/* * 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 #include #include #include #include #include #include #include /* 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_RX 1 #define PCH_TX 2 /* various interrupts */ #define PCH_TFI 0x1 #define PCH_RFI 0x2 #define PCH_FI 0x4 #define PCH_ORI 0x8 #define PCH_MDFI 0x10 #define PCH_ALL (PCH_TFI|PCH_RFI|PCH_FI|PCH_ORI|PCH_MDFI) #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 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,} }; static inline void pch_set_bitmsk(u32 *var, u32 bitmask) { *var |= bitmask; } static inline void pch_clr_bitmsk(u32 *var, u32 bitmask) { *var &= (~(bitmask)); } /** * 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); } /* ope==true:Set bit, ope==false:Clear bit */ static inline void pch_spi_setclr_bit(u32 *val, u32 pos, bool ope) { if (ope) *val |= pos; else *val &= (~(pos)); } 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); } /** * ch_spi_disable_interrupts() - Disables specified interrupts * @master: Pointer to struct spi_master. * @interrupt: Interrups to be enabled. */ static void pch_spi_disable_interrupts(struct spi_master *master, u8 interrupt) { u32 clr_flags = 0; if (interrupt & PCH_RFI) clr_flags |= SPCR_RFIE_BIT; if (interrupt & PCH_TFI) clr_flags |= SPCR_TFIE_BIT; if (interrupt & PCH_FI) clr_flags |= SPCR_FIE_BIT; if (interrupt & PCH_ORI) clr_flags |= SPCR_ORIE_BIT; if (interrupt & PCH_MDFI) clr_flags |= SPCR_MDFIE_BIT; pch_spi_setclr_reg(master, PCH_SPCR, 0, clr_flags); dev_dbg(&master->dev, "%s clearing bits =%x\n", __func__, clr_flags); } 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); /* disable RFI */ pch_clr_bitmsk(®_spcr_val, SPCR_RFIE_BIT); /* 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_disable_interrupts(data->master, PCH_FI | PCH_RFI); /* 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; 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 reg_spcr_val; 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) pch_spi_setclr_reg(spi->master, PCH_SPCR, 0, SPCR_LSBF_BIT); else pch_spi_setclr_reg(spi->master, PCH_SPCR, SPCR_LSBF_BIT, 0); if (spi->mode & SPI_CPOL) pch_spi_setclr_reg(spi->master, PCH_SPCR, SPCR_CPOL_BIT, 0); else pch_spi_setclr_reg(spi->master, PCH_SPCR, 0, SPCR_CPOL_BIT); if (spi->mode & SPI_CPHA) pch_spi_setclr_reg(spi->master, PCH_SPCR, SPCR_CPHA_BIT, 0); else pch_spi_setclr_reg(spi->master, PCH_SPCR, 0, SPCR_CPHA_BIT); dev_dbg(&spi->dev, "%s SPCR content after setting LSB/MSB and MODE= %x\n", __func__, reg_spcr_val); /* Clear the FIFO by toggling FICLR to 1 and back to 0 */ pch_spi_clear_fifo(spi->master); } /** * pch_spi_enable_interrupts() - Enables specified interrupts * @master: Pointer to struct spi_master. * @interrupt: Interrups to be enabled. */ static void pch_spi_enable_interrupts(struct spi_master *master, u8 interrupt) { u32 reg_val_spcr; dev_dbg(&master->dev, "%s SPCR content=%x\n", __func__, reg_val_spcr); if (interrupt & PCH_RFI) { /* set RFIE bit in SPCR */ dev_dbg(&master->dev, "setting RFI in %s\n", __func__); pch_spi_setclr_reg(master, PCH_SPCR, SPCR_RFIE_BIT, 0); } if (interrupt & PCH_TFI) { /* set TFIE bit in SPCR */ dev_dbg(&master->dev, "setting TFI in %s\n", __func__); pch_spi_setclr_reg(master, PCH_SPCR, SPCR_TFIE_BIT, 0); } if (interrupt & PCH_FI) { /* set FIE bit in SPCR */ dev_dbg(&master->dev, "setting FI in %s\n", __func__); pch_spi_setclr_reg(master, PCH_SPCR, SPCR_FIE_BIT, 0); } if (interrupt & PCH_ORI) { /* set ORIE bit in SPCR */ dev_dbg(&master->dev, "setting