--- /dev/null
+/*
+ * Analog Devices SPI3 controller driver
+ *
+ * Copyright (c) 2013 Analog Devices Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/gpio.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/types.h>
+
+#include <asm/bfin_spi3.h>
+#include <asm/cacheflush.h>
+#include <asm/dma.h>
+#include <asm/portmux.h>
+
+enum bfin_spi_state {
+ START_STATE,
+ RUNNING_STATE,
+ DONE_STATE,
+ ERROR_STATE
+};
+
+struct bfin_spi_master;
+
+struct bfin_spi_transfer_ops {
+ void (*write) (struct bfin_spi_master *);
+ void (*read) (struct bfin_spi_master *);
+ void (*duplex) (struct bfin_spi_master *);
+};
+
+/* runtime info for spi master */
+struct bfin_spi_master {
+ /* SPI framework hookup */
+ struct spi_master *master;
+
+ /* Regs base of SPI controller */
+ struct bfin_spi_regs __iomem *regs;
+
+ /* Pin request list */
+ u16 *pin_req;
+
+ /* Message Transfer pump */
+ struct tasklet_struct pump_transfers;
+
+ /* Current message transfer state info */
+ struct spi_message *cur_msg;
+ struct spi_transfer *cur_transfer;
+ struct bfin_spi_device *cur_chip;
+ unsigned transfer_len;
+
+ /* transfer buffer */
+ void *tx;
+ void *tx_end;
+ void *rx;
+ void *rx_end;
+
+ /* dma info */
+ unsigned int tx_dma;
+ unsigned int rx_dma;
+ dma_addr_t tx_dma_addr;
+ dma_addr_t rx_dma_addr;
+ unsigned long dummy_buffer; /* used in unidirectional transfer */
+ unsigned long tx_dma_size;
+ unsigned long rx_dma_size;
+ int tx_num;
+ int rx_num;
+
+ /* store register value for suspend/resume */
+ u32 control;
+ u32 ssel;
+
+ unsigned long sclk;
+ enum bfin_spi_state state;
+
+ const struct bfin_spi_transfer_ops *ops;
+};
+
+struct bfin_spi_device {
+ u32 control;
+ u32 clock;
+ u32 ssel;
+
+ u8 cs;
+ u16 cs_chg_udelay; /* Some devices require > 255usec delay */
+ u32 cs_gpio;
+ u32 tx_dummy_val; /* tx value for rx only transfer */
+ bool enable_dma;
+ const struct bfin_spi_transfer_ops *ops;
+};
+
+static void bfin_spi_enable(struct bfin_spi_master *drv_data)
+{
+ bfin_write_or(&drv_data->regs->control, SPI_CTL_EN);
+}
+
+static void bfin_spi_disable(struct bfin_spi_master *drv_data)
+{
+ bfin_write_and(&drv_data->regs->control, ~SPI_CTL_EN);
+}
+
+/* Caculate the SPI_CLOCK register value based on input HZ */
+static u32 hz_to_spi_clock(u32 sclk, u32 speed_hz)
+{
+ u32 spi_clock = sclk / speed_hz;
+
+ if (spi_clock)
+ spi_clock--;
+ return spi_clock;
+}
+
+static int bfin_spi_flush(struct bfin_spi_master *drv_data)
+{
+ unsigned long limit = loops_per_jiffy << 1;
+
+ /* wait for stop and clear stat */
+ while (!(bfin_read(&drv_data->regs->status) & SPI_STAT_SPIF) && --limit)
+ cpu_relax();
+
+ bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
+
+ return limit;
+}
+
+/* Chip select operation functions for cs_change flag */
+static void bfin_spi_cs_active(struct bfin_spi_master *drv_data, struct bfin_spi_device *chip)
+{
+ if (likely(chip->cs < MAX_CTRL_CS))
+ bfin_write_and(&drv_data->regs->ssel, ~chip->ssel);
+ else
+ gpio_set_value(chip->cs_gpio, 0);
+}
+
+static void bfin_spi_cs_deactive(struct bfin_spi_master *drv_data,
+ struct bfin_spi_device *chip)
+{
+ if (likely(chip->cs < MAX_CTRL_CS))
