> -----Original Message-----
> From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
> Sent: Wednesday, October 25, 2023 9:17 PM
> To: linux-samsung-soc@xxxxxxxxxxxxxxx; linux-i2c@xxxxxxxxxxxxxxx
> Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>; Krzysztof Kozlowski
> <krzysztof.kozlowski@xxxxxxxxxx>; Alim Akhtar <alim.akhtar@xxxxxxxxxxx>;
> Andi Shyti <andi.shyti@xxxxxxxxxx>; Wolfram Sang <wsa@xxxxxxxxxx>
> Subject: [PATCH v2 3/3] i2c: s3c24xx: add support for atomic transfers
>
>
> Add support for atomic transfers using polling mode with interrupts
> intentionally disabled to get rid of the warning introduced by commit
> 63b96983a5dd ("i2c: core: introduce callbacks for atomic transfers")
> during system reboot and power-off.
>
> Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Reviewed-by: Chanho Park <chanho61.park@xxxxxxxxxxx>
> ---
> drivers/i2c/busses/i2c-s3c2410.c | 21 +++++++++++++++++++--
> 1 file changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-
> s3c2410.c
> index 8da85cb42980..586b82b30bdf 100644
> --- a/drivers/i2c/busses/i2c-s3c2410.c
> +++ b/drivers/i2c/busses/i2c-s3c2410.c
> @@ -76,6 +76,7 @@
> #define QUIRK_HDMIPHY (1 << 1)
> #define QUIRK_NO_GPIO (1 << 2)
> #define QUIRK_POLL (1 << 3)
> +#define QUIRK_ATOMIC (1 << 4)
>
> /* Max time to wait for bus to become idle after a xfer (in us) */
> #define S3C2410_IDLE_TIMEOUT 5000
> @@ -174,7 +175,7 @@ static inline void s3c24xx_i2c_master_complete(struct
> s3c24xx_i2c *i2c, int ret)
> if (ret)
> i2c->msg_idx = ret;
>
> - if (!(i2c->quirks & QUIRK_POLL))
> + if (!(i2c->quirks & (QUIRK_POLL | QUIRK_ATOMIC)))
> wake_up(&i2c->wait);
> }
>
> @@ -700,7 +701,7 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c,
> s3c24xx_i2c_enable_irq(i2c);
> s3c24xx_i2c_message_start(i2c, msgs);
>
> - if (i2c->quirks & QUIRK_POLL) {
> + if (i2c->quirks & (QUIRK_POLL | QUIRK_ATOMIC)) {
> while ((i2c->msg_num != 0) && is_ack(i2c)) {
> unsigned long stat = readl(i2c->regs +
> S3C2410_IICSTAT);
>
> @@ -774,6 +775,21 @@ static int s3c24xx_i2c_xfer(struct i2c_adapter *adap,
> return -EREMOTEIO;
> }
>
> +static int s3c24xx_i2c_xfer_atomic(struct i2c_adapter *adap,
> + struct i2c_msg *msgs, int num)
> +{
> + struct s3c24xx_i2c *i2c = (struct s3c24xx_i2c *)adap->algo_data;
> + int ret;
> +
> + disable_irq(i2c->irq);
> + i2c->quirks |= QUIRK_ATOMIC;
> + ret = s3c24xx_i2c_xfer(adap, msgs, num);
> + i2c->quirks &= ~QUIRK_ATOMIC;
> + enable_irq(i2c->irq);
> +
> + return ret;
> +}
> +
> /* declare our i2c functionality */
> static u32 s3c24xx_i2c_func(struct i2c_adapter *adap)
> {
> @@ -784,6 +800,7 @@ static u32 s3c24xx_i2c_func(struct i2c_adapter *adap)
> /* i2c bus registration info */
> static const struct i2c_algorithm s3c24xx_i2c_algorithm = {
> .master_xfer = s3c24xx_i2c_xfer,
> + .master_xfer_atomic = s3c24xx_i2c_xfer_atomic,
> .functionality = s3c24xx_i2c_func,
> };
>
> --
> 2.34.1
