diff options
Diffstat (limited to 'drivers/spi/spi-topcliff-pch.c')
| -rw-r--r-- | drivers/spi/spi-topcliff-pch.c | 1303 |
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 000000000000..79e48d451137 --- /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"); |