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authorGrant Likely <grant.likely@secretlab.ca>2011-06-06 01:16:30 -0600
committerGrant Likely <grant.likely@secretlab.ca>2011-06-06 01:16:30 -0600
commitca632f556697d45d67ed5cada7cedf3ddfe0db4b (patch)
treef393534b929abb32813ea5c495f1ac6d93a10d1d /drivers/spi/mpc52xx_spi.c
parentspi/bitbang: initialize bits_per_word as specified by spi message (diff)
downloadlinux-dev-ca632f556697d45d67ed5cada7cedf3ddfe0db4b.tar.xz
linux-dev-ca632f556697d45d67ed5cada7cedf3ddfe0db4b.zip
spi: reorganize drivers
Sort the SPI makefile and enforce the naming convention spi_*.c for spi drivers. This change also rolls the contents of atmel_spi.h into the .c file since there is only one user of that particular include file. v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be be the predominant pattern for subsystem prefixes. - Clean up filenames in Kconfig and header comment blocks Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/spi/mpc52xx_spi.c')
-rw-r--r--drivers/spi/mpc52xx_spi.c579
1 files changed, 0 insertions, 579 deletions
diff --git a/drivers/spi/mpc52xx_spi.c b/drivers/spi/mpc52xx_spi.c
deleted file mode 100644
index 015a974bed72..000000000000
--- a/drivers/spi/mpc52xx_spi.c
+++ /dev/null
@@ -1,579 +0,0 @@
-/*
- * MPC52xx SPI bus driver.
- *
- * Copyright (C) 2008 Secret Lab Technologies Ltd.
- *
- * This file is released under the GPLv2
- *
- * This is the driver for the MPC5200's dedicated SPI controller.
- *
- * Note: this driver does not support the MPC5200 PSC in SPI mode. For
- * that driver see drivers/spi/mpc52xx_psc_spi.c
- */
-
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/errno.h>
-#include <linux/of_platform.h>
-#include <linux/interrupt.h>
-#include <linux/delay.h>
-#include <linux/spi/spi.h>
-#include <linux/io.h>
-#include <linux/of_gpio.h>
-#include <linux/slab.h>
-#include <asm/time.h>
-#include <asm/mpc52xx.h>
-
-MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
-MODULE_DESCRIPTION("MPC52xx SPI (non-PSC) Driver");
-MODULE_LICENSE("GPL");
-
-/* Register offsets */
-#define SPI_CTRL1 0x00
-#define SPI_CTRL1_SPIE (1 << 7)
-#define SPI_CTRL1_SPE (1 << 6)
-#define SPI_CTRL1_MSTR (1 << 4)
-#define SPI_CTRL1_CPOL (1 << 3)
-#define SPI_CTRL1_CPHA (1 << 2)
-#define SPI_CTRL1_SSOE (1 << 1)
-#define SPI_CTRL1_LSBFE (1 << 0)
-
-#define SPI_CTRL2 0x01
-#define SPI_BRR 0x04
-
-#define SPI_STATUS 0x05
-#define SPI_STATUS_SPIF (1 << 7)
-#define SPI_STATUS_WCOL (1 << 6)
-#define SPI_STATUS_MODF (1 << 4)
-
-#define SPI_DATA 0x09
-#define SPI_PORTDATA 0x0d
-#define SPI_DATADIR 0x10
-
-/* FSM state return values */
-#define FSM_STOP 0 /* Nothing more for the state machine to */
- /* do. If something interesting happens */
- /* then an IRQ will be received */
-#define FSM_POLL 1 /* need to poll for completion, an IRQ is */
- /* not expected */
-#define FSM_CONTINUE 2 /* Keep iterating the state machine */
-
-/* Driver internal data */
-struct mpc52xx_spi {
- struct spi_master *master;
- void __iomem *regs;
- int irq0; /* MODF irq */
- int irq1; /* SPIF irq */
- unsigned int ipb_freq;
-
- /* Statistics; not used now, but will be reintroduced for debugfs */
- int msg_count;
- int wcol_count;
- int wcol_ticks;
- u32 wcol_tx_timestamp;
- int modf_count;
- int byte_count;
-
- struct list_head queue; /* queue of pending messages */
- spinlock_t lock;
- struct work_struct work;
-
- /* Details of current transfer (length, and buffer pointers) */
- struct spi_message *message; /* current message */
- struct spi_transfer *transfer; /* current transfer */
- int (*state)(int irq, struct mpc52xx_spi *ms, u8 status, u8 data);
- int len;
- int timestamp;
- u8 *rx_buf;
- const u8 *tx_buf;
- int cs_change;
- int gpio_cs_count;
- unsigned int *gpio_cs;
-};
-
-/*
- * CS control function
- */
-static void mpc52xx_spi_chipsel(struct mpc52xx_spi *ms, int value)
-{
- int cs;
-
- if (ms->gpio_cs_count > 0) {
- cs = ms->message->spi->chip_select;
- gpio_set_value(ms->gpio_cs[cs], value ? 0 : 1);
- } else
- out_8(ms->regs + SPI_PORTDATA, value ? 0 : 0x08);
-}
-
-/*
- * Start a new transfer. This is called both by the idle state
- * for the first transfer in a message, and by the wait state when the
- * previous transfer in a message is complete.
- */
-static void mpc52xx_spi_start_transfer(struct mpc52xx_spi *ms)
-{
- ms->rx_buf = ms->transfer->rx_buf;
- ms->tx_buf = ms->transfer->tx_buf;
- ms->len = ms->transfer->len;
-
- /* Activate the chip select */
- if (ms->cs_change)
- mpc52xx_spi_chipsel(ms, 1);
- ms->cs_change = ms->transfer->cs_change;
-
- /* Write out the first byte */
- ms->wcol_tx_timestamp = get_tbl();
- if (ms->tx_buf)
- out_8(ms->regs + SPI_DATA, *ms->tx_buf++);
- else
- out_8(ms->regs + SPI_DATA, 0);
-}
-
-/* Forward declaration of state handlers */
-static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms,
- u8 status, u8 data);
-static int mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms,
- u8 status, u8 data);
-
-/*
- * IDLE state
- *
- * No transfers are in progress; if another transfer is pending then retrieve
- * it and kick it off. Otherwise, stop processing the state machine
- */
-static int
-mpc52xx_spi_fsmstate_idle(int irq, struct mpc52xx_spi *ms, u8 status, u8 data)
-{
- struct spi_device *spi;
- int spr, sppr;
- u8 ctrl1;
-
- if (status && (irq != NO_IRQ))
- dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n",
- status);
-
- /* Check if there is another transfer waiting. */
- if (list_empty(&ms->queue))
- return FSM_STOP;
-
- /* get the head of the queue */
- ms->message = list_first_entry(&ms->queue, struct spi_message, queue);
- list_del_init(&ms->message->queue);
-
- /* Setup the controller parameters */
- ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR;
- spi = ms->message->spi;
- if (spi->mode & SPI_CPHA)
- ctrl1 |= SPI_CTRL1_CPHA;
- if (spi->mode & SPI_CPOL)
- ctrl1 |= SPI_CTRL1_CPOL;
- if (spi->mode & SPI_LSB_FIRST)
- ctrl1 |= SPI_CTRL1_LSBFE;
- out_8(ms->regs + SPI_CTRL1, ctrl1);
-
- /* Setup the controller speed */
- /* minimum divider is '2'. Also, add '1' to force rounding the
- * divider up. */
- sppr = ((ms->ipb_freq / ms->message->spi->max_speed_hz) + 1) >> 1;
- spr = 0;
- if (sppr < 1)
- sppr = 1;
- while (((sppr - 1) & ~0x7) != 0) {
- sppr = (sppr + 1) >> 1; /* add '1' to force rounding up */
- spr++;
- }
- sppr--; /* sppr quantity in register is offset by 1 */
- if (spr > 7) {
- /* Don't overrun limits of SPI baudrate register */
- spr = 7;
- sppr = 7;
- }
- out_8(ms->regs + SPI_BRR, sppr << 4 | spr); /* Set speed */
-
- ms->cs_change = 1;
- ms->transfer = container_of(ms->message->transfers.next,
- struct spi_transfer, transfer_list);
-
- mpc52xx_spi_start_transfer(ms);
- ms->state = mpc52xx_spi_fsmstate_transfer;
-
- return FSM_CONTINUE;
-}
-
-/*
- * TRANSFER state
- *
- * In the middle of a transfer. If the SPI core has completed processing
- * a byte, then read out the received data and write out the next byte
- * (unless this transfer is finished; in which case go on to the wait
- * state)
- */
-static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms,
- u8 status, u8 data)
-{
- if (!status)
- return ms->irq0 ? FSM_STOP : FSM_POLL;
-
- if (status & SPI_STATUS_WCOL) {
- /* The SPI controller is stoopid. At slower speeds, it may
- * raise the SPIF flag before the state machine is actually
