diff mbox series

[RFC,v5,01/14] i2c: tegra: Don't mark VI I2C as IRQ safe runtime PM

Message ID 1595883452-17343-2-git-send-email-skomatineni@nvidia.com
State Changes Requested
Headers show
Series Support for Tegra video capture from external sensor | expand

Commit Message

Sowjanya Komatineni July 27, 2020, 8:57 p.m. UTC 
Tegra VI I2C is part of VE power domain and typically used for
camera usecases.

VE power domain is not always on and is non-IRQ safe. So, IRQ safe
device cannot be attached to a non-IRQ safe domain as it prevents
powering off the PM domain and generic power domain driver will warn.

Current driver marks all I2C devices as IRQ safe and VI I2C device
does not require IRQ safe as it will not be used for atomic transfers.

This patch has fix to make VI I2C as non-IRQ safe.

Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/i2c/busses/i2c-tegra.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

Comments

Wolfram Sang July 28, 2020, 4:33 p.m. UTC | #1 
On Mon, Jul 27, 2020 at 01:57:19PM -0700, Sowjanya Komatineni wrote:
> Tegra VI I2C is part of VE power domain and typically used for
> camera usecases.
> 
> VE power domain is not always on and is non-IRQ safe. So, IRQ safe
> device cannot be attached to a non-IRQ safe domain as it prevents
> powering off the PM domain and generic power domain driver will warn.
> 
> Current driver marks all I2C devices as IRQ safe and VI I2C device
> does not require IRQ safe as it will not be used for atomic transfers.
> 
> This patch has fix to make VI I2C as non-IRQ safe.
> 
> Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
> Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>

Applied to for-next, thanks!
diff mbox series

Patch

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 1577296..3be1018 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -1750,7 +1750,15 @@  static int tegra_i2c_probe(struct platform_device *pdev)
 		goto unprepare_slow_clk;
 	}
 
-	pm_runtime_irq_safe(&pdev->dev);
+	/*
+	 * VI I2C is in VE power domain which is not always on and not
+	 * an IRQ safe. So, IRQ safe device can't be attached to a non-IRQ
+	 * safe domain as it prevents powering off the PM domain.
+	 * Also, VI I2C device don't need to use runtime IRQ safe as it will
+	 * not be used for atomic transfers.
+	 */
+	if (!i2c_dev->is_vi)
+		pm_runtime_irq_safe(&pdev->dev);
 	pm_runtime_enable(&pdev->dev);
 	if (!pm_runtime_enabled(&pdev->dev)) {
 		ret = tegra_i2c_runtime_resume(&pdev->dev);