On Tue, Mar 24, 2020 at 09:07:12PM +0800, Kai-Heng Feng wrote:
> Nvidia card may come with a "phantom" UCSI device, and its driver gets
> stuck in probe routine, prevents any system PM operations like suspend.
>
> When the target time equals to jiffies, it's not included by
> time_is_before_jiffies(). So let's use a boolean to make sure the
> operation is done or timeout.
Thank you for an update, my comments below.
> unsigned long target = jiffies + msecs_to_jiffies(1000);
> u32 val;
> + bool done = false;
>
> do {
> val = readl(i2cd->regs + I2C_MST_CNTL);
> - if (!(val & I2C_MST_CNTL_CYCLE_TRIGGER))
> - break;
> - if ((val & I2C_MST_CNTL_STATUS) !=
> - I2C_MST_CNTL_STATUS_BUS_BUSY)
> + if (!(val & I2C_MST_CNTL_CYCLE_TRIGGER)
> + || (val & I2C_MST_CNTL_STATUS) !=
> + I2C_MST_CNTL_STATUS_BUS_BUSY) {
Bad formatting. But see below.
> + done = true;
> break;
> + }
> usleep_range(500, 600);
> } while (time_is_after_jiffies(target));
>
> - if (time_is_before_jiffies(target)) {
> + if (!done) {
> dev_err(i2cd->dev, "i2c timeout error %x\n", val);
> return -ETIMEDOUT;
> }
Overall it can use simple tries since you already have sleep inside, but
moreover, you may simple switch to readl_poll_timeout() this entire
loop.
--
With Best Regards,
Andy Shevchenko