- * finished, which causes a collision (internal to the state
- * machine only). The manual recommends inserting a delay
- * between receiving the interrupt and sending the next byte,
- * but it can also be worked around simply by retrying the
- * transfer which is what we do here. */
- ms->wcol_count++;
- ms->wcol_ticks += get_tbl() - ms->wcol_tx_timestamp;
- ms->wcol_tx_timestamp = get_tbl();
- data = 0;
- if (ms->tx_buf)
- data = *(ms->tx_buf - 1);
- out_8(ms->regs + SPI_DATA, data); /* try again */
- return FSM_CONTINUE;
- } else if (status & SPI_STATUS_MODF) {
- ms->modf_count++;
- dev_err(&ms->master->dev, "mode fault\n");
- mpc52xx_spi_chipsel(ms, 0);
- ms->message->status = -EIO;
- ms->message->complete(ms->message->context);
- ms->state = mpc52xx_spi_fsmstate_idle;
- return FSM_CONTINUE;
- }
-
- /* Read data out of the spi device */
- ms->byte_count++;
- if (ms->rx_buf)
- *ms->rx_buf++ = data;
-
- /* Is the transfer complete? */
- ms->len--;
- if (ms->len == 0) {
- ms->timestamp = get_tbl();
- ms->timestamp += ms->transfer->delay_usecs * tb_ticks_per_usec;
- ms->state = mpc52xx_spi_fsmstate_wait;
- return FSM_CONTINUE;
- }
-
- /* Write out the next byte */
- ms->wcol_tx_timestamp = get_tbl();
- if (ms->tx_buf)
- out_8(ms->regs + SPI_DATA, *ms->tx_buf++);
- else
- out_8(ms->regs + SPI_DATA, 0);
-
- return FSM_CONTINUE;
-}
-
-/*
- * WAIT state
- *
- * A transfer has completed; need to wait for the delay period to complete
- * before starting the next transfer
- */
-static int
-mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, u8 status, u8 data)
-{
- if (status && irq)
- dev_err(&ms->master->dev, "spurious irq, status=0x%.2x\n",
- status);
-
- if (((int)get_tbl()) - ms->timestamp < 0)
- return FSM_POLL;
-
- ms->message->actual_length += ms->transfer->len;
-
- /* Check if there is another transfer in this message. If there
- * aren't then deactivate CS, notify sender, and drop back to idle
- * to start the next message. */
- if (ms->transfer->transfer_list.next == &ms->message->transfers) {
- ms->msg_count++;
- mpc52xx_spi_chipsel(ms, 0);
- ms->message->status = 0;
- ms->message->complete(ms->message->context);
- ms->state = mpc52xx_spi_fsmstate_idle;
- return FSM_CONTINUE;
- }
-
- /* There is another transfer; kick it off */
-
- if (ms->cs_change)
- mpc52xx_spi_chipsel(ms, 0);
-
- ms->transfer = container_of(ms->transfer->transfer_list.next,
- struct spi_transfer, transfer_list);
- mpc52xx_spi_start_transfer(ms);
- ms->state = mpc52xx_spi_fsmstate_transfer;
- return FSM_CONTINUE;
-}
-
-/**
- * mpc52xx_spi_fsm_process - Finite State Machine iteration function
- * @irq: irq number that triggered the FSM or 0 for polling
- * @ms: pointer to mpc52xx_spi driver data
- */
-static void mpc52xx_spi_fsm_process(int irq, struct mpc52xx_spi *ms)
-{
- int rc = FSM_CONTINUE;
- u8 status, data;
-
- while (rc == FSM_CONTINUE) {
- /* Interrupt cleared by read of STATUS followed by
- * read of DATA registers */
- status = in_8(ms->regs + SPI_STATUS);
- data = in_8(ms->regs + SPI_DATA);
- rc = ms->state(irq, ms, status, data);
- }
-
