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Felipe Balbi 540a4790f7 i2c: omap: simplify omap_i2c_ack_stat()

stat & BIT(1) is the same as BIT(1), so let's
simplify things a bit by removing "stat &" from
all omap_i2c_ack_stat() calls.

Code snippet (extremely simplified):

if (stat & NACK) {
        ...
        omap_i2c_ack_stat(dev, stat & NACK);
}

if (stat & RDR) {
        ...
        omap_i2c_ack_stat(dev, stat & RDR);
}

and so on. The tricky place is only WRT errata handling, for example:

if (*stat & (NACK | AL)) {
        omap_i2c_ack_stat(dev, *stat & (XRDY | XDR));
        ...
}

but in this case, the errata says we must clear XRDY and XDR if that
errata triggers, so if they just got enabled or not, it doesn't matter.

Another tricky place is RDR | RRDY (likewise for XDR | XRDY):

if (stat & (RDR | RRDY)) {
        ...
        omap_i2c_ack_stat(dev, stat & (RDR | RRDY));
}

again here there will be no issues because those IRQs never fire
simultaneously and one will only after after we have handled the
previous, that's because the same FIFO is used anyway and we won't shift
data into FIFO until we tell the IP "hey, I'm done with the FIFO, you
can shift more data"

Signed-off-by: Felipe Balbi <balbi@ti.com>
Reviewed-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
[Added the explaination from the discurssion to the commit logs]
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>

2012-09-12 15:02:14 +02:00

algos

i2c: Split I2C_M_NOSTART support out of I2C_FUNC_PROTOCOL_MANGLING

2012-05-30 10:55:34 +02:00

busses

i2c: omap: simplify omap_i2c_ack_stat()

2012-09-12 15:02:14 +02:00

muxes

i2c: Update Guenter Roeck's e-mail address

2012-07-24 14:13:56 +02:00

i2c-boardinfo.c

i2c: Update the FSF address