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path: root/drivers/spi/spi-topcliff-pch.c
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-rw-r--r--drivers/spi/spi-topcliff-pch.c1303
1 files changed, 1303 insertions, 0 deletions
diff --git a/drivers/spi/spi-topcliff-pch.c b/drivers/spi/spi-topcliff-pch.c
new file mode 100644
index 00000000000..79e48d45113
--- /dev/null
+++ b/drivers/spi/spi-topcliff-pch.c
@@ -0,0 +1,1303 @@
+/*
+ * SPI bus driver for the Topcliff PCH used by Intel SoCs
+ *
+ * Copyright (C) 2010 OKI SEMICONDUCTOR Co., LTD.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <linux/delay.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+#include <linux/spi/spi.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/spi/spidev.h>
+#include <linux/module.h>
+#include <linux/device.h>
+
+/* Register offsets */
+#define PCH_SPCR 0x00 /* SPI control register */
+#define PCH_SPBRR 0x04 /* SPI baud rate register */
+#define PCH_SPSR 0x08 /* SPI status register */
+#define PCH_SPDWR 0x0C /* SPI write data register */
+#define PCH_SPDRR 0x10 /* SPI read data register */
+#define PCH_SSNXCR 0x18 /* SSN Expand Control Register */
+#define PCH_SRST 0x1C /* SPI reset register */
+
+#define PCH_SPSR_TFD 0x000007C0
+#define PCH_SPSR_RFD 0x0000F800
+
+#define PCH_READABLE(x) (((x) & PCH_SPSR_RFD)>>11)
+#define PCH_WRITABLE(x) (((x) & PCH_SPSR_TFD)>>6)
+
+#define PCH_RX_THOLD 7
+#define PCH_RX_THOLD_MAX 15
+
+#define PCH_MAX_BAUDRATE 5000000
+#define PCH_MAX_FIFO_DEPTH 16
+
+#define STATUS_RUNNING 1
+#define STATUS_EXITING 2
+#define PCH_SLEEP_TIME 10
+
+#define PCH_ADDRESS_SIZE 0x20
+
+#define SSN_LOW 0x02U
+#define SSN_NO_CONTROL 0x00U
+#define PCH_MAX_CS 0xFF
+#define PCI_DEVICE_ID_GE_SPI 0x8816
+
+#define SPCR_SPE_BIT (1 << 0)
+#define SPCR_MSTR_BIT (1 << 1)
+#define SPCR_LSBF_BIT (1 << 4)
+#define SPCR_CPHA_BIT (1 << 5)
+#define SPCR_CPOL_BIT (1 << 6)
+#define SPCR_TFIE_BIT (1 << 8)
+#define SPCR_RFIE_BIT (1 << 9)
+#define SPCR_FIE_BIT (1 << 10)
+#define SPCR_ORIE_BIT (1 << 11)
+#define SPCR_MDFIE_BIT (1 << 12)
+#define SPCR_FICLR_BIT (1 << 24)
+#define SPSR_TFI_BIT (1 << 0)
+#define SPSR_RFI_BIT (1 << 1)
+#define SPSR_FI_BIT (1 << 2)
+#define SPBRR_SIZE_BIT (1 << 10)
+
+#define PCH_ALL (SPCR_TFIE_BIT|SPCR_RFIE_BIT|SPCR_FIE_BIT|SPCR_ORIE_BIT|SPCR_MDFIE_BIT)
+
+#define SPCR_RFIC_FIELD 20
+#define SPCR_TFIC_FIELD 16
+
+#define SPSR_INT_BITS 0x1F
+#define MASK_SPBRR_SPBR_BITS (~((1 << 10) - 1))
+#define MASK_RFIC_SPCR_BITS (~(0xf << 20))
+#define MASK_TFIC_SPCR_BITS (~(0xf000f << 12))
+
+#define PCH_CLOCK_HZ 50000000
+#define PCH_MAX_SPBR 1023
+
+
+/**
+ * struct pch_spi_data - Holds the SPI channel specific details
+ * @io_remap_addr: The remapped PCI base address
+ * @master: Pointer to the SPI master structure
+ * @work: Reference to work queue handler
+ * @wk: Workqueue for carrying out execution of the
+ * requests
+ * @wait: Wait queue for waking up upon receiving an
+ * interrupt.
+ * @transfer_complete: Status of SPI Transfer
+ * @bcurrent_msg_processing: Status flag for message processing
+ * @lock: Lock for protecting this structure
+ * @queue: SPI Message queue
+ * @status: Status of the SPI driver
+ * @bpw_len: Length of data to be transferred in bits per
+ * word
+ * @transfer_active: Flag showing active transfer
+ * @tx_index: Transmit data count; for bookkeeping during
+ * transfer
+ * @rx_index: Receive data count; for bookkeeping during
+ * transfer
+ * @tx_buff: Buffer for data to be transmitted
+ * @rx_index: Buffer for Received data
+ * @n_curnt_chip: The chip number that this SPI driver currently
+ * operates on
+ * @current_chip: Reference to the current chip that this SPI
+ * driver currently operates on
+ * @current_msg: The current message that this SPI driver is
+ * handling
+ * @cur_trans: The current transfer that this SPI driver is
+ * handling
+ * @board_dat: Reference to the SPI device data structure
+ */
+struct pch_spi_data {
+ void __iomem *io_remap_addr;
+ struct spi_master *master;
+ struct work_struct work;
+ struct workqueue_struct *wk;
+ wait_queue_head_t wait;
+ u8 transfer_complete;
+ u8 bcurrent_msg_processing;
+ spinlock_t lock;
+ struct list_head queue;
+ u8 status;
+ u32 bpw_len;
+ u8 transfer_active;
+ u32 tx_index;
+ u32 rx_index;
+ u16 *pkt_tx_buff;
+ u16 *pkt_rx_buff;
+ u8 n_curnt_chip;
+ struct spi_device *current_chip;
+ struct spi_message *current_msg;
+ struct spi_transfer *cur_trans;
+ struct pch_spi_board_data *board_dat;
+};
+
+/**
+ * struct pch_spi_board_data - Holds the SPI device specific details
+ * @pdev: Pointer to the PCI device
+ * @irq_reg_sts: Status of IRQ registration
+ * @pci_req_sts: Status of pci_request_regions
+ * @suspend_sts: Status of suspend
+ * @data: Pointer to SPI channel data structure
+ */
+struct pch_spi_board_data {
+ struct pci_dev *pdev;
+ u8 irq_reg_sts;
+ u8 pci_req_sts;
+ u8 suspend_sts;
+ struct pch_spi_data *data;
+};
+
+static struct pci_device_id pch_spi_pcidev_id[] = {
+ {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_GE_SPI)},
+ {0,}
+};
+
+/**
+ * pch_spi_writereg() - Performs register writes
+ * @master: Pointer to struct spi_master.
