[PATCH 1 0/4] PCI: Use of_device_get_match_data() to simplify probe

This turned into much ado about nothing, but Shailendra's hisi patch
prompted similar cleanups in other drivers.  It's a minor simplification,
but I think worth doing consistently across drivers.

Basically this is Geert's observation that when the driver probe function
is called only as a result of matching something in <match_table>, a
subsequent of_match_device(<match_table>, dev) call should never fail.

Therefore, instead of this:

  struct of_device_id *match;

  match = of_match_device(<match_table>, dev);
  ... = match->data;

we can do this:

  ... = of_device_get_match_data(dev);

---

Bjorn Helgaas (3):
      PCI: iproc: Use of_device_get_match_data() to simplify probe
      PCI: layerscape: Use of_device_get_match_data() to simplify probe
      PCI: rcar: Use of_device_get_match_data() to simplify probe

Shailendra Verma (1):
      PCI: hisi: Use of_device_get_match_data() to simplify probe


 drivers/pci/host/pci-layerscape.c      |    7 +------
 drivers/pci/host/pcie-hisi.c           |    8 +++-----
 drivers/pci/host/pcie-iproc-platform.c |    7 +------
 drivers/pci/host/pcie-rcar.c           |    7 +------
 4 files changed, 6 insertions(+), 23 deletions(-)

From: Shailendra Verma <redacted>

The only way to call hisi_pcie_probe() is to match an entry in
hisi_pcie_of_match[], so match cannot be NULL.

Use of_device_get_match_data() to retrieve the soc_ops pointer.  No
functional change intended.

[bhelgaas: use of_device_get_match_data(), changelog]
Based-on-suggestion-from: Geert Uytterhoeven [off-list ref]
Signed-off-by: Shailendra Verma <redacted>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/pci/host/pcie-hisi.c |    8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/pci/host/pcie-hisi.c b/drivers/pci/host/pcie-hisi.c
index a301a7187b30..33c201afdbf1 100644
--- a/drivers/pci/host/pcie-hisi.c
+++ b/drivers/pci/host/pcie-hisi.c

@@ -139,7 +139,7 @@ struct hisi_pcie {
 	struct pcie_port pp;		/* pp.dbi_base is DT rc_dbi */
 	struct regmap *subctrl;
 	u32 port_id;
-	struct pcie_soc_ops *soc_ops;
+	const struct pcie_soc_ops *soc_ops;
 };
 
 /* HipXX PCIe host only supports 32-bit config access */

@@ -259,7 +259,6 @@ static int hisi_pcie_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct hisi_pcie *hisi_pcie;
 	struct pcie_port *pp;
-	const struct of_device_id *match;
 	struct resource *reg;
 	struct device_driver *driver;
 	int ret;

@@ -272,11 +271,10 @@ static int hisi_pcie_probe(struct platform_device *pdev)
 	pp->dev = dev;
 	driver = dev->driver;
 
-	match = of_match_device(driver->of_match_table, dev);
-	hisi_pcie->soc_ops = (struct pcie_soc_ops *) match->data;
+	hisi_pcie->soc_ops = of_device_get_match_data(dev);
 
 	hisi_pcie->subctrl =
-	syscon_regmap_lookup_by_compatible("hisilicon,pcie-sas-subctrl");
+	    syscon_regmap_lookup_by_compatible("hisilicon,pcie-sas-subctrl");
 	if (IS_ERR(hisi_pcie->subctrl)) {
 		dev_err(dev, "cannot get subctrl base\n");
 		return PTR_ERR(hisi_pcie->subctrl);

The only way to call iproc_pcie_pltfm_probe() is to match an entry in
iproc_pcie_of_match_table[], so match cannot be NULL.

Use of_device_get_match_data() to retrieve the pcie->type.  No functional
change intended.

Based-on-suggestion-from: Geert Uytterhoeven [off-list ref]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/pci/host/pcie-iproc-platform.c |    7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/pci/host/pcie-iproc-platform.c b/drivers/pci/host/pcie-iproc-platform.c
index 22d814a78a78..f4909bb0b2ad 100644
--- a/drivers/pci/host/pcie-iproc-platform.c
+++ b/drivers/pci/host/pcie-iproc-platform.c

@@ -47,7 +47,6 @@ MODULE_DEVICE_TABLE(of, iproc_pcie_of_match_table);
 static int iproc_pcie_pltfm_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	const struct of_device_id *of_id;
 	struct iproc_pcie *pcie;
 	struct device_node *np = dev->of_node;
 	struct resource reg;

@@ -55,16 +54,12 @@ static int iproc_pcie_pltfm_probe(struct platform_device *pdev)
 	LIST_HEAD(res);
 	int ret;
 
-	of_id = of_match_device(iproc_pcie_of_match_table, dev);
-	if (!of_id)
-		return -EINVAL;
-
 	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
 	if (!pcie)
 		return -ENOMEM;
 
 	pcie->dev = dev;
-	pcie->type = (enum iproc_pcie_type)of_id->data;
+	pcie->type = (enum iproc_pcie_type) of_device_get_match_data(dev);
 
 	ret = of_address_to_resource(np, 0, &reg);
 	if (ret < 0) {

The only way to call ls_pcie_probe() is to match an entry in
ls_pcie_of_match[], so match cannot be NULL.