+ bfin_write_or(&drv_data->regs->ssel, chip->ssel);
+ else
+ gpio_set_value(chip->cs_gpio, 1);
+
+ /* Move delay here for consistency */
+ if (chip->cs_chg_udelay)
+ udelay(chip->cs_chg_udelay);
+}
+
+/* enable or disable the pin muxed by GPIO and SPI CS to work as SPI CS */
+static inline void bfin_spi_cs_enable(struct bfin_spi_master *drv_data,
+ struct bfin_spi_device *chip)
+{
+ if (chip->cs < MAX_CTRL_CS)
+ bfin_write_or(&drv_data->regs->ssel, chip->ssel >> 8);
+}
+
+static inline void bfin_spi_cs_disable(struct bfin_spi_master *drv_data,
+ struct bfin_spi_device *chip)
+{
+ if (chip->cs < MAX_CTRL_CS)
+ bfin_write_and(&drv_data->regs->ssel, ~(chip->ssel >> 8));
+}
+
+/* stop controller and re-config current chip*/
+static void bfin_spi_restore_state(struct bfin_spi_master *drv_data)
+{
+ struct bfin_spi_device *chip = drv_data->cur_chip;
+
+ /* Clear status and disable clock */
+ bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
+ bfin_write(&drv_data->regs->rx_control, 0x0);
+ bfin_write(&drv_data->regs->tx_control, 0x0);
+ bfin_spi_disable(drv_data);
+
+ SSYNC();
+
+ /* Load the registers */
+ bfin_write(&drv_data->regs->control, chip->control);
+ bfin_write(&drv_data->regs->clock, chip->clock);
+
+ bfin_spi_enable(drv_data);
+ drv_data->tx_num = drv_data->rx_num = 0;
+ /* we always choose tx transfer initiate */
+ bfin_write(&drv_data->regs->rx_control, SPI_RXCTL_REN);
+ bfin_write(&drv_data->regs->tx_control,
+ SPI_TXCTL_TEN | SPI_TXCTL_TTI);
+ bfin_spi_cs_active(drv_data, chip);
+}
+
+/* discard invalid rx data and empty rfifo */
+static inline void dummy_read(struct bfin_spi_master *drv_data)
+{
+ while (!(bfin_read(&drv_data->regs->status) & SPI_STAT_RFE))
+ bfin_read(&drv_data->regs->rfifo);
+}
+
+static void bfin_spi_u8_write(struct bfin_spi_master *drv_data)
+{
+ dummy_read(drv_data);
+ while (drv_data->tx < drv_data->tx_end) {
+ bfin_write(&drv_data->regs->tfifo, (*(u8 *)(drv_data->tx++)));
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ bfin_read(&drv_data->regs->rfifo);
+ }
+}
+
+static void bfin_spi_u8_read(struct bfin_spi_master *drv_data)
+{
+ u32 tx_val = drv_data->cur_chip->tx_dummy_val;
+
+ dummy_read(drv_data);
+ while (drv_data->rx < drv_data->rx_end) {
+ bfin_write(&drv_data->regs->tfifo, tx_val);
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ *(u8 *)(drv_data->rx++) = bfin_read(&drv_data->regs->rfifo);
+ }
+}
+
+static void bfin_spi_u8_duplex(struct bfin_spi_master *drv_data)
+{
+ dummy_read(drv_data);
+ while (drv_data->rx < drv_data->rx_end) {
+ bfin_write(&drv_data->regs->tfifo, (*(u8 *)(drv_data->tx++)));
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ *(u8 *)(drv_data->rx++) = bfin_read(&drv_data->regs->rfifo);
+ }
+}
+
+static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u8 = {
+ .write = bfin_spi_u8_write,
+ .read = bfin_spi_u8_read,
+ .duplex = bfin_spi_u8_duplex,
+};
+
+static void bfin_spi_u16_write(struct bfin_spi_master *drv_data)
+{
+ dummy_read(drv_data);
+ while (drv_data->tx < drv_data->tx_end) {
+ bfin_write(&drv_data->regs->tfifo, (*(u16 *)drv_data->tx));
+ drv_data->tx += 2;