+ * @idx: Register offset.
+ * @val: Value to be written to register.
+ */
+static inline void pch_spi_writereg(struct spi_master *master, int idx, u32 val)
+{
+ struct pch_spi_data *data = spi_master_get_devdata(master);
+ iowrite32(val, (data->io_remap_addr + idx));
+}
+
+/**
+ * pch_spi_readreg() - Performs register reads
+ * @master: Pointer to struct spi_master.
+ * @idx: Register offset.
+ */
+static inline u32 pch_spi_readreg(struct spi_master *master, int idx)
+{
+ struct pch_spi_data *data = spi_master_get_devdata(master);
+ return ioread32(data->io_remap_addr + idx);
+}
+
+static inline void pch_spi_setclr_reg(struct spi_master *master, int idx,
+ u32 set, u32 clr)
+{
+ u32 tmp = pch_spi_readreg(master, idx);
+ tmp = (tmp & ~clr) | set;
+ pch_spi_writereg(master, idx, tmp);
+}
+
+static void pch_spi_set_master_mode(struct spi_master *master)
+{
+ pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MSTR_BIT, 0);
+}
+
+/**
+ * pch_spi_clear_fifo() - Clears the Transmit and Receive FIFOs
+ * @master: Pointer to struct spi_master.
+ */
+static void pch_spi_clear_fifo(struct spi_master *master)
+{
+ pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FICLR_BIT, 0);
+ pch_spi_setclr_reg(master, PCH_SPCR, 0, SPCR_FICLR_BIT);
+}
+
+static void pch_spi_handler_sub(struct pch_spi_data *data, u32 reg_spsr_val,
+ void __iomem *io_remap_addr)
+{
+ u32 n_read, tx_index, rx_index, bpw_len;
+ u16 *pkt_rx_buffer, *pkt_tx_buff;
+ int read_cnt;
+ u32 reg_spcr_val;
+ void __iomem *spsr;
+ void __iomem *spdrr;
+ void __iomem *spdwr;
+
+ spsr = io_remap_addr + PCH_SPSR;
+ iowrite32(reg_spsr_val, spsr);
+
+ if (data->transfer_active) {
+ rx_index = data->rx_index;
+ tx_index = data->tx_index;
+ bpw_len = data->bpw_len;
+ pkt_rx_buffer = data->pkt_rx_buff;
+ pkt_tx_buff = data->pkt_tx_buff;
+
+ spdrr = io_remap_addr + PCH_SPDRR;
+ spdwr = io_remap_addr + PCH_SPDWR;
+
+ n_read = PCH_READABLE(reg_spsr_val);
+
+ for (read_cnt = 0; (read_cnt < n_read); read_cnt++) {
+ pkt_rx_buffer[rx_index++] = ioread32(spdrr);
+ if (tx_index < bpw_len)
+ iowrite32(pkt_tx_buff[tx_index++], spdwr);
+ }
+
+ /* disable RFI if not needed */
+ if ((bpw_len - rx_index) <= PCH_MAX_FIFO_DEPTH) {
+ reg_spcr_val = ioread32(io_remap_addr + PCH_SPCR);
+ reg_spcr_val &= ~SPCR_RFIE_BIT; /* disable RFI */
+
+ /* reset rx threshold */
+ reg_spcr_val &= MASK_RFIC_SPCR_BITS;
+ reg_spcr_val |= (PCH_RX_THOLD_MAX << SPCR_RFIC_FIELD);
+ iowrite32(((reg_spcr_val) &= (~(SPCR_RFIE_BIT))),
+ (io_remap_addr + PCH_SPCR));
+ }
+
+ /* update counts */
+ data->tx_index = tx_index;
+ data->rx_index = rx_index;
+
+ }
+
+ /* if transfer complete interrupt */
+ if (reg_spsr_val & SPSR_FI_BIT) {
+ /* disable FI & RFI interrupts */
+ pch_spi_setclr_reg(data->master, PCH_SPCR, 0,
+ SPCR_FIE_BIT | SPCR_RFIE_BIT);
+
+ /* transfer is completed;inform pch_spi_process_messages */
+ data->transfer_complete = true;
+ wake_up(&data->wait);
+ }
+}
+
+/**
+ * pch_spi_handler() - Interrupt handler
+ * @irq: The interrupt number.
+ * @dev_id: Pointer to struct pch_spi_board_data.
+ */
+static irqreturn_t pch_spi_handler(int irq, void *dev_id)
+{
+ u32 reg_spsr_val;
+ struct pch_spi_data *data;
+ void __iomem *spsr;
+ void __iomem *io_remap_addr;
+ irqreturn_t ret = IRQ_NONE;
+ struct pch_spi_board_data *board_dat = dev_id;
+
+ if (board_dat->suspend_sts) {
+ dev_dbg(&board_dat->pdev->dev,
+ "%s returning due to suspend\n", __func__);
+ return IRQ_NONE;
+ }
+
+ data = board_dat->data;
+ io_remap_addr = data->io_remap_addr;
+ spsr = io_remap_addr + PCH_SPSR;
+
+ reg_spsr_val = ioread32(spsr);
+
+ /* Check if the interrupt is for SPI device */
+ if (reg_spsr_val & (SPSR_FI_BIT | SPSR_RFI_BIT)) {
+ pch_spi_handler_sub(data, reg_spsr_val, io_remap_addr);
+ ret = IRQ_HANDLED;
+ }
+
+ dev_dbg(&board_dat->pdev->dev, "%s EXIT return value=%d\n",
+ __func__, ret);
+
+ return ret;
+}
+
+/**
+ * pch_spi_set_baud_rate() - Sets SPBR field in SPBRR
+ * @master: Pointer to struct spi_master.
