-----Original Message----- From: Joel Stanley joel@jms.id.au Sent: Thursday, May 19, 2022 8:28 AM To: Eddie James eajames@linux.ibm.com; Ryan Chen ryan_chen@aspeedtech.com; BMC-SW BMC-SW@aspeedtech.com Cc: U-Boot Mailing List u-boot@lists.denx.de; hs@denx.de Subject: Re: [PATCH] i2c: ast_i2c: Remove SCL direct drive mode
On Wed, 11 May 2022 at 20:52, Eddie James eajames@linux.ibm.com wrote:
SCL direct drive mode prevents communication with devices that do clock stretching, so disable. The Linux driver doesn't use this mode, and the engine can handle clock stretching.
Signed-off-by: Eddie James eajames@linux.ibm.com
Reviewed-by: Joel Stanley joel@jms.id.au
Reviewed-by: ryan_chen ryan_chen@aspeedtech.com
I have added the aspeed team to cc for their review.
Ryan, we discovered this fix when testing the tpm i2c driver on the ast2600.
Yes, it should remove. Thank for inform.
drivers/i2c/ast_i2c.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/i2c/ast_i2c.c b/drivers/i2c/ast_i2c.c index 2d3fecaa14..8b24a260c0 100644 --- a/drivers/i2c/ast_i2c.c +++ b/drivers/i2c/ast_i2c.c @@ -76,7 +76,7 @@ static void ast_i2c_init_bus(struct udevice *dev) /* Enable Master Mode. Assuming single-master */ writel(I2CD_MASTER_EN | I2CD_M_SDA_LOCK_EN
| I2CD_MULTI_MASTER_DIS | I2CD_M_SCL_DRIVE_EN,
| I2CD_MULTI_MASTER_DIS, &priv->regs->fcr); /* Enable Interrupts */ writel(I2CD_INTR_TX_ACK-- 2.27.0