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ bfin_read(&drv_data->regs->rfifo);
+ }
+}
+
+static void bfin_spi_u16_read(struct bfin_spi_master *drv_data)
+{
+ u32 tx_val = drv_data->cur_chip->tx_dummy_val;
+
+ dummy_read(drv_data);
+ while (drv_data->rx < drv_data->rx_end) {
+ bfin_write(&drv_data->regs->tfifo, tx_val);
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ *(u16 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
+ drv_data->rx += 2;
+ }
+}
+
+static void bfin_spi_u16_duplex(struct bfin_spi_master *drv_data)
+{
+ dummy_read(drv_data);
+ while (drv_data->rx < drv_data->rx_end) {
+ bfin_write(&drv_data->regs->tfifo, (*(u16 *)drv_data->tx));
+ drv_data->tx += 2;
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ *(u16 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
+ drv_data->rx += 2;
+ }
+}
+
+static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u16 = {
+ .write = bfin_spi_u16_write,
+ .read = bfin_spi_u16_read,
+ .duplex = bfin_spi_u16_duplex,
+};
+
+static void bfin_spi_u32_write(struct bfin_spi_master *drv_data)
+{
+ dummy_read(drv_data);
+ while (drv_data->tx < drv_data->tx_end) {
+ bfin_write(&drv_data->regs->tfifo, (*(u32 *)drv_data->tx));
+ drv_data->tx += 4;
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ bfin_read(&drv_data->regs->rfifo);
+ }
+}
+
+static void bfin_spi_u32_read(struct bfin_spi_master *drv_data)
+{
+ u32 tx_val = drv_data->cur_chip->tx_dummy_val;
+
+ dummy_read(drv_data);
+ while (drv_data->rx < drv_data->rx_end) {
+ bfin_write(&drv_data->regs->tfifo, tx_val);
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ *(u32 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
+ drv_data->rx += 4;
+ }
+}
+
+static void bfin_spi_u32_duplex(struct bfin_spi_master *drv_data)
+{
+ dummy_read(drv_data);
+ while (drv_data->rx < drv_data->rx_end) {
+ bfin_write(&drv_data->regs->tfifo, (*(u32 *)drv_data->tx));
+ drv_data->tx += 4;
+ while (bfin_read(&drv_data->regs->status) & SPI_STAT_RFE)
+ cpu_relax();
+ *(u32 *)drv_data->rx = bfin_read(&drv_data->regs->rfifo);
+ drv_data->rx += 4;
+ }
+}
+
+static const struct bfin_spi_transfer_ops bfin_bfin_spi_transfer_ops_u32 = {
+ .write = bfin_spi_u32_write,
+ .read = bfin_spi_u32_read,
+ .duplex = bfin_spi_u32_duplex,
+};
+
+
+/* test if there is more transfer to be done */
+static void bfin_spi_next_transfer(struct bfin_spi_master *drv)
+{
+ struct spi_message *msg = drv->cur_msg;
+ struct spi_transfer *t = drv->cur_transfer;
+
+ /* Move to next transfer */
+ if (t->transfer_list.next != &msg->transfers) {
+ drv->cur_transfer = list_entry(t->transfer_list.next,
+ struct spi_transfer, transfer_list);
+ drv->state = RUNNING_STATE;
+ } else {
+ drv->state = DONE_STATE;
+ drv->cur_transfer = NULL;
+ }
+}
+
+static void bfin_spi_giveback(struct bfin_spi_master *drv_data)
+{
+ struct bfin_spi_device *chip = drv_data->cur_chip;
+
+ bfin_spi_cs_deactive(drv_data, chip);
+ spi_finalize_current_message(drv_data->master);
+}
+
+static int bfin_spi_setup_transfer(struct bfin_spi_master *drv)
+{
+ struct spi_transfer *t = drv->cur_transfer;
+ u32 cr, cr_width;
+
+ if (t->tx_buf) {
+ drv->tx = (void *)t->tx_buf;
