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Subject[PATCH v1 1/1] mfd: intel-lpss: Pass I2C configuration via properties on BXT
Date
From: Mika Westerberg <mika.westerberg@linux.intel.com>

I2C host controller need to be configured properly in order to meet I2C
timings specified in the I2C protocol specification. Some Intel Broxton
based machines do not have this information in the ACPI namespace (or the
boot firmware does not support ACPI at all) so we use build-in device
properties instead.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/mfd/intel-lpss-acpi.c | 12 ++++++++++++
drivers/mfd/intel-lpss-pci.c | 12 ++++++++++++
2 files changed, 24 insertions(+)

diff --git a/drivers/mfd/intel-lpss-acpi.c b/drivers/mfd/intel-lpss-acpi.c
index 06f00d6..5a8d9c7 100644
--- a/drivers/mfd/intel-lpss-acpi.c
+++ b/drivers/mfd/intel-lpss-acpi.c
@@ -44,8 +44,20 @@ static const struct intel_lpss_platform_info bxt_info = {
.clk_rate = 100000000,
};

+static struct property_entry bxt_i2c_properties[] = {
+ PROPERTY_ENTRY_U32("i2c-sda-hold-time-ns", 42),
+ PROPERTY_ENTRY_U32("i2c-sda-falling-time-ns", 171),
+ PROPERTY_ENTRY_U32("i2c-scl-falling-time-ns", 208),
+ { },
+};
+
+static struct property_set bxt_i2c_pset = {
+ .properties = bxt_i2c_properties,
+};
+
static const struct intel_lpss_platform_info bxt_i2c_info = {
.clk_rate = 133000000,
+ .pset = &bxt_i2c_pset,
};

static const struct acpi_device_id intel_lpss_acpi_ids[] = {
diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c
index a7136c7..92b456f 100644
--- a/drivers/mfd/intel-lpss-pci.c
+++ b/drivers/mfd/intel-lpss-pci.c
@@ -107,8 +107,20 @@ static const struct intel_lpss_platform_info bxt_uart_info = {
.pset = &uart_pset,
};

+static struct property_entry bxt_i2c_properties[] = {
+ PROPERTY_ENTRY_U32("i2c-sda-hold-time-ns", 42),
+ PROPERTY_ENTRY_U32("i2c-sda-falling-time-ns", 171),
+ PROPERTY_ENTRY_U32("i2c-scl-falling-time-ns", 208),
+ { },
+};
+
+static struct property_set bxt_i2c_pset = {
+ .properties = bxt_i2c_properties,
+};
+
static const struct intel_lpss_platform_info bxt_i2c_info = {
.clk_rate = 133000000,
+ .pset = &bxt_i2c_pset,
};

static const struct pci_device_id intel_lpss_pci_ids[] = {
--
2.7.0.rc3
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