From e0d9727c111a5917a1184c71c1a8e6f78c7fc41d Mon Sep 17 00:00:00 2001 From: Luca Coelho Date: Thu, 13 Oct 2016 10:07:07 +0300 Subject: [PATCH] iwlwifi: pcie: fix SPLC structure parsing The SPLC data parsing is too restrictive and was not trying find the correct element for WiFi. This causes problems with some BIOSes where the SPLC method exists, but doesn't have a WiFi entry on the first element of the list. The domain type values are also incorrect according to the specification. Fix this by complying with the actual specification. Additionally, replace all occurrences of SPLX to SPLC, since SPLX is only a structure internal to the ACPI tables, and may not even exist. Fixes: bcb079a14d75 ("iwlwifi: pcie: retrieve and parse ACPI power limitations") Reported-by: Chris Rorvick Tested-by: Paul Bolle Tested-by: Chris Rorvick Signed-off-by: Luca Coelho --- drivers/net/wireless/intel/iwlwifi/pcie/drv.c | 79 +++++++++++-------- 1 file changed, 48 insertions(+), 31 deletions(-) diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/drv.c b/drivers/net/wireless/intel/iwlwifi/pcie/drv.c index 001be406a3d3..2f8134b2a504 100644 --- a/drivers/net/wireless/intel/iwlwifi/pcie/drv.c +++ b/drivers/net/wireless/intel/iwlwifi/pcie/drv.c @@ -541,48 +541,64 @@ static const struct pci_device_id iwl_hw_card_ids[] = { MODULE_DEVICE_TABLE(pci, iwl_hw_card_ids); #ifdef CONFIG_ACPI -#define SPL_METHOD "SPLC" -#define SPL_DOMAINTYPE_MODULE BIT(0) -#define SPL_DOMAINTYPE_WIFI BIT(1) -#define SPL_DOMAINTYPE_WIGIG BIT(2) -#define SPL_DOMAINTYPE_RFEM BIT(3) +#define ACPI_SPLC_METHOD "SPLC" +#define ACPI_SPLC_DOMAIN_WIFI (0x07) -static u64 splx_get_pwr_limit(struct iwl_trans *trans, union acpi_object *splx) +static u64 splc_get_pwr_limit(struct iwl_trans *trans, union acpi_object *splc) { - union acpi_object *limits, *domain_type, *power_limit; - - if (splx->type != ACPI_TYPE_PACKAGE || - splx->package.count != 2 || - splx->package.elements[0].type != ACPI_TYPE_INTEGER || - splx->package.elements[0].integer.value != 0) { - IWL_ERR(trans, "Unsupported splx structure\n"); + union acpi_object *data_pkg, *dflt_pwr_limit; + int i; + + /* We need at least two elements, one for the revision and one + * for the data itself. Also check that the revision is + * supported (currently only revision 0). + */ + if (splc->type != ACPI_TYPE_PACKAGE || + splc->package.count < 2 || + splc->package.elements[0].type != ACPI_TYPE_INTEGER || + splc->package.elements[0].integer.value != 0) { + IWL_DEBUG_INFO(trans, + "Unsupported structure returned by the SPLC method. Ignoring.\n"); return 0; } - limits = &splx->package.elements[1]; - if (limits->type != ACPI_TYPE_PACKAGE || - limits->package.count < 2 || - limits->package.elements[0].type != ACPI_TYPE_INTEGER || - limits->package.elements[1].type != ACPI_TYPE_INTEGER) { - IWL_ERR(trans, "Invalid limits element\n"); - return 0; + /* loop through all the packages to find the one for WiFi */ + for (i = 1; i < splc->package.count; i++) { + union acpi_object *domain; + + data_pkg = &splc->package.elements[i]; + + /* Skip anything that is not a package with the right + * amount of elements (i.e. at least 2 integers). + */ + if (data_pkg->type != ACPI_TYPE_PACKAGE || + data_pkg->package.count < 2 || + data_pkg->package.elements[0].type != ACPI_TYPE_INTEGER || + data_pkg->package.elements[1].type != ACPI_TYPE_INTEGER) + continue; + + domain = &data_pkg->package.elements[0]; + if (domain->integer.value == ACPI_SPLC_DOMAIN_WIFI) + break; + + data_pkg = NULL; } - domain_type = &limits->package.elements[0]; - power_limit = &limits->package.elements[1]; - if (!(domain_type->integer.value & SPL_DOMAINTYPE_WIFI)) { - IWL_DEBUG_INFO(trans, "WiFi power is not limited\n"); + if (!data_pkg) { + IWL_DEBUG_INFO(trans, + "No element for the WiFi domain returned by the SPLC method.\n"); return 0; } - return power_limit->integer.value; + dflt_pwr_limit = &data_pkg->package.elements[1]; + return dflt_pwr_limit->integer.value; } static void set_dflt_pwr_limit(struct iwl_trans *trans, struct pci_dev *pdev) { acpi_handle pxsx_handle; acpi_handle handle; - struct acpi_buffer splx = {ACPI_ALLOCATE_BUFFER, NULL}; + struct acpi_buffer splc = {ACPI_ALLOCATE_BUFFER, NULL}; acpi_status status; pxsx_handle = ACPI_HANDLE(&pdev->dev); @@ -593,23 +609,24 @@ static void set_dflt_pwr_limit(struct iwl_trans *trans, struct pci_dev *pdev) } /* Get the method's handle */ - status = acpi_get_handle(pxsx_handle, (acpi_string)SPL_METHOD, &handle); + status = acpi_get_handle(pxsx_handle, (acpi_string)ACPI_SPLC_METHOD, + &handle); if (ACPI_FAILURE(status)) { - IWL_DEBUG_INFO(trans, "SPL method not found\n"); + IWL_DEBUG_INFO(trans, "SPLC method not found\n"); return; } /* Call SPLC with no arguments */ - status = acpi_evaluate_object(handle, NULL, NULL, &splx); + status = acpi_evaluate_object(handle, NULL, NULL, &splc); if (ACPI_FAILURE(status)) { IWL_ERR(trans, "SPLC invocation failed (0x%x)\n", status); return; } - trans->dflt_pwr_limit = splx_get_pwr_limit(trans, splx.pointer); + trans->dflt_pwr_limit = splc_get_pwr_limit(trans, splc.pointer); IWL_DEBUG_INFO(trans, "Default power limit set to %lld\n", trans->dflt_pwr_limit); - kfree(splx.pointer); + kfree(splc.pointer); } #else /* CONFIG_ACPI */ -- 2.20.1