diff mbox

[v2] i2c: rk3x: fix bug that cause transfer fails in maste receive mode

Message ID 1408657107-8715-1-git-send-email-addy.ke@rock-chips.com
State Superseded
Headers show

Commit Message

addy ke Aug. 21, 2014, 9:38 p.m. UTC
In rk3x SOC, the I2C controller can receive/transmit up to 32 bytes data
in one chunk, so the size of data to be write/read to/from TXDATAx/RXDATAx
must be less than or equal 32 bytes at a time.

Tested on rk3288-pinky board, elan receive 158 bytes data.

Acked-by: Max Schwarz <max.schwarz@online.de>
Signed-off-by: Addy Ke <addy.ke@rock-chips.com>
---
Changes in