+ * @speed_hz: Baud rate.
+ */
+static void pch_spi_set_baud_rate(struct spi_master *master, u32 speed_hz)
+{
+ u32 n_spbr = PCH_CLOCK_HZ / (speed_hz * 2);
+
+ /* if baud rate is less than we can support limit it */
+ if (n_spbr > PCH_MAX_SPBR)
+ n_spbr = PCH_MAX_SPBR;
+
+ pch_spi_setclr_reg(master, PCH_SPBRR, n_spbr, ~MASK_SPBRR_SPBR_BITS);
+}
+
+/**
+ * pch_spi_set_bits_per_word() - Sets SIZE field in SPBRR
+ * @master: Pointer to struct spi_master.
+ * @bits_per_word: Bits per word for SPI transfer.
+ */
+static void pch_spi_set_bits_per_word(struct spi_master *master,
+ u8 bits_per_word)
+{
+ if (bits_per_word == 8)
+ pch_spi_setclr_reg(master, PCH_SPBRR, 0, SPBRR_SIZE_BIT);
+ else
+ pch_spi_setclr_reg(master, PCH_SPBRR, SPBRR_SIZE_BIT, 0);
+}
+
+/**
+ * pch_spi_setup_transfer() - Configures the PCH SPI hardware for transfer
+ * @spi: Pointer to struct spi_device.
+ */
+static void pch_spi_setup_transfer(struct spi_device *spi)
+{
+ u32 flags = 0;
+
+ dev_dbg(&spi->dev, "%s SPBRR content =%x setting baud rate=%d\n",
+ __func__, pch_spi_readreg(spi->master, PCH_SPBRR),
+ spi->max_speed_hz);
+ pch_spi_set_baud_rate(spi->master, spi->max_speed_hz);
+
+ /* set bits per word */
+ pch_spi_set_bits_per_word(spi->master, spi->bits_per_word);
+
+ if (!(spi->mode & SPI_LSB_FIRST))
+ flags |= SPCR_LSBF_BIT;
+ if (spi->mode & SPI_CPOL)
+ flags |= SPCR_CPOL_BIT;
+ if (spi->mode & SPI_CPHA)
+ flags |= SPCR_CPHA_BIT;
+ pch_spi_setclr_reg(spi->master, PCH_SPCR, flags,
+ (SPCR_LSBF_BIT | SPCR_CPOL_BIT | SPCR_CPHA_BIT));
+
+ /* Clear the FIFO by toggling FICLR to 1 and back to 0 */
+ pch_spi_clear_fifo(spi->master);
+}
+
+/**
+ * pch_spi_reset() - Clears SPI registers
+ * @master: Pointer to struct spi_master.
+ */
+static void pch_spi_reset(struct spi_master *master)
+{
+ /* write 1 to reset SPI */
+ pch_spi_writereg(master, PCH_SRST, 0x1);
+
+ /* clear reset */
+ pch_spi_writereg(master, PCH_SRST, 0x0);
+}
+
+static int pch_spi_setup(struct spi_device *pspi)
+{
+ /* check bits per word */
+ if (pspi->bits_per_word == 0) {
+ pspi->bits_per_word = 8;
+ dev_dbg(&pspi->dev, "%s 8 bits per word\n", __func__);
+ }
+
+ if ((pspi->bits_per_word != 8) && (pspi->bits_per_word != 16)) {
+ dev_err(&pspi->dev, "%s Invalid bits per word\n", __func__);
+ return -EINVAL;
+ }
+
+ /* Check baud rate setting */
+ /* if baud rate of chip is greater than
+ max we can support,return error */
+ if ((pspi->max_speed_hz) > PCH_MAX_BAUDRATE)
+ pspi->max_speed_hz = PCH_MAX_BAUDRATE;
+
+ dev_dbg(&pspi->dev, "%s MODE = %x\n", __func__,
+ (pspi->mode) & (SPI_CPOL | SPI_CPHA));
+
+ return 0;
+}
+
+static int pch_spi_transfer(struct spi_device *pspi, struct spi_message *pmsg)
+{
+
+ struct spi_transfer *transfer;
+ struct pch_spi_data *data = spi_master_get_devdata(pspi->master);
+ int retval;
+ unsigned long flags;
+
+ /* validate spi message and baud rate */
+ if (unlikely(list_empty(&pmsg->transfers) == 1)) {
+ dev_err(&pspi->dev, "%s list empty\n", __func__);
+ retval = -EINVAL;
+ goto err_out;
+ }
+
+ if (unlikely(pspi->max_speed_hz == 0)) {
+ dev_err(&pspi->dev, "%s pch_spi_tranfer maxspeed=%d\n",
+ __func__, pspi->max_speed_hz);
+ retval = -EINVAL;
+ goto err_out;
+ }
+
+ dev_dbg(&pspi->dev, "%s Transfer List not empty. "
+ "Transfer Speed is set.\n", __func__);
+
+ /* validate Tx/Rx buffers and Transfer length */
+ list_for_each_entry(transfer, &pmsg->transfers, transfer_list) {
+ if (!transfer->tx_buf && !transfer->rx_buf) {
+ dev_err(&pspi->dev,
+ "%s Tx and Rx buffer NULL\n", __func__);
+ retval = -EINVAL;
+ goto err_out;
+ }
+
+ if (!transfer->len) {
+ dev_err(&pspi->dev, "%s Transfer length invalid\n",
+ __func__);
+ retval = -EINVAL;
+ goto err_out;
+ }
+
+ dev_dbg(&pspi->dev, "%s Tx/Rx buffer valid. Transfer length"
+ " valid\n", __func__);
+
+ /* if baud rate hs been specified validate the same */
+ if (transfer->speed_hz > PCH_MAX_BAUDRATE)
+ transfer->speed_hz = PCH_MAX_BAUDRATE;
+
+ /* if bits per word has been specified validate the same */
+ if (transfer->bits_per_word) {
+ if ((transfer->bits_per_word != 8)
+ && (transfer->bits_per_word != 16)) {
+ retval = -EINVAL;
+ dev_err(&pspi->dev,
+ "%s Invalid bits per word\n", __func__);
+ goto err_out;
+ }
+ }
+ }
+
+ spin_lock_irqsave(&data->lock, flags);
+
+ /* We won't process any messages if we have been asked to terminate */
+ if (data->status == STATUS_EXITING) {
+ dev_err(&pspi->dev, "%s status = STATUS_EXITING.\n", __func__);
+ retval = -ESHUTDOWN;
+ goto err_return_spinlock;
+ }
+
