On Thu, 17 Aug 2023 at 17:46, Huangzheng Lai <Huangzheng.Lai@xxxxxxxxxx> wrote:
>
> When IIC-slaves supporting different frequencies use the same IIC
%s/I2C/IIC
> controller, the IIC controller usually only operates at lower frequencies.
> In order to improve the performance of IIC-slaves transmission supporting
> faster frequencies, we dynamically configure the IIC operating frequency
> based on the value of the input parameter msg ->flag.
>
> Signed-off-by: Huangzheng Lai <Huangzheng.Lai@xxxxxxxxxx>
> ---
> drivers/i2c/busses/i2c-sprd.c | 17 ++++++++++++++++-
> 1 file changed, 16 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-sprd.c b/drivers/i2c/busses/i2c-sprd.c
> index 549b60dd3273..02c11a9ff2da 100644
> --- a/drivers/i2c/busses/i2c-sprd.c
> +++ b/drivers/i2c/busses/i2c-sprd.c
> @@ -75,7 +75,14 @@
> #define SPRD_I2C_PM_TIMEOUT 1000
> /* timeout (ms) for transfer message */
> #define I2C_XFER_TIMEOUT 1000
> -
> +/* dynamic modify clk_freq flag */
> +#define I2C_3M4_FLAG 0x0100
#define <space> I2C_3M4_FLAG <tab> 0x0100
> +#define I2C_1M_FLAG 0x0080
> +#define I2C_400K_FLAG 0x0040
> +
> +#define I2C_FREQ_400K 400000
> +#define I2C_FREQ_1M 1000000
> +#define I2C_FREQ_3_4M 3400000
ditto
> /* SPRD i2c data structure */
> struct sprd_i2c {
> struct i2c_adapter adap;
> @@ -94,6 +101,8 @@ struct sprd_i2c {
> int err;
> };
>
> +static void sprd_i2c_set_clk(struct sprd_i2c *i2c_dev, u32 freq);
I would suggest moving this whole function above its caller.
> +
> static void sprd_i2c_set_count(struct sprd_i2c *i2c_dev, u32 count)
> {
> writel(count, i2c_dev->base + I2C_COUNT);
> @@ -269,6 +278,12 @@ static int sprd_i2c_handle_msg(struct i2c_adapter *i2c_adap,
> sprd_i2c_send_stop(i2c_dev, !!is_last_msg);
> }
>
> + if (msg->flags & I2C_400K_FLAG)
Where does this flag set? I'm not sure we can use msg->flags like
this. I don't know i2c very well.
Thanks,
Chunyan
> + sprd_i2c_set_clk(i2c_dev, I2C_FREQ_400K);
> + else if (msg->flags & I2C_1M_FLAG)
> + sprd_i2c_set_clk(i2c_dev, I2C_FREQ_1M);
> + else if (msg->flags & I2C_3M4_FLAG)
> + sprd_i2c_set_clk(i2c_dev, I2C_FREQ_3_4M);
> /*
> * We should enable rx fifo full interrupt to get data when receiving
> * full data.
> --
> 2.17.1
>
