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由 Linus Walleij 提交于
Since commit c4dd1ba3 ("mfd: stmpe: Add reset support for all STMPE variant") we're resetting the STMPE expanders before use. This caused a regression on the STMP2401 on the Nomadik NHK8815: stmpe-i2c 0-0043: stmpe2401 detected, chip id: 0x101 nmk-i2c 101f8000.i2c0: write to slave 0x43 timed out nmk-i2c 101f8000.i2c0: no ack received after address transmission stmpe-i2c 0-0044: stmpe2401 detected, chip id: 0x101 nmk-i2c 101f8000.i2c0: write to slave 0x44 timed out nmk-i2c 101f8000.i2c0: no ack received after address transmission It turns out that we start to poll for the reset bit to go low again too quickly: the STMPE2401 is not yet online and ready to be asked for the status of the RESET bit. By introducing a 10ms delay before starting to hammer the register for information, we get back to normal: stmpe-i2c 0-0043: stmpe2401 detected, chip id: 0x101 stmpe-i2c 0-0044: stmpe2401 detected, chip id: 0x101 Cc: stable@vger.kernel.org Cc: Amelie Delaunay <amelie.delaunay@st.com> Fixes: c4dd1ba3 ("mfd: stmpe: Add reset support for all STMPE variant") Signed-off-by: NLinus Walleij <linus.walleij@linaro.org> Acked-by: NPatrice Chotard <patrice.chotard@st.com> Signed-off-by: NLee Jones <lee.jones@linaro.org>
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