[linux-yocto] [PATCH 1/2] mfd: intel-lpss: Pass I2C configuration via properties on BXT

Weifeng Voon weifeng.voon at intel.com
Thu Jun 16 00:56:32 PDT 2016


From: Mika Westerberg <mika.westerberg at 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 at linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko at linux.intel.com>
Signed-off-by: Lee Jones <lee.jones at linaro.org>
(cherry picked from commit 0343b2f4e4a52c907d7676ce3159e0b5e7f0301c)
Signed-off-by: Weifeng Voon <weifeng.voon at 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[] = {
-- 
1.9.1



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