spi: controller driver for Designware SPI core
authorFeng Tang <feng.tang@intel.com>
Mon, 14 Dec 2009 22:20:22 +0000 (14:20 -0800)
committerGrant Likely <grant.likely@secretlab.ca>
Thu, 17 Dec 2009 15:39:13 +0000 (08:39 -0700)
Driver for the Designware SPI core, it supports multipul interfaces like
PCI/APB etc.  User can use "dw_apb_ssi_db.pdf" from Synopsys as HW
datasheet.

[randy.dunlap@oracle.com: fix build]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Feng Tang <feng.tang@intel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
drivers/spi/Kconfig
drivers/spi/Makefile
drivers/spi/dw_spi.c [new file with mode: 0644]
drivers/spi/dw_spi_pci.c [new file with mode: 0644]
include/linux/spi/dw_spi.h [new file with mode: 0644]

index 07e5453f7b18759fb030cc828e3c4a4309ab17ec..d7c1741c4c5b97139cd0e532585c6e2928d4ece4 100644 (file)
@@ -292,6 +292,16 @@ config SPI_NUC900
 # Add new SPI master controllers in alphabetical order above this line
 #
 
+config SPI_DESIGNWARE
+       bool "DesignWare SPI controller core support"
+       depends on SPI_MASTER
+       help
+         general driver for SPI controller core from DesignWare
+
+config SPI_DW_PCI
+       tristate "PCI interface driver for DW SPI core"
+       depends on SPI_DESIGNWARE && PCI
+
 #
 # There are lots of SPI device types, with sensors and memory
 # being probably the most widely used ones.
index ed8c1675b52f8c1af6918eb016fe871b85ccf973..a909e39f7e7c676e9fa975ad809fc0cd03b76957 100644 (file)
@@ -16,6 +16,8 @@ obj-$(CONFIG_SPI_BFIN)                        += spi_bfin5xx.o
 obj-$(CONFIG_SPI_BITBANG)              += spi_bitbang.o
 obj-$(CONFIG_SPI_AU1550)               += au1550_spi.o
 obj-$(CONFIG_SPI_BUTTERFLY)            += spi_butterfly.o
+obj-$(CONFIG_SPI_DESIGNWARE)           += dw_spi.o
+obj-$(CONFIG_SPI_DW_PCI)               += dw_spi_pci.o
 obj-$(CONFIG_SPI_GPIO)                 += spi_gpio.o
 obj-$(CONFIG_SPI_IMX)                  += spi_imx.o
 obj-$(CONFIG_SPI_LM70_LLP)             += spi_lm70llp.o
diff --git a/drivers/spi/dw_spi.c b/drivers/spi/dw_spi.c
new file mode 100644 (file)
index 0000000..31620fa
--- /dev/null
@@ -0,0 +1,944 @@
+/*
+ * dw_spi.c - 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/spi/dw_spi.h>
+#include <linux/spi/spi.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 */
+       int (*write)(struct dw_spi *dws);
+       int (*read)(struct dw_spi *dws);
+       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,
+};
+
+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)
+{
+}
+
+static inline void mrst_spi_debugfs_remove(struct dw_spi *dws)
+{
+}
+#endif /* CONFIG_DEBUG_FS */
+
+static void wait_till_not_busy(struct dw_spi *dws)
+{
+       unsigned long end = jiffies + usecs_to_jiffies(1000);
+
+       while (time_before(jiffies, end)) {
+               if (!(dw_readw(dws, sr) & SR_BUSY))
+                       return;
+       }
+       dev_err(&dws->master->dev,
+               "DW SPI: Stutus keeps busy for 1000us after a read/write!\n");
+}
+
+static void flush(struct dw_spi *dws)
+{
+       while (dw_readw(dws, sr) & SR_RF_NOT_EMPT)
+               dw_readw(dws, dr);
+
+       wait_till_not_busy(dws);
+}
+
+static void null_cs_control(u32 command)
+{
+}
+
+static int null_writer(struct dw_spi *dws)
+{
+       u8 n_bytes = dws->n_bytes;
+
+       if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
+               || (dws->tx == dws->tx_end))
+               return 0;
+       dw_writew(dws, dr, 0);
+       dws->tx += n_bytes;
+
+       wait_till_not_busy(dws);
+       return 1;
+}
+
+static int null_reader(struct dw_spi *dws)
+{
+       u8 n_bytes = dws->n_bytes;
+
+       while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
+               && (dws->rx < dws->rx_end)) {
+               dw_readw(dws, dr);
+               dws->rx += n_bytes;
+       }
+       wait_till_not_busy(dws);
+       return dws->rx == dws->rx_end;
+}
+
+static int u8_writer(struct dw_spi *dws)
+{
+       if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
