On Fri, 29 Jan 2016 23:26:52 -0500
"David Rivshin (Allworx)" <drivshin.allworx@xxxxxxxxx> wrote:
> From: David Rivshin <drivshin@xxxxxxxxxxx>
>
> Add sanity checking to ensure that we do not program load or match
> values that are out of range if a user requests period or duty_cycle
> values which are not achievable. The match value cannot be less than
> the load value (but can be equal), and neither can be 0xffffffff.
> This means that there must be at least one fclk cycle between load
> and match, and another between match and overflow.
>
> Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode
> timers") Signed-off-by: David Rivshin <drivshin@xxxxxxxxxxx>
> ---
[...]
> @@ -149,6 +149,24 @@ static int pwm_omap_dmtimer_config(struct pwm_chip *chip,
> period_cycles = pwm_omap_dmtimer_get_clock_cycles(clk_rate, period_ns);
> duty_cycles = pwm_omap_dmtimer_get_clock_cycles(clk_rate, duty_ns);
>
> + if (period_cycles < 2) {
> + dev_info(chip->dev,
> + "period %dns is too short for clock rate %luHz\n",
> + period_ns, clk_rate);
> + goto err_einval;
> + }
[...]
I had some second thoughts on this over the weekend:
1) Perhaps the return should be -ERANGE instead of -EINVAL for this case?
2) Is dev_info() too severe for this? Perhaps dev_dbg() would be better?
Any preferences?
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
