This adds helper function for most typical I2C register write. Main
reason was the fact I2C messages are are needed to split smaller parts
as I2C-adapters cannot send all long messages used.
Basically there is three different kind of I2C register access used:
* register write (I2C write)
* register read (I2C write + I2C read)
* register read (I2C read)
Register read is usually done using write+read combination (with
REPEATED START) and almost all I2C-adapters we have can handle it. Some
rare situations simple read is used. That means for example reading
small amount of registers starting from register 0 and thus register
write for setting desired register is not needed. Other used rarely used
combination for register read is simple register write (for set desired
reg) and then perform simple register read. It looks like write+read but
there is no REPEATED START, both messages are own transactions. I hope
this story gives better understanding :)
At that point, I just implemented simple register write as a example. It
does not have even any configuration for "register map", like register
address length nor register value length. It just assumes register is
one byte wide for both address and value. Lets add those later when needed.
And here is the list of drivers I have been working and this kind of
splitting have been one problematic issue;
* RTL2832U & RTL2832
* RTL2831U & RTL2830
* AF9015 & TDA18212
* AF9015 & TDA18271
* EM28xx & TDA10071
* Anysee & CX24116
* <demod driver not released yet>
So, as you can see, there is a lot of drivers need splitting!
Any comments?
Antti Palosaari (2):
dvb-core: add generic helper function for I2C register write
tda18218: use generic dvb_wr_regs()
drivers/media/common/tuners/tda18218.c | 69
+++++---------------------
drivers/media/common/tuners/tda18218_priv.h | 3 +
drivers/media/dvb/dvb-core/Makefile | 2 +-
drivers/media/dvb/dvb-core/dvb_generic.c | 48 ++++++++++++++++++
drivers/media/dvb/dvb-core/dvb_generic.h | 21 ++++++++
5 files changed, 87 insertions(+), 56 deletions(-)
create mode 100644 drivers/media/dvb/dvb-core/dvb_generic.c
create mode 100644 drivers/media/dvb/dvb-core/dvb_generic.h
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1.7.4.4
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http://palosaari.fi/
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