Use of_device_get_match_data() to retrieve the drvdata pointer.  No
functional change intended.

Based-on-suggestion-from: Geert Uytterhoeven [off-list ref]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/pci/host/pci-layerscape.c |    7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/pci/host/pci-layerscape.c b/drivers/pci/host/pci-layerscape.c
index ea789138531b..c1f06f8f05fd 100644
--- a/drivers/pci/host/pci-layerscape.c
+++ b/drivers/pci/host/pci-layerscape.c

@@ -239,23 +239,18 @@ static int __init ls_add_pcie_port(struct ls_pcie *pcie)
 static int __init ls_pcie_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
-	const struct of_device_id *match;
 	struct ls_pcie *pcie;
 	struct pcie_port *pp;
 	struct resource *dbi_base;
 	int ret;
 
-	match = of_match_device(ls_pcie_of_match, dev);
-	if (!match)
-		return -ENODEV;
-
 	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
 	if (!pcie)
 		return -ENOMEM;
 
 	pp = &pcie->pp;
 	pp->dev = dev;
-	pcie->drvdata = match->data;
+	pcie->drvdata = of_device_get_match_data(dev);
 	pp->ops = pcie->drvdata->ops;
 
 	dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "regs");

This is a DT-only driver, so the only way to call rcar_pcie_probe() is to
match an entry in rcar_pcie_of_match[], so of_id cannot be NULL.

Furthermore, of_id->data can only be NULL if an rcar_pcie_of_match[] entry
has a NULL .data member.  That's a driver defect, and we don't want to
return -EINVAL, which is easy to ignore.  We'd rather take the NULL pointer
dereference so we notice the problem and fix it.

Use of_device_get_match_data() to retrieve the hw_init_fn pointer.  No
functional change intended.

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
 drivers/pci/host/pcie-rcar.c |    7 +------
 1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
index aca85be101f8..b3b6d5273347 100644
--- a/drivers/pci/host/pcie-rcar.c
+++ b/drivers/pci/host/pcie-rcar.c

@@ -1125,7 +1125,6 @@ static int rcar_pcie_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	struct rcar_pcie *pcie;
 	unsigned int data;
-	const struct of_device_id *of_id;
 	int err;
 	int (*hw_init_fn)(struct rcar_pcie *);
 

@@ -1149,11 +1148,6 @@ static int rcar_pcie_probe(struct platform_device *pdev)
 	if (err)
 		return err;
 
-	of_id = of_match_device(rcar_pcie_of_match, dev);
-	if (!of_id || !of_id->data)
-		return -EINVAL;
-	hw_init_fn = of_id->data;
-
 	pm_runtime_enable(dev);
 	err = pm_runtime_get_sync(dev);
 	if (err < 0) {

@@ -1162,6 +1156,7 @@ static int rcar_pcie_probe(struct platform_device *pdev)
 	}
 
 	/* Failure to get a link might just be that no cards are inserted */
+	hw_init_fn = of_device_get_match_data(dev);
 	err = hw_init_fn(pcie);
 	if (err) {
 		dev_info(dev, "PCIe link down\n");

On Tue, Jan 31, 2017 at 02:20:20PM -0600, Bjorn Helgaas wrote:

This is a DT-only driver, so the only way to call rcar_pcie_probe() is to
match an entry in rcar_pcie_of_match[], so of_id cannot be NULL.

Furthermore, of_id->data can only be NULL if an rcar_pcie_of_match[] entry
has a NULL .data member.  That's a driver defect, and we don't want to
return -EINVAL, which is easy to ignore.  We'd rather take the NULL pointer
dereference so we notice the problem and fix it.

Use of_device_get_match_data() to retrieve the hw_init_fn pointer.  No
functional change intended.

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

Acked-by: Simon Horman <redacted>

On Tue, Jan 31, 2017 at 02:19:51PM -0600, Bjorn Helgaas wrote:

This turned into much ado about nothing, but Shailendra's hisi patch
prompted similar cleanups in other drivers.  It's a minor simplification,
but I think worth doing consistently across drivers.

Basically this is Geert's observation that when the driver probe function
is called only as a result of matching something in <match_table>, a
subsequent of_match_device(<match_table>, dev) call should never fail.

Therefore, instead of this:

  struct of_device_id *match;

  match = of_match_device(<match_table>, dev);
  ... = match->data;

we can do this:

  ... = of_device_get_match_data(dev);

---

Bjorn Helgaas (3):
      PCI: iproc: Use of_device_get_match_data() to simplify probe
      PCI: layerscape: Use of_device_get_match_data() to simplify probe
      PCI: rcar: Use of_device_get_match_data() to simplify probe

Shailendra Verma (1):
      PCI: hisi: Use of_device_get_match_data() to simplify probe


 drivers/pci/host/pci-layerscape.c      |    7 +------
 drivers/pci/host/pcie-hisi.c           |    8 +++-----
 drivers/pci/host/pcie-iproc-platform.c |    7 +------
 drivers/pci/host/pcie-rcar.c           |    7 +------
 4 files changed, 6 insertions(+), 23 deletions(-)

I applied these to pci/host-layerscape, pci/host-hisi, pci/host-iproc,
pci/host-rcar for v4.11.