diff mbox series

[v3,03/10] mfd: cs5535-mfd: Request shared IO regions centrally

Message ID 20191024163832.31326-4-lee.jones@linaro.org
State Superseded
Headers show
Series Simplify MFD Core | expand

Commit Message

Lee Jones Oct. 24, 2019, 4:38 p.m. UTC
Prior to this patch, IO regions were requested via an MFD subsytem-level
.enable() call-back and similarly released by a .disable() call-back.
Double requests/releases were avoided by a centrally handled usage count
mechanism.

This complexity can all be avoided by handling IO regions only once during
.probe() and .remove() of the parent device.  Since this is the only
legitimate user of the aforementioned usage count mechanism, this patch
will allow it to be removed from MFD core in subsequent steps.

Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

---
 drivers/mfd/cs5535-mfd.c | 71 +++++++++++++++++-----------------------
 1 file changed, 30 insertions(+), 41 deletions(-)

-- 
2.17.1

Comments

Daniel Thompson Oct. 25, 2019, 8:50 a.m. UTC | #1
On Thu, Oct 24, 2019 at 05:38:25PM +0100, Lee Jones wrote:
> Prior to this patch, IO regions were requested via an MFD subsytem-level

> .enable() call-back and similarly released by a .disable() call-back.

> Double requests/releases were avoided by a centrally handled usage count

> mechanism.

> 

> This complexity can all be avoided by handling IO regions only once during

> .probe() and .remove() of the parent device.  Since this is the only

> legitimate user of the aforementioned usage count mechanism, this patch

> will allow it to be removed from MFD core in subsequent steps.

> 

> Suggested-by: Daniel Thompson <daniel.thompson@linaro.org>

> Signed-off-by: Lee Jones <lee.jones@linaro.org>

> ---

>  drivers/mfd/cs5535-mfd.c | 71 +++++++++++++++++-----------------------

>  1 file changed, 30 insertions(+), 41 deletions(-)

> 

> diff --git a/drivers/mfd/cs5535-mfd.c b/drivers/mfd/cs5535-mfd.c

> index b35f1efa01f6..27fa8fa1ec9b 100644

> --- a/drivers/mfd/cs5535-mfd.c

> +++ b/drivers/mfd/cs5535-mfd.c

> @@ -27,38 +27,6 @@ enum cs5535_mfd_bars {

>  	NR_BARS,

>  };

>  

> -static int cs5535_mfd_res_enable(struct platform_device *pdev)

> -{

> -	struct resource *res;

> -

> -	res = platform_get_resource(pdev, IORESOURCE_IO, 0);

> -	if (!res) {

> -		dev_err(&pdev->dev, "can't fetch device resource info\n");

> -		return -EIO;

> -	}

> -

> -	if (!request_region(res->start, resource_size(res), DRV_NAME)) {

> -		dev_err(&pdev->dev, "can't request region\n");

> -		return -EIO;

> -	}

> -

> -	return 0;

> -}

> -

> -static int cs5535_mfd_res_disable(struct platform_device *pdev)

> -{

> -	struct resource *res;

> -

> -	res = platform_get_resource(pdev, IORESOURCE_IO, 0);

> -	if (!res) {

> -		dev_err(&pdev->dev, "can't fetch device resource info\n");

> -		return -EIO;

> -	}

> -

> -	release_region(res->start, resource_size(res));

> -	return 0;

> -}

> -

>  static struct resource cs5535_mfd_resources[NR_BARS];

>  

>  static struct mfd_cell cs5535_mfd_cells[] = {

> @@ -81,17 +49,11 @@ static struct mfd_cell cs5535_mfd_cells[] = {

>  		.name = "cs5535-pms",

>  		.num_resources = 1,

>  		.resources = &cs5535_mfd_resources[PMS_BAR],

> -

> -		.enable = cs5535_mfd_res_enable,

> -		.disable = cs5535_mfd_res_disable,

>  	},

>  	{

>  		.name = "cs5535-acpi",

>  		.num_resources = 1,

>  		.resources = &cs5535_mfd_resources[ACPI_BAR],

> -

> -		.enable = cs5535_mfd_res_enable,

> -		.disable = cs5535_mfd_res_disable,

>  	},

>  };

>  

> @@ -117,22 +79,47 @@ static int cs5535_mfd_probe(struct pci_dev *pdev,

>  		r->end = pci_resource_end(pdev, bar);

>  	}

>  

> +	err = pci_request_region(pdev, PMS_BAR, DRV_NAME);

> +	if (err) {

> +		dev_err(&pdev->dev, "Failed to request PMS_BAR's IO region\n");

> +		goto err_disable;

> +	}

> +

>  	err = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE, cs5535_mfd_cells,

>  			      ARRAY_SIZE(cs5535_mfd_cells), NULL, 0, NULL);

>  	if (err) {

>  		dev_err(&pdev->dev,

>  			"Failed to add CS5535 sub-devices: %d\n", err);

> -		goto err_disable;

> +		goto err_release_pms;

>  	}

>  

> -	if (machine_is_olpc())

> -		mfd_clone_cell("cs5535-acpi", olpc_acpi_clones, ARRAY_SIZE(olpc_acpi_clones));

> +	if (machine_is_olpc()) {

> +		err = pci_request_region(pdev, ACPI_BAR, DRV_NAME);

> +		if (err) {

> +			dev_err(&pdev->dev,

> +				"Failed to request ACPI_BAR's IO region\n");

> +			goto err_remove_devices;

> +		}


I agree cs5535-acpi isn't used is the kernel but I think it stills
fails a w.t.f. per minute test to have a mismatch between when
a device is added and when it requests resources.

