */
+static inline u32 rx_max(struct dw_spi *dws)
+{
+ u32 rx_left = (dws->rx_end - dws->rx) / dws->n_bytes;
+
+ return min(rx_left, (u32)dw_readw(dws, rxflr));
+}
+
+static void dw_writer(struct dw_spi *dws)
+{
+ u32 max = tx_max(dws);
+ u16 txw = 0;
+
+ while (max--) {
+ /* Set the tx word if the transfer's original "tx" is not null */
+ if (dws->tx_end - dws->len) {
+ if (dws->n_bytes == 1)
+ txw = *(u8 *)(dws->tx);
+ else
+ txw = *(u16 *)(dws->tx);
+ }
+ dw_writew(dws, dr, txw);
+ dws->tx += dws->n_bytes;
+ }
+}
+
+static void dw_reader(struct dw_spi *dws)
+{
+ u32 max = rx_max(dws);
+ u16 rxw;
+
+ while (max--) {
+ rxw = dw_readw(dws, dr);
+ /* Care rx only if the transfer's original "rx" is not null */
+ if (dws->rx_end - dws->len) {
+ if (dws->n_bytes == 1)
+ *(u8 *)(dws->rx) = rxw;
+ else
+ *(u16 *)(dws->rx) = rxw;
+ }
+ dws->rx += dws->n_bytes;
+ }
+}
+
+static void *next_transfer(struct dw_spi *dws)
+{
+ struct spi_message *msg = dws->cur_msg;
+ struct spi_transfer *trans = dws->cur_transfer;
+
+ /* Move to next transfer */
+ if (trans->transfer_list.next != &msg->transfers) {
+ dws->cur_transfer =
+ list_entry(trans->transfer_list.next,
+ struct spi_transfer,
+ transfer_list);
+ return RUNNING_STATE;
+ } else
+ return DONE_STATE;
+}
+
+/*
+ * Note: first step is the protocol driver prepares
+ * a dma-capable memory, and this func just need translate
+ * the virt addr to physical
+ */
+static int map_dma_buffers(struct dw_spi *dws)
+{
+ if (!dws->cur_msg->is_dma_mapped
+ || !dws->dma_inited
+ || !dws->cur_chip->enable_dma
+ || !dws->dma_ops)
+ return 0;
+
+ if (dws->cur_transfer->tx_dma)
+ dws->tx_dma = dws->cur_transfer->tx_dma;
+
+ if (dws->cur_transfer->rx_dma)
+ dws->rx_dma = dws->cur_transfer->rx_dma;
+
+ return 1;
+}
+
+/* Caller already set message->status; dma and pio irqs are blocked */
+static void giveback(struct dw_spi *dws)
+{
+ struct spi_transfer *last_transfer;
+ unsigned long flags;
+ struct spi_message *msg;
+
+ spin_lock_irqsave(&dws->lock, flags);
+ msg = dws->cur_msg;
+ dws->cur_msg = NULL;
+ dws->cur_transfer = NULL;
+ dws->prev_chip = dws->cur_chip;
+ dws->cur_chip = NULL;
+ dws->dma_mapped = 0;
+ queue_work(dws->workqueue, &dws->pump_messages);
+ spin_unlock_irqrestore(&dws->lock, flags);
+
+ last_transfer = list_entry(msg->transfers.prev,
+ struct spi_transfer,
+ transfer_list);
+
+ if (!last_transfer->cs_change && dws->cs_control)
+ dws->cs_control(MRST_SPI_DEASSERT);
+
+ msg->state = NULL;
+ if (msg->complete)
+ msg->complete(msg->context);
+}
+
+static void int_error_stop(struct dw_spi *dws, const char *msg)
+{
+ /* Stop the hw */
+ spi_enable_chip(dws, 0);
+
+ dev_err(&dws->master->dev, "%s\n", msg);
+ dws->cur_msg->state = ERROR_STATE;
+ tasklet_schedule(&dws->pump_transfers);
+}
+
