Re: [PATCH v2] i2c: busses: Use min() to improve code

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Sat,  5 Jul 2025 19:44:35 +0800
Qianfeng Rong <rongqianfeng@vivo.com> wrote:

> Use min() to reduce the code and improve its readability.
> 
> The type of the max parameter in the st_i2c_rd_fill_tx_fifo()
> was changed from int to u32, because the max parameter passed
> in is always greater than 0.
> 
> Signed-off-by: Qianfeng Rong <rongqianfeng@vivo.com>
> Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Drive by review...

I'd add Wolfram as +CC at least.  May well pick it off the list
of course.


> ---
>  drivers/i2c/busses/i2c-st.c | 12 +++---------
>  1 file changed, 3 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/i2c/busses/i2c-st.c b/drivers/i2c/busses/i2c-st.c
> index 750fff3d2389..285d8a05ab36 100644
> --- a/drivers/i2c/busses/i2c-st.c
> +++ b/drivers/i2c/busses/i2c-st.c
> @@ -422,10 +422,7 @@ static void st_i2c_wr_fill_tx_fifo(struct st_i2c_dev *i2c_dev)
>  	tx_fstat = readl_relaxed(i2c_dev->base + SSC_TX_FSTAT);
>  	tx_fstat &= SSC_TX_FSTAT_STATUS;
>  
> -	if (c->count < (SSC_TXFIFO_SIZE - tx_fstat))
> -		i = c->count;
> -	else
> -		i = SSC_TXFIFO_SIZE - tx_fstat;
> +	i = min(c->count, SSC_TXFIFO_SIZE - tx_fstat);

Add 
#include <linux/minmax.h>


Given it is now one statement perhaps cleaner toput it
as the loop initializer 

	for (i = min(c->count, SSC_TXFIFO_SIZE - tx_fstat);
	     i > 0; i--, c->count--, c->buf++)

>  
>  	for (; i > 0; i--, c->count--, c->buf++)
>  		st_i2c_write_tx_fifo(i2c_dev, *c->buf);
> @@ -439,7 +436,7 @@ static void st_i2c_wr_fill_tx_fifo(struct st_i2c_dev *i2c_dev)
>   * This functions fills the Tx FIFO with fixed pattern when
>   * in read mode to trigger clock.
>   */
> -static void st_i2c_rd_fill_tx_fifo(struct st_i2c_dev *i2c_dev, int max)
> +static void st_i2c_rd_fill_tx_fifo(struct st_i2c_dev *i2c_dev, u32 max)
>  {
>  	struct st_i2c_client *c = &i2c_dev->client;
>  	u32 tx_fstat, sta;
> @@ -452,10 +449,7 @@ static void st_i2c_rd_fill_tx_fifo(struct st_i2c_dev *i2c_dev, int max)
>  	tx_fstat = readl_relaxed(i2c_dev->base + SSC_TX_FSTAT);
>  	tx_fstat &= SSC_TX_FSTAT_STATUS;
>  
> -	if (max < (SSC_TXFIFO_SIZE - tx_fstat))
> -		i = max;
> -	else
> -		i = SSC_TXFIFO_SIZE - tx_fstat;
> +	i = min(max, SSC_TXFIFO_SIZE - tx_fstat);
>  
>  	for (; i > 0; i--, c->xfered++)
Same here.

>  		st_i2c_write_tx_fifo(i2c_dev, 0xff);