[FE training-materials-updates] Serial iomem lab: fix footnote

[Michael Opdenacker]

Repository : git://git.free-electrons.com/training-materials.git

On branch  : master
Link       : http://git.free-electrons.com/training-materials/commit/?id=51b2b4bdfd7ac3a3a4372dc20fb4fe0817ecaea5

>---------------------------------------------------------------

commit 51b2b4bdfd7ac3a3a4372dc20fb4fe0817ecaea5
Author: Michael Opdenacker <michael.opdenacker at free-electrons.com>
Date:   Fri Dec 6 09:45:38 2013 +0100

    Serial iomem lab: fix footnote
    
    - The footnote was giving the impression
      that we were asking to multiply the offset by 4^12
      (the footnote number looked like a power, by being
      next to a digit)
    
    Signed-off-by: Michael Opdenacker <michael.opdenacker at free-electrons.com>


>---------------------------------------------------------------

51b2b4bdfd7ac3a3a4372dc20fb4fe0817ecaea5
 labs/kernel-serial-iomem/kernel-serial-iomem.tex |   15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/labs/kernel-serial-iomem/kernel-serial-iomem.tex b/labs/kernel-serial-iomem/kernel-serial-iomem.tex
index e2e5cf4..efa2b9c 100644
--- a/labs/kernel-serial-iomem/kernel-serial-iomem.tex
+++ b/labs/kernel-serial-iomem/kernel-serial-iomem.tex
@@ -211,10 +211,12 @@ pointer to an \code{feserial_dev} structure and an \code{offset} integer
 offset.
 
 In this function, read from a 32 bits register at the base virtual
-address for the device plus the offset multiplied by 4\footnote{You have
-to multiply by 4 because we are using a void* pointer so pointer
-arithmetic will use the offset as bytes whereas we are using 32 bits
-registers.}, and return this value.
+address for the device plus the offset multiplied by 4.
+
+All the UART register offsets have standardized values, shared between
+several types of serial drivers (see
+\code{include/uapi/linux/serial_reg.h}). This explains why they are not
+completely ready to use and we have to multiply them by 4 for OMAP SoCs.
 
 Create a similar \code{reg_write()} routine, writing an unsigned integer
 value at a given integer offset (don't forget to multiply it by 4) from
@@ -225,11 +227,6 @@ offset. Your prototype should look like:
     static void reg_write(struct feserial_dev *dev, int val, int off);
 \end{verbatim}
 
-All the UART register offsets have standardized values, shared between
-several types of serial drivers (see
-\code{include/uapi/linux/serial_reg.h}). This explains why they are not
-completely ready to use and we have to multiply them by 4 for OMAP SoCs.
-
 We are now ready to read and write registers!
 
 \subsection{Power management initialization}