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i2c: mux: reg Change ioread endianness for readback

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Reading the register (if allowed) after writing is to ensure writing
is completed on a posted bus. The endianness of reading doesn't matter.

Signed-off-by: York Sun <yorksun@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
York Sun 2015-09-02 11:40:46 -05:00 committed by Wolfram Sang
parent a05a34e7f6
commit 5a73882fd2
1 changed files with 14 additions and 14 deletions
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22
drivers/i2c/muxes/i2c-mux-reg.c
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@ -31,28 +31,28 @@ static int i2c_mux_reg_set(const struct regmux *mux, unsigned int chan_id)
if (!mux->data.reg) if (!mux->data.reg)
return -EINVAL; return -EINVAL;
/*
* Write to the register, followed by a read to ensure the write is
* completed on a "posted" bus, for example PCI or write buffers.
* The endianness of reading doesn't matter and the return data
* is not used.
*/
switch (mux->data.reg_size) { switch (mux->data.reg_size) {
case 4: case 4:
if (mux->data.little_endian) { if (mux->data.little_endian)
iowrite32(chan_id, mux->data.reg); iowrite32(chan_id, mux->data.reg);
if (!mux->data.write_only) else
ioread32(mux->data.reg);
} else {
iowrite32be(chan_id, mux->data.reg); iowrite32be(chan_id, mux->data.reg);
if (!mux->data.write_only) if (!mux->data.write_only)
ioread32(mux->data.reg); ioread32(mux->data.reg);
}
break; break;
case 2: case 2:
if (mux->data.little_endian) { if (mux->data.little_endian)
iowrite16(chan_id, mux->data.reg); iowrite16(chan_id, mux->data.reg);
if (!mux->data.write_only) else
ioread16(mux->data.reg);
} else {
iowrite16be(chan_id, mux->data.reg); iowrite16be(chan_id, mux->data.reg);
if (!mux->data.write_only) if (!mux->data.write_only)
ioread16be(mux->data.reg); ioread16(mux->data.reg);
}
break; break;
case 1: case 1:
iowrite8(chan_id, mux->data.reg); iowrite8(chan_id, mux->data.reg);