| Message ID | alpine.DEB.2.00.1304011024090.28273@utopia.booyaka.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 2013?04?01? 18:25, Paul Walmsley wrote: > Hi, > > On Thu, 14 Mar 2013, Chen Gang wrote: > >> >> if pwrdm_read_pwrst returns negative number, curr_pwrst can not notice it. >> since really need check curr_pwrst whether is negative, >> need let the check valid in _pwrdm_save_clkdm_state_and_activate. >> and also better to check the return value of pwrdm_read_pwrst, firstly. >> >> Signed-off-by: Chen Gang <gang.chen@asianux.com> > > thanks for reporting this and sending a suggested fix. The following > patch is what I've queued here, which should deal with the root cause > without the casts. > > yours (patch below) is simpler and clearer than mine. thanks. :-) > - Paul > > From: Paul Walmsley <paul@pwsan.com> > Date: Sun, 31 Mar 2013 20:22:22 -0600 > Subject: [PATCH] ARM: OMAP2+: powerdomain: avoid testing whether an unsigned > char is less than 0 > > _pwrdm_save_clkdm_state_and_activate() tried to test one of its > unsigned arguments to determine whether it was less than zero. Fix by > moving the error test to the caller. > > Reported-by: Chen Gang <gang.chen@asianux.com> > Signed-off-by: Paul Walmsley <paul@pwsan.com> > --- > arch/arm/mach-omap2/powerdomain.c | 18 ++++++++---------- > 1 file changed, 8 insertions(+), 10 deletions(-) > > diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c > index 8e61d80..89cad4a 100644 > --- a/arch/arm/mach-omap2/powerdomain.c > +++ b/arch/arm/mach-omap2/powerdomain.c > @@ -52,7 +52,6 @@ enum { > #define ALREADYACTIVE_SWITCH 0 > #define FORCEWAKEUP_SWITCH 1 > #define LOWPOWERSTATE_SWITCH 2 > -#define ERROR_SWITCH 3 > > /* pwrdm_list contains all registered struct powerdomains */ > static LIST_HEAD(pwrdm_list); > @@ -233,10 +232,7 @@ static u8 _pwrdm_save_clkdm_state_and_activate(struct powerdomain *pwrdm, > { > u8 sleep_switch; > > - if (curr_pwrst < 0) { > - WARN_ON(1); > - sleep_switch = ERROR_SWITCH; > - } else if (curr_pwrst < PWRDM_POWER_ON) { > + if (curr_pwrst < PWRDM_POWER_ON) { > if (curr_pwrst > pwrst && > pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE && > arch_pwrdm->pwrdm_set_lowpwrstchange) { > @@ -1091,7 +1087,8 @@ int pwrdm_post_transition(struct powerdomain *pwrdm) > */ > int omap_set_pwrdm_state(struct powerdomain *pwrdm, u8 pwrst) > { > - u8 curr_pwrst, next_pwrst, sleep_switch; > + u8 next_pwrst, sleep_switch; > + int curr_pwrst; > int ret = 0; > bool hwsup = false; > > @@ -1107,16 +1104,17 @@ int omap_set_pwrdm_state(struct powerdomain *pwrdm, u8 pwrst) > pwrdm_lock(pwrdm); > > curr_pwrst = pwrdm_read_pwrst(pwrdm); > + if (curr_pwrst < 0) { > + ret = -EINVAL; > + goto osps_out; > + } > + > next_pwrst = pwrdm_read_next_pwrst(pwrdm); > if (curr_pwrst == pwrst && next_pwrst == pwrst) > goto osps_out; > > sleep_switch = _pwrdm_save_clkdm_state_and_activate(pwrdm, curr_pwrst, > pwrst, &hwsup); > - if (sleep_switch == ERROR_SWITCH) { > - ret = -EINVAL; > - goto osps_out; > - } > > ret = pwrdm_set_next_pwrst(pwrdm, pwrst); > if (ret) >
diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c index 8e61d80..89cad4a 100644 --- a/arch/arm/mach-omap2/powerdomain.c +++ b/arch/arm/mach-omap2/powerdomain.c @@ -52,7 +52,6 @@ enum { #define ALREADYACTIVE_SWITCH 0 #define FORCEWAKEUP_SWITCH 1 #define LOWPOWERSTATE_SWITCH 2 -#define ERROR_SWITCH 3 /* pwrdm_list contains all registered struct powerdomains */ static LIST_HEAD(pwrdm_list); @@ -233,10 +232,7 @@ static u8 _pwrdm_save_clkdm_state_and_activate(struct powerdomain *pwrdm, { u8 sleep_switch; - if (curr_pwrst < 0) { - WARN_ON(1); - sleep_switch = ERROR_SWITCH; - } else if (curr_pwrst < PWRDM_POWER_ON) { + if (curr_pwrst < PWRDM_POWER_ON) { if (curr_pwrst > pwrst && pwrdm->flags & PWRDM_HAS_LOWPOWERSTATECHANGE && arch_pwrdm->pwrdm_set_lowpwrstchange) { @@ -1091,7 +1087,8 @@ int pwrdm_post_transition(struct powerdomain *pwrdm) */ int omap_set_pwrdm_state(struct powerdomain *pwrdm, u8 pwrst) { - u8 curr_pwrst, next_pwrst, sleep_switch; + u8 next_pwrst, sleep_switch; + int curr_pwrst; int ret = 0; bool hwsup = false; @@ -1107,16 +1104,17 @@ int omap_set_pwrdm_state(struct powerdomain *pwrdm, u8 pwrst) pwrdm_lock(pwrdm); curr_pwrst = pwrdm_read_pwrst(pwrdm); + if (curr_pwrst < 0) { + ret = -EINVAL; + goto osps_out; + } + next_pwrst = pwrdm_read_next_pwrst(pwrdm); if (curr_pwrst == pwrst && next_pwrst == pwrst) goto osps_out; sleep_switch = _pwrdm_save_clkdm_state_and_activate(pwrdm, curr_pwrst, pwrst, &hwsup); - if (sleep_switch == ERROR_SWITCH) { - ret = -EINVAL; - goto osps_out; - } ret = pwrdm_set_next_pwrst(pwrdm, pwrst); if (ret)