+ /* If suspended ,return -EINVAL */
+ if (data->board_dat->suspend_sts) {
+ dev_err(&pspi->dev, "%s suspend; returning EINVAL\n", __func__);
+ retval = -EINVAL;
+ goto err_return_spinlock;
+ }
+
+ /* set status of message */
+ pmsg->actual_length = 0;
+ dev_dbg(&pspi->dev, "%s - pmsg->status =%d\n", __func__, pmsg->status);
+
+ pmsg->status = -EINPROGRESS;
+
+ /* add message to queue */
+ list_add_tail(&pmsg->queue, &data->queue);
+ dev_dbg(&pspi->dev, "%s - Invoked list_add_tail\n", __func__);
+
+ /* schedule work queue to run */
+ queue_work(data->wk, &data->work);
+ dev_dbg(&pspi->dev, "%s - Invoked queue work\n", __func__);
+
+ retval = 0;
+
+err_return_spinlock:
+ spin_unlock_irqrestore(&data->lock, flags);
+err_out:
+ dev_dbg(&pspi->dev, "%s RETURN=%d\n", __func__, retval);
+ return retval;
+}
+
+static inline void pch_spi_select_chip(struct pch_spi_data *data,
+ struct spi_device *pspi)
+{
+ if (data->current_chip != NULL) {
+ if (pspi->chip_select != data->n_curnt_chip) {
+ dev_dbg(&pspi->dev, "%s : different slave\n", __func__);
+ data->current_chip = NULL;
+ }
+ }
+
+ data->current_chip = pspi;
+
+ data->n_curnt_chip = data->current_chip->chip_select;
+
+ dev_dbg(&pspi->dev, "%s :Invoking pch_spi_setup_transfer\n", __func__);
+ pch_spi_setup_transfer(pspi);
+}
+
+static void pch_spi_set_tx(struct pch_spi_data *data, int *bpw,
+ struct spi_message **ppmsg)
+{
+ int size;
+ u32 n_writes;
+ int j;
+ struct spi_message *pmsg;
+ const u8 *tx_buf;
+ const u16 *tx_sbuf;
+
+ pmsg = *ppmsg;
+
+ /* set baud rate if needed */
+ if (data->cur_trans->speed_hz) {
+ dev_dbg(&data->master->dev, "%s:setting baud rate\n", __func__);
+ pch_spi_set_baud_rate(data->master, data->cur_trans->speed_hz);
+ }
+
+ /* set bits per word if needed */
+ if (data->cur_trans->bits_per_word &&
+ (data->current_msg->spi->bits_per_word != data->cur_trans->bits_per_word)) {
+ dev_dbg(&data->master->dev, "%s:set bits per word\n", __func__);
+ pch_spi_set_bits_per_word(data->master,
+ data->cur_trans->bits_per_word);
+ *bpw = data->cur_trans->bits_per_word;
+ } else {
+ *bpw = data->current_msg->spi->bits_per_word;
+ }
+
+ /* reset Tx/Rx index */
+ data->tx_index = 0;
+ data->rx_index = 0;
+
+ data->bpw_len = data->cur_trans->len / (*bpw / 8);
+
+ /* find alloc size */
+ size = data->cur_trans->len * sizeof(*data->pkt_tx_buff);
+
+ /* allocate memory for pkt_tx_buff & pkt_rx_buffer */
+ data->pkt_tx_buff = kzalloc(size, GFP_KERNEL);
+ if (data->pkt_tx_buff != NULL) {
+ data->pkt_rx_buff = kzalloc(size, GFP_KERNEL);
+ if (!data->pkt_rx_buff)
+ kfree(data->pkt_tx_buff);
+ }
+
+ if (!data->pkt_rx_buff) {
+ /* flush queue and set status of all transfers to -ENOMEM */
+ dev_err(&data->master->dev, "%s :kzalloc failed\n", __func__);
+ list_for_each_entry(pmsg, data->queue.next, queue) {
+ pmsg->status = -ENOMEM;
+
+ if (pmsg->complete != 0)
+ pmsg->complete(pmsg->context);
+
+ /* delete from queue */
+ list_del_init(&pmsg->queue);
+ }
+ return;
+ }
+
+ /* copy Tx Data */
+ if (data->cur_trans->tx_buf != NULL) {
+ if (*bpw == 8) {
+ tx_buf = data->cur_trans->tx_buf;
+ for (j = 0; j < data->bpw_len; j++)
+ data->pkt_tx_buff[j] = *tx_buf++;
+ } else {
+ tx_sbuf = data->cur_trans->tx_buf;
+ for (j = 0; j < data->bpw_len; j++)
+ data->pkt_tx_buff[j] = *tx_sbuf++;
+ }
+ }
+
+ /* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */
+ n_writes = data->bpw_len;
+ if (n_writes > PCH_MAX_FIFO_DEPTH)
+ n_writes = PCH_MAX_FIFO_DEPTH;
+
+ dev_dbg(&data->master->dev, "\n%s:Pulling down SSN low - writing "
+ "0x2 to SSNXCR\n", __func__);
+ pch_spi_writereg(data->master, PCH_SSNXCR, SSN_LOW);
+
+ for (j = 0; j < n_writes; j++)
+ pch_spi_writereg(data->master, PCH_SPDWR, data->pkt_tx_buff[j]);
+
+ /* update tx_index */
+ data->tx_index = j;
+
+ /* reset transfer complete flag */
+ data->transfer_complete = false;
+ data->transfer_active = true;
+}
+
+
+static void pch_spi_nomore_transfer(struct pch_spi_data *data,
+ struct spi_message *pmsg)
+{
+ dev_dbg(&data->master->dev, "%s called\n", __func__);
+ /* Invoke complete callback
+ * [To the spi core..indicating end of transfer] */
+ data->current_msg->status = 0;
+
+ if (data->current_msg->complete != 0) {
+ dev_dbg(&data->master->dev,
+ "%s:Invoking callback of SPI core\n", __func__);
+ data->current_msg->complete(data->current_msg->context);
+ }
+
+ /* update status in global variable */
+ data->bcurrent_msg_processing = false;
+
+ dev_dbg(&data->master->dev,
+ "%s:data->bcurrent_msg_processing = false\n", __func__);
+
