Commit 48fe2cdd authored by Rafael J. Wysocki's avatar Rafael J. Wysocki Committed by Jarkko Sakkinen
Browse files

tpm_crb: Convert ACPI driver to a platform one 

In all cases in which a struct acpi_driver is used for binding a driver
to an ACPI device object, a corresponding platform device is created by
the ACPI core and that device is regarded as a proper representation of
underlying hardware.  Accordingly, a struct platform_driver should be
used by driver code to bind to that device.  There are multiple reasons
why drivers should not bind directly to ACPI device objects [1].

Overall, it is better to bind drivers to platform devices than to their
ACPI companions, so convert the tpm_crb ACPI driver to a platform one.

While this is not expected to alter functionality, it changes sysfs
layout and so it will be visible to user space.

Link: https://lore.kernel.org/all/2396510.ElGaqSPkdT@rafael.j.wysocki/

 [1]
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: default avatarJarkko Sakkinen <jarkko@kernel.org>
parent e6ffe094

drivers/char/tpm/tpm_crb.c

+16 −19
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
#include <linux/highmem.h>

#include <linux/rculist.h>

#include <linux/module.h>

#include <linux/platform_device.h>

#include <linux/pm_runtime.h>

#ifdef CONFIG_ARM64

#include <linux/arm-smccc.h>
@@ -602,13 +603,13 @@ static u64 crb_fixup_cmd_size(struct device *dev, struct resource *io_res, 
	return io_res->end - start + 1;

}



static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,

static int crb_map_io(struct device *dev, struct crb_priv *priv,

		      struct acpi_table_tpm2 *buf)

{

	struct acpi_device *device = ACPI_COMPANION(dev);

	struct list_head acpi_resource_list;

	struct resource iores_array[TPM_CRB_MAX_RESOURCES + 1] = { {0} };

	void __iomem *iobase_array[TPM_CRB_MAX_RESOURCES] = {NULL};

	struct device *dev = &device->dev;

	struct resource *iores;

	void __iomem **iobase_ptr;

	int i;
@@ -782,12 +783,13 @@ static int crb_map_pluton(struct device *dev, struct crb_priv *priv, 
	return 0;

}



static int crb_acpi_add(struct acpi_device *device)

static int crb_acpi_probe(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct acpi_device *device = ACPI_COMPANION(dev);

	struct acpi_table_tpm2 *buf;

	struct crb_priv *priv;

	struct tpm_chip *chip;

	struct device *dev = &device->dev;

	struct tpm2_crb_smc *crb_smc;

	struct tpm2_crb_ffa *crb_ffa;

	struct tpm2_crb_pluton *crb_pluton;
@@ -867,7 +869,7 @@ static int crb_acpi_add(struct acpi_device *device) 
	priv->sm = sm;

	priv->hid = acpi_device_hid(device);



	rc = crb_map_io(device, priv, buf);

	rc = crb_map_io(dev, priv, buf);

	if (rc)

		goto out;
@@ -901,12 +903,9 @@ static int crb_acpi_add(struct acpi_device *device) 
	return rc;

}



static void crb_acpi_remove(struct acpi_device *device)

static void crb_acpi_remove(struct platform_device *pdev)

{

	struct device *dev = &device->dev;

	struct tpm_chip *chip = dev_get_drvdata(dev);



	tpm_chip_unregister(chip);

	tpm_chip_unregister(platform_get_drvdata(pdev));

}



static const struct dev_pm_ops crb_pm = {
@@ -919,19 +918,17 @@ static const struct acpi_device_id crb_device_ids[] = { 
};

MODULE_DEVICE_TABLE(acpi, crb_device_ids);



static struct acpi_driver crb_acpi_driver = {

	.name = "tpm_crb",

	.ids = crb_device_ids,

	.ops = {

		.add = crb_acpi_add,

static struct platform_driver crb_acpi_driver = {

	.probe = crb_acpi_probe,

	.remove = crb_acpi_remove,

	},

	.drv = {

	.driver = {

		.name = "tpm_crb_acpi",

		.acpi_match_table = crb_device_ids,

		.pm = &crb_pm,

	},

};



module_acpi_driver(crb_acpi_driver);

module_platform_driver(crb_acpi_driver);

MODULE_AUTHOR("Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>");

MODULE_DESCRIPTION("TPM2 Driver");

MODULE_VERSION("0.1");