+               || (dws->tx == dws->tx_end))
+               return 0;
+
+       dw_writew(dws, dr, *(u8 *)(dws->tx));
+       ++dws->tx;
+
+       wait_till_not_busy(dws);
+       return 1;
+}
+
+static int u8_reader(struct dw_spi *dws)
+{
+       while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
+               && (dws->rx < dws->rx_end)) {
+               *(u8 *)(dws->rx) = dw_readw(dws, dr);
+               ++dws->rx;
+       }
+
+       wait_till_not_busy(dws);
+       return dws->rx == dws->rx_end;
+}
+
+static int u16_writer(struct dw_spi *dws)
+{
+       if (!(dw_readw(dws, sr) & SR_TF_NOT_FULL)
+               || (dws->tx == dws->tx_end))
+               return 0;
+
+       dw_writew(dws, dr, *(u16 *)(dws->tx));
+       dws->tx += 2;
+
+       wait_till_not_busy(dws);
+       return 1;
+}
+
+static int u16_reader(struct dw_spi *dws)
+{
+       u16 temp;
+
+       while ((dw_readw(dws, sr) & SR_RF_NOT_EMPT)
+               && (dws->rx < dws->rx_end)) {
+               temp = dw_readw(dws, dr);
+               *(u16 *)(dws->rx) = temp;
+               dws->rx += 2;
+       }
+
+       wait_till_not_busy(dws);
+       return dws->rx == dws->rx_end;
+}
+
+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)
+               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(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 and reset hw */
+       flush(dws);
+       spi_enable_chip(dws, 0);
+
+       dev_err(&dws->master->dev, "%s\n", msg);
+       dws->cur_msg->state = ERROR_STATE;
+       tasklet_schedule(&dws->pump_transfers);
+}
+
+static void transfer_complete(struct dw_spi *dws)
+{
+       /* Update total byte transfered 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);
+}
+
+static irqreturn_t interrupt_transfer(struct dw_spi *dws)
+{
+       u16 irq_status, irq_mask = 0x3f;
+
+       irq_status = dw_readw(dws, isr) & irq_mask;
+       /* 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");
+               return IRQ_HANDLED;
+       }
+
+       /* INT comes from tx */
+       if (dws->tx && (irq_status & SPI_INT_TXEI)) {
+               while (dws->tx < dws->tx_end)
+                       dws->write(dws);
+
+               if (dws->tx == dws->tx_end) {
+                       spi_mask_intr(dws, SPI_INT_TXEI);
+                       transfer_complete(dws);
+               }
+       }
+
+       /* INT comes from rx */
+       if (dws->rx && (irq_status & SPI_INT_RXFI)) {
+               if (dws->read(dws))
+                       transfer_complete(dws);
+       }
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t dw_spi_irq(int irq, void *dev_id)
+{
+       struct dw_spi *dws = dev_id;
+
+       if (!dws->cur_msg) {
+               spi_mask_intr(dws, SPI_INT_TXEI);
+               /* Never fail */
+               return IRQ_HANDLED;
+       }
+
+       return dws->transfer_handler(dws);
+}
+
+/* Must be called inside pump_transfers() */
+static void poll_transfer(struct dw_spi *dws)
+{
+       if (dws->tx) {
+               while (dws->write(dws))
+                       dws->read(dws);
+       }
+
+       dws->read(dws);
+       transfer_complete(dws);
+}
+
+static void dma_transfer(struct dw_spi *dws, int cs_change)
+{
+}
+
+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 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 (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->write = dws->tx ? chip->write : null_writer;
+       dws->read = dws->rx ? chip->read : null_reader;
+       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) << 1;
+
+                       chip->speed_hz = speed;
+                       chip->clk_div = clk_div;
+               }
+       }
+       if (transfer->bits_per_word) {
+               bits = transfer->bits_per_word;
+
+               switch (bits) {
+               case 8:
+                       dws->n_bytes = 1;
+                       dws->dma_width = 1;
+                       dws->read = (dws->read != null_reader) ?
