On Mon, Nov 25, 2024 at 10:15:21PM +0800, carlos.song@xxxxxxx wrote:
> From: Carlos Song <carlos.song@xxxxxxx>
>
> Add "i2c_clk_rate / 2" check to avoid "divide by zero warning".
> i2c_clk_rate may be zero if i2c clock is disabled.
>
> Signed-off-by: Carlos Song <carlos.song@xxxxxxx>
> Signed-off-by: Clark Wang <xiaoning.wang@xxxxxxx>
> Signed-off-by: Haibo Chen <haibo.chen@xxxxxxx>
> ---
You sent this patch twice?
Reviewed-by: Frank Li <Frank.Li@xxxxxxx>
> drivers/i2c/busses/i2c-imx.c | 23 +++++++++++++++++------
> 1 file changed, 17 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
> index 2c782cdc26bd..5ed4cb61e262 100644
> --- a/drivers/i2c/busses/i2c-imx.c
> +++ b/drivers/i2c/busses/i2c-imx.c
> @@ -623,8 +623,8 @@ static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
> return 0;
> }
>
> -static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
> - unsigned int i2c_clk_rate)
> +static int i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
> + unsigned int i2c_clk_rate)
> {
> struct imx_i2c_clk_pair *i2c_clk_div = i2c_imx->hwdata->clk_div;
> unsigned int div;
> @@ -639,7 +639,11 @@ static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
>
> /* Divider value calculation */
> if (i2c_imx->cur_clk == i2c_clk_rate)
> - return;
> + return 0;
> +
> + /* Keep the denominator of the following program always NOT equal to 0. */
> + if (!(i2c_clk_rate / 2))
> + return -EINVAL;
>
> i2c_imx->cur_clk = i2c_clk_rate;
>
> @@ -670,6 +674,8 @@ static void i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
> dev_dbg(&i2c_imx->adapter.dev, "IFDR[IC]=0x%x, REAL DIV=%d\n",
> i2c_clk_div[i].val, i2c_clk_div[i].div);
> #endif
> +
> + return 0;
> }
>
> static int i2c_imx_clk_notifier_call(struct notifier_block *nb,
> @@ -679,11 +685,12 @@ static int i2c_imx_clk_notifier_call(struct notifier_block *nb,
> struct imx_i2c_struct *i2c_imx = container_of(nb,
> struct imx_i2c_struct,
> clk_change_nb);
> + int ret = 0;
>
> if (action & POST_RATE_CHANGE)
> - i2c_imx_set_clk(i2c_imx, ndata->new_rate);
> + ret = i2c_imx_set_clk(i2c_imx, ndata->new_rate);
>
> - return NOTIFY_OK;
> + return notifier_from_errno(ret);
> }
>
> static int i2c_imx_start(struct imx_i2c_struct *i2c_imx, bool atomic)
> @@ -1782,7 +1789,11 @@ static int i2c_imx_probe(struct platform_device *pdev)
> i2c_imx->bitrate = pdata->bitrate;
> i2c_imx->clk_change_nb.notifier_call = i2c_imx_clk_notifier_call;
> clk_notifier_register(i2c_imx->clk, &i2c_imx->clk_change_nb);
> - i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk));
> + ret = i2c_imx_set_clk(i2c_imx, clk_get_rate(i2c_imx->clk));
> + if (ret < 0) {
> + dev_err(&pdev->dev, "can't get I2C clock\n");
> + goto clk_notifier_unregister;
> + }
>
> i2c_imx_reset_regs(i2c_imx);
>
> --
> 2.34.1
>
