[PATCH 05/13] memory: mtk-smi: Add device-link between smi-larb and smi-common

From: Yong Wu
Date: Mon Dec 31 2018 - 23:52:32 EST


Normally, If the smi-larb HW need work, we should enable the smi-common
HW power and clock firstly.
This patch adds device-link between the smi-larb dev and the smi-common
dev. then If pm_runtime_get_sync(smi-larb-dev), the pm_runtime_get_sync
(smi-common-dev) will be called automatically.

Since smi is built-in driver like IOMMU and never unbound,
DL_FLAG_AUTOREMOVE_* is not needed.

CC: Matthias Brugger <matthias.bgg@xxxxxxxxx>
Suggested-by: Tomasz Figa <tfiga@xxxxxxxxxxxx>
Signed-off-by: Yong Wu <yong.wu@xxxxxxxxxxxx>
---
drivers/memory/mtk-smi.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c
index 9688341..30930e4 100644
--- a/drivers/memory/mtk-smi.c
+++ b/drivers/memory/mtk-smi.c
@@ -271,6 +271,7 @@ static int mtk_smi_larb_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct device_node *smi_node;
struct platform_device *smi_pdev;
+ struct device_link *link;

larb = devm_kzalloc(dev, sizeof(*larb), GFP_KERNEL);
if (!larb)
@@ -310,6 +311,12 @@ static int mtk_smi_larb_probe(struct platform_device *pdev)
if (!platform_get_drvdata(smi_pdev))
return -EPROBE_DEFER;
larb->smi_common_dev = &smi_pdev->dev;
+ link = device_link_add(dev, larb->smi_common_dev,
+ DL_FLAG_PM_RUNTIME);
+ if (!link) {
+ dev_err(dev, "Unable to link smi-common dev\n");
+ return -ENODEV;
+ }
} else {
dev_err(dev, "Failed to get the smi_common device\n");
return -EINVAL;
@@ -333,17 +340,9 @@ static int __maybe_unused mtk_smi_larb_resume(struct device *dev)
const struct mtk_smi_larb_gen *larb_gen = larb->larb_gen;
int ret;

- /* Power on smi-common. */
- ret = pm_runtime_get_sync(larb->smi_common_dev);
- if (ret < 0) {
- dev_err(dev, "Failed to pm get for smi-common(%d).\n", ret);
- return ret;
- }
-
ret = mtk_smi_clk_enable(&larb->smi);
if (ret < 0) {
dev_err(dev, "Failed to enable clock(%d).\n", ret);
- pm_runtime_put_sync(larb->smi_common_dev);
return ret;
}

@@ -358,7 +357,6 @@ static int __maybe_unused mtk_smi_larb_suspend(struct device *dev)
struct mtk_smi_larb *larb = dev_get_drvdata(dev);

mtk_smi_clk_disable(&larb->smi);
- pm_runtime_put_sync(larb->smi_common_dev);
return 0;
}

--
1.9.1