+ data->current_msg = NULL;
+ data->cur_trans = NULL;
+
+ /* check if we have items in list and not suspending
+ * return 1 if list empty */
+ if ((list_empty(&data->queue) == 0) &&
+ (!data->board_dat->suspend_sts) &&
+ (data->status != STATUS_EXITING)) {
+ /* We have some more work to do (either there is more tranint
+ * bpw;sfer requests in the current message or there are
+ *more messages)
+ */
+ dev_dbg(&data->master->dev, "%s:Invoke queue_work\n", __func__);
+ queue_work(data->wk, &data->work);
+ } else if (data->board_dat->suspend_sts ||
+ data->status == STATUS_EXITING) {
+ dev_dbg(&data->master->dev,
+ "%s suspend/remove initiated, flushing queue\n",
+ __func__);
+ list_for_each_entry(pmsg, data->queue.next, queue) {
+ pmsg->status = -EIO;
+
+ if (pmsg->complete)
+ pmsg->complete(pmsg->context);
+
+ /* delete from queue */
+ list_del_init(&pmsg->queue);
+ }
+ }
+}
+
+static void pch_spi_set_ir(struct pch_spi_data *data)
+{
+ /* enable interrupts */
+ if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) {
+ /* set receive threshold to PCH_RX_THOLD */
+ pch_spi_setclr_reg(data->master, PCH_SPCR,
+ PCH_RX_THOLD << SPCR_RFIC_FIELD,
+ ~MASK_RFIC_SPCR_BITS);
+ /* enable FI and RFI interrupts */
+ pch_spi_setclr_reg(data->master, PCH_SPCR,
+ SPCR_RFIE_BIT | SPCR_FIE_BIT, 0);
+ } else {
+ /* set receive threshold to maximum */
+ pch_spi_setclr_reg(data->master, PCH_SPCR,
+ PCH_RX_THOLD_MAX << SPCR_TFIC_FIELD,
+ ~MASK_TFIC_SPCR_BITS);
+ /* enable FI interrupt */
+ pch_spi_setclr_reg(data->master, PCH_SPCR, SPCR_FIE_BIT, 0);
+ }
+
+ dev_dbg(&data->master->dev,
+ "%s:invoking pch_spi_set_enable to enable SPI\n", __func__);
+
+ /* SPI set enable */
+ pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, SPCR_SPE_BIT, 0);
+
+ /* Wait until the transfer completes; go to sleep after
+ initiating the transfer. */
+ dev_dbg(&data->master->dev,
+ "%s:waiting for transfer to get over\n", __func__);
+
+ wait_event_interruptible(data->wait, data->transfer_complete);
+
+ pch_spi_writereg(data->master, PCH_SSNXCR, SSN_NO_CONTROL);
+ dev_dbg(&data->master->dev,
+ "%s:no more control over SSN-writing 0 to SSNXCR.", __func__);
+
+ data->transfer_active = false;
+ dev_dbg(&data->master->dev,
+ "%s set data->transfer_active = false\n", __func__);
+
+ /* clear all interrupts */
+ pch_spi_writereg(data->master, PCH_SPSR,
+ pch_spi_readreg(data->master, PCH_SPSR));
+ /* disable interrupts */
+ pch_spi_setclr_reg(data->master, PCH_SPCR, 0, PCH_ALL);
+}
+
+static void pch_spi_copy_rx_data(struct pch_spi_data *data, int bpw)
+{
+ int j;
+ u8 *rx_buf;
+ u16 *rx_sbuf;
+
+ /* copy Rx Data */
+ if (!data->cur_trans->rx_buf)
+ return;
+
+ if (bpw == 8) {
+ rx_buf = data->cur_trans->rx_buf;
+ for (j = 0; j < data->bpw_len; j++)
+ *rx_buf++ = data->pkt_rx_buff[j] & 0xFF;
+ } else {
+ rx_sbuf = data->cur_trans->rx_buf;
+ for (j = 0; j < data->bpw_len; j++)
+ *rx_sbuf++ = data->pkt_rx_buff[j];
+ }
+}
+
+
+static void pch_spi_process_messages(struct work_struct *pwork)
+{
+ struct spi_message *pmsg;
+ struct pch_spi_data *data;
+ int bpw;
+
+ data = container_of(pwork, struct pch_spi_data, work);
+ dev_dbg(&data->master->dev, "%s data initialized\n", __func__);
+
+ spin_lock(&data->lock);
+
+ /* check if suspend has been initiated;if yes flush queue */
+ if (data->board_dat->suspend_sts || (data->status == STATUS_EXITING)) {
+ dev_dbg(&data->master->dev,
+ "%s suspend/remove initiated,flushing queue\n",
+ __func__);
+
+ list_for_each_entry(pmsg, data->queue.next, queue) {
+ pmsg->status = -EIO;
+
+ if (pmsg->complete != 0) {
+ spin_unlock(&data->lock);
+ pmsg->complete(pmsg->context);
+ spin_lock(&data->lock);
+ }
+
+ /* delete from queue */
+ list_del_init(&pmsg->queue);
+ }
+
+ spin_unlock(&data->lock);
+ return;
+ }
+
+ data->bcurrent_msg_processing = true;
+ dev_dbg(&data->master->dev,
+ "%s Set data->bcurrent_msg_processing= true\n", __func__);
+
+ /* Get the message from the queue and delete it from there. */
+ data->current_msg = list_entry(data->queue.next, struct spi_message,
+ queue);
+
+ list_del_init(&data->current_msg->queue);
+
+ data->current_msg->status = 0;
+
+ pch_spi_select_chip(data, data->current_msg->spi);
+
+ spin_unlock(&data->lock);
+
+ do {
+ /* If we are already processing a message get the next
+ transfer structure from the message otherwise retrieve
+ the 1st transfer request from the message. */
+ spin_lock(&data->lock);
+
+ if (data->cur_trans == NULL) {
+ data->cur_trans =
+ list_entry(data->current_msg->transfers.
