Commit 72c77b7e authored by Lv Zheng's avatar Lv Zheng Committed by Rafael J. Wysocki
Browse files

ACPI / EC: Cleanup first_ec/boot_ec code 

In order to support full ECDT (driving the ECDT EC after probing the
namespace EC), we need to change our EC device alloc/free algorithm, ensure
not to free old boot EC before qualifying new boot EC.
This patch achieves this by cleaning up first_ec/boot_ec logic:
1. first_ec: used to perform transactions, so it is assigned in new
   acpi_ec_setup() function.
2. boot_ec: used to track early EC device, so it is assigned in new
   acpi_config_boot_ec() function which explictly tells the driver to save
   the EC device as early EC device.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=115021


Reported-and-tested-by: default avatarLuya Tshimbalanga <luya@fedoraproject.org>
Tested-by: default avatarJonh Henderson <jw.hendy@gmail.com>
Signed-off-by: default avatarLv Zheng <lv.zheng@intel.com>
Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
parent d3028305

drivers/acpi/ec.c

+63 −33
Original line number Diff line number Diff line
@@ -184,6 +184,7 @@ static void acpi_ec_event_processor(struct work_struct *work); 


struct acpi_ec *boot_ec, *first_ec;

EXPORT_SYMBOL(first_ec);

static bool boot_ec_is_ecdt = false;

static struct workqueue_struct *ec_query_wq;



static int EC_FLAGS_CLEAR_ON_RESUME; /* Needs acpi_ec_clear() on boot/resume */
@@ -1304,7 +1305,16 @@ acpi_ec_space_handler(u32 function, acpi_physical_address address, 
static acpi_status

ec_parse_io_ports(struct acpi_resource *resource, void *context);



static struct acpi_ec *make_acpi_ec(void)

static void acpi_ec_free(struct acpi_ec *ec)

{

	if (first_ec == ec)

		first_ec = NULL;

	if (boot_ec == ec)

		boot_ec = NULL;

	kfree(ec);

}



static struct acpi_ec *acpi_ec_alloc(void)

{

	struct acpi_ec *ec = kzalloc(sizeof(struct acpi_ec), GFP_KERNEL);
@@ -1365,6 +1375,11 @@ ec_parse_device(acpi_handle handle, u32 Level, void *context, void **retval) 
	return AE_CTRL_TERMINATE;

}



/*

 * Note: This function returns an error code only when the address space

 *       handler is not installed, which means "not able to handle

 *       transactions".

 */

static int ec_install_handlers(struct acpi_ec *ec)

{

	acpi_status status;
@@ -1440,21 +1455,49 @@ static void ec_remove_handlers(struct acpi_ec *ec) 
	}

}



static struct acpi_ec *acpi_ec_alloc(void)

static int acpi_ec_setup(struct acpi_ec *ec)

{

	struct acpi_ec *ec;

	int ret;



	/* Check for boot EC */

	if (boot_ec) {

		ec = boot_ec;

		boot_ec = NULL;

		ec_remove_handlers(ec);

		if (first_ec == ec)

			first_ec = NULL;

	} else {

		ec = make_acpi_ec();

	ret = ec_install_handlers(ec);

	if (ret)

		return ret;



	/* First EC capable of handling transactions */

	if (!first_ec) {

		first_ec = ec;

		acpi_handle_info(first_ec->handle, "Used as first EC\n");

	}

	return ec;



	acpi_handle_info(ec->handle,

			 "GPE=0x%lx, EC_CMD/EC_SC=0x%lx, EC_DATA=0x%lx\n",

			 ec->gpe, ec->command_addr, ec->data_addr);

	return ret;

}



static int acpi_config_boot_ec(struct acpi_ec *ec, bool is_ecdt)

{

	int ret;



	if (boot_ec)

		ec_remove_handlers(boot_ec);



	/* Unset old boot EC */

	if (boot_ec != ec)

		acpi_ec_free(boot_ec);



	ret = acpi_ec_setup(ec);

	if (ret)

		return ret;



	/* Set new boot EC */

	if (!boot_ec) {

		boot_ec = ec;

		boot_ec_is_ecdt = is_ecdt;

		acpi_handle_info(boot_ec->handle, "Used as boot %s EC\n",

				 is_ecdt ? "ECDT" : "DSDT");

	}

	return ret;

}



static int acpi_ec_add(struct acpi_device *device)
@@ -1470,7 +1513,7 @@ static int acpi_ec_add(struct acpi_device *device) 
		return -ENOMEM;

	if (ec_parse_device(device->handle, 0, ec, NULL) !=

		AE_CTRL_TERMINATE) {

			kfree(ec);

			acpi_ec_free(ec);

			return -EINVAL;

	}
@@ -1478,8 +1521,6 @@ static int acpi_ec_add(struct acpi_device *device) 
	acpi_walk_namespace(ACPI_TYPE_METHOD, ec->handle, 1,

			    acpi_ec_register_query_methods, NULL, ec, NULL);



	if (!first_ec)

		first_ec = ec;

	device->driver_data = ec;



	ret = !!request_region(ec->data_addr, 1, "EC data");
@@ -1487,10 +1528,7 @@ static int acpi_ec_add(struct acpi_device *device) 
	ret = !!request_region(ec->command_addr, 1, "EC cmd");

	WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);



	pr_info("GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",

			  ec->gpe, ec->command_addr, ec->data_addr);



	ret = ec_install_handlers(ec);

	ret = acpi_config_boot_ec(ec, false);



	/* Reprobe devices depending on the EC */

	acpi_walk_dep_device_list(ec->handle);
@@ -1513,9 +1551,7 @@ static int acpi_ec_remove(struct acpi_device *device) 
	release_region(ec->data_addr, 1);

	release_region(ec->command_addr, 1);

	device->driver_data = NULL;

	if (ec == first_ec)

		first_ec = NULL;

	kfree(ec);

	acpi_ec_free(ec);

	return 0;

}
@@ -1567,13 +1603,10 @@ int __init acpi_ec_dsdt_probe(void) 
		ret = -ENODEV;

		goto error;

	}

	ret = ec_install_handlers(ec);



	ret = acpi_config_boot_ec(ec, false);

error:

	if (ret)

		kfree(ec);

	else

		first_ec = boot_ec = ec;

		acpi_ec_free(ec);

	return ret;

}
@@ -1671,7 +1704,6 @@ int __init acpi_ec_ecdt_probe(void) 
		goto error;

	}



	pr_info("EC description table is found, configuring boot EC\n");

	if (EC_FLAGS_CORRECT_ECDT) {

		ec->command_addr = ecdt_ptr->data.address;

		ec->data_addr = ecdt_ptr->control.address;
@@ -1681,12 +1713,10 @@ int __init acpi_ec_ecdt_probe(void) 
	}

	ec->gpe = ecdt_ptr->gpe;

	ec->handle = ACPI_ROOT_OBJECT;

	ret = ec_install_handlers(ec);

	ret = acpi_config_boot_ec(ec, true);

error:

	if (ret)

		kfree(ec);

	else

		first_ec = boot_ec = ec;

		acpi_ec_free(ec);

	return ret;

}

CRA Git | Maintained and supported by SUSTech CRA and CCSE