diff options
Diffstat (limited to 'drivers/i2c')
-rw-r--r-- | drivers/i2c/busses/i2c-designware-platdrv.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c index 73d58415bbc1..472b88285c75 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -24,6 +24,7 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/delay.h> +#include <linux/dmi.h> #include <linux/i2c.h> #include <linux/clk.h> #include <linux/clk-provider.h> @@ -51,6 +52,22 @@ static u32 i2c_dw_get_clk_rate_khz(struct dw_i2c_dev *dev) } #ifdef CONFIG_ACPI +/* + * The HCNT/LCNT information coming from ACPI should be the most accurate + * for given platform. However, some systems get it wrong. On such systems + * we get better results by calculating those based on the input clock. + */ +static const struct dmi_system_id dw_i2c_no_acpi_params[] = { + { + .ident = "Dell Inspiron 7348", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), + DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron 7348"), + }, + }, + { } +}; + static void dw_i2c_acpi_params(struct platform_device *pdev, char method[], u16 *hcnt, u16 *lcnt, u32 *sda_hold) { @@ -58,6 +75,9 @@ static void dw_i2c_acpi_params(struct platform_device *pdev, char method[], acpi_handle handle = ACPI_HANDLE(&pdev->dev); union acpi_object *obj; + if (dmi_check_system(dw_i2c_no_acpi_params)) + return; + if (ACPI_FAILURE(acpi_evaluate_object(handle, method, NULL, &buf))) return; |