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authorLinus Torvalds <torvalds@linux-foundation.org>2015-02-09 13:36:20 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2015-02-09 13:36:20 -0800
commitb0c1936c4497d7f06b143241614d85a41fec12cd (patch)
tree82a527fc80f35ff3e110145a233e2d437734a71a /drivers/spi/spidev.c
parentf381f906955a2b0619b5557cc53aafcc7ef27be8 (diff)
parent66886337bf2a523aef76cff84c846335db5f85f9 (diff)
Merge tag 'spi-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
Pull spi updates from Mark Brown: "The major highlight this release is a refactoring of the core to allow us to run synchronous transfers in the context of the caller when there is no contention for the bus. This improves performance in the very common case by eliminating context switches and reducing the number of hardware setup and teardown operations we need to perform. Other changes: - New drivers for DLN-2 USB-SPI adapter and ST SPI controllers. - A big round of cleanups, performance and feature improvements for the xilinx driver from Ricardo Ribalda Delgado. - A wide range of smaller cleanups, fixes and feature improvements throughout the subsystem" * tag 'spi-v3.20' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (68 commits) spi: mxs: cleanup wait_for_completion return handling spi: ti-qspi: cleanup wait_for_completion return handling spi: spi-imx: cleanup wait_for_completion handling spi: sh-msiof: cleanup wait_for_completion return handling spi: match var type to return type of wait_for_completion spi: spi-pxa2xx: only include mach/dma.h for legacy DMA spi: atmel: cleanup wait_for_completion return handling spi: fsl-dspi: Remove possible memory leak of 'chip' spi: sh-msiof: Update calculation of frequency dividing spi: spidev: Convert buf pointers for 32-bit compat SPI_IOC_MESSAGE(n) spi/xilinx: Fix access invalid memory on xilinx_spi_tx spi: Revert "spi/xilinx: Remove iowrite/ioread wrappers" spi/xilinx: Check number of slaves range spi/xilinx: Use polling mode on small transfers spi/xilinx: Remove remaining_words driver data variable spi/xilinx: Remove iowrite/ioread wrappers spi/xilinx: Convert bits_per_word in bytes_per_word spi/xilinx: Convert remainding_bytes in remaining words spi/xilinx: Make spi_tx and spi_rx simmetric spi/xilinx: Remove rx_fn and tx_fn pointer ...
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 6941e04afb8..4eb7a980e67 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