lkml.org 
[lkml]   [2014]   [Aug]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 2/2] i2c: designware: add speed mode device tree setting
Date
From: Alan Tull <atull@opensource.altera.com>

Add "speed-mode" Device Tree property to select between
standard and fast i2c mode. Previously, driver was hardwired
as fast mode. Default to fast mode if property is not
present.

Signed-off-by: Alan Tull <atull@opensource.altera.com>
---
drivers/i2c/busses/i2c-designware-platdrv.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index bc87733..3fdc775 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -122,7 +122,7 @@ static int dw_i2c_probe(struct platform_device *pdev)
struct dw_i2c_dev *dev;
struct i2c_adapter *adap;
struct resource *mem;
- int irq, r;
+ int irq, r, speed_prop, ret, speed = DW_IC_CON_SPEED_FAST;

irq = platform_get_irq(pdev, 0);
if (irq < 0) {
@@ -167,6 +167,11 @@ static int dw_i2c_probe(struct platform_device *pdev)
of_property_read_u32(pdev->dev.of_node,
"i2c-scl-falling-time-ns",
&dev->scl_falling_time);
+
+ ret = of_property_read_u32(pdev->dev.of_node,
+ "speed-mode", &speed_prop);
+ if (!ret && (speed_prop == 0))
+ speed = DW_IC_CON_SPEED_STD;
}

dev->functionality =
@@ -177,7 +182,7 @@ static int dw_i2c_probe(struct platform_device *pdev)
I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_I2C_BLOCK;
dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |
- DW_IC_CON_RESTART_EN | DW_IC_CON_SPEED_FAST;
+ DW_IC_CON_RESTART_EN | speed;

/* Try first if we can configure the device from ACPI */
r = dw_i2c_acpi_configure(pdev);
--
1.7.9.5


\
 
 \ /
  Last update: 2014-08-19 21:21    [W:0.058 / U:0.116 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site