Messages in this thread | | | Date | Mon, 23 Oct 2023 19:43:36 +0800 | Subject | Re: [PATCH V2 7/7] i2c: sprd: Add I2C_NACK_EN and I2C_TRANS_EN control bits | From | Baolin Wang <> |
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On 10/23/2023 4:11 PM, Huangzheng Lai wrote: > The new I2C IP version on the UNISOC platform has added I2C_NACK_EN and > I2C_TRANS_EN control bits. To ensure that the I2C controller can initiate > transmission smoothly, these two bits need to be configured.
What is the side impact for old hardwares that does not support these 2 bits?
> Signed-off-by: Huangzheng Lai <Huangzheng.Lai@unisoc.com> > --- > drivers/i2c/busses/i2c-sprd.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c > index dbdac89ad482..431c0db84d22 100644 > --- a/drivers/i2c/busses/i2c-sprd.c > +++ b/drivers/i2c/busses/i2c-sprd.c > @@ -33,6 +33,8 @@ > #define ADDR_RST 0x2c > > /* I2C_CTL */ > +#define I2C_NACK_EN BIT(22) > +#define I2C_TRANS_EN BIT(21) > #define STP_EN BIT(20) > #define FIFO_AF_LVL_MASK GENMASK(19, 16) > #define FIFO_AF_LVL 16 > @@ -366,7 +368,7 @@ static void sprd_i2c_enable(struct sprd_i2c *i2c_dev) > sprd_i2c_clear_irq(i2c_dev); > > tmp = readl(i2c_dev->base + I2C_CTL); > - writel(tmp | I2C_EN | I2C_INT_EN, i2c_dev->base + I2C_CTL); > + writel(tmp | I2C_EN | I2C_INT_EN | I2C_NACK_EN | I2C_TRANS_EN, i2c_dev->base + I2C_CTL); > } > > static int sprd_i2c_master_xfer(struct i2c_adapter *i2c_adap,
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