+void dw_spi_xfer_done(struct dw_spi *dws)
+{
+ /* Update total byte transferred return count actual bytes read */
+ dws->cur_msg->actual_length += dws->len;
+
+ /* Move to next transfer */
+ dws->cur_msg->state = next_transfer(dws);
+
+ /* Handle end of message */
+ if (dws->cur_msg->state == DONE_STATE) {
+ dws->cur_msg->status = 0;
+ giveback(dws);
+ } else
+ tasklet_schedule(&dws->pump_transfers);
+}
+EXPORT_SYMBOL_GPL(dw_spi_xfer_done);
+
+static irqreturn_t interrupt_transfer(struct dw_spi *dws)
+{
+ u16 irq_status = dw_readw(dws, isr);
+
+ /* Error handling */
+ if (irq_status & (SPI_INT_TXOI | SPI_INT_RXOI | SPI_INT_RXUI)) {
+ dw_readw(dws, txoicr);
+ dw_readw(dws, rxoicr);
+ dw_readw(dws, rxuicr);
+ int_error_stop(dws, "interrupt_transfer: fifo overrun/underrun");
+ return IRQ_HANDLED;
+ }
+
+ dw_reader(dws);
+ if (dws->rx_end == dws->rx) {
+ spi_mask_intr(dws, SPI_INT_TXEI);
+ dw_spi_xfer_done(dws);
+ return IRQ_HANDLED;
+ }
+ if (irq_status & SPI_INT_TXEI) {
+ spi_mask_intr(dws, SPI_INT_TXEI);
+ dw_writer(dws);
+ /* Enable TX irq always, it will be disabled when RX finished */
+ spi_umask_intr(dws, SPI_INT_TXEI);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t dw_spi_irq(int irq, void *dev_id)
+{
+ struct dw_spi *dws = dev_id;
+ u16 irq_status = dw_readw(dws, isr) & 0x3f;
+
+ if (!irq_status)
+ return IRQ_NONE;
+
+ if (!dws->cur_msg) {
+ spi_mask_intr(dws, SPI_INT_TXEI);
+ return IRQ_HANDLED;
+ }
+
+ return dws->transfer_handler(dws);
+}
+
+/* Must be called inside pump_transfers() */
+static void poll_transfer(struct dw_spi *dws)
+{
+ do {
+ dw_writer(dws);
+ dw_reader(dws);
+ cpu_relax();
+ } while (dws->rx_end > dws->rx);
+
+ dw_spi_xfer_done(dws);
+}
+
+static void pump_transfers(unsigned long data)
+{
+ struct dw_spi *dws = (struct dw_spi *)data;
+ struct spi_message *message = NULL;
+ struct spi_transfer *transfer = NULL;
+ struct spi_transfer *previous = NULL;
+ struct spi_device *spi = NULL;
+ struct chip_data *chip = NULL;
+ u8 bits = 0;
+ u8 imask = 0;
+ u8 cs_change = 0;
+ u16 txint_level = 0;
+ u16 clk_div = 0;
+ u32 speed = 0;
+ u32 cr0 = 0;
+
+ /* Get current state information */
+ message = dws->cur_msg;
+ transfer = dws->cur_transfer;
+ chip = dws->cur_chip;
+ spi = message->spi;
+
+ if (unlikely(!chip->clk_div))
+ chip->clk_div = dws->max_freq / chip->speed_hz;
+
+ if (message->state == ERROR_STATE) {
+ message->status = -EIO;
+ goto early_exit;
+ }
+
+ /* Handle end of message */
+ if (message->state == DONE_STATE) {
+ message->status = 0;
+ goto early_exit;
+ }
+
+ /* Delay if requested at end of transfer*/
+ if (message->state == RUNNING_STATE) {
+ previous = list_entry(transfer->transfer_list.prev,
+ struct spi_transfer,
+ transfer_list);
+ if (previous->delay_usecs)
+ udelay(previous->delay_usecs);