Especially since I don't think this is transient within the patch
series.


> +

> +		err = mfd_clone_cell("cs5535-acpi", olpc_acpi_clones,

> +				     ARRAY_SIZE(olpc_acpi_clones));

> +		if (err) {

> +			dev_err(&pdev->dev, "Failed to clone MFD cell\n");

> +			goto err_release_acpi;

> +		}

> +	}

>  

>  	dev_info(&pdev->dev, "%zu devices registered.\n",

>  			ARRAY_SIZE(cs5535_mfd_cells));

>  

>  	return 0;

>  

> +err_release_acpi:

> +	pci_release_region(pdev, ACPI_BAR);

> +err_remove_devices:

> +	mfd_remove_devices(&pdev->dev);

> +err_release_pms:

> +	pci_release_region(pdev, PMS_BAR);

>  err_disable:

>  	pci_disable_device(pdev);

>  	return err;

> @@ -141,6 +128,8 @@ static int cs5535_mfd_probe(struct pci_dev *pdev,

>  static void cs5535_mfd_remove(struct pci_dev *pdev)

>  {

>  	mfd_remove_devices(&pdev->dev);

> +	pci_release_region(pdev, ACPI_BAR);


This will issue a warning if !machine_is_olpc() .

For the release region family of calls "the described resource region
must match a currently busy region."


Daniel.
diff mbox series

Patch

diff --git a/drivers/mfd/cs5535-mfd.c b/drivers/mfd/cs5535-mfd.c
index b35f1efa01f6..27fa8fa1ec9b 100644
--- a/drivers/mfd/cs5535-mfd.c
+++ b/drivers/mfd/cs5535-mfd.c
@@ -27,38 +27,6 @@  enum cs5535_mfd_bars {
 	NR_BARS,
 };
 
-static int cs5535_mfd_res_enable(struct platform_device *pdev)
-{
-	struct resource *res;
-
-	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
-	if (!res) {
-		dev_err(&pdev->dev, "can't fetch device resource info\n");
-		return -EIO;
-	}
-
-	if (!request_region(res->start, resource_size(res), DRV_NAME)) {
-		dev_err(&pdev->dev, "can't request region\n");
-		return -EIO;
-	}
-
-	return 0;
-}
-
-static int cs5535_mfd_res_disable(struct platform_device *pdev)
-{
-	struct resource *res;
-
-	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
-	if (!res) {
-		dev_err(&pdev->dev, "can't fetch device resource info\n");
-		return -EIO;
-	}
-
-	release_region(res->start, resource_size(res));
-	return 0;
-}
-
 static struct resource cs5535_mfd_resources[NR_BARS];
 
 static struct mfd_cell cs5535_mfd_cells[] = {
@@ -81,17 +49,11 @@  static struct mfd_cell cs5535_mfd_cells[] = {
 		.name = "cs5535-pms",
 		.num_resources = 1,
 		.resources = &cs5535_mfd_resources[PMS_BAR],
-
-		.enable = cs5535_mfd_res_enable,
-		.disable = cs5535_mfd_res_disable,
 	},
 	{
 		.name = "cs5535-acpi",
 		.num_resources = 1,
 		.resources = &cs5535_mfd_resources[ACPI_BAR],
-
-		.enable = cs5535_mfd_res_enable,
-		.disable = cs5535_mfd_res_disable,
 	},
 };
 
@@ -117,22 +79,47 @@  static int cs5535_mfd_probe(struct pci_dev *pdev,
 		r->end = pci_resource_end(pdev, bar);
 	}
 
+	err = pci_request_region(pdev, PMS_BAR, DRV_NAME);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to request PMS_BAR's IO region\n");
+		goto err_disable;
+	}
+
 	err = mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE, cs5535_mfd_cells,
 			      ARRAY_SIZE(cs5535_mfd_cells), NULL, 0, NULL);
 	if (err) {
 		dev_err(&pdev->dev,
 			"Failed to add CS5535 sub-devices: %d\n", err);
-		goto err_disable;
+		goto err_release_pms;
 	}
 
-	if (machine_is_olpc())
-		mfd_clone_cell("cs5535-acpi", olpc_acpi_clones, ARRAY_SIZE(olpc_acpi_clones));
+	if (machine_is_olpc()) {
+		err = pci_request_region(pdev, ACPI_BAR, DRV_NAME);
+		if (err) {
+			dev_err(&pdev->dev,
+				"Failed to request ACPI_BAR's IO region\n");
+			goto err_remove_devices;
+		}
+
+		err = mfd_clone_cell("cs5535-acpi", olpc_acpi_clones,
+				     ARRAY_SIZE(olpc_acpi_clones));
+		if (err) {
+			dev_err(&pdev->dev, "Failed to clone MFD cell\n");
+			goto err_release_acpi;
+		}
+	}
 
 	dev_info(&pdev->dev, "%zu devices registered.\n",
 			ARRAY_SIZE(cs5535_mfd_cells));
 
 	return 0;
 
+err_release_acpi:
+	pci_release_region(pdev, ACPI_BAR);
+err_remove_devices:
+	mfd_remove_devices(&pdev->dev);
+err_release_pms:
+	pci_release_region(pdev, PMS_BAR);
 err_disable:
 	pci_disable_device(pdev);
 	return err;
@@ -141,6 +128,8 @@  static int cs5535_mfd_probe(struct pci_dev *pdev,
 static void cs5535_mfd_remove(struct pci_dev *pdev)
 {
 	mfd_remove_devices(&pdev->dev);
+	pci_release_region(pdev, ACPI_BAR);
+	pci_release_region(pdev, PMS_BAR);
 	pci_disable_device(pdev);
 }