[PATCH v9] ARM: omap: edma: add suspend resume hook
From: Sekhar Nori <hidden>
Date: 2014-11-14 17:03:23
Also in:
linux-omap
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
On Tuesday 26 August 2014 02:22 PM, Daniel Mack wrote:
quoted hunk ↗ jump to hunk
This patch makes the edma driver resume correctly after suspend. Tested on an AM33xx platform with cyclic audio streams and omap_hsmmc. All information can be reconstructed by already known runtime information. As we now use some functions that were previously only used from __init context, annotations had to be dropped. [nm at ti.com: added error handling for runtime + suspend_late/early_resume] Signed-off-by: Nishanth Menon <nm@ti.com> Signed-off-by: Daniel Mack <zonque@gmail.com> Tested-by: Joel Fernandes <redacted> Acked-by: Joel Fernandes <redacted> --- Changes from v8: * Drop the edma_suspend hook altogether. Even though back then when I wrote the code I was sure disabling the interrupts during suspend is necessary, tests now show it in fact isn't. My test setup still works if that code is omitted. * Use SET_LATE_SYSTEM_SLEEP_PM_OPS in the dev_pm_ops declaration. Thanks to Sekhar for pointing out the above. arch/arm/common/edma.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 58 insertions(+), 2 deletions(-)diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c index 485be42..c623dd0 100644 --- a/arch/arm/common/edma.c +++ b/arch/arm/common/edma.c@@ -244,6 +244,8 @@ struct edma { /* list of channels with no even trigger; terminated by "-1" */ const s8 *noevent; + struct edma_soc_info *info; + /* The edma_inuse bit for each PaRAM slot is clear unless the * channel is in use ... by ARM or DSP, for QDMA, or whatever. */@@ -295,7 +297,7 @@ static void map_dmach_queue(unsigned ctlr, unsigned ch_no, ~(0x7 << bit), queue_no << bit); } -static void __init assign_priority_to_queue(unsigned ctlr, int queue_no, +static void assign_priority_to_queue(unsigned ctlr, int queue_no, int priority) { int bit = queue_no * 4;@@ -314,7 +316,7 @@ static void __init assign_priority_to_queue(unsigned ctlr, int queue_no, * included in that particular EDMA variant (Eg : dm646x) * */ -static void __init map_dmach_param(unsigned ctlr) +static void map_dmach_param(unsigned ctlr) { int i; for (i = 0; i < EDMA_MAX_DMACH; i++)@@ -1762,15 +1764,69 @@ static int edma_probe(struct platform_device *pdev) edma_write_array2(j, EDMA_DRAE, i, 1, 0x0); edma_write_array(j, EDMA_QRAE, i, 0x0); } + edma_cc[j]->info = info[j]; arch_num_cc++; } return 0; } +static int edma_pm_resume(struct device *dev) +{ + int i, j, r; + + r = pm_runtime_get_sync(dev);
I think I have asked this before, and I am still not sure why this call to pm_runtime_get_sync() is needed here. From my testing today, this does seem to be a a no-op and this call returns from rpm_resume() because of this check: else if (dev->power.disable_depth == 1 && dev->power.is_suspended && dev->power.runtime_status == RPM_ACTIVE) retval = 1; So, AFAICS, the net effect is an increment of dev->power.usage_count (which is already greater than 0) and its subsequent decrement at the end of the function. After removing this call I did not see any EDMA malfunction as well (can access MMC/SD just fine after suspend/resume cycle). So, any objections to merging this patch with the attached hunk applied? Thanks, Sekhar ---8<---
diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
index 1f492d5be9c0..79de6a23047b 100644
--- a/arch/arm/common/edma.c
+++ b/arch/arm/common/edma.c@@ -1803,13 +1803,7 @@ static int edma_probe(struct platform_device *pdev) static int edma_pm_resume(struct device *dev) { - int i, j, r; - - r = pm_runtime_get_sync(dev); - if (r < 0) { - dev_err(dev, "%s: get_sync returned %d\n", __func__, r); - return r; - } + int i, j; for (j = 0; j < arch_num_cc; j++) { struct edma *cc = edma_cc[j];
@@ -1844,8 +1838,6 @@ static int edma_pm_resume(struct device *dev) } } - pm_runtime_put_sync(dev); - return 0; }