+ }
+
+ dws->n_bytes = chip->n_bytes;
+ dws->dma_width = chip->dma_width;
+ dws->cs_control = chip->cs_control;
+
+ dws->rx_dma = transfer->rx_dma;
+ dws->tx_dma = transfer->tx_dma;
+ dws->tx = (void *)transfer->tx_buf;
+ dws->tx_end = dws->tx + transfer->len;
+ dws->rx = transfer->rx_buf;
+ dws->rx_end = dws->rx + transfer->len;
+ dws->cs_change = transfer->cs_change;
+ dws->len = dws->cur_transfer->len;
+ if (chip != dws->prev_chip)
+ cs_change = 1;
+
+ cr0 = chip->cr0;
+
+ /* Handle per transfer options for bpw and speed */
+ if (transfer->speed_hz) {
+ speed = chip->speed_hz;
+
+ if (transfer->speed_hz != speed) {
+ speed = transfer->speed_hz;
+ if (speed > dws->max_freq) {
+ printk(KERN_ERR "MRST SPI0: unsupported"
+ "freq: %dHz\n", speed);
+ message->status = -EIO;
+ goto early_exit;
+ }
+
+ /* clk_div doesn't support odd number */
+ clk_div = dws->max_freq / speed;
+ clk_div = (clk_div + 1) & 0xfffe;
+
+ chip->speed_hz = speed;
+ chip->clk_div = clk_div;
+ }
+ }
+ if (transfer->bits_per_word) {
+ bits = transfer->bits_per_word;
+
+ switch (bits) {
+ case 8:
+ case 16:
+ dws->n_bytes = dws->dma_width = bits >> 3;
+ break;
+ default:
+ printk(KERN_ERR "MRST SPI0: unsupported bits:"
+ "%db\n", bits);
+ message->status = -EIO;
+ goto early_exit;
+ }
+
+ cr0 = (bits - 1)
+ | (chip->type << SPI_FRF_OFFSET)
+ | (spi->mode << SPI_MODE_OFFSET)
+ | (chip->tmode << SPI_TMOD_OFFSET);
+ }
+ message->state = RUNNING_STATE;
+
+ /*
+ * Adjust transfer mode if necessary. Requires platform dependent
+ * chipselect mechanism.
+ */
+ if (dws->cs_control) {
+ if (dws->rx && dws->tx)
+ chip->tmode = SPI_TMOD_TR;
+ else if (dws->rx)
+ chip->tmode = SPI_TMOD_RO;
+ else
+ chip->tmode = SPI_TMOD_TO;
+
+ cr0 &= ~SPI_TMOD_MASK;
+ cr0 |= (chip->tmode << SPI_TMOD_OFFSET);
+ }
+
+ /* Check if current transfer is a DMA transaction */
+ dws->dma_mapped = map_dma_buffers(dws);
+
+ /*
+ * Interrupt mode
+ * we only need set the TXEI IRQ, as TX/RX always happen syncronizely
+ */
+ if (!dws->dma_mapped && !chip->poll_mode) {
+ int templen = dws->len / dws->n_bytes;
+ txint_level = dws->fifo_len / 2;
+ txint_level = (templen > txint_level) ? txint_level : templen;
+
+ imask |= SPI_INT_TXEI | SPI_INT_TXOI | SPI_INT_RXUI | SPI_INT_RXOI;
+ dws->transfer_handler = interrupt_transfer;
+ }
+
+ /*
+ * Reprogram registers only if
+ * 1. chip select changes
+ * 2. clk_div is changed
+ * 3. control value changes
+ */
+ if (dw_readw(dws, ctrl0) != cr0 || cs_change || clk_div || imask) {
+ spi_enable_chip(dws, 0);
+
+ if (dw_readw(dws, ctrl0) != cr0)
+ dw_writew(dws, ctrl0, cr0);
+
+ spi_set_clk(dws, clk_div ? clk_div : chip->clk_div);
+ spi_chip_sel(dws, spi->chip_select);
+
+ /* Set the interrupt mask, for poll mode just disable all int */