+ next, struct spi_transfer,
+ transfer_list);
+ dev_dbg(&data->master->dev,
+ "%s :Getting 1st transfer message\n", __func__);
+ } else {
+ data->cur_trans =
+ list_entry(data->cur_trans->transfer_list.next,
+ struct spi_transfer,
+ transfer_list);
+ dev_dbg(&data->master->dev,
+ "%s :Getting next transfer message\n",
+ __func__);
+ }
+
+ spin_unlock(&data->lock);
+
+ pch_spi_set_tx(data, &bpw, &pmsg);
+
+ /* Control interrupt*/
+ pch_spi_set_ir(data);
+
+ /* Disable SPI transfer */
+ pch_spi_setclr_reg(data->current_chip->master, PCH_SPCR, 0,
+ SPCR_SPE_BIT);
+
+ /* clear FIFO */
+ pch_spi_clear_fifo(data->master);
+
+ /* copy Rx Data */
+ pch_spi_copy_rx_data(data, bpw);
+
+ /* free memory */
+ kfree(data->pkt_rx_buff);
+ data->pkt_rx_buff = NULL;
+
+ kfree(data->pkt_tx_buff);
+ data->pkt_tx_buff = NULL;
+
+ /* increment message count */
+ data->current_msg->actual_length += data->cur_trans->len;
+
+ dev_dbg(&data->master->dev,
+ "%s:data->current_msg->actual_length=%d\n",
+ __func__, data->current_msg->actual_length);
+
+ /* check for delay */
+ if (data->cur_trans->delay_usecs) {
+ dev_dbg(&data->master->dev, "%s:"
+ "delay in usec=%d\n", __func__,
+ data->cur_trans->delay_usecs);
+ udelay(data->cur_trans->delay_usecs);
+ }
+
+ spin_lock(&data->lock);
+
+ /* No more transfer in this message. */
+ if ((data->cur_trans->transfer_list.next) ==
+ &(data->current_msg->transfers)) {
+ pch_spi_nomore_transfer(data, pmsg);
+ }
+
+ spin_unlock(&data->lock);
+
+ } while (data->cur_trans != NULL);
+}
+
+static void pch_spi_free_resources(struct pch_spi_board_data *board_dat)
+{
+ dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
+
+ /* free workqueue */
+ if (board_dat->data->wk != NULL) {
+ destroy_workqueue(board_dat->data->wk);
+ board_dat->data->wk = NULL;
+ dev_dbg(&board_dat->pdev->dev,
+ "%s destroy_workqueue invoked successfully\n",
+ __func__);
+ }
+
+ /* disable interrupts & free IRQ */
+ if (board_dat->irq_reg_sts) {
+ /* disable interrupts */
+ pch_spi_setclr_reg(board_dat->data->master, PCH_SPCR, 0,
+ PCH_ALL);
+
+ /* free IRQ */
+ free_irq(board_dat->pdev->irq, board_dat);
+
+ dev_dbg(&board_dat->pdev->dev,
+ "%s free_irq invoked successfully\n", __func__);
+
+ board_dat->irq_reg_sts = false;
+ }
+
+ /* unmap PCI base address */
+ if (board_dat->data->io_remap_addr != 0) {
+ pci_iounmap(board_dat->pdev, board_dat->data->io_remap_addr);
+
+ board_dat->data->io_remap_addr = 0;
+
+ dev_dbg(&board_dat->pdev->dev,
+ "%s pci_iounmap invoked successfully\n", __func__);
+ }
+
+ /* release PCI region */
+ if (board_dat->pci_req_sts) {
+ pci_release_regions(board_dat->pdev);
+ dev_dbg(&board_dat->pdev->dev,
+ "%s pci_release_regions invoked successfully\n",
+ __func__);
+ board_dat->pci_req_sts = false;
+ }
+}
+
+static int pch_spi_get_resources(struct pch_spi_board_data *board_dat)
+{
+ void __iomem *io_remap_addr;
+ int retval;
+ dev_dbg(&board_dat->pdev->dev, "%s ENTRY\n", __func__);
+
+ /* create workqueue */
+ board_dat->data->wk = create_singlethread_workqueue(KBUILD_MODNAME);
+ if (!board_dat->data->wk) {
+ dev_err(&board_dat->pdev->dev,
+ "%s create_singlet hread_workqueue failed\n", __func__);
+ retval = -EBUSY;
+ goto err_return;
+ }
+
+ dev_dbg(&board_dat->pdev->dev,
+ "%s create_singlethread_workqueue success\n", __func__);
+
+ retval = pci_request_regions(board_dat->pdev, KBUILD_MODNAME);
+ if (retval != 0) {
+ dev_err(&board_dat->pdev->dev,
+ "%s request_region failed\n", __func__);
+ goto err_return;
+ }
+
+ board_dat->pci_req_sts = true;
+
+ io_remap_addr = pci_iomap(board_dat->pdev, 1, 0);
+ if (io_remap_addr == 0) {
+ dev_err(&board_dat->pdev->dev,
+ "%s pci_iomap failed\n", __func__);
+ retval = -ENOMEM;
+ goto err_return;
+ }
+
+ /* calculate base address for all channels */
+ board_dat->data->io_remap_addr = io_remap_addr;
+
+ /* reset PCH SPI h/w */
+ pch_spi_reset(board_dat->data->master);
+ dev_dbg(&board_dat->pdev->dev,
+ "%s pch_spi_reset invoked successfully\n", __func__);
+
+ /* register IRQ */
+ retval = request_irq(board_dat->pdev->irq, pch_spi_handler,
+ IRQF_SHARED, KBUILD_MODNAME, board_dat);
+ if (retval != 0) {
+ dev_err(&board_dat->pdev->dev,
+ "%s request_irq failed\n", __func__);
