[RFC PATCH v4 01/14] i2c: tegra: Don't mark VI I2C as IRQ safe runtime PM
From: Sowjanya Komatineni <skomatineni@nvidia.com>
Date: 2020-07-23 23:49:27
Also in:
linux-i2c, linux-media, linux-tegra, lkml
Subsystem:
i2c subsystem, i2c subsystem host drivers, tegra i2c driver, the rest · Maintainers:
Wolfram Sang, Andi Shyti, Laxman Dewangan, Linus Torvalds
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. Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com> --- drivers/i2c/busses/i2c-tegra.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
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);
--
2.7.4