[PATCH 2/2] ARM: OMAP2+: PM: clean up omap_set_pwrdm_state()

Paul Walmsley
2012-01-30T09:43:18Z

Clean up a few different parts of omap_set_pwrdm_state():

- Remove a superfluous call to pwrdm_state_switch(). Not needed
unless LOWPOWERSTATECHANGE is used, because the state switch code is
called by either clkdm_sleep() or clkdm_allow_idle().

- Add code to wait for the power state transition in the OMAP4+ low
power state change. This is speculative, so I would particularly
appreciate feedback on this part.

- Remove a superfluous call to pwrdm_read_pwrst().

- Update variable names to be more meaningful (hopefully) and precise.

- Fix an error path bug that would not place the clockdomain back into
hardware-supervised idle or sleep mode if the power state could not
be programmed.

The documentation for this function still needs major improvements;
that's left for a later patch.

Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Kevin Hilman <khilman@ti.com>
Cc: Rajendra Nayak <rnayak@ti.com>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Tero Kristo <t-kristo@ti.com>
---
arch/arm/mach-omap2/pm.c | 39 +++++++++++++++++----------------------
1 files changed, 17 insertions(+), 22 deletions(-)

diff --git a/arch/arm/mach-omap2/pm.c b/arch/arm/mach-omap2/pm.c
index 1881fe9..137d2d9 100644
--- a/arch/arm/mach-omap2/pm.c
+++ b/arch/arm/mach-omap2/pm.c
@@ -72,28 +72,27 @@ static void omap2_init_processor_devices(void)
* This sets pwrdm state (other than mpu & core. Currently only ON &
* RET are supported.
*/
-int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 state)
+int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 pwrst)
{
- u32 cur_state;
- int sleep_switch = -1;
- int ret = 0;
- int hwsup = 0;
+ u8 curr_pwrst, next_pwrst;
+ int sleep_switch = -1, ret = 0, hwsup = 0;

- if (pwrdm == NULL || IS_ERR(pwrdm))
+ if (!pwrdm || IS_ERR(pwrdm))
return -EINVAL;

- while (!(pwrdm->pwrsts & (1 << state))) {
- if (state == PWRDM_POWER_OFF)
+ while (!(pwrdm->pwrsts & (1 << pwrst))) {
+ if (pwrst == PWRDM_POWER_OFF)
return ret;
- state--;
+ pwrst--;
}

- cur_state = pwrdm_read_next_pwrst(pwrdm);
- if (cur_state == state)
+ next_pwrst = pwrdm_read_next_pwrst(pwrdm);
+ if (next_pwrst == pwrst)
return ret;

- if (pwrdm_read_pwrst(pwrdm) < PWRDM_POWER_ON) {
- if ((pwrdm_read_pwrst(pwrdm) > state) &&
+ curr_pwrst = pwrdm_read_pwrst(pwrdm);
+ if (curr_pwrst < PWRDM_POWER_ON) {
+ if ((curr_pwrst > pwrst) &&
(pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE)) {
sleep_switch = LOWPOWERSTATE_SWITCH;
} else {
@@ -103,12 +102,10 @@ int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 state)
}
}

- ret = pwrdm_set_next_pwrst(pwrdm, state);
- if (ret) {
- pr_err("%s: unable to set state of powerdomain: %s\n",
+ ret = pwrdm_set_next_pwrst(pwrdm, pwrst);
+ if (ret)
+ pr_err("%s: unable to set power state of powerdomain: %s\n",
__func__, pwrdm->name);
- goto err;
- }

switch (sleep_switch) {
case FORCEWAKEUP_SWITCH:
@@ -119,13 +116,11 @@ int omap_set_pwrdm_state(struct powerdomain *pwrdm, u32 state)
break;
case LOWPOWERSTATE_SWITCH:
pwrdm_set_lowpwrstchange(pwrdm);
+ pwrdm_wait_transition(pwrdm);
+ pwrdm_state_switch(pwrdm);
break;
- default:
- return ret;
}

- pwrdm_state_switch(pwrdm);
-err:
return ret;
}