iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

drivers/clocksource/timer-ti-dm: Don't call clk_get_rate() in stop function

Browse Source 
clk_get_rate() might sleep, and that prevents dm-timer based PWM from being
used from atomic context.

Fix that by getting fclk rate in probe() and using a notifier in case rate
changes.

Fixes: af04aa856e ("ARM: OMAP: Move dmtimer driver out of plat-omap to drivers under clocksource")
Signed-off-by: Ivaylo Dimitrov <ivo.g.dimitrov.75@gmail.com>
Reviewed-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/1696312220-11550-1-git-send-email-ivo.g.dimitrov.75@gmail.com
This commit is contained in:
Ivaylo Dimitrov 2023-10-03 08:50:20 +03:00 committed by Daniel Lezcano
parent 8051a993ce
commit 12590d4d0e
1 changed files with 28 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
drivers/clocksource/timer-ti-dm.c
View File

@ -140,6 +140,8 @@ struct dmtimer {
struct platform_device *pdev;
struct list_head node;
struct notifier_block nb;
struct notifier_block fclk_nb;
unsigned long fclk_rate;
};
static u32 omap_reserved_systimers;
@ -253,8 +255,7 @@ static inline void __omap_dm_timer_enable_posted(struct dmtimer *timer)
timer->posted = OMAP_TIMER_POSTED;
}
static inline void __omap_dm_timer_stop(struct dmtimer *timer,
unsigned long rate)
static inline void __omap_dm_timer_stop(struct dmtimer *timer)
{
u32 l;
@ -269,7 +270,7 @@ static inline void __omap_dm_timer_stop(struct dmtimer *timer,
* Wait for functional clock period x 3.5 to make sure that
* timer is stopped
*/
udelay(3500000 / rate + 1);
udelay(3500000 / timer->fclk_rate + 1);
#endif
}
@ -348,6 +349,21 @@ static int omap_timer_context_notifier(struct notifier_block *nb,
return NOTIFY_OK;
}
static int omap_timer_fclk_notifier(struct notifier_block *nb,
unsigned long event, void *data)
{
struct clk_notifier_data *clk_data = data;
struct dmtimer *timer = container_of(nb, struct dmtimer, fclk_nb);
switch (event) {
case POST_RATE_CHANGE:
timer->fclk_rate = clk_data->new_rate;
return NOTIFY_OK;
default:
return NOTIFY_DONE;
}
}
static int omap_dm_timer_reset(struct dmtimer *timer)
{
u32 l, timeout = 100000;
@ -754,7 +770,6 @@ static int omap_dm_timer_stop(struct omap_dm_timer *cookie)
{
struct dmtimer *timer;
struct device *dev;
unsigned long rate = 0;
timer = to_dmtimer(cookie);
if (unlikely(!timer))
@ -762,10 +777,7 @@ static int omap_dm_timer_stop(struct omap_dm_timer *cookie)
dev = &timer->pdev->dev;
if (!timer->omap1)
rate = clk_get_rate(timer->fclk);
__omap_dm_timer_stop(timer, rate);
__omap_dm_timer_stop(timer);
pm_runtime_put_sync(dev);
@ -1124,6 +1136,14 @@ static int omap_dm_timer_probe(struct platform_device *pdev)
timer->fclk = devm_clk_get(dev, "fck");
if (IS_ERR(timer->fclk))
return PTR_ERR(timer->fclk);
timer->fclk_nb.notifier_call = omap_timer_fclk_notifier;
ret = devm_clk_notifier_register(dev, timer->fclk,
&timer->fclk_nb);
if (ret)
return ret;
timer->fclk_rate = clk_get_rate(timer->fclk);
} else {
timer->fclk = ERR_PTR(-ENODEV);
}