#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/init.h>
+#include <linux/mutex.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/hardware.h>
#define PXA_SSP_PORTS 3
+#define TIMEOUT 100000
+
struct ssp_info_ {
int irq;
u32 clock;
#endif
};
-static DECLARE_MUTEX(sem);
+static DEFINE_MUTEX(mutex);
static int use_count[PXA_SSP_PORTS] = {0, 0, 0};
-static irqreturn_t ssp_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+static irqreturn_t ssp_interrupt(int irq, void *dev_id)
{
struct ssp_dev *dev = (struct ssp_dev*) dev_id;
unsigned int status = SSSR_P(dev->port);
* The caller is expected to perform the necessary locking.
*
* Returns:
- * %-ETIMEDOUT timeout occurred (for future)
+ * %-ETIMEDOUT timeout occurred
* 0 success
*/
int ssp_write_word(struct ssp_dev *dev, u32 data)
{
- while (!(SSSR_P(dev->port) & SSSR_TNF))
+ int timeout = TIMEOUT;
+
+ while (!(SSSR_P(dev->port) & SSSR_TNF)) {
+ if (!--timeout)
+ return -ETIMEDOUT;
cpu_relax();
+ }
SSDR_P(dev->port) = data;
* The caller is expected to perform the necessary locking.
*
* Returns:
- * %-ETIMEDOUT timeout occurred (for future)
+ * %-ETIMEDOUT timeout occurred
* 32-bit data success
*/
-int ssp_read_word(struct ssp_dev *dev)
+int ssp_read_word(struct ssp_dev *dev, u32 *data)
{
- while (!(SSSR_P(dev->port) & SSSR_RNE))
+ int timeout = TIMEOUT;
+
+ while (!(SSSR_P(dev->port) & SSSR_RNE)) {
+ if (!--timeout)
+ return -ETIMEDOUT;
cpu_relax();
+ }
- return SSDR_P(dev->port);
+ *data = SSDR_P(dev->port);
+ return 0;
}
/**
*
* The caller is expected to perform the necessary locking.
*/
-void ssp_flush(struct ssp_dev *dev)
+int ssp_flush(struct ssp_dev *dev)
{
+ int timeout = TIMEOUT * 2;
+
do {
while (SSSR_P(dev->port) & SSSR_RNE) {
+ if (!--timeout)
+ return -ETIMEDOUT;
(void) SSDR_P(dev->port);
}
+ if (!--timeout)
+ return -ETIMEDOUT;
} while (SSSR_P(dev->port) & SSSR_BSY);
+
+ return 0;
}
/**
if (port > PXA_SSP_PORTS || port == 0)
return -ENODEV;
- down(&sem);
+ mutex_lock(&mutex);
if (use_count[port - 1]) {
- up(&sem);
+ mutex_unlock(&mutex);
return -EBUSY;
}
use_count[port - 1]++;
if (!request_mem_region(__PREG(SSCR0_P(port)), 0x2c, "SSP")) {
use_count[port - 1]--;
- up(&sem);
+ mutex_unlock(&mutex);
return -EBUSY;
}
dev->port = port;
/* turn on SSP port clock */
pxa_set_cken(ssp_info[port-1].clock, 1);
- up(&sem);
+ mutex_unlock(&mutex);
return 0;
out_region:
release_mem_region(__PREG(SSCR0_P(port)), 0x2c);
use_count[port - 1]--;
- up(&sem);
+ mutex_unlock(&mutex);
return ret;
}
*/
void ssp_exit(struct ssp_dev *dev)
{
- down(&sem);
+ mutex_lock(&mutex);
SSCR0_P(dev->port) &= ~SSCR0_SSE;
if (dev->port > PXA_SSP_PORTS || dev->port == 0) {
free_irq(dev->irq, dev);
release_mem_region(__PREG(SSCR0_P(dev->port)), 0x2c);
use_count[dev->port - 1]--;
- up(&sem);
+ mutex_unlock(&mutex);
}
EXPORT_SYMBOL(ssp_write_word);