[PATCH 1/4] exynos4-is: Clear isp-i2c adapter power.ignore_children flag

Sylwester Nawrocki
2016-09-01T11:39:37Z

Since commit 04f59143b571161d25315dd52d7a2ecc022cb71a
("i2c: let I2C masters ignore their children for PM")
the power.ignore_children flag is set when registering an I2C
adapter. Since I2C transfers are not managed by the fimc-isp-i2c
driver its clients use pm_runtime_* calls directly to communicate
required power state of the bus controller.
However when the power.ignore_children flag is set that doesn't
work, so clear that flag back after registering the adapter.
While at it drop pm_runtime_enable() call on the i2c_adapter
as it is already done by the I2C subsystem when registering
I2C adapter.

Cc: <stable@vger.kernel.org> # 4.7+
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
---
drivers/media/platform/exynos4-is/fimc-is-i2c.c | 25 ++++++++++++++++++-------
1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/media/platform/exynos4-is/fimc-is-i2c.c b/drivers/media/platform/exynos4-is/fimc-is-i2c.c
index 7521aa5..03b4246 100644
--- a/drivers/media/platform/exynos4-is/fimc-is-i2c.c
+++ b/drivers/media/platform/exynos4-is/fimc-is-i2c.c
@@ -55,26 +55,37 @@ static int fimc_is_i2c_probe(struct platform_device *pdev)
i2c_adap->algo = &fimc_is_i2c_algorithm;
i2c_adap->class = I2C_CLASS_SPD;

+ platform_set_drvdata(pdev, isp_i2c);
+ pm_runtime_enable(&pdev->dev);
+
ret = i2c_add_adapter(i2c_adap);
if (ret < 0) {
dev_err(&pdev->dev, "failed to add I2C bus %s\n",
node->full_name);
- return ret;
+ goto err_pm_dis;
}

- platform_set_drvdata(pdev, isp_i2c);
-
- pm_runtime_enable(&pdev->dev);
- pm_runtime_enable(&i2c_adap->dev);
-
+ /*
+ * Client drivers of this adapter don't do any I2C transfers as that
+ * is handled by the ISP firmware. But we rely on the runtime PM
+ * state propagation from the clients up to the adapter driver so
+ * clear the ignore_children flags here. PM rutnime calls are not
+ * used in probe() handler of clients of this adapter so there is
+ * no issues with clearing the flag right after registering the I2C
+ * adapter.
+ */
+ pm_suspend_ignore_children(&i2c_adap->dev, false);
return 0;
+
+err_pm_dis:
+ pm_runtime_disable(&pdev->dev);
+ return ret;
}

static int fimc_is_i2c_remove(struct platform_device *pdev)
{
struct fimc_is_i2c *isp_i2c = platform_get_drvdata(pdev);

- pm_runtime_disable(&isp_i2c->adapter.dev);
pm_runtime_disable(&pdev->dev);
i2c_del_adapter(&isp_i2c->adapter);

--
1.9.1