[PATCH 1/2] I2C: Set I2C timing registers for mxs-i2c
Marek Vasut
marex at denx.de
Sun Apr 29 18:36:08 EDT 2012
This sets the bus to run at 400kHz, prior to this,
the bus frequency was undefined.
Cc: Linux I2C <linux-i2c at vger.kernel.org>
Cc: Detlev Zundel <dzu at denx.de>
Cc: Fabio Estevam <festevam at gmail.com>
Cc: Stefano Babic <sbabic at denx.de>
Cc: Wolfgang Denk <wd at denx.de>
Cc: Wolfram Sang <w.sang at pengutronix.de>
---
drivers/i2c/busses/i2c-mxs.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c
index 3d471d5..0d8e485 100644
--- a/drivers/i2c/busses/i2c-mxs.c
+++ b/drivers/i2c/busses/i2c-mxs.c
@@ -43,6 +43,10 @@
#define MXS_I2C_CTRL0_DIRECTION 0x00010000
#define MXS_I2C_CTRL0_XFER_COUNT(v) ((v) & 0x0000FFFF)
+#define MXS_I2C_TIMING0 (0x10)
+#define MXS_I2C_TIMING1 (0x20)
+#define MXS_I2C_TIMING2 (0x30)
+
#define MXS_I2C_CTRL1 (0x40)
#define MXS_I2C_CTRL1_SET (0x44)
#define MXS_I2C_CTRL1_CLR (0x48)
@@ -118,6 +122,12 @@ struct mxs_i2c_dev {
static void mxs_i2c_reset(struct mxs_i2c_dev *i2c)
{
mxs_reset_block(i2c->regs);
+
+ /* I2C is running at 400kHz */
+ writel(0x000f0007, i2c->regs + MXS_I2C_TIMING0);
+ writel(0x001f000f, i2c->regs + MXS_I2C_TIMING1);
+ writel(0x0015000d, i2c->regs + MXS_I2C_TIMING2);
+
writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET);
writel(MXS_I2C_QUEUECTRL_PIO_QUEUE_MODE,
i2c->regs + MXS_I2C_QUEUECTRL_SET);
--
1.7.10
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