From 62a615e083604d291af0cb18f9b4549531ea4f94 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Fri, 23 Oct 2015 12:16:41 +0300 Subject: [PATCH] mfd: core: redo ACPI matching of the children devices There is at least one board on the market, i.e. Intel Galileo Gen2, that uses _ADR to distinguish the devices under one actual device. Due to this we have to improve the quirk in the MFD core to handle that board. Acked-by: Rafael J. Wysocki Acked-by: Lee Jones Signed-off-by: Andy Shevchenko Signed-off-by: Wolfram Sang --- Documentation/acpi/enumeration.txt | 11 +++++-- drivers/mfd/mfd-core.c | 50 +++++++++++++++++++++--------- include/linux/mfd/core.h | 10 ++++-- 3 files changed, 51 insertions(+), 20 deletions(-) diff --git a/Documentation/acpi/enumeration.txt b/Documentation/acpi/enumeration.txt index b731b292e812..a91ec5af52df 100644 --- a/Documentation/acpi/enumeration.txt +++ b/Documentation/acpi/enumeration.txt @@ -347,13 +347,18 @@ For the first case, the MFD drivers do not need to do anything. The resulting child platform device will have its ACPI_COMPANION() set to point to the parent device. -If the ACPI namespace has a device that we can match using an ACPI id, -the id should be set like: +If the ACPI namespace has a device that we can match using an ACPI id or ACPI +adr, the cell should be set like: + + static struct mfd_cell_acpi_match my_subdevice_cell_acpi_match = { + .pnpid = "XYZ0001", + .adr = 0, + }; static struct mfd_cell my_subdevice_cell = { .name = "my_subdevice", /* set the resources relative to the parent */ - .acpi_pnpid = "XYZ0001", + .acpi_match = &my_subdevice_cell_acpi_match, }; The ACPI id "XYZ0001" is then used to lookup an ACPI device directly under diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c index c17635d3e504..60b60dc63ddd 100644 --- a/drivers/mfd/mfd-core.c +++ b/drivers/mfd/mfd-core.c @@ -82,29 +82,49 @@ static int mfd_platform_add_cell(struct platform_device *pdev, static void mfd_acpi_add_device(const struct mfd_cell *cell, struct platform_device *pdev) { - struct acpi_device *parent_adev; + const struct mfd_cell_acpi_match *match = cell->acpi_match; + struct acpi_device *parent, *child; struct acpi_device *adev; - parent_adev = ACPI_COMPANION(pdev->dev.parent); - if (!parent_adev) + parent = ACPI_COMPANION(pdev->dev.parent); + if (!parent) return; /* - * MFD child device gets its ACPI handle either from the ACPI - * device directly under the parent that matches the acpi_pnpid or - * it will use the parent handle if is no acpi_pnpid is given. + * MFD child device gets its ACPI handle either from the ACPI device + * directly under the parent that matches the either _HID or _CID, or + * _ADR or it will use the parent handle if is no ID is given. + * + * Note that use of _ADR is a grey area in the ACPI specification, + * though Intel Galileo Gen2 is using it to distinguish the children + * devices. */ - adev = parent_adev; - if (cell->acpi_pnpid) { - struct acpi_device_id ids[2] = {}; - struct acpi_device *child_adev; + adev = parent; + if (match) { + if (match->pnpid) { + struct acpi_device_id ids[2] = {}; - strlcpy(ids[0].id, cell->acpi_pnpid, sizeof(ids[0].id)); - list_for_each_entry(child_adev, &parent_adev->children, node) - if (acpi_match_device_ids(child_adev, ids)) { - adev = child_adev; - break; + strlcpy(ids[0].id, match->pnpid, sizeof(ids[0].id)); + list_for_each_entry(child, &parent->children, node) { + if (acpi_match_device_ids(child, ids)) { + adev = child; + break; + } } + } else { + unsigned long long adr; + acpi_status status; + + list_for_each_entry(child, &parent->children, node) { + status = acpi_evaluate_integer(child->handle, + "_ADR", NULL, + &adr); + if (ACPI_SUCCESS(status) && match->adr == adr) { + adev = child; + break; + } + } + } } ACPI_COMPANION_SET(&pdev->dev, adev); diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h index a76bc100bf97..27dac3ff18b9 100644 --- a/include/linux/mfd/core.h +++ b/include/linux/mfd/core.h @@ -18,6 +18,12 @@ struct irq_domain; +/* Matches ACPI PNP id, either _HID or _CID, or ACPI _ADR */ +struct mfd_cell_acpi_match { + const char *pnpid; + const unsigned long long adr; +}; + /* * This struct describes the MFD part ("cell"). * After registration the copy of this structure will become the platform data @@ -44,8 +50,8 @@ struct mfd_cell { */ const char *of_compatible; - /* Matches ACPI PNP id, either _HID or _CID */ - const char *acpi_pnpid; + /* Matches ACPI */ + const struct mfd_cell_acpi_match *acpi_match; /* * These resources can be specified relative to the parent device.