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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org > > @@ -474,6 +608,11 @@ static void spacemit_i2c_calc_timeout(struct spacemit_i2c_dev *i2c) > > unsigned long timeout; > > int idx = 0, cnt = 0; > > + if (i2c->use_pio) { > > + i2c->adapt.timeout = msecs_to_jiffies(SPACEMIT_WAIT_TIMEOUT); > > Again, why is a rough 1000 millisecond timeout OK for PIO, while a > fairly precise timeout value based on the number of bytes to be > transferred and the transfer bit rate computed for interrupt mode? Sorry I didn't see this. In interrupt-driven mode we wait for a single completion event, so the timeout needs to reflect the worst-case transfer duration to avoid spurious timeouts. In PIO mode the loop is driven by FIFO/status progress, and the timeout is only a safeguard against a stalled bus rather than an exact transfer time. Therefore a simple conservative value is sufficient there. - Troy _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv