[U-Boot,1/2] mxs: i2c: Restore speed setting after block reset

Message ID 1354335427-8869-1-git-send-email-marex@denx.de
State Accepted
Delegated to: Heiko Schocher
Headers show

Commit Message

Marek Vasut Dec. 1, 2012, 4:17 a.m.
The I2C block reset configures the I2C bus speed to strange value.
Read the I2C speed from the block before reseting the block and
restore it afterwards, so the I2C operates correctly. This issue
can be replicated by doing unsuccessful I2C transfer, after such
transfer finishes, the I2C block clock speed is misconfigured.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
 drivers/i2c/mxs_i2c.c |    3 +++
 1 file changed, 3 insertions(+)


diff --git a/drivers/i2c/mxs_i2c.c b/drivers/i2c/mxs_i2c.c
index 006fb91..73a6659 100644
--- a/drivers/i2c/mxs_i2c.c
+++ b/drivers/i2c/mxs_i2c.c
@@ -40,6 +40,7 @@  void mxs_i2c_reset(void)
 	struct mxs_i2c_regs *i2c_regs = (struct mxs_i2c_regs *)MXS_I2C0_BASE;
 	int ret;
+	int speed = i2c_get_bus_speed();
 	ret = mxs_reset_block(&i2c_regs->hw_i2c_ctrl0_reg);
 	if (ret) {
@@ -53,6 +54,8 @@  void mxs_i2c_reset(void)
 	writel(I2C_QUEUECTRL_PIO_QUEUE_MODE, &i2c_regs->hw_i2c_queuectrl_set);
+	i2c_set_bus_speed(speed);
 void mxs_i2c_setup_read(uint8_t chip, int len)