+                                       u8_reader : null_reader;
+                       dws->write = (dws->write != null_writer) ?
+                                       u8_writer : null_writer;
+                       break;
+               case 16:
+                       dws->n_bytes = 2;
+                       dws->dma_width = 2;
+                       dws->read = (dws->read != null_reader) ?
+                                       u16_reader : null_reader;
+                       dws->write = (dws->write != null_writer) ?
+                                       u16_writer : null_writer;
+                       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;
+
+       /* Check if current transfer is a DMA transaction */
+       dws->dma_mapped = map_dma_buffers(dws);
+
+       if (!dws->dma_mapped && !chip->poll_mode) {
+               if (dws->rx)
+                       imask |= SPI_INT_RXFI;
+               if (dws->tx)
+                       imask |= SPI_INT_TXEI;
+               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) {
+               spi_enable_chip(dws, 0);
+
+               if (dw_readw(dws, ctrl0) != cr0)
+                       dw_writew(dws, ctrl0, cr0);
+
+               /* Set the interrupt mask, for poll mode just diable all int */
+               spi_mask_intr(dws, 0xff);
+               if (!chip->poll_mode)
+                       spi_umask_intr(dws, imask);
+
+               spi_set_clk(dws, clk_div ? clk_div : chip->clk_div);
+               spi_chip_sel(dws, spi->chip_select);
+               spi_enable_chip(dws, 1);
+
+               if (cs_change)
+                       dws->prev_chip = chip;
+       }
+
+       if (dws->dma_mapped)
+               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;
+
+               chip->cs_control = null_cs_control;
+               chip->enable_dma = 0;
+       }
+
+       /*
+        * 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;
+               chip->read = u8_reader;
+               chip->write = u8_writer;
+       } else if (spi->bits_per_word <= 16) {
+               chip->n_bytes = 2;
+               chip->dma_width = 2;
+               chip->read = u16_reader;
+               chip->write = u16_writer;
+       } 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;
+
+       chip->speed_hz = spi->max_speed_hz;
+       if (chip->speed_hz)
+               chip->clk_div = 25000000 / chip->speed_hz;
+       else
+               chip->clk_div = 8;      /* default value */
+
+       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 __init 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);
+       flush(dws);
+}
+
+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, 0,
+                       "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;
+
+       dws->dma_inited = 0;
+
+       /* Basic HW init */
+       spi_hw_init(dws);
+
+       /* 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);
+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(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");
+
+       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);
+}
+
+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(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(dw_spi_resume_host);
+
+MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
+MODULE_DESCRIPTION("Driver for DesignWare SPI controller core");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/spi/dw_spi_pci.c b/drivers/spi/dw_spi_pci.c
new file mode 100644 (file)
index 0000000..34ba691
--- /dev/null
@@ -0,0 +1,169 @@
+/*
+ * mrst_spi_pci.c - PCI interface driver for DW SPI Core
+ *
+ * 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/interrupt.h>
+#include <linux/pci.h>
