[PATCH 3/7] spi: omap2-mcspi: Fix PM regression with deferred probe for pm_runtime_reinit
From: Ulf Hansson <hidden>
Date: 2016-02-12 12:51:18
Also in:
linux-i2c, linux-mmc, linux-omap, linux-serial, linux-spi
On 11 February 2016 at 00:02, Tony Lindgren [off-list ref] wrote:
Commit 5de85b9d57ab ("PM / runtime: Re-init runtime PM states at probe
error and driver unbind") introduced pm_runtime_reinit() that is used
to reinitialize PM runtime after -EPROBE_DEFER. This allows shutting
down the device after a failed probe.
However, for drivers using pm_runtime_use_autosuspend() this can cause
a state where suspend callback is never called after -EPROBE_DEFER.
On the following device driver probe, hardware state is different from
the PM runtime state causing omap_device to produce the following
error:
omap_device_enable() called from invalid state 1
And with omap_device and omap hardware being picky for PM, this will
block any deeper idle states in hardware.
The solution is to fix the drivers to follow the PM runtime documentation:
1. For sections of code that needs the device disabled, use
pm_runtime_put_sync_suspend() if pm_runtime_set_autosuspend() has
been set.
2. For driver exit code, use pm_runtime_dont_use_autosuspend() before
pm_runtime_put_sync() if pm_runtime_use_autosuspend() has been
set.
Fixes: 5de85b9d57ab ("PM / runtime: Re-init runtime PM states at probe
error and driver unbind")
Cc: linux-spi at vger.kernel.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: Mark Brown <broonie@kernel.org>
Cc: Nishanth Menon <nm@ti.com>
Cc: Rafael J. Wysocki <rafael@kernel.org>
Cc: Ulf Hansson <redacted>
Cc: Tero Kristo <redacted>
Signed-off-by: Tony Lindgren <tony@atomide.com>Acked-by: Ulf Hansson <redacted> Kind regards Uffe
quoted hunk ↗ jump to hunk
--- Mark, I'd like to merge this along with other related fixes via the ARM SoC tree if no objections, please review and ack if this look OK to you. --- drivers/spi/spi-omap2-mcspi.c | 3 +++ 1 file changed, 3 insertions(+)diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 7273820..0caa3c8 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c@@ -1490,6 +1490,8 @@ static int omap2_mcspi_probe(struct platform_device *pdev) return status; disable_pm: + pm_runtime_dont_use_autosuspend(&pdev->dev); + pm_runtime_put_sync(&pdev->dev); pm_runtime_disable(&pdev->dev); free_master: spi_master_put(master);@@ -1501,6 +1503,7 @@ static int omap2_mcspi_remove(struct platform_device *pdev) struct spi_master *master = platform_get_drvdata(pdev); struct omap2_mcspi *mcspi = spi_master_get_devdata(master); + pm_runtime_dont_use_autosuspend(mcspi->dev); pm_runtime_put_sync(mcspi->dev); pm_runtime_disable(&pdev->dev); --2.7.0