commit 1d8c51ed2ddcc4161e6496cf14fcd83921c50ec8 upstream.
Some devices (eg. Dell XPS 9530, 2023) due to a firmware bug have a misconfigured clock divider, which should've been 1:1. This introduces quirk which conditionally re-configures the clock divider to 1:1.
Signed-off-by: Aleksandrs Vinarskis alex.vinarskis@gmail.com Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Link: https://lore.kernel.org/r/20231221185142.9224-3-alex.vinarskis@gmail.com Signed-off-by: Lee Jones lee@kernel.org --- drivers/mfd/intel-lpss-pci.c | 5 +++++ drivers/mfd/intel-lpss.c | 7 +++++++ drivers/mfd/intel-lpss.h | 5 +++++ 3 files changed, 17 insertions(+)
diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c index 07713a2f694f..8c00e0c695c5 100644 --- a/drivers/mfd/intel-lpss-pci.c +++ b/drivers/mfd/intel-lpss-pci.c @@ -34,6 +34,11 @@ static const struct pci_device_id quirk_ids[] = { PCI_DEVICE_SUB(PCI_VENDOR_ID_INTEL, 0x9d64, 0x152d, 0x1237), .driver_data = QUIRK_IGNORE_RESOURCE_CONFLICTS, }, + { + /* Dell XPS 9530 (2023) */ + PCI_DEVICE_SUB(PCI_VENDOR_ID_INTEL, 0x51fb, 0x1028, 0x0beb), + .driver_data = QUIRK_CLOCK_DIVIDER_UNITY, + }, { } };
diff --git a/drivers/mfd/intel-lpss.c b/drivers/mfd/intel-lpss.c index aafa0da5f8db..2a9018112dfc 100644 --- a/drivers/mfd/intel-lpss.c +++ b/drivers/mfd/intel-lpss.c @@ -300,6 +300,7 @@ static int intel_lpss_register_clock_divider(struct intel_lpss *lpss, { char name[32]; struct clk *tmp = *clk; + int ret;
snprintf(name, sizeof(name), "%s-enable", devname); tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0, @@ -316,6 +317,12 @@ static int intel_lpss_register_clock_divider(struct intel_lpss *lpss, return PTR_ERR(tmp); *clk = tmp;
+ if (lpss->info->quirks & QUIRK_CLOCK_DIVIDER_UNITY) { + ret = clk_set_rate(tmp, lpss->info->clk_rate); + if (ret) + return ret; + } + snprintf(name, sizeof(name), "%s-update", devname); tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL); diff --git a/drivers/mfd/intel-lpss.h b/drivers/mfd/intel-lpss.h index 2fa9ef916258..6f8f668f4c6f 100644 --- a/drivers/mfd/intel-lpss.h +++ b/drivers/mfd/intel-lpss.h @@ -19,6 +19,11 @@ * Set to ignore resource conflicts with ACPI declared SystemMemory regions. */ #define QUIRK_IGNORE_RESOURCE_CONFLICTS BIT(0) +/* + * Some devices have misconfigured clock divider due to a firmware bug. + * Set this to force the clock divider to 1:1 ratio. + */ +#define QUIRK_CLOCK_DIVIDER_UNITY BIT(1)
struct device; struct resource;