+ drv->tx_end = drv->tx + t->len;
+ } else {
+ drv->tx = NULL;
+ }
+
+ if (t->rx_buf) {
+ drv->rx = t->rx_buf;
+ drv->rx_end = drv->rx + t->len;
+ } else {
+ drv->rx = NULL;
+ }
+
+ drv->transfer_len = t->len;
+
+ /* bits per word setup */
+ switch (t->bits_per_word) {
+ case 8:
+ cr_width = SPI_CTL_SIZE08;
+ drv->ops = &bfin_bfin_spi_transfer_ops_u8;
+ break;
+ case 16:
+ cr_width = SPI_CTL_SIZE16;
+ drv->ops = &bfin_bfin_spi_transfer_ops_u16;
+ break;
+ case 32:
+ cr_width = SPI_CTL_SIZE32;
+ drv->ops = &bfin_bfin_spi_transfer_ops_u32;
+ break;
+ default:
+ return -EINVAL;
+ }
+ cr = bfin_read(&drv->regs->control) & ~SPI_CTL_SIZE;
+ cr |= cr_width;
+ bfin_write(&drv->regs->control, cr);
+
+ /* speed setup */
+ bfin_write(&drv->regs->clock,
+ hz_to_spi_clock(drv->sclk, t->speed_hz));
+ return 0;
+}
+
+static int bfin_spi_dma_xfer(struct bfin_spi_master *drv_data)
+{
+ struct spi_transfer *t = drv_data->cur_transfer;
+ struct spi_message *msg = drv_data->cur_msg;
+ struct bfin_spi_device *chip = drv_data->cur_chip;
+ u32 dma_config;
+ unsigned long word_count, word_size;
+ void *tx_buf, *rx_buf;
+
+ switch (t->bits_per_word) {
+ case 8:
+ dma_config = WDSIZE_8 | PSIZE_8;
+ word_count = drv_data->transfer_len;
+ word_size = 1;
+ break;
+ case 16:
+ dma_config = WDSIZE_16 | PSIZE_16;
+ word_count = drv_data->transfer_len / 2;
+ word_size = 2;
+ break;
+ default:
+ dma_config = WDSIZE_32 | PSIZE_32;
+ word_count = drv_data->transfer_len / 4;
+ word_size = 4;
+ break;
+ }
+
+ if (!drv_data->rx) {
+ tx_buf = drv_data->tx;
+ rx_buf = &drv_data->dummy_buffer;
+ drv_data->tx_dma_size = drv_data->transfer_len;
+ drv_data->rx_dma_size = sizeof(drv_data->dummy_buffer);
+ set_dma_x_modify(drv_data->tx_dma, word_size);
+ set_dma_x_modify(drv_data->rx_dma, 0);
+ } else if (!drv_data->tx) {
+ drv_data->dummy_buffer = chip->tx_dummy_val;
+ tx_buf = &drv_data->dummy_buffer;
+ rx_buf = drv_data->rx;
+ drv_data->tx_dma_size = sizeof(drv_data->dummy_buffer);
+ drv_data->rx_dma_size = drv_data->transfer_len;
+ set_dma_x_modify(drv_data->tx_dma, 0);
+ set_dma_x_modify(drv_data->rx_dma, word_size);
+ } else {
+ tx_buf = drv_data->tx;
+ rx_buf = drv_data->rx;
+ drv_data->tx_dma_size = drv_data->rx_dma_size
+ = drv_data->transfer_len;
+ set_dma_x_modify(drv_data->tx_dma, word_size);
+ set_dma_x_modify(drv_data->rx_dma, word_size);
+ }
+
+ drv_data->tx_dma_addr = dma_map_single(&msg->spi->dev,
+ (void *)tx_buf,
+ drv_data->tx_dma_size,
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(&msg->spi->dev,
+ drv_data->tx_dma_addr))
+ return -ENOMEM;
+
+ drv_data->rx_dma_addr = dma_map_single(&msg->spi->dev,
+ (void *)rx_buf,
+ drv_data->rx_dma_size,
+ DMA_FROM_DEVICE);
+ if (dma_mapping_error(&msg->spi->dev,
+ drv_data->rx_dma_addr)) {
+ dma_unmap_single(&msg->spi->dev,
+ drv_data->tx_dma_addr,
+ drv_data->tx_dma_size,
+ DMA_TO_DEVICE);
+ return -ENOMEM;
+ }
+
+ dummy_read(drv_data);
+ set_dma_x_count(drv_data->tx_dma, word_count);
+ set_dma_x_count(drv_data->rx_dma, word_count);
+ set_dma_start_addr(drv_data->tx_dma, drv_data->tx_dma_addr);
+ set_dma_start_addr(drv_data->rx_dma, drv_data->rx_dma_addr);
+ dma_config |= DMAFLOW_STOP | RESTART | DI_EN;