+ goto err_return;
+ }
+
+ dev_dbg(&board_dat->pdev->dev, "%s request_irq returned=%d\n",
+ __func__, retval);
+
+ board_dat->irq_reg_sts = true;
+ dev_dbg(&board_dat->pdev->dev, "%s data->irq_reg_sts=true\n", __func__);
+
+err_return:
+ if (retval != 0) {
+ dev_err(&board_dat->pdev->dev,
+ "%s FAIL:invoking pch_spi_free_resources\n", __func__);
+ pch_spi_free_resources(board_dat);
+ }
+
+ dev_dbg(&board_dat->pdev->dev, "%s Return=%d\n", __func__, retval);
+
+ return retval;
+}
+
+static int pch_spi_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+
+ struct spi_master *master;
+
+ struct pch_spi_board_data *board_dat;
+ int retval;
+
+ dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+ /* allocate memory for private data */
+ board_dat = kzalloc(sizeof(struct pch_spi_board_data), GFP_KERNEL);
+ if (board_dat == NULL) {
+ dev_err(&pdev->dev,
+ " %s memory allocation for private data failed\n",
+ __func__);
+ retval = -ENOMEM;
+ goto err_kmalloc;
+ }
+
+ dev_dbg(&pdev->dev,
+ "%s memory allocation for private data success\n", __func__);
+
+ /* enable PCI device */
+ retval = pci_enable_device(pdev);
+ if (retval != 0) {
+ dev_err(&pdev->dev, "%s pci_enable_device FAILED\n", __func__);
+
+ goto err_pci_en_device;
+ }
+
+ dev_dbg(&pdev->dev, "%s pci_enable_device returned=%d\n",
+ __func__, retval);
+
+ board_dat->pdev = pdev;
+
+ /* alllocate memory for SPI master */
+ master = spi_alloc_master(&pdev->dev, sizeof(struct pch_spi_data));
+ if (master == NULL) {
+ retval = -ENOMEM;
+ dev_err(&pdev->dev, "%s Fail.\n", __func__);
+ goto err_spi_alloc_master;
+ }
+
+ dev_dbg(&pdev->dev,
+ "%s spi_alloc_master returned non NULL\n", __func__);
+
+ /* initialize members of SPI master */
+ master->bus_num = -1;
+ master->num_chipselect = PCH_MAX_CS;
+ master->setup = pch_spi_setup;
+ master->transfer = pch_spi_transfer;
+ dev_dbg(&pdev->dev,
+ "%s transfer member of SPI master initialized\n", __func__);
+
+ board_dat->data = spi_master_get_devdata(master);
+
+ board_dat->data->master = master;
+ board_dat->data->n_curnt_chip = 255;
+ board_dat->data->board_dat = board_dat;
+ board_dat->data->status = STATUS_RUNNING;
+
+ INIT_LIST_HEAD(&board_dat->data->queue);
+ spin_lock_init(&board_dat->data->lock);
+ INIT_WORK(&board_dat->data->work, pch_spi_process_messages);
+ init_waitqueue_head(&board_dat->data->wait);
+
+ /* allocate resources for PCH SPI */
+ retval = pch_spi_get_resources(board_dat);
+ if (retval) {
+ dev_err(&pdev->dev, "%s fail(retval=%d)\n", __func__, retval);
+ goto err_spi_get_resources;
+ }
+
+ dev_dbg(&pdev->dev, "%s pch_spi_get_resources returned=%d\n",
+ __func__, retval);
+
+ /* save private data in dev */
+ pci_set_drvdata(pdev, board_dat);
+ dev_dbg(&pdev->dev, "%s invoked pci_set_drvdata\n", __func__);
+
+ /* set master mode */
+ pch_spi_set_master_mode(master);
+ dev_dbg(&pdev->dev,
+ "%s invoked pch_spi_set_master_mode\n", __func__);
+
+ /* Register the controller with the SPI core. */
+ retval = spi_register_master(master);
+ if (retval != 0) {
+ dev_err(&pdev->dev,
+ "%s spi_register_master FAILED\n", __func__);
+ goto err_spi_reg_master;
+ }
+
+ dev_dbg(&pdev->dev, "%s spi_register_master returned=%d\n",
+ __func__, retval);
+
+
+ return 0;
+
+err_spi_reg_master:
+ spi_unregister_master(master);
+err_spi_get_resources:
+err_spi_alloc_master:
+ spi_master_put(master);
+ pci_disable_device(pdev);
+err_pci_en_device:
+ kfree(board_dat);
+err_kmalloc:
+ return retval;
+}
+
+static void pch_spi_remove(struct pci_dev *pdev)
+{
+ struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
+ int count;
+
+ dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+ if (!board_dat) {
+ dev_err(&pdev->dev,
+ "%s pci_get_drvdata returned NULL\n", __func__);
+ return;
+ }
+
+ /* check for any pending messages; no action is taken if the queue
+ * is still full; but at least we tried. Unload anyway */
+ count = 500;
+ spin_lock(&board_dat->data->lock);
+ board_dat->data->status = STATUS_EXITING;
+ while ((list_empty(&board_dat->data->queue) == 0) && --count) {
+ dev_dbg(&board_dat->pdev->dev, "%s :queue not empty\n",
+ __func__);
+ spin_unlock(&board_dat->data->lock);
+ msleep(PCH_SLEEP_TIME);
+ spin_lock(&board_dat->data->lock);
+ }