+ spi_mask_intr(dws, 0xff);
+ if (imask)
+ spi_umask_intr(dws, imask);
+ if (txint_level)
+ dw_writew(dws, txfltr, txint_level);
+
+ spi_enable_chip(dws, 1);
+ if (cs_change)
+ dws->prev_chip = chip;
+ }
+
+ if (dws->dma_mapped)
+ dws->dma_ops->dma_transfer(dws, cs_change);
+
+ if (chip->poll_mode)
+ poll_transfer(dws);
+
+ return;
+
+early_exit:
+ giveback(dws);
+ return;
+}
+
+static void pump_messages(struct work_struct *work)
+{
+ struct dw_spi *dws =
+ container_of(work, struct dw_spi, pump_messages);
+ unsigned long flags;
+
+ /* Lock queue and check for queue work */
+ spin_lock_irqsave(&dws->lock, flags);
+ if (list_empty(&dws->queue) || dws->run == QUEUE_STOPPED) {
+ dws->busy = 0;
+ spin_unlock_irqrestore(&dws->lock, flags);
+ return;
+ }
+
+ /* Make sure we are not already running a message */
+ if (dws->cur_msg) {
+ spin_unlock_irqrestore(&dws->lock, flags);
+ return;
+ }
+
+ /* Extract head of queue */
+ dws->cur_msg = list_entry(dws->queue.next, struct spi_message, queue);
+ list_del_init(&dws->cur_msg->queue);
+
+ /* Initial message state*/
+ dws->cur_msg->state = START_STATE;
+ dws->cur_transfer = list_entry(dws->cur_msg->transfers.next,
+ struct spi_transfer,
+ transfer_list);
+ dws->cur_chip = spi_get_ctldata(dws->cur_msg->spi);
+
+ /* Mark as busy and launch transfers */
+ tasklet_schedule(&dws->pump_transfers);
+
+ dws->busy = 1;
+ spin_unlock_irqrestore(&dws->lock, flags);
+}
+
+/* spi_device use this to queue in their spi_msg */
+static int dw_spi_transfer(struct spi_device *spi, struct spi_message *msg)
+{
+ struct dw_spi *dws = spi_master_get_devdata(spi->master);
+ unsigned long flags;
+
+ spin_lock_irqsave(&dws->lock, flags);
+
+ if (dws->run == QUEUE_STOPPED) {
+ spin_unlock_irqrestore(&dws->lock, flags);
+ return -ESHUTDOWN;
+ }
+
+ msg->actual_length = 0;
+ msg->status = -EINPROGRESS;
+ msg->state = START_STATE;
+
+ list_add_tail(&msg->queue, &dws->queue);
+
+ if (dws->run == QUEUE_RUNNING && !dws->busy) {
+
+ if (dws->cur_transfer || dws->cur_msg)
+ queue_work(dws->workqueue,
+ &dws->pump_messages);
+ else {
+ /* If no other data transaction in air, just go */
+ spin_unlock_irqrestore(&dws->lock, flags);
+ pump_messages(&dws->pump_messages);
+ return 0;
+ }
+ }
+
+ spin_unlock_irqrestore(&dws->lock, flags);
+ return 0;
+}
+
+/* This may be called twice for each spi dev */
+static int dw_spi_setup(struct spi_device *spi)
+{
+ struct dw_spi_chip *chip_info = NULL;
+ struct chip_data *chip;
+
+ if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
+ return -EINVAL;
+
+ /* Only alloc on first setup */
+ chip = spi_get_ctldata(spi);
+ if (!chip) {
+ chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
+ if (!chip)
+ return -ENOMEM;
+ }
+
+ /*
+ * Protocol drivers may change the chip settings, so...