+#include <linux/spi/dw_spi.h>
+#include <linux/spi/spi.h>
+
+#define DRIVER_NAME "dw_spi_pci"
+
+struct dw_spi_pci {
+       struct pci_dev          *pdev;
+       struct dw_spi           dws;
+};
+
+static int __devinit spi_pci_probe(struct pci_dev *pdev,
+       const struct pci_device_id *ent)
+{
+       struct dw_spi_pci *dwpci;
+       struct dw_spi *dws;
+       int pci_bar = 0;
+       int ret;
+
+       printk(KERN_INFO "DW: found PCI SPI controller(ID: %04x:%04x)\n",
+               pdev->vendor, pdev->device);
+
+       ret = pci_enable_device(pdev);
+       if (ret)
+               return ret;
+
+       dwpci = kzalloc(sizeof(struct dw_spi_pci), GFP_KERNEL);
+       if (!dwpci) {
+               ret = -ENOMEM;
+               goto err_disable;
+       }
+
+       dwpci->pdev = pdev;
+       dws = &dwpci->dws;
+
+       /* Get basic io resource and map it */
+       dws->paddr = pci_resource_start(pdev, pci_bar);
+       dws->iolen = pci_resource_len(pdev, pci_bar);
+
+       ret = pci_request_region(pdev, pci_bar, dev_name(&pdev->dev));
+       if (ret)
+               goto err_kfree;
+
+       dws->regs = ioremap_nocache((unsigned long)dws->paddr,
+                               pci_resource_len(pdev, pci_bar));
+       if (!dws->regs) {
+               ret = -ENOMEM;
+               goto err_release_reg;
+       }
+
+       dws->parent_dev = &pdev->dev;
+       dws->bus_num = 0;
+       dws->num_cs = 4;
+       dws->max_freq = 25000000;       /* for Moorestwon */
+       dws->irq = pdev->irq;
+
+       ret = dw_spi_add_host(dws);
+       if (ret)
+               goto err_unmap;
+
+       /* PCI hook and SPI hook use the same drv data */
+       pci_set_drvdata(pdev, dwpci);
+       return 0;
+
+err_unmap:
+       iounmap(dws->regs);
+err_release_reg:
+       pci_release_region(pdev, pci_bar);
+err_kfree:
+       kfree(dwpci);
+err_disable:
+       pci_disable_device(pdev);
+       return ret;
+}
+
+static void __devexit spi_pci_remove(struct pci_dev *pdev)
+{
+       struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
+
+       pci_set_drvdata(pdev, NULL);
+       iounmap(dwpci->dws.regs);
+       pci_release_region(pdev, 0);
+       kfree(dwpci);
+       pci_disable_device(pdev);
+}
+
+#ifdef CONFIG_PM
+static int spi_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+       struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
+       int ret;
+
+       ret = dw_spi_suspend_host(&dwpci->dws);
+       if (ret)
+               return ret;
+       pci_save_state(pdev);
+       pci_disable_device(pdev);
+       pci_set_power_state(pdev, pci_choose_state(pdev, state));
+       return ret;
+}
+
+static int spi_resume(struct pci_dev *pdev)
+{
+       struct dw_spi_pci *dwpci = pci_get_drvdata(pdev);
+       int ret;
+
+       pci_set_power_state(pdev, PCI_D0);
+       pci_restore_state(pdev);
+       ret = pci_enable_device(pdev);
+       if (ret)
+               return ret;
+       return dw_spi_resume_host(&dwpci->dws);
+}
+#else
+#define spi_suspend    NULL
+#define spi_resume     NULL
+#endif
+
+static const struct pci_device_id pci_ids[] __devinitdata = {
+       /* Intel Moorestown platform SPI controller 0 */
+       { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x0800) },
+       {},
+};
+
+static struct pci_driver dw_spi_driver = {
+       .name =         DRIVER_NAME,
+       .id_table =     pci_ids,
+       .probe =        spi_pci_probe,
+       .remove =       __devexit_p(spi_pci_remove),
+       .suspend =      spi_suspend,
+       .resume =       spi_resume,
+};
+
+static int __init mrst_spi_init(void)
+{
+       return pci_register_driver(&dw_spi_driver);
+}
+
+static void __exit mrst_spi_exit(void)
+{
+       pci_unregister_driver(&dw_spi_driver);
+}
+
