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authorArd Biesheuvel <ard.biesheuvel@linaro.org>2019-05-24 18:26:46 +0200
committerHerbert Xu <herbert@gondor.apana.org.au>2019-05-30 15:35:45 +0800
commit4befedc045367c359de8ba021120fcf3bf797992 (patch)
tree9ee52abdbc85bdc84f8c140526ae27437af17e1e /drivers/i2c
parent8a82451bd04f57bfde8915f289fc2d1f9457abae (diff)
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i2c: acpi: permit bus speed to be discovered after enumeration
Currently, the I2C ACPI enumeration code only permits the max bus rate to be discovered before enumerating the slaves on the bus. In some cases, drivers for slave devices may require this information, e.g., some ATmel crypto drivers need to generate a so-called wake token of a fixed duration, regardless of the bus rate. So tweak the code so i2c_acpi_lookup_speed() is able to obtain this information after enumeration as well. Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/i2c-core-acpi.c6
1 files changed, 4 insertions, 2 deletions
diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
index 272800692088..7240cc07abb4 100644
--- a/drivers/i2c/i2c-core-acpi.c
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -115,8 +115,7 @@ static int i2c_acpi_do_lookup(struct acpi_device *adev,
struct list_head resource_list;
int ret;
- if (acpi_bus_get_status(adev) || !adev->status.present ||
- acpi_device_enumerated(adev))
+ if (acpi_bus_get_status(adev) || !adev->status.present)
return -EINVAL;
if (acpi_match_device_ids(adev, i2c_acpi_ignored_device_ids) == 0)
@@ -151,6 +150,9 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
lookup.info = info;
lookup.index = -1;
+ if (acpi_device_enumerated(adev))
+ return -EINVAL;
+
ret = i2c_acpi_do_lookup(adev, &lookup);
if (ret)
return ret;