- if (rc == FSM_POLL)
- schedule_work(&ms->work);
-}
-
-/**
- * mpc52xx_spi_irq - IRQ handler
- */
-static irqreturn_t mpc52xx_spi_irq(int irq, void *_ms)
-{
- struct mpc52xx_spi *ms = _ms;
- spin_lock(&ms->lock);
- mpc52xx_spi_fsm_process(irq, ms);
- spin_unlock(&ms->lock);
- return IRQ_HANDLED;
-}
-
-/**
- * mpc52xx_spi_wq - Workqueue function for polling the state machine
- */
-static void mpc52xx_spi_wq(struct work_struct *work)
-{
- struct mpc52xx_spi *ms = container_of(work, struct mpc52xx_spi, work);
- unsigned long flags;
-
- spin_lock_irqsave(&ms->lock, flags);
- mpc52xx_spi_fsm_process(0, ms);
- spin_unlock_irqrestore(&ms->lock, flags);
-}
-
-/*
- * spi_master ops
- */
-
-static int mpc52xx_spi_setup(struct spi_device *spi)
-{
- if (spi->bits_per_word % 8)
- return -EINVAL;
-
- if (spi->mode & ~(SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST))
- return -EINVAL;
-
- if (spi->chip_select >= spi->master->num_chipselect)
- return -EINVAL;
-
- return 0;
-}
-
-static int mpc52xx_spi_transfer(struct spi_device *spi, struct spi_message *m)
-{
- struct mpc52xx_spi *ms = spi_master_get_devdata(spi->master);
- unsigned long flags;
-
- m->actual_length = 0;
- m->status = -EINPROGRESS;
-
- spin_lock_irqsave(&ms->lock, flags);
- list_add_tail(&m->queue, &ms->queue);
- spin_unlock_irqrestore(&ms->lock, flags);
- schedule_work(&ms->work);
-
- return 0;
-}
-
-/*
- * OF Platform Bus Binding
- */
-static int __devinit mpc52xx_spi_probe(struct platform_device *op)
-{
- struct spi_master *master;
- struct mpc52xx_spi *ms;
- void __iomem *regs;
- u8 ctrl1;
- int rc, i = 0;
- int gpio_cs;
-
- /* MMIO registers */
- dev_dbg(&op->dev, "probing mpc5200 SPI device\n");
- regs = of_iomap(op->dev.of_node, 0);
- if (!regs)
- return -ENODEV;
-
- /* initialize the device */
- ctrl1 = SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR;
- out_8(regs + SPI_CTRL1, ctrl1);
- out_8(regs + SPI_CTRL2, 0x0);
- out_8(regs + SPI_DATADIR, 0xe); /* Set output pins */
- out_8(regs + SPI_PORTDATA, 0x8); /* Deassert /SS signal */
-
- /* Clear the status register and re-read it to check for a MODF
- * failure. This driver cannot currently handle multiple masters
- * on the SPI bus. This fault will also occur if the SPI signals
- * are not connected to any pins (port_config setting) */
- in_8(regs + SPI_STATUS);
- out_8(regs + SPI_CTRL1, ctrl1);
-
- in_8(regs + SPI_DATA);
- if (in_8(regs + SPI_STATUS) & SPI_STATUS_MODF) {
- dev_err(&op->dev, "mode fault; is port_config correct?\n");
- rc = -EIO;
- goto err_init;
- }
-
- dev_dbg(&op->dev, "allocating spi_master struct\n");
- master = spi_alloc_master(&op->dev, sizeof *ms);
- if (!master) {
- rc = -ENOMEM;
- goto err_alloc;
- }
-
- master->bus_num = -1;
- master->setup = mpc52xx_spi_setup;
- master->transfer = mpc52xx_spi_transfer;
- master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
- master->dev.of_node = op->dev.of_node;
-
- dev_set_drvdata(&op->dev, master);
-
- ms = spi_master_get_devdata(master);
- ms->master = master;
- ms->regs = regs;
- ms->irq0 = irq_of_parse_and_map(op->dev.of_node, 0);