+ set_dma_config(drv_data->tx_dma, dma_config);
+ set_dma_config(drv_data->rx_dma, dma_config | WNR);
+ enable_dma(drv_data->tx_dma);
+ enable_dma(drv_data->rx_dma);
+ SSYNC();
+
+ bfin_write(&drv_data->regs->rx_control, SPI_RXCTL_REN | SPI_RXCTL_RDR_NE);
+ SSYNC();
+ bfin_write(&drv_data->regs->tx_control,
+ SPI_TXCTL_TEN | SPI_TXCTL_TTI | SPI_TXCTL_TDR_NF);
+
+ return 0;
+}
+
+static int bfin_spi_pio_xfer(struct bfin_spi_master *drv_data)
+{
+ struct spi_message *msg = drv_data->cur_msg;
+
+ if (!drv_data->rx) {
+ /* write only half duplex */
+ drv_data->ops->write(drv_data);
+ if (drv_data->tx != drv_data->tx_end)
+ return -EIO;
+ } else if (!drv_data->tx) {
+ /* read only half duplex */
+ drv_data->ops->read(drv_data);
+ if (drv_data->rx != drv_data->rx_end)
+ return -EIO;
+ } else {
+ /* full duplex mode */
+ drv_data->ops->duplex(drv_data);
+ if (drv_data->tx != drv_data->tx_end)
+ return -EIO;
+ }
+
+ if (!bfin_spi_flush(drv_data))
+ return -EIO;
+ msg->actual_length += drv_data->transfer_len;
+ tasklet_schedule(&drv_data->pump_transfers);
+ return 0;
+}
+
+static void bfin_spi_pump_transfers(unsigned long data)
+{
+ struct bfin_spi_master *drv_data = (struct bfin_spi_master *)data;
+ struct spi_message *msg = NULL;
+ struct spi_transfer *t = NULL;
+ struct bfin_spi_device *chip = NULL;
+ int ret;
+
+ /* Get current state information */
+ msg = drv_data->cur_msg;
+ t = drv_data->cur_transfer;
+ chip = drv_data->cur_chip;
+
+ /* Handle for abort */
+ if (drv_data->state == ERROR_STATE) {
+ msg->status = -EIO;
+ bfin_spi_giveback(drv_data);
+ return;
+ }
+
+ if (drv_data->state == RUNNING_STATE) {
+ if (t->delay_usecs)
+ udelay(t->delay_usecs);
+ if (t->cs_change)
+ bfin_spi_cs_deactive(drv_data, chip);
+ bfin_spi_next_transfer(drv_data);
+ t = drv_data->cur_transfer;
+ }
+ /* Handle end of message */
+ if (drv_data->state == DONE_STATE) {
+ msg->status = 0;
+ bfin_spi_giveback(drv_data);
+ return;
+ }
+
+ if ((t->len == 0) || (t->tx_buf == NULL && t->rx_buf == NULL)) {
+ /* Schedule next transfer tasklet */
+ tasklet_schedule(&drv_data->pump_transfers);
+ return;
+ }
+
+ ret = bfin_spi_setup_transfer(drv_data);
+ if (ret) {
+ msg->status = ret;
+ bfin_spi_giveback(drv_data);
+ }
+
+ bfin_write(&drv_data->regs->status, 0xFFFFFFFF);
+ bfin_spi_cs_active(drv_data, chip);
+ drv_data->state = RUNNING_STATE;
+
+ if (chip->enable_dma)
+ ret = bfin_spi_dma_xfer(drv_data);
+ else
+ ret = bfin_spi_pio_xfer(drv_data);
+ if (ret) {
+ msg->status = ret;
+ bfin_spi_giveback(drv_data);
+ }
+}
+
+static int bfin_spi_transfer_one_message(struct spi_master *master,
+ struct spi_message *m)
+{
+ struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
+
+ drv_data->cur_msg = m;
+ drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
+ bfin_spi_restore_state(drv_data);
+
+ drv_data->state = START_STATE;
+ drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
+ struct spi_transfer, transfer_list);
+
+ tasklet_schedule(&drv_data->pump_transfers);
+ return 0;
+}
+
+#define MAX_SPI_SSEL 7
+
+static const u16 ssel[][MAX_SPI_SSEL] = {
+ {P_SPI0_SSEL1, P_SPI0_SSEL2, P_SPI0_SSEL3,
