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path: root/drivers/spi/mpc52xx_spi.c
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Diffstat (limited to 'drivers/spi/mpc52xx_spi.c')
-rw-r--r--drivers/spi/mpc52xx_spi.c86
1 files changed, 72 insertions, 14 deletions
diff --git a/drivers/spi/mpc52xx_spi.c b/drivers/spi/mpc52xx_spi.c
index ef8379b2c172..45bfe6458173 100644
--- a/drivers/spi/mpc52xx_spi.c
+++ b/drivers/spi/mpc52xx_spi.c
@@ -18,9 +18,9 @@
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/spi/spi.h>
-#include <linux/spi/mpc52xx_spi.h>
#include <linux/of_spi.h>
#include <linux/io.h>
+#include <linux/of_gpio.h>
#include <asm/time.h>
#include <asm/mpc52xx.h>
@@ -53,7 +53,7 @@ MODULE_LICENSE("GPL");
/* FSM state return values */
#define FSM_STOP 0 /* Nothing more for the state machine to */
/* do. If something interesting happens */
- /* then and IRQ will be received */
+ /* 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 */
@@ -61,13 +61,12 @@ MODULE_LICENSE("GPL");
/* Driver internal data */
struct mpc52xx_spi {
struct spi_master *master;
- u32 sysclk;
void __iomem *regs;
int irq0; /* MODF irq */
int irq1; /* SPIF irq */
- int ipb_freq;
+ unsigned int ipb_freq;
- /* Statistics */
+ /* Statistics; not used now, but will be reintroduced for debugfs */
int msg_count;
int wcol_count;
int wcol_ticks;
@@ -79,7 +78,6 @@ struct mpc52xx_spi {
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 */
@@ -89,6 +87,8 @@ struct mpc52xx_spi {
u8 *rx_buf;
const u8 *tx_buf;
int cs_change;
+ int gpio_cs_count;
+ unsigned int *gpio_cs;
};
/*
@@ -96,7 +96,13 @@ struct mpc52xx_spi {
*/
static void mpc52xx_spi_chipsel(struct mpc52xx_spi *ms, int value)
{
- out_8(ms->regs + SPI_PORTDATA, value ? 0 : 0x08);
+ 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);
}
/*
@@ -221,7 +227,7 @@ static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms,
ms->wcol_tx_timestamp = get_tbl();
data = 0;
if (ms->tx_buf)
- data = *(ms->tx_buf-1);
+ data = *(ms->tx_buf - 1);
out_8(ms->regs + SPI_DATA, data); /* try again */
return FSM_CONTINUE;
} else if (status & SPI_STATUS_MODF) {
@@ -390,7 +396,9 @@ static int __devinit mpc52xx_spi_probe(struct of_device *op,
struct spi_master *master;
struct mpc52xx_spi *ms;
void __iomem *regs;
- int rc;
+ u8 ctrl1;
+ int rc, i = 0;
+ int gpio_cs;
/* MMIO registers */
dev_dbg(&op->dev, "probing mpc5200 SPI device\n");
@@ -399,7 +407,8 @@ static int __devinit mpc52xx_spi_probe(struct of_device *op,
return -ENODEV;
/* initialize the device */
- out_8(regs+SPI_CTRL1, SPI_CTRL1_SPIE | SPI_CTRL1_SPE | SPI_CTRL1_MSTR);
+ 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 */
@@ -409,6 +418,8 @@ static int __devinit mpc52xx_spi_probe(struct of_device *op,
* 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");
@@ -422,10 +433,12 @@ static int __devinit mpc52xx_spi_probe(struct of_device *op,
rc = -ENOMEM;
goto err_alloc;
}
+
master->bus_num = -1;
- master->num_chipselect = 1;
master->setup = mpc52xx_spi_setup;
master->transfer = mpc52xx_spi_transfer;
+ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+
dev_set_drvdata(&op->dev, master);
ms = spi_master_get_devdata(master);
@@ -435,16 +448,51 @@ static int __devinit mpc52xx_spi_probe(struct of_device *op,
ms->irq1 = irq_of_parse_and_map(op->node, 1);
ms->state = mpc52xx_spi_fsmstate_idle;
ms->ipb_freq = mpc5xxx_get_bus_frequency(op->node);
+ ms->gpio_cs_count = of_gpio_count(op->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->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, IRQF_SAMPLE_RANDOM,
+ rc = request_irq(ms->irq0, mpc52xx_spi_irq, 0,
"mpc5200-spi-modf", ms);
- rc |= request_irq(ms->irq1, mpc52xx_spi_irq, IRQF_SAMPLE_RANDOM,
- "mpc5200-spi-spiF", 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);
@@ -471,6 +519,11 @@ static int __devinit mpc52xx_spi_probe(struct of_device *op,
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);
@@ -481,10 +534,15 @@ static int __devexit mpc52xx_spi_remove(struct of_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);
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