Add new function omap_device_has_lost_context() as a simple check to be used after omap_device_enable() to determine if device has lost context (and thus needs context restore.)
Motivation: Currently, each driver needs to read the context-loss count before suspend, and again upon resume to determine if device context needs to be restored. Rather than duplicating this process across all drivers, move it into omap_device. After omap_device_enable(), omap_device_has_lost_context() can be called to determine if context was lost. The hard work is done inside the powerdomain layer where a simple flag is checked. The flag is cleared in the pre-transition call back, and conditionally set post-transition based on either an off-mode transition or a memory or logic off transition. Signed-off-by: Kevin Hilman <[email protected]> --- Updates from previous version: - also handles memory and logic off transitions - no longer keeps track of pre- and post transition counters arch/arm/mach-omap2/powerdomain.c | 11 +++++++- arch/arm/plat-omap/include/plat/omap_device.h | 1 + arch/arm/plat-omap/include/plat/powerdomain.h | 2 +- arch/arm/plat-omap/omap_device.c | 29 +++++++++++++++++++++++++ 4 files changed, 40 insertions(+), 3 deletions(-) diff --git a/arch/arm/mach-omap2/powerdomain.c b/arch/arm/mach-omap2/powerdomain.c index 9a0fb38..ac54607 100644 --- a/arch/arm/mach-omap2/powerdomain.c +++ b/arch/arm/mach-omap2/powerdomain.c @@ -145,15 +145,19 @@ static void _update_logic_membank_counters(struct powerdomain *pwrdm) prev_logic_pwrst = pwrdm_read_prev_logic_pwrst(pwrdm); if ((pwrdm->pwrsts_logic_ret == PWRSTS_OFF_RET) && - (prev_logic_pwrst == PWRDM_POWER_OFF)) + (prev_logic_pwrst == PWRDM_POWER_OFF)) { pwrdm->ret_logic_off_counter++; + pwrdm->lost_context = true; + } for (i = 0; i < pwrdm->banks; i++) { prev_mem_pwrst = pwrdm_read_prev_mem_pwrst(pwrdm, i); if ((pwrdm->pwrsts_mem_ret[i] == PWRSTS_OFF_RET) && - (prev_mem_pwrst == PWRDM_POWER_OFF)) + (prev_mem_pwrst == PWRDM_POWER_OFF)) { pwrdm->ret_mem_off_counter[i]++; + pwrdm->lost_context = true; + } } } @@ -176,6 +180,8 @@ static int _pwrdm_state_switch(struct powerdomain *pwrdm, int flag) prev = pwrdm_read_prev_pwrst(pwrdm); if (pwrdm->state != prev) pwrdm->state_counter[prev]++; + if (prev == PWRDM_POWER_OFF) + pwrdm->lost_context = true; if (prev == PWRDM_POWER_RET) _update_logic_membank_counters(pwrdm); break; @@ -197,6 +203,7 @@ static int _pwrdm_pre_transition_cb(struct powerdomain *pwrdm, void *unused) { pwrdm_clear_all_prev_pwrst(pwrdm); _pwrdm_state_switch(pwrdm, PWRDM_STATE_NOW); + pwrdm->lost_context = false; return 0; } diff --git a/arch/arm/plat-omap/include/plat/omap_device.h b/arch/arm/plat-omap/include/plat/omap_device.h index 3694b62..b6ef94c 100644 --- a/arch/arm/plat-omap/include/plat/omap_device.h +++ b/arch/arm/plat-omap/include/plat/omap_device.h @@ -79,6 +79,7 @@ struct omap_device { int omap_device_enable(struct platform_device *pdev); int omap_device_idle(struct platform_device *pdev); int omap_device_shutdown(struct platform_device *pdev); +bool omap_device_has_lost_context(struct platform_device *pdev); /* Core code interface */ diff --git a/arch/arm/plat-omap/include/plat/powerdomain.h b/arch/arm/plat-omap/include/plat/powerdomain.h index d82b2c0..bd5ab48 100644 --- a/arch/arm/plat-omap/include/plat/powerdomain.h +++ b/arch/arm/plat-omap/include/plat/powerdomain.h @@ -102,7 +102,7 @@ struct powerdomain { unsigned state_counter[PWRDM_MAX_PWRSTS]; unsigned ret_logic_off_counter; unsigned ret_mem_off_counter[PWRDM_MAX_MEM_BANKS]; - + bool lost_context; #ifdef CONFIG_PM_DEBUG s64 timer; s64 state_timer[PWRDM_MAX_PWRSTS]; diff --git a/arch/arm/plat-omap/omap_device.c b/arch/arm/plat-omap/omap_device.c index 5904358..0340b40 100644 --- a/arch/arm/plat-omap/omap_device.c +++ b/arch/arm/plat-omap/omap_device.c @@ -84,6 +84,7 @@ #include <plat/omap_device.h> #include <plat/omap_hwmod.h> +#include <plat/powerdomain.h> /* These parameters are passed to _omap_device_{de,}activate() */ #define USE_WAKEUP_LAT 0 @@ -579,6 +580,34 @@ int omap_device_shutdown(struct platform_device *pdev) } /** + * omap_device_has_lost_context() - check if omap_device has lost context + * @od: struct omap_device * + * + * When an omap_device has been deactivated via omap_device_idle() or + * omap_device_shutdown() and then (re)activated using omap_device_enable() + * This function should be used to determine if the omap_device has + * lost context (due to an off-mode transistion) + */ +bool omap_device_has_lost_context(struct platform_device *pdev) +{ + struct omap_device *od; + struct powerdomain *pwrdm; + + od = _find_by_pdev(pdev); + + if (od->_state != OMAP_DEVICE_STATE_ENABLED) { + WARN(1, "omap_device: %s.%d: has_lost_context() called " + "from invalid state\n", od->pdev.name, od->pdev.id); + return -EINVAL; + } + pwrdm = omap_device_get_pwrdm(od); + if (pwrdm) + return pwrdm->lost_context; + + return false; +} + +/** * omap_device_align_pm_lat - activate/deactivate device to match wakeup lat lim * @od: struct omap_device * * -- 1.7.0.2 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