+ P_SPI0_SSEL4, P_SPI0_SSEL5,
+ P_SPI0_SSEL6, P_SPI0_SSEL7},
+
+ {P_SPI1_SSEL1, P_SPI1_SSEL2, P_SPI1_SSEL3,
+ P_SPI1_SSEL4, P_SPI1_SSEL5,
+ P_SPI1_SSEL6, P_SPI1_SSEL7},
+
+ {P_SPI2_SSEL1, P_SPI2_SSEL2, P_SPI2_SSEL3,
+ P_SPI2_SSEL4, P_SPI2_SSEL5,
+ P_SPI2_SSEL6, P_SPI2_SSEL7},
+};
+
+static int bfin_spi_setup(struct spi_device *spi)
+{
+ struct bfin_spi_master *drv_data = spi_master_get_devdata(spi->master);
+ struct bfin_spi_device *chip = spi_get_ctldata(spi);
+ u32 bfin_ctl_reg = SPI_CTL_ODM | SPI_CTL_PSSE;
+ int ret = -EINVAL;
+
+ if (!chip) {
+ struct bfin_spi3_chip *chip_info = spi->controller_data;
+
+ chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+ if (!chip) {
+ dev_err(&spi->dev, "can not allocate chip data\n");
+ return -ENOMEM;
+ }
+ if (chip_info) {
+ if (chip_info->control & ~bfin_ctl_reg) {
+ dev_err(&spi->dev,
+ "do not set bits that the SPI framework manages\n");
+ goto error;
+ }
+ chip->control = chip_info->control;
+ chip->cs_chg_udelay = chip_info->cs_chg_udelay;
+ chip->tx_dummy_val = chip_info->tx_dummy_val;
+ chip->enable_dma = chip_info->enable_dma;
+ }
+ chip->cs = spi->chip_select;
+ if (chip->cs < MAX_CTRL_CS) {
+ chip->ssel = (1 << chip->cs) << 8;
+ ret = peripheral_request(ssel[spi->master->bus_num]
+ [chip->cs-1], dev_name(&spi->dev));
+ if (ret) {
+ dev_err(&spi->dev, "peripheral_request() error\n");
+ goto error;
+ }
+ } else {
+ chip->cs_gpio = chip->cs - MAX_CTRL_CS;
+ ret = gpio_request_one(chip->cs_gpio, GPIOF_OUT_INIT_HIGH,
+ dev_name(&spi->dev));
+ if (ret) {
+ dev_err(&spi->dev, "gpio_request_one() error\n");
+ goto error;
+ }
+ }
+ spi_set_ctldata(spi, chip);
+ }
+
+ /* force a default base state */
+ chip->control &= bfin_ctl_reg;
+
+ if (spi->mode & SPI_CPOL)
+ chip->control |= SPI_CTL_CPOL;
+ if (spi->mode & SPI_CPHA)
+ chip->control |= SPI_CTL_CPHA;
+ if (spi->mode & SPI_LSB_FIRST)
+ chip->control |= SPI_CTL_LSBF;
+ chip->control |= SPI_CTL_MSTR;
+ /* we choose software to controll cs */
+ chip->control &= ~SPI_CTL_ASSEL;
+
+ chip->clock = hz_to_spi_clock(drv_data->sclk, spi->max_speed_hz);
+
+ bfin_spi_cs_enable(drv_data, chip);
+ bfin_spi_cs_deactive(drv_data, chip);
+
+ return 0;
+error:
+ if (chip) {
+ kfree(chip);
+ spi_set_ctldata(spi, NULL);
+ }
+
+ return ret;
+}
+
+static void bfin_spi_cleanup(struct spi_device *spi)
+{
+ struct bfin_spi_device *chip = spi_get_ctldata(spi);
+ struct bfin_spi_master *drv_data = spi_master_get_devdata(spi->master);
+
+ if (!chip)
+ return;
+
+ if (chip->cs < MAX_CTRL_CS) {
+ peripheral_free(ssel[spi->master->bus_num]
+ [chip->cs-1]);
+ bfin_spi_cs_disable(drv_data, chip);
+ } else {
+ gpio_free(chip->cs_gpio);
+ }
+
+ kfree(chip);
+ spi_set_ctldata(spi, NULL);
+}
+
+static irqreturn_t bfin_spi_tx_dma_isr(int irq, void *dev_id)
+{
+ struct bfin_spi_master *drv_data = dev_id;
+ u32 dma_stat = get_dma_curr_irqstat(drv_data->tx_dma);
+
+ clear_dma_irqstat(drv_data->tx_dma);
+ if (dma_stat & DMA_DONE) {
+ drv_data->tx_num++;
+ } else {
+ dev_err(&drv_data->master->dev,
+ "spi tx dma error: %d\n", dma_stat);
+ if (drv_data->tx)
+ drv_data->state = ERROR_STATE;
+ }
