From 7dc9fbc342deb2e2658ebdecb5ffd7ff57945a66 Mon Sep 17 00:00:00 2001
From: Mark Brown <broonie@kernel.org>
Date: Thu, 20 Aug 2015 11:52:18 -0700
Subject: spi: Fall back to master maximum speed if no slave speed specified

If a slave appears with no maximum transfer speed specified fall back to
using the maximum for the master instead.  It's questionable if we
should let slaves do this but let's be defensive.

Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index cf8b91b..637d892 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1860,6 +1860,8 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
 
 		if (!xfer->speed_hz)
 			xfer->speed_hz = spi->max_speed_hz;
+		if (!xfer->speed_hz)
+			xfer->speed_hz = master->max_speed_hz;
 
 		if (master->max_speed_hz &&
 		    xfer->speed_hz > master->max_speed_hz)
-- 
cgit v0.10.2


From 63ab645f4d8b2dc1351c41751e7ebb1b3f1c99d3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20Br=C3=BCns?= <stefan.bruens@rwth-aachen.de>
Date: Sun, 23 Aug 2015 16:06:30 +0200
Subject: spi: check bits_per_word in spi_setup
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

This allows drivers for devices connected via SPI to check if the
controller supports a given bits_per_word value during setup.
Currently any BPW value is accepted durings setup, and transfers
are rejected later.

Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 637d892..829323ce 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -1740,6 +1740,20 @@ EXPORT_SYMBOL_GPL(spi_busnum_to_master);
  * other core methods are currently defined as inline functions.
  */
 
+static int __spi_validate_bits_per_word(struct spi_master *master, u8 bits_per_word)
+{
+	if (master->bits_per_word_mask) {
+		/* Only 32 bits fit in the mask */
+		if (bits_per_word > 32)
+			return -EINVAL;
+		if (!(master->bits_per_word_mask &
+				SPI_BPW_MASK(bits_per_word)))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
 /**
  * spi_setup - setup SPI mode and clock rate
  * @spi: the device whose settings are being modified
@@ -1798,6 +1812,9 @@ int spi_setup(struct spi_device *spi)
 	if (!spi->bits_per_word)
 		spi->bits_per_word = 8;
 
+	if (__spi_validate_bits_per_word(spi->master, spi->bits_per_word))
+		return -EINVAL;
+
 	if (!spi->max_speed_hz)
 		spi->max_speed_hz = spi->master->max_speed_hz;
 
@@ -1867,14 +1884,8 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
 		    xfer->speed_hz > master->max_speed_hz)
 			xfer->speed_hz = master->max_speed_hz;
 
-		if (master->bits_per_word_mask) {
-			/* Only 32 bits fit in the mask */
-			if (xfer->bits_per_word > 32)
-				return -EINVAL;
-			if (!(master->bits_per_word_mask &
-					BIT(xfer->bits_per_word - 1)))
-				return -EINVAL;
-		}
+		if (__spi_validate_bits_per_word(master, xfer->bits_per_word))
+			return -EINVAL;
 
 		/*
 		 * SPI transfer length should be multiple of SPI word size
-- 
cgit v0.10.2