+module_init(mrst_spi_init);
+module_exit(mrst_spi_exit);
+
+MODULE_AUTHOR("Feng Tang <feng.tang@intel.com>");
+MODULE_DESCRIPTION("PCI interface driver for DW SPI Core");
+MODULE_LICENSE("GPL v2");
diff --git a/include/linux/spi/dw_spi.h b/include/linux/spi/dw_spi.h
new file mode 100644 (file)
index 0000000..51b3e77
--- /dev/null
@@ -0,0 +1,212 @@
+#ifndef DW_SPI_HEADER_H
+#define DW_SPI_HEADER_H
+#include <linux/io.h>
+
+/* Bit fields in CTRLR0 */
+#define SPI_DFS_OFFSET                 0
+
+#define SPI_FRF_OFFSET                 4
+#define SPI_FRF_SPI                    0x0
+#define SPI_FRF_SSP                    0x1
+#define SPI_FRF_MICROWIRE              0x2
+#define SPI_FRF_RESV                   0x3
+
+#define SPI_MODE_OFFSET                        6
+#define SPI_SCPH_OFFSET                        6
+#define SPI_SCOL_OFFSET                        7
+#define SPI_TMOD_OFFSET                        8
+#define        SPI_TMOD_TR                     0x0             /* xmit & recv */
+#define SPI_TMOD_TO                    0x1             /* xmit only */
+#define SPI_TMOD_RO                    0x2             /* recv only */
+#define SPI_TMOD_EPROMREAD             0x3             /* eeprom read mode */
+
+#define SPI_SLVOE_OFFSET               10
+#define SPI_SRL_OFFSET                 11
+#define SPI_CFS_OFFSET                 12
+
+/* Bit fields in SR, 7 bits */
+#define SR_MASK                                0x7f            /* cover 7 bits */
+#define SR_BUSY                                (1 << 0)
+#define SR_TF_NOT_FULL                 (1 << 1)
+#define SR_TF_EMPT                     (1 << 2)
+#define SR_RF_NOT_EMPT                 (1 << 3)
+#define SR_RF_FULL                     (1 << 4)
+#define SR_TX_ERR                      (1 << 5)
+#define SR_DCOL                                (1 << 6)
+
+/* Bit fields in ISR, IMR, RISR, 7 bits */
+#define SPI_INT_TXEI                   (1 << 0)
+#define SPI_INT_TXOI                   (1 << 1)
+#define SPI_INT_RXUI                   (1 << 2)
+#define SPI_INT_RXOI                   (1 << 3)
+#define SPI_INT_RXFI                   (1 << 4)
+#define SPI_INT_MSTI                   (1 << 5)
+
+/* TX RX interrupt level threshhold, max can be 256 */
+#define SPI_INT_THRESHOLD              32
+
+enum dw_ssi_type {
+       SSI_MOTO_SPI = 0,
+       SSI_TI_SSP,
+       SSI_NS_MICROWIRE,
+};
+
+struct dw_spi_reg {
+       u32     ctrl0;
+       u32     ctrl1;
+       u32     ssienr;
+       u32     mwcr;
+       u32     ser;
+       u32     baudr;
+       u32     txfltr;
+       u32     rxfltr;
+       u32     txflr;
+       u32     rxflr;
+       u32     sr;
+       u32     imr;
+       u32     isr;
+       u32     risr;
+       u32     txoicr;
+       u32     rxoicr;
+       u32     rxuicr;
+       u32     msticr;
+       u32     icr;
+       u32     dmacr;
+       u32     dmatdlr;
+       u32     dmardlr;
+       u32     idr;
+       u32     version;
+       u32     dr;             /* Currently oper as 32 bits,
+                               though only low 16 bits matters */
+} __packed;
+
+struct dw_spi {
+       struct spi_master       *master;
+       struct spi_device       *cur_dev;
+       struct device           *parent_dev;
+       enum dw_ssi_type        type;
+
+       void __iomem            *regs;
+       unsigned long           paddr;
+       u32                     iolen;
+       int                     irq;
+       u32                     max_freq;       /* max bus freq supported */
+
+       u16                     bus_num;
+       u16                     num_cs;         /* supported slave numbers */
+
+       /* Driver message queue */
+       struct workqueue_struct *workqueue;
+       struct work_struct      pump_messages;