+ bfin_write_and(&drv_data->regs->tx_control, ~SPI_TXCTL_TDR_NF);
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t bfin_spi_rx_dma_isr(int irq, void *dev_id)
+{
+ struct bfin_spi_master *drv_data = dev_id;
+ struct spi_message *msg = drv_data->cur_msg;
+ u32 dma_stat = get_dma_curr_irqstat(drv_data->rx_dma);
+
+ clear_dma_irqstat(drv_data->rx_dma);
+ if (dma_stat & DMA_DONE) {
+ drv_data->rx_num++;
+ /* we may fail on tx dma */
+ if (drv_data->state != ERROR_STATE)
+ msg->actual_length += drv_data->transfer_len;
+ } else {
+ drv_data->state = ERROR_STATE;
+ dev_err(&drv_data->master->dev,
+ "spi rx dma error: %d\n", dma_stat);
+ }
+ bfin_write(&drv_data->regs->tx_control, 0);
+ bfin_write(&drv_data->regs->rx_control, 0);
+ if (drv_data->rx_num != drv_data->tx_num)
+ dev_dbg(&drv_data->master->dev,
+ "dma interrupt missing: tx=%d,rx=%d\n",
+ drv_data->tx_num, drv_data->rx_num);
+ tasklet_schedule(&drv_data->pump_transfers);
+ return IRQ_HANDLED;
+}
+
+static int bfin_spi_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct bfin_spi3_master *info = dev->platform_data;
+ struct spi_master *master;
+ struct bfin_spi_master *drv_data;
+ struct resource *mem, *res;
+ unsigned int tx_dma, rx_dma;
+ unsigned long sclk;
+ int ret;
+
+ if (!info) {
+ dev_err(dev, "platform data missing!\n");
+ return -ENODEV;
+ }
+
+ sclk = get_sclk1();
+ if (!sclk) {
+ dev_err(dev, "can not get sclk1\n");
+ return -ENXIO;
+ }
+
+ /* get register base and tx/rx dma */
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!mem) {
+ dev_err(dev, "can not get register base\n");
+ return -ENXIO;
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
+ if (!res) {
+ dev_err(dev, "can not get tx dma resource\n");
+ return -ENXIO;
+ }
+ tx_dma = res->start;
+
+ res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
+ if (!res) {
+ dev_err(dev, "can not get rx dma resource\n");
+ return -ENXIO;
+ }
+ rx_dma = res->start;
+
+ /* allocate master with space for drv_data */
+ master = spi_alloc_master(dev, sizeof(*drv_data));
+ if (!master) {
+ dev_err(dev, "can not alloc spi_master\n");
+ return -ENOMEM;
+ }
+ platform_set_drvdata(pdev, master);
+
+ /* the mode bits supported by this driver */
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+
+ master->bus_num = pdev->id;
+ master->num_chipselect = info->num_chipselect;
+ master->cleanup = bfin_spi_cleanup;
+ master->setup = bfin_spi_setup;
+ master->transfer_one_message = bfin_spi_transfer_one_message;
+ master->bits_per_word_mask = BIT(32 - 1) | BIT(16 - 1) | BIT(8 - 1);
+
+ drv_data = spi_master_get_devdata(master);
+ drv_data->master = master;
+ drv_data->tx_dma = tx_dma;
+ drv_data->rx_dma = rx_dma;
+ drv_data->pin_req = info->pin_req;
+ drv_data->sclk = sclk;
+
+ drv_data->regs = devm_ioremap_resource(dev, mem);
+ if (IS_ERR(drv_data->regs)) {
+ ret = PTR_ERR(drv_data->regs);
+ goto err_put_master;
+ }
+
+ /* request tx and rx dma */
+ ret = request_dma(tx_dma, "SPI_TX_DMA");
+ if (ret) {
+ dev_err(dev, "can not request SPI TX DMA channel\n");
+ goto err_put_master;
+ }
+ set_dma_callback(tx_dma, bfin_spi_tx_dma_isr, drv_data);
+
+ ret = request_dma(rx_dma, "SPI_RX_DMA");
+ if (ret) {
