From: Martin Sperl <redacted>

Under some circumstances the default 30 us polling limit is not optimal
and may lead to long delays because we are waiting on an interrupt.
with this patch we have the possibility to influence this policy.

So make this limit (in us) configurable via a module parameters
(but also modifyable via /sys/modules/...)

Signed-off-by: Martin Sperl <redacted>

---
Changelog:
  V1 -> V2: remove the dependency on a different patchset focused on
	    making cs_change delay configurable

---
 drivers/spi/spi-bcm2835aux.c | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c
index d2b58060b333..df065108122b 100644
--- a/drivers/spi/spi-bcm2835aux.c
+++ b/drivers/spi/spi-bcm2835aux.c

@@ -37,6 +37,12 @@
 #include <linux/spi/spi.h>
 #include <linux/spinlock.h>

+/* define polling limits */
+unsigned int polling_limit_us = 30;
+module_param(polling_limit_us, uint, 0664);
+MODULE_PARM_DESC(polling_limit_us,
+		 "time in us to run a transfer in polling mode\n");
+