+ spin_unlock(&board_dat->data->lock);
+
+ /* Free resources allocated for PCH SPI */
+ pch_spi_free_resources(board_dat);
+
+ spi_unregister_master(board_dat->data->master);
+
+ /* free memory for private data */
+ kfree(board_dat);
+
+ pci_set_drvdata(pdev, NULL);
+
+ /* disable PCI device */
+ pci_disable_device(pdev);
+
+ dev_dbg(&pdev->dev, "%s invoked pci_disable_device\n", __func__);
+}
+
+#ifdef CONFIG_PM
+static int pch_spi_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+ u8 count;
+ int retval;
+
+ struct pch_spi_board_data *board_dat = pci_get_drvdata(pdev);
+
+ dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+ if (!board_dat) {
+ dev_err(&pdev->dev,
+ "%s pci_get_drvdata returned NULL\n", __func__);
+ return -EFAULT;
+ }
+
+ retval = 0;
+ board_dat->suspend_sts = true;
+
+ /* check if the current message is processed:
+ Only after thats done the transfer will be suspended */
+ count = 255;
+ while ((--count) > 0) {
+ if (!(board_dat->data->bcurrent_msg_processing)) {
+ dev_dbg(&pdev->dev, "%s board_dat->data->bCurrent_"
+ "msg_processing = false\n", __func__);
+ break;
+ } else {
+ dev_dbg(&pdev->dev, "%s board_dat->data->bCurrent_msg_"
+ "processing = true\n", __func__);
+ }
+ msleep(PCH_SLEEP_TIME);
+ }
+
+ /* Free IRQ */
+ if (board_dat->irq_reg_sts) {
+ /* disable all interrupts */
+ pch_spi_setclr_reg(board_dat->data->master, PCH_SPCR, 0,
+ PCH_ALL);
+ pch_spi_reset(board_dat->data->master);
+
+ free_irq(board_dat->pdev->irq, board_dat);
+
+ board_dat->irq_reg_sts = false;
+ dev_dbg(&pdev->dev,
+ "%s free_irq invoked successfully.\n", __func__);
+ }
+
+ /* save config space */
+ retval = pci_save_state(pdev);
+
+ if (retval == 0) {
+ dev_dbg(&pdev->dev, "%s pci_save_state returned=%d\n",
+ __func__, retval);
+ /* disable PM notifications */
+ pci_enable_wake(pdev, PCI_D3hot, 0);
+ dev_dbg(&pdev->dev,
+ "%s pci_enable_wake invoked successfully\n", __func__);
+ /* disable PCI device */
+ pci_disable_device(pdev);
+ dev_dbg(&pdev->dev,
+ "%s pci_disable_device invoked successfully\n",
+ __func__);
+ /* move device to D3hot state */
+ pci_set_power_state(pdev, PCI_D3hot);
+ dev_dbg(&pdev->dev,
+ "%s pci_set_power_state invoked successfully\n",
+ __func__);
+ } else {
+ dev_err(&pdev->dev, "%s pci_save_state failed\n", __func__);
+ }
+
+ dev_dbg(&pdev->dev, "%s return=%d\n", __func__, retval);
+
+ return retval;
+}
+
+static int pch_spi_resume(struct pci_dev *pdev)
+{
+ int retval;
+
+ struct pch_spi_board_data *board = pci_get_drvdata(pdev);
+ dev_dbg(&pdev->dev, "%s ENTRY\n", __func__);
+
+ if (!board) {
+ dev_err(&pdev->dev,
+ "%s pci_get_drvdata returned NULL\n", __func__);
+ return -EFAULT;
+ }
+
+ /* move device to DO power state */
+ pci_set_power_state(pdev, PCI_D0);
+
+ /* restore state */
+ pci_restore_state(pdev);
+
+ retval = pci_enable_device(pdev);
+ if (retval < 0) {
+ dev_err(&pdev->dev,
+ "%s pci_enable_device failed\n", __func__);
+ } else {
+ /* disable PM notifications */
+ pci_enable_wake(pdev, PCI_D3hot, 0);
+
+ /* register IRQ handler */
+ if (!board->irq_reg_sts) {
+ /* register IRQ */
+ retval = request_irq(board->pdev->irq, pch_spi_handler,
+ IRQF_SHARED, KBUILD_MODNAME,
+ board);
+ if (retval < 0) {
+ dev_err(&pdev->dev,
+ "%s request_irq failed\n", __func__);
+ return retval;
+ }
+ board->irq_reg_sts = true;
+
+ /* reset PCH SPI h/w */
+ pch_spi_reset(board->data->master);
+ pch_spi_set_master_mode(board->data->master);
+
+ /* set suspend status to false */
+ board->suspend_sts = false;
+
+ }
+ }
+
+ dev_dbg(&pdev->dev, "%s returning=%d\n", __func__, retval);
+
+ return retval;
+}
+#else
+#define pch_spi_suspend NULL
+#define pch_spi_resume NULL
+
+#endif
+
+static struct pci_driver pch_spi_pcidev = {
+ .name = "pch_spi",
+ .id_table = pch_spi_pcidev_id,
+ .probe = pch_spi_probe,
+ .remove = pch_spi_remove,
+ .suspend = pch_spi_suspend,
+ .resume = pch_spi_resume,
+};
+
+static int __init pch_spi_init(void)
+{
+ return pci_register_driver(&pch_spi_pcidev);
+}
+module_init(pch_spi_init);
+
+static void __exit pch_spi_exit(void)
+{
+ pci_unregister_driver(&pch_spi_pcidev);
+}
+module_exit(pch_spi_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Topcliff PCH SPI PCI Driver");