+       spinlock_t              lock;
+       struct list_head        queue;
+       int                     busy;
+       int                     run;
+
+       /* Message Transfer pump */
+       struct tasklet_struct   pump_transfers;
+
+       /* Current message transfer state info */
+       struct spi_message      *cur_msg;
+       struct spi_transfer     *cur_transfer;
+       struct chip_data        *cur_chip;
+       struct chip_data        *prev_chip;
+       size_t                  len;
+       void                    *tx;
+       void                    *tx_end;
+       void                    *rx;
+       void                    *rx_end;
+       int                     dma_mapped;
+       dma_addr_t              rx_dma;
+       dma_addr_t              tx_dma;
+       size_t                  rx_map_len;
+       size_t                  tx_map_len;
+       u8                      n_bytes;        /* current is a 1/2 bytes op */
+       u8                      max_bits_per_word;      /* maxim is 16b */
+       u32                     dma_width;
+       int                     cs_change;
+       int                     (*write)(struct dw_spi *dws);
+       int                     (*read)(struct dw_spi *dws);
+       irqreturn_t             (*transfer_handler)(struct dw_spi *dws);
+       void                    (*cs_control)(u32 command);
+
+       /* Dma info */
+       int                     dma_inited;
+       struct dma_chan         *txchan;
+       struct dma_chan         *rxchan;
+       int                     txdma_done;
+       int                     rxdma_done;
+       u64                     tx_param;
+       u64                     rx_param;
+       struct device           *dma_dev;
+       dma_addr_t              dma_addr;
+
+       /* Bus interface info */
+       void                    *priv;
+#ifdef CONFIG_DEBUG_FS
+       struct dentry *debugfs;
+#endif
+};
+
+#define dw_readl(dw, name) \
+       __raw_readl(&(((struct dw_spi_reg *)dw->regs)->name))
+#define dw_writel(dw, name, val) \
+       __raw_writel((val), &(((struct dw_spi_reg *)dw->regs)->name))
+#define dw_readw(dw, name) \
+       __raw_readw(&(((struct dw_spi_reg *)dw->regs)->name))
+#define dw_writew(dw, name, val) \
+       __raw_writew((val), &(((struct dw_spi_reg *)dw->regs)->name))
+
+static inline void spi_enable_chip(struct dw_spi *dws, int enable)
+{
+       dw_writel(dws, ssienr, (enable ? 1 : 0));
+}
+
+static inline void spi_set_clk(struct dw_spi *dws, u16 div)
+{
+       dw_writel(dws, baudr, div);
+}
+
+static inline void spi_chip_sel(struct dw_spi *dws, u16 cs)
+{
+       if (cs > dws->num_cs)
+               return;
+       dw_writel(dws, ser, 1 << cs);
+}
+
+/* Disable IRQ bits */
+static inline void spi_mask_intr(struct dw_spi *dws, u32 mask)
+{
+       u32 new_mask;
+
+       new_mask = dw_readl(dws, imr) & ~mask;
+       dw_writel(dws, imr, new_mask);
+}
+
+/* Enable IRQ bits */
+static inline void spi_umask_intr(struct dw_spi *dws, u32 mask)
+{
+       u32 new_mask;
+
+       new_mask = dw_readl(dws, imr) | mask;
+       dw_writel(dws, imr, new_mask);
+}
+
+/*
+ * Each SPI slave device to work with dw_api controller should
+ * has such a structure claiming its working mode (PIO/DMA etc),
+ * which can be save in the "controller_data" member of the
+ * struct spi_device
+ */
+struct dw_spi_chip {
+       u8 poll_mode;   /* 0 for contoller polling mode */
+       u8 type;        /* SPI/SSP/Micrwire */
+       u8 enable_dma;
+       void (*cs_control)(u32 command);
+};
+
+extern int dw_spi_add_host(struct dw_spi *dws);
+extern void dw_spi_remove_host(struct dw_spi *dws);
+extern int dw_spi_suspend_host(struct dw_spi *dws);
+extern int dw_spi_resume_host(struct dw_spi *dws);
+#endif /* DW_SPI_HEADER_H */