ORI in %s\n", __func__); pch_spi_setclr_reg(master, PCH_SPCR, SPCR_ORIE_BIT, 0); } if (interrupt & PCH_MDFI) { /* set MODFIE bit in SPCR */ dev_dbg(&master->dev, "setting MDFI in %s\n", __func__); pch_spi_setclr_reg(master, PCH_SPCR, SPCR_MDFIE_BIT, 0); } } /** * pch_spi_set_threshold() - Sets Tx/Rx FIFO thresholds * @spi: Pointer to struct spi_device. * @threshold: Threshold value to be set. * @dir: Rx or Tx threshold to be set. */ static void pch_spi_set_threshold(struct spi_device *spi, u32 threshold, u8 dir) { if (dir == PCH_RX) { dev_dbg(&spi->dev, "%s setting Rx threshold\n", __func__); pch_spi_setclr_reg(spi->master, PCH_SPCR, threshold << SPCR_RFIC_FIELD, ~MASK_RFIC_SPCR_BITS); } else if (dir == PCH_TX) { dev_dbg(&spi->dev, "%s setting Tx threshold\n", __func__); pch_spi_setclr_reg(spi->master, PCH_SPCR, (threshold << SPCR_TFIC_FIELD) , ~MASK_TFIC_SPCR_BITS); } } /** * 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) || (pspi->max_speed_hz == 0))) { if (list_empty(&pmsg->transfers) == 1) dev_err(&pspi->dev, "%s list empty\n", __func__); if ((pspi->max_speed_hz) == 0) { dev_err(&pspi->dev, "%s pch_spi_tranfer maxspeed=%d\n", __func__, pspi->max_speed_hz); } dev_err(&pspi->dev, "%s returning EINVAL\n", __func__); retval = -EINVAL; goto err_out; } dev_dbg(&pspi->dev, "%s Transfer List not empty. " "Transfer Speed is set.\n", __func__); spin_lock_irqsave(&data->lock, flags); /* 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_return_spinlock; } if (!(transfer->len)) { dev_err(&pspi->dev, "%s Transfer length invalid\n", __func__); retval = -EINVAL; goto err_return_spinlock; } 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) { 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_return_spinlock; } } } /* We won't process any messages if we have been asked to terminate */ if (STATUS_EXITING == (data->status)) { 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 bSuspending= true 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-Invoking\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 b_mem_fail; 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:pctrldatasetting 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:setting 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); b_mem_fail = false; /* 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 == NULL) { b_mem_fail = true; kfree(data->pkt_tx_buff); } } else { b_mem_fail = true; } if (b_mem_fail) { /* flush queue and set status of all transfers to -ENOMEM */ dev_err(&data->master->dev, "Kzalloc fail in %s messages\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) { for (j = 0; j < (data->bpw_len); j++) { tx_buf = data->cur_trans->tx_buf; data->pkt_tx_buff[j] = tx_buf[j]; } } else { for (j = 0; j < (data->bpw_len); j++) { tx_sbuf = data->cur_trans->tx_buf; data->pkt_tx_buff[j] = tx_sbuf[j]; } } } /* if len greater than PCH_MAX_FIFO_DEPTH, write 16,else len bytes */ if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) n_writes = PCH_MAX_FIFO_DEPTH; else n_writes = (data->bpw_len); 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:no more transfers in this message\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:we have pending messages-Invoking 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 != 0) pmsg->complete(pmsg->context); /* delete from queue */ list_del_init(&pmsg->queue); } } } static void pch_spi_set_ir(struct pch_spi_data *data) { u32 reg_spcr_val; /* enable interrupts */ if ((data->bpw_len) > PCH_MAX_FIFO_DEPTH) { /* set