Merge tag 'spi-v3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
 "As well as the usual driver updates and cleanups there's a few
  improvements to the core here:

   - The start of some improvements to factor out more of the SPI
     message loop into the core.  Right now this is just simplifying the
     code a bit but hopefully next time around we'll also have managed
     to roll out some noticable performance improvements which drivers
     can take advantage of.
   - Support for loading modules for ACPI enumerated SPI devices.
   - Managed registration for SPI controllers.
   - Helper for another common I/O pattern"

* tag 'spi-v3.13' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (116 commits)
  spi/hspi: add device tree support
  spi: atmel: fix return value check in atmel_spi_probe()
  spi: spi-imx: only enable the clocks when we start to transfer a message
  spi/s3c64xx: Fix doubled clock disable on suspend
  spi/s3c64xx: Do not ignore return value of spi_master_resume/suspend
  spi: spi-mxs: Use u32 instead of uint32_t
  spi: spi-mxs: Don't set clock for each xfer
  spi: spi-mxs: Clean up setup_transfer function
  spi: spi-mxs: Remove check of spi mode bits
  spi: spi-mxs: Fix race in setup method
  spi: spi-mxs: Remove bogus setting of ssp clk rate field
  spi: spi-mxs: Remove full duplex check, spi core already does it
  spi: spi-mxs: Fix chip select control bits in DMA mode
  spi: spi-mxs: Fix extra CS pulses and read mode in multi-transfer messages
  spi: spi-mxs: Change flag arguments in txrx functions to bit flags
  spi: spi-mxs: Always clear INGORE_CRC, to keep CS asserted
  spi: spi-mxs: Remove mxs_spi_enable and mxs_spi_disable
  spi: spi-mxs: Always set LOCK_CS
  spi/s3c64xx: Add missing pm_runtime_put on setup fail
  spi/s3c64xx: Add missing pm_runtime_set_active() call in probe()
  ...

1 files changed, 18 insertions, 7 deletions

diff --git a/drivers/spi/spi-bitbang.c b/drivers/spi/spi-bitbang.c
index 8c11355dec23..bd222f6b677d 100644
--- a/drivers/spi/spi-bitbang.c
+++ b/drivers/spi/spi-bitbang.c
@@ -191,7 +191,7 @@ int spi_bitbang_setup(struct spi_device *spi)
 	bitbang = spi_master_get_devdata(spi->master);
 
 	if (!cs) {
-		cs = kzalloc(sizeof *cs, GFP_KERNEL);
+		cs = kzalloc(sizeof(*cs), GFP_KERNEL);
 		if (!cs)
 			return -ENOMEM;
 		spi->controller_state = cs;
@@ -258,7 +258,7 @@ static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t)
 
 static int spi_bitbang_prepare_hardware(struct spi_master *spi)
 {
-	struct spi_bitbang 	*bitbang;
+	struct spi_bitbang	*bitbang;
 	unsigned long		flags;
 
 	bitbang = spi_master_get_devdata(spi);
@@ -273,7 +273,7 @@ static int spi_bitbang_prepare_hardware(struct spi_master *spi)
 static int spi_bitbang_transfer_one(struct spi_master *master,
 				    struct spi_message *m)
 {
-	struct spi_bitbang 	*bitbang;
+	struct spi_bitbang	*bitbang;
 	unsigned		nsecs;
 	struct spi_transfer	*t = NULL;
 	unsigned		cs_change;
@@ -292,7 +292,7 @@ static int spi_bitbang_transfer_one(struct spi_master *master,
 	cs_change = 1;
 	status = 0;
 
-	list_for_each_entry (t, &m->transfers, transfer_list) {
+	list_for_each_entry(t, &m->transfers, transfer_list) {
 
 		/* override speed or wordsize? */
 		if (t->speed_hz || t->bits_per_word)
@@ -349,7 +349,8 @@ static int spi_bitbang_transfer_one(struct spi_master *master,
 		if (t->delay_usecs)
 			udelay(t->delay_usecs);
 
-		if (cs_change && !list_is_last(&t->transfer_list, &m->transfers)) {
+		if (cs_change &&
+		    !list_is_last(&t->transfer_list, &m->transfers)) {
 			/* sometimes a short mid-message deselect of the chip
 			 * may be needed to terminate a mode or command
 			 */
@@ -378,7 +379,7 @@ static int spi_bitbang_transfer_one(struct spi_master *master,
 
 static int spi_bitbang_unprepare_hardware(struct spi_master *spi)
 {
-	struct spi_bitbang 	*bitbang;
+	struct spi_bitbang	*bitbang;
 	unsigned long		flags;
 
 	bitbang = spi_master_get_devdata(spi);
@@ -414,10 +415,16 @@ static int spi_bitbang_unprepare_hardware(struct spi_master *spi)
  * This routine registers the spi_master, which will process requests in a
  * dedicated task, keeping IRQs unblocked most of the time.  To stop
  * processing those requests, call spi_bitbang_stop().
+ *
+ * On success, this routine will take a reference to master. The caller is
+ * responsible for calling spi_bitbang_stop() to decrement the reference and
+ * spi_master_put() as counterpart of spi_alloc_master() to prevent a memory
+ * leak.
  */
 int spi_bitbang_start(struct spi_bitbang *bitbang)
 {
 	struct spi_master *master = bitbang->master;
+	int ret;
 
 	if (!master || !bitbang->chipselect)
 		return -EINVAL;
@@ -449,7 +456,11 @@ int spi_bitbang_start(struct spi_bitbang *bitbang)
 	/* driver may get busy before register() returns, especially
 	 * if someone registered boardinfo for devices
 	 */
-	return spi_register_master(master);
+	ret = spi_register_master(spi_master_get(master));
+	if (ret)
+		spi_master_put(master);
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(spi_bitbang_start);