diff options
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/mach-omap2/clock.c | 135 | ||||
| -rw-r--r-- | arch/arm/mach-omap2/clockdomain.c | 10 |
2 files changed, 99 insertions, 46 deletions
diff --git a/arch/arm/mach-omap2/clock.c b/arch/arm/mach-omap2/clock.c index d1f115d0edad..a6d0b34b7990 100644 --- a/arch/arm/mach-omap2/clock.c +++ b/arch/arm/mach-omap2/clock.c @@ -37,9 +37,9 @@ u8 cpu_mask; -/*------------------------------------------------------------------------- - * OMAP2/3/4 specific clock functions - *-------------------------------------------------------------------------*/ +/* + * OMAP2+ specific clock functions + */ /* Private functions */ @@ -71,20 +71,6 @@ static void _omap2_module_wait_ready(struct clk *clk) clk->name); } -/* Enables clock without considering parent dependencies or use count - * REVISIT: Maybe change this to use clk->enable like on omap1? - */ -static int _omap2_clk_enable(struct clk *clk) -{ - return clk->ops->enable(clk); -} - -/* Disables clock without considering parent dependencies or use count */ -static void _omap2_clk_disable(struct clk *clk) -{ - clk->ops->disable(clk); -} - /* Public functions */ /** @@ -245,46 +231,106 @@ const struct clkops clkops_omap2_dflt = { .disable = omap2_dflt_clk_disable, }; +/** + * omap2_clk_disable - disable a clock, if the system is not using it + * @clk: struct clk * to disable + * + * Decrements the usecount on struct clk @clk. If there are no users + * left, call the clkops-specific clock disable function to disable it + * in hardware. If the clock is part of a clockdomain (which they all + * should be), request that the clockdomain be disabled. (It too has + * a usecount, and so will not be disabled in the hardware until it no + * longer has any users.) If the clock has a parent clock (most of + * them do), then call ourselves, recursing on the parent clock. This + * can cause an entire branch of the clock tree to be powered off by + * simply disabling one clock. Intended to be called with the clockfw_lock + * spinlock held. No return value. + */ void omap2_clk_disable(struct clk *clk) { - if (clk->usecount > 0 && !(--clk->usecount)) { - _omap2_clk_disable(clk); - if (clk->parent) - omap2_clk_disable(clk->parent); - if (clk->clkdm) - omap2_clkdm_clk_disable(clk->clkdm, clk); - + if (clk->usecount == 0) { + WARN(1, "clock: %s: omap2_clk_disable() called, but usecount " + "already 0?", clk->name); + return; } + + pr_debug("clock: %s: decrementing usecount\n", clk->name); + + clk->usecount--; + + if (clk->usecount > 0) + return; + + pr_debug("clock: %s: disabling in hardware\n", clk->name); + + clk->ops->disable(clk); + + if (clk->clkdm) + omap2_clkdm_clk_disable(clk->clkdm, clk); + + if (clk->parent) + omap2_clk_disable(clk->parent); } +/** + * omap2_clk_enable - request that the system enable a clock + * @clk: struct clk * to enable + * + * Increments the usecount on struct clk @clk. If there were no users + * previously, then recurse up the clock tree, enabling all of the + * clock's parents and all of the parent clockdomains, and finally, + * enabling @clk's clockdomain, and @clk itself. Intended to be + * called with the clockfw_lock spinlock held. Returns 0 upon success + * or a negative error code upon failure. + */ int omap2_clk_enable(struct clk *clk) { - int ret = 0; + int ret; - if (clk->usecount++ == 0) { - if (clk->clkdm) - omap2_clkdm_clk_enable(clk->clkdm, clk); + pr_debug("clock: %s: incrementing usecount\n", clk->name); - if (clk->parent) { - ret = omap2_clk_enable(clk->parent); - if (ret) - goto err; - } + clk->usecount++; + + if (clk->usecount > 1) + return 0; - ret = _omap2_clk_enable(clk); + pr_debug("clock: %s: enabling in hardware\n", clk->name); + + if (clk->parent) { + ret = omap2_clk_enable(clk->parent); if (ret) { - if (clk->parent) - omap2_clk_disable(clk->parent); + WARN(1, "clock: %s: could not enable parent %s: %d\n", + clk->name, clk->parent->name, ret); + goto oce_err1; + } + } - goto err; + if (clk->clkdm) { + ret = omap2_clkdm_clk_enable(clk->clkdm, clk); + if (ret) { + WARN(1, "clock: %s: could not enable clockdomain %s: " + "%d\n", clk->name, clk->clkdm->name, ret); + goto oce_err2; } } - return ret; -err: + ret = clk->ops->enable(clk); + if (ret) { + WARN(1, "clock: %s: could not enable: %d\n", clk->name, ret); + goto oce_err3; + } + + return 0; + +oce_err3: if (clk->clkdm) omap2_clkdm_clk_disable(clk->clkdm, clk); +oce_err2: + if (clk->parent) + omap2_clk_disable(clk->parent); +oce_err1: clk->usecount--; + return ret; } @@ -325,9 +371,9 @@ const struct clkops clkops_omap3_noncore_dpll_ops = { #endif -/*------------------------------------------------------------------------- - * Omap2 clock reset and init functions - *-------------------------------------------------------------------------*/ +/* + * OMAP2+ clock reset and init functions + */ #ifdef CONFIG_OMAP_RESET_CLOCKS void omap2_clk_disable_unused(struct clk *clk) @@ -344,8 +390,9 @@ void omap2_clk_disable_unused(struct clk *clk) if (cpu_is_omap34xx()) { omap2_clk_enable(clk); omap2_clk_disable(clk); - } else - _omap2_clk_disable(clk); + } else { + clk->ops->disable(clk); + } if (clk->clkdm != NULL) pwrdm_clkdm_state_switch(clk->clkdm); } diff --git a/arch/arm/mach-omap2/clockdomain.c b/arch/arm/mach-omap2/clockdomain.c index b26d30a14303..b87ad66f083e 100644 --- a/arch/arm/mach-omap2/clockdomain.c +++ b/arch/arm/mach-omap2/clockdomain.c @@ -978,7 +978,7 @@ int omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk) * downstream clocks for debugging purposes? */ - if (!clkdm || !clk || !clkdm->clkstctrl_reg) + if (!clkdm || !clk) return -EINVAL; if (atomic_inc_return(&clkdm->usecount) > 1) @@ -989,6 +989,9 @@ int omap2_clkdm_clk_enable(struct clockdomain *clkdm, struct clk *clk) pr_debug("clockdomain: clkdm %s: clk %s now enabled\n", clkdm->name, clk->name); + if (!clkdm->clkstctrl_reg) + return 0; + v = omap2_clkdm_clktrctrl_read(clkdm); if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) || @@ -1030,7 +1033,7 @@ int omap2_clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk) * downstream clocks for debugging purposes? */ - if (!clkdm || !clk || !clkdm->clkstctrl_reg) + if (!clkdm || !clk) return -EINVAL; #ifdef DEBUG @@ -1048,6 +1051,9 @@ int omap2_clkdm_clk_disable(struct clockdomain *clkdm, struct clk *clk) pr_debug("clockdomain: clkdm %s: clk %s now disabled\n", clkdm->name, clk->name); + if (!clkdm->clkstctrl_reg) + return 0; + v = omap2_clkdm_clktrctrl_read(clkdm); if ((cpu_is_omap34xx() && v == OMAP34XX_CLKSTCTRL_ENABLE_AUTO) || |