- ms->irq1 = irq_of_parse_and_map(op->dev.of_node, 1);
- ms->state = mpc52xx_spi_fsmstate_idle;
- ms->ipb_freq = mpc5xxx_get_bus_frequency(op->dev.of_node);
- ms->gpio_cs_count = of_gpio_count(op->dev.of_node);
- if (ms->gpio_cs_count > 0) {
- master->num_chipselect = ms->gpio_cs_count;
- ms->gpio_cs = kmalloc(ms->gpio_cs_count * sizeof(unsigned int),
- GFP_KERNEL);
- if (!ms->gpio_cs) {
- rc = -ENOMEM;
- goto err_alloc;
- }
-
- for (i = 0; i < ms->gpio_cs_count; i++) {
- gpio_cs = of_get_gpio(op->dev.of_node, i);
- if (gpio_cs < 0) {
- dev_err(&op->dev,
- "could not parse the gpio field "
- "in oftree\n");
- rc = -ENODEV;
- goto err_gpio;
- }
-
- rc = gpio_request(gpio_cs, dev_name(&op->dev));
- if (rc) {
- dev_err(&op->dev,
- "can't request spi cs gpio #%d "
- "on gpio line %d\n", i, gpio_cs);
- goto err_gpio;
- }
-
- gpio_direction_output(gpio_cs, 1);
- ms->gpio_cs[i] = gpio_cs;
- }
- } else {
- master->num_chipselect = 1;
- }
-
- spin_lock_init(&ms->lock);
- INIT_LIST_HEAD(&ms->queue);
- INIT_WORK(&ms->work, mpc52xx_spi_wq);
-
- /* Decide if interrupts can be used */
- if (ms->irq0 && ms->irq1) {
- rc = request_irq(ms->irq0, mpc52xx_spi_irq, 0,
- "mpc5200-spi-modf", ms);
- rc |= request_irq(ms->irq1, mpc52xx_spi_irq, 0,
- "mpc5200-spi-spif", ms);
- if (rc) {
- free_irq(ms->irq0, ms);
- free_irq(ms->irq1, ms);
- ms->irq0 = ms->irq1 = 0;
- }
- } else {
- /* operate in polled mode */
- ms->irq0 = ms->irq1 = 0;
- }
-
- if (!ms->irq0)
- dev_info(&op->dev, "using polled mode\n");
-
- dev_dbg(&op->dev, "registering spi_master struct\n");
- rc = spi_register_master(master);
- if (rc)
- goto err_register;
-
- dev_info(&ms->master->dev, "registered MPC5200 SPI bus\n");
-
- return rc;
-
- err_register:
- dev_err(&ms->master->dev, "initialization failed\n");
- spi_master_put(master);
- err_gpio:
- while (i-- > 0)
- gpio_free(ms->gpio_cs[i]);
-
- kfree(ms->gpio_cs);
- err_alloc:
- err_init:
- iounmap(regs);
- return rc;
-}
-
-static int __devexit mpc52xx_spi_remove(struct platform_device *op)
-{
- struct spi_master *master = dev_get_drvdata(&op->dev);
- struct mpc52xx_spi *ms = spi_master_get_devdata(master);
- int i;
-
- free_irq(ms->irq0, ms);
- free_irq(ms->irq1, ms);
-
- for (i = 0; i < ms->gpio_cs_count; i++)
- gpio_free(ms->gpio_cs[i]);
-
- kfree(ms->gpio_cs);
- spi_unregister_master(master);
- spi_master_put(master);
- iounmap(ms->regs);
-
- return 0;
-}
-
-static const struct of_device_id mpc52xx_spi_match[] __devinitconst = {
- { .compatible = "fsl,mpc5200-spi", },
- {}
-};
-MODULE_DEVICE_TABLE(of, mpc52xx_spi_match);
-
-static struct platform_driver mpc52xx_spi_of_driver = {
- .driver = {
- .name = "mpc52xx-spi",
- .owner = THIS_MODULE,
- .of_match_table = mpc52xx_spi_match,
- },
- .probe = mpc52xx_spi_probe,
- .remove = __devexit_p(mpc52xx_spi_remove),
-};
-
-static int __init mpc52xx_spi_init(void)
-{
- return platform_driver_register(&mpc52xx_spi_of_driver);
-}
-module_init(mpc52xx_spi_init);
-
-static void __exit mpc52xx_spi_exit(void)
-{
- platform_driver_unregister(&mpc52xx_spi_of_driver);
-}
-module_exit(mpc52xx_spi_exit);
-