+ dev_err(dev, "can not request SPI RX DMA channel\n");
+ goto err_free_tx_dma;
+ }
+ set_dma_callback(drv_data->rx_dma, bfin_spi_rx_dma_isr, drv_data);
+
+ /* request CLK, MOSI and MISO */
+ ret = peripheral_request_list(drv_data->pin_req, "bfin-spi3");
+ if (ret < 0) {
+ dev_err(dev, "can not request spi pins\n");
+ goto err_free_rx_dma;
+ }
+
+ bfin_write(&drv_data->regs->control, SPI_CTL_MSTR | SPI_CTL_CPHA);
+ bfin_write(&drv_data->regs->ssel, 0x0000FE00);
+ bfin_write(&drv_data->regs->delay, 0x0);
+
+ tasklet_init(&drv_data->pump_transfers,
+ bfin_spi_pump_transfers, (unsigned long)drv_data);
+ /* register with the SPI framework */
+ ret = spi_register_master(master);
+ if (ret) {
+ dev_err(dev, "can not register spi master\n");
+ goto err_free_peripheral;
+ }
+
+ return ret;
+
+err_free_peripheral:
+ peripheral_free_list(drv_data->pin_req);
+err_free_rx_dma:
+ free_dma(rx_dma);
+err_free_tx_dma:
+ free_dma(tx_dma);
+err_put_master:
+ platform_set_drvdata(pdev, NULL);
+ spi_master_put(master);
+
+ return ret;
+}
+
+static int bfin_spi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master = platform_get_drvdata(pdev);
+ struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
+
+ bfin_spi_disable(drv_data);
+
+ peripheral_free_list(drv_data->pin_req);
+ free_dma(drv_data->rx_dma);
+ free_dma(drv_data->tx_dma);
+
+ platform_set_drvdata(pdev, NULL);
+ spi_unregister_master(drv_data->master);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int bfin_spi_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
+
+ spi_master_suspend(master);
+
+ drv_data->control = bfin_read(&drv_data->regs->control);
+ drv_data->ssel = bfin_read(&drv_data->regs->ssel);
+
+ bfin_write(&drv_data->regs->control, SPI_CTL_MSTR | SPI_CTL_CPHA);
+ bfin_write(&drv_data->regs->ssel, 0x0000FE00);
+ dma_disable_irq(drv_data->rx_dma);
+ dma_disable_irq(drv_data->tx_dma);
+
+ return 0;
+}
+
+static int bfin_spi_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct bfin_spi_master *drv_data = spi_master_get_devdata(master);
+ int ret = 0;
+
+ /* bootrom may modify spi and dma status when resume in spi boot mode */
+ disable_dma(drv_data->rx_dma);
+
+ dma_enable_irq(drv_data->rx_dma);
+ dma_enable_irq(drv_data->tx_dma);
+ bfin_write(&drv_data->regs->control, drv_data->control);
+ bfin_write(&drv_data->regs->ssel, drv_data->ssel);
+
+ ret = spi_master_resume(master);
+ if (ret) {
+ free_dma(drv_data->rx_dma);
+ free_dma(drv_data->tx_dma);
+ }
+
+ return ret;
+}
+#endif
+static const struct dev_pm_ops bfin_spi_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(bfin_spi_suspend, bfin_spi_resume)
+};
+
+MODULE_ALIAS("platform:bfin-spi3");
+static struct platform_driver bfin_spi_driver = {
+ .driver = {
+ .name = "bfin-spi3",
+ .owner = THIS_MODULE,
+ .pm = &bfin_spi_pm_ops,
+ },
+ .remove = bfin_spi_remove,
+};
+
+module_platform_driver_probe(bfin_spi_driver, bfin_spi_probe);
+
+MODULE_DESCRIPTION("Analog Devices SPI3 controller driver");
+MODULE_AUTHOR("Scott Jiang <Scott.Jiang.Linux@gmail.com>");
+MODULE_LICENSE("GPL v2");
projects / GitHub / LineageOS / android_kernel_motorola_exynos9610.git / commitdiff