receive threhold to PCH_RX_THOLD */ pch_spi_set_threshold(data->current_chip, PCH_RX_THOLD, PCH_RX); /* enable FI and RFI interrupts */ pch_spi_enable_interrupts(data->master, PCH_RFI | PCH_FI); } else { /* set receive threhold to maximum */ pch_spi_set_threshold(data->current_chip, PCH_RX_THOLD_MAX, PCH_RX); /* enable FI interrupt */ pch_spi_enable_interrupts(data->master, PCH_FI); } dev_dbg(&data->master->dev, "%s:invoking pch_spi_set_enable to enable SPI\n", __func__); /* SPI set enable */ reg_spcr_val = pch_spi_readreg(data->current_chip->master, PCH_SPCR); pch_set_bitmsk(®_spcr_val, SPCR_SPE_BIT); pch_spi_writereg(data->current_chip->master, PCH_SPCR, reg_spcr_val); /* 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_disable_interrupts(data->master, 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) { for (j = 0; j < (data->bpw_len); j++) { rx_buf = data->cur_trans->rx_buf; rx_buf[j] = (data->pkt_rx_buff[j]) & 0xFF; } } else { for (j = 0; j < (data->bpw_len); j++) { rx_sbuf = data->cur_trans->rx_buf; rx_sbuf[j] = data->pkt_rx_buff[j]; } } } static void pch_spi_process_messages(struct work_struct *pwork) { struct spi_message *pmsg; int bpw; struct pch_spi_data *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_disable_interrupts(board_dat->data-> master, PCH_ALL); dev_dbg(&board_dat->pdev->dev, "%s pch_spi_disable_interrupts invoked " "successfully\n", __func__); /* free IRQ */ free_irq(board_dat->pdev->irq, (void *)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__); /* iniatize queue of pending messages */ INIT_LIST_HEAD(&(board_dat->data->queue)); /* initialize spin locks */ spin_lock_init(&(board_dat->data->lock)); /* set channel status */ board_dat->data->status = STATUS_RUNNING; /* initialize work structure */ INIT_WORK(&(board_dat->data->work), pch_spi_process_messages); /* initialize wait queues */ init_waitqueue_head(&(board_dat->data->wait)); /* create workqueue */ board_dat->data->wk = create_singlethread_workqueue(KBUILD_MODNAME); if ((board_dat->data->wk) == NULL) { 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, (void *)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_check_request_pending(struct pch_spi_board_data *board_dat) { int sts; u16 count; 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)); if (count) { sts = 0; dev_dbg(&board_dat->pdev->dev, "%s :queue empty\n", __func__); } else { sts = -EBUSY; } dev_dbg(&board_dat->pdev->dev, "%s : EXIT=%d\n", __func__, sts); return sts; } 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; /* allocate resources for PCH SPI */ retval = pch_spi_get_resources(board_dat); if (retval != 0) { 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, (void *)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); 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 */ if ((-EBUSY) == pch_spi_check_request_pending(board_dat)) { dev_dbg(&pdev->dev, "%s pch_spi_check_request_pending returned" " EBUSY\n", __func__); /* no need to take any particular action; proceed with remove even though queue is not empty */ } /* Free resources allocated for PCH SPI */ pch_spi_free_resources(board_dat); /* Unregister SPI master */ 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_disable_interrupts(board_dat->data->master, PCH_ALL); pch_spi_reset(board_dat->data->master); dev_dbg(&pdev->dev, "%s pch_spi_disable_interrupts invoked successfully\n", __func__); free_irq(board_dat->pdev->irq, (void *)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("PCH SPI PCI Driver");