+ * if chip_info exists, use it
+ */
+ chip_info = spi->controller_data;
+
+ /* chip_info doesn't always exist */
+ if (chip_info) {
+ if (chip_info->cs_control)
+ chip->cs_control = chip_info->cs_control;
+
+ chip->poll_mode = chip_info->poll_mode;
+ chip->type = chip_info->type;
+
+ chip->rx_threshold = 0;
+ chip->tx_threshold = 0;
+
+ chip->enable_dma = chip_info->enable_dma;
+ }
+
+ if (spi->bits_per_word <= 8) {
+ chip->n_bytes = 1;
+ chip->dma_width = 1;
+ } else if (spi->bits_per_word <= 16) {
+ chip->n_bytes = 2;
+ chip->dma_width = 2;
+ } else {
+ /* Never take >16b case for MRST SPIC */
+ dev_err(&spi->dev, "invalid wordsize\n");
+ return -EINVAL;
+ }
+ chip->bits_per_word = spi->bits_per_word;
+
+ if (!spi->max_speed_hz) {
+ dev_err(&spi->dev, "No max speed HZ parameter\n");
+ return -EINVAL;
+ }
+ chip->speed_hz = spi->max_speed_hz;
+
+ chip->tmode = 0; /* Tx & Rx */
+ /* Default SPI mode is SCPOL = 0, SCPH = 0 */
+ chip->cr0 = (chip->bits_per_word - 1)
+ | (chip->type << SPI_FRF_OFFSET)
+ | (spi->mode << SPI_MODE_OFFSET)
+ | (chip->tmode << SPI_TMOD_OFFSET);
+
+ spi_set_ctldata(spi, chip);
+ return 0;
+}
+
+static void dw_spi_cleanup(struct spi_device *spi)
+{
+ struct chip_data *chip = spi_get_ctldata(spi);
+ kfree(chip);
+}
+
+static int __devinit init_queue(struct dw_spi *dws)
+{
+ INIT_LIST_HEAD(&dws->queue);
+ spin_lock_init(&dws->lock);
+
+ dws->run = QUEUE_STOPPED;
+ dws->busy = 0;
+
+ tasklet_init(&dws->pump_transfers,
+ pump_transfers, (unsigned long)dws);
+
+ INIT_WORK(&dws->pump_messages, pump_messages);
+ dws->workqueue = create_singlethread_workqueue(
+ dev_name(dws->master->dev.parent));
+ if (dws->workqueue == NULL)
+ return -EBUSY;
+
+ return 0;
+}
+
+static int start_queue(struct dw_spi *dws)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&dws->lock, flags);
+
+ if (dws->run == QUEUE_RUNNING || dws->busy) {
+ spin_unlock_irqrestore(&dws->lock, flags);
+ return -EBUSY;
+ }
+
+ dws->run = QUEUE_RUNNING;
+ dws->cur_msg = NULL;
+ dws->cur_transfer = NULL;
+ dws->cur_chip = NULL;
+ dws->prev_chip = NULL;
+ spin_unlock_irqrestore(&dws->lock, flags);
+
+ queue_work(dws->workqueue, &dws->pump_messages);
+
+ return 0;
+}
+
+static int stop_queue(struct dw_spi *dws)
+{
+ unsigned long flags;
+ unsigned limit = 50;
+ int status = 0;
+
+ spin_lock_irqsave(&dws->lock, flags);
+ dws->run = QUEUE_STOPPED;
+ while ((!list_empty(&dws->queue) || dws->busy) && limit--) {
+ spin_unlock_irqrestore(&dws->lock, flags);
+ msleep(10);
+ spin_lock_irqsave(&dws->lock, flags);
+ }
+
+ if (!list_empty(&dws->queue) || dws->busy)
+ status = -EBUSY;
+ spin_unlock_irqrestore(&dws->lock, flags);
+
+ return status;
+}
+
+static int destroy_queue(struct dw_spi *dws)
+{
+ int status;
+
+ status = stop_queue(dws);
+ if (status != 0)
+ return status;
+ destroy_workqueue(dws->workqueue);
+ return 0;
+}
+
+/* Restart the controller, disable all interrupts, clean rx fifo */
+static void spi_hw_init(struct dw_spi *dws)
+{
+ spi_enable_chip(dws, 0);
+ spi_mask_intr(dws, 0xff);
+ spi_enable_chip(dws, 1);
+
+ /*
+ * Try to detect the FIFO depth if not set by interface driver,
+ * the depth could be from 2 to 256 from HW spec
+ */
+ if (!dws->fifo_len) {
+ u32 fifo;
+ for (fifo = 2; fifo <= 257; fifo++) {
+ dw_writew(dws, txfltr, fifo);
+ if (fifo != dw_readw(dws, txfltr))
+ break;
+ }
+
+ dws->fifo_len = (fifo == 257) ? 0 : fifo;
+ dw_writew(dws, txfltr, 0);
+ }
+}
+
+int __devinit dw_spi_add_host(struct dw_spi *dws)
+{
+ struct spi_master *master;
+ int ret;
+
+ BUG_ON(dws == NULL);
+
+ master = spi_alloc_master(dws->parent_dev, 0);
+ if (!master) {
+ ret = -ENOMEM;
+ goto exit;
+ }
+
+ dws->master = master;
+ dws->type = SSI_MOTO_SPI;
+ dws->prev_chip = NULL;
+ dws->dma_inited = 0;
+ dws->dma_addr = (dma_addr_t)(dws->paddr + 0x60);
+
+ ret = request_irq(dws->irq, dw_spi_irq, IRQF_SHARED,
+ "dw_spi", dws);
+ if (ret < 0) {
+ dev_err(&master->dev, "can not get IRQ\n");
+ goto err_free_master;
+ }
+
+ master->mode_bits = SPI_CPOL | SPI_CPHA;
+ master->bus_num = dws->bus_num;
+ master->num_chipselect = dws->num_cs;
+ master->cleanup = dw_spi_cleanup;
+ master->setup = dw_spi_setup;
+ master->transfer = dw_spi_transfer;
+
+ /* Basic HW init */
+ spi_hw_init(dws);
+
+ if (dws->dma_ops && dws->dma_ops->dma_init) {
+ ret = dws->dma_ops->dma_init(dws);
+ if (ret) {
+ dev_warn(&master->dev, "DMA init failed\n");
+ dws->dma_inited = 0;
+ }
+ }
+
+ /* Initial and start queue */
+ ret = init_queue(dws);
+ if (ret) {
+ dev_err(&master->dev, "problem initializing queue\n");
+ goto err_diable_hw;
+ }
+ ret = start_queue(dws);
+ if (ret) {
+ dev_err(&master->dev, "problem starting queue\n");
+ goto err_diable_hw;
+ }
+
+ spi_master_set_devdata(master, dws);
+ ret = spi_register_master(master);
+ if (ret) {
+ dev_err(&master->dev, "problem registering spi master\n");
+ goto err_queue_alloc;
+ }
+
+ mrst_spi_debugfs_init(dws);
+ return 0;
+
+err_queue_alloc:
+ destroy_queue(dws);
+ if (dws->dma_ops && dws->dma_ops->dma_exit)
+ dws->dma_ops->dma_exit(dws);
+err_diable_hw:
+ spi_enable_chip(dws, 0);
+ free_irq(dws->irq, dws);
+err_free_master:
+ spi_master_put(master);
+exit:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dw_spi_add_host);
+
+void __devexit dw_spi_remove_host(struct dw_spi *dws)
+{
+ int status = 0;
+
+ if (!dws)
+ return;
+ mrst_spi_debugfs_remove(dws);
+
+ /* Remove the queue */
+ status = destroy_queue(dws);
+ if (status != 0)
+ dev_err(&dws->master->dev, "dw_spi_remove: workqueue will not "
+ "complete, message memory not freed\n");
+
+ if (dws->dma_ops && dws->dma_ops->dma_exit)
+ dws->dma_ops->dma_exit(dws);
+ spi_enable_chip(dws, 0);
+ /* Disable clk */
+ spi_set_clk(dws, 0);
+ free_irq(dws->irq, dws);
+
+ /* Disconnect from the SPI framework */
+ spi_unregister_master(dws->master);
+}
+EXPORT_SYMBOL_GPL(dw_spi_remove_host);
+
+int dw_spi_suspend_host(struct dw_spi *dws)
+{
+ int ret = 0;
+
+ ret = stop_queue(dws);
+ if (ret)
+ return ret;
+ spi_enable_chip(dws, 0);
+ spi_set_clk(dws, 0);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dw_spi_suspend_host);
+
+int dw_spi_resume_host(struct dw_spi *dws)
+{
+ int ret;
+
+ spi_hw_init(dws);
+ ret = start_queue(dws);
+ if (ret)
+ dev_err(&dws->master->dev, "fail to start queue (%d)\n", ret);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dw_spi_resume_host);
+
+MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
+MODULE_DESCRIPTION("Driver for DesignWare SPI controller core");
+MODULE_LICENSE("GPL v2");