summaryrefslogtreecommitdiffstats
path: root/drivers/spi/spidev.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/spi/spidev.c')
-rw-r--r--drivers/spi/spidev.c125
1 files changed, 97 insertions, 28 deletions
diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index 6941e04afb8c..4eb7a980e670 100644
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -14,10 +14,6 @@
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/init.h>
@@ -317,6 +313,37 @@ done:
return status;
}
+static struct spi_ioc_transfer *
+spidev_get_ioc_message(unsigned int cmd, struct spi_ioc_transfer __user *u_ioc,
+ unsigned *n_ioc)
+{
+ struct spi_ioc_transfer *ioc;
+ u32 tmp;
+
+ /* Check type, command number and direction */
+ if (_IOC_TYPE(cmd) != SPI_IOC_MAGIC
+ || _IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0))
+ || _IOC_DIR(cmd) != _IOC_WRITE)
+ return ERR_PTR(-ENOTTY);
+
+ tmp = _IOC_SIZE(cmd);
+ if ((tmp % sizeof(struct spi_ioc_transfer)) != 0)
+ return ERR_PTR(-EINVAL);
+ *n_ioc = tmp / sizeof(struct spi_ioc_transfer);
+ if (*n_ioc == 0)
+ return NULL;
+
+ /* copy into scratch area */
+ ioc = kmalloc(tmp, GFP_KERNEL);
+ if (!ioc)
+ return ERR_PTR(-ENOMEM);
+ if (__copy_from_user(ioc, u_ioc, tmp)) {
+ kfree(ioc);
+ return ERR_PTR(-EFAULT);
+ }
+ return ioc;
+}
+
static long
spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
@@ -456,32 +483,15 @@ spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
default:
/* segmented and/or full-duplex I/O request */
- if (_IOC_NR(cmd) != _IOC_NR(SPI_IOC_MESSAGE(0))
- || _IOC_DIR(cmd) != _IOC_WRITE) {
- retval = -ENOTTY;
- break;
- }
-
- tmp = _IOC_SIZE(cmd);
- if ((tmp % sizeof(struct spi_ioc_transfer)) != 0) {
- retval = -EINVAL;
- break;
- }
- n_ioc = tmp / sizeof(struct spi_ioc_transfer);
- if (n_ioc == 0)
- break;
-
- /* copy into scratch area */
- ioc = kmalloc(tmp, GFP_KERNEL);
- if (!ioc) {
- retval = -ENOMEM;
- break;
- }
- if (__copy_from_user(ioc, (void __user *)arg, tmp)) {
- kfree(ioc);
- retval = -EFAULT;
+ /* Check message and copy into scratch area */
+ ioc = spidev_get_ioc_message(cmd,
+ (struct spi_ioc_transfer __user *)arg, &n_ioc);
+ if (IS_ERR(ioc)) {
+ retval = PTR_ERR(ioc);
break;
}
+ if (!ioc)
+ break; /* n_ioc is also 0 */
/* translate to spi_message, execute */
retval = spidev_message(spidev, ioc, n_ioc);
@@ -496,8 +506,67 @@ spidev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
#ifdef CONFIG_COMPAT
static long
+spidev_compat_ioc_message(struct file *filp, unsigned int cmd,
+ unsigned long arg)
+{
+ struct spi_ioc_transfer __user *u_ioc;
+ int retval = 0;
+ struct spidev_data *spidev;
+ struct spi_device *spi;
+ unsigned n_ioc, n;
+ struct spi_ioc_transfer *ioc;
+
+ u_ioc = (struct spi_ioc_transfer __user *) compat_ptr(arg);
+ if (!access_ok(VERIFY_READ, u_ioc, _IOC_SIZE(cmd)))
+ return -EFAULT;
+
+ /* guard against device removal before, or while,
+ * we issue this ioctl.
+ */
+ spidev = filp->private_data;
+ spin_lock_irq(&spidev->spi_lock);
+ spi = spi_dev_get(spidev->spi);
+ spin_unlock_irq(&spidev->spi_lock);
+
+ if (spi == NULL)
+ return -ESHUTDOWN;
+
+ /* SPI_IOC_MESSAGE needs the buffer locked "normally" */
+ mutex_lock(&spidev->buf_lock);
+
+ /* Check message and copy into scratch area */
+ ioc = spidev_get_ioc_message(cmd, u_ioc, &n_ioc);
+ if (IS_ERR(ioc)) {
+ retval = PTR_ERR(ioc);
+ goto done;
+ }
+ if (!ioc)
+ goto done; /* n_ioc is also 0 */
+
+ /* Convert buffer pointers */
+ for (n = 0; n < n_ioc; n++) {
+ ioc[n].rx_buf = (uintptr_t) compat_ptr(ioc[n].rx_buf);
+ ioc[n].tx_buf = (uintptr_t) compat_ptr(ioc[n].tx_buf);
+ }
+
+ /* translate to spi_message, execute */
+ retval = spidev_message(spidev, ioc, n_ioc);
+ kfree(ioc);
+
+done:
+ mutex_unlock(&spidev->buf_lock);
+ spi_dev_put(spi);
+ return retval;
+}
+
+static long
spidev_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
+ if (_IOC_TYPE(cmd) == SPI_IOC_MAGIC
+ && _IOC_NR(cmd) == _IOC_NR(SPI_IOC_MESSAGE(0))
+ && _IOC_DIR(cmd) == _IOC_WRITE)
+ return spidev_compat_ioc_message(filp, cmd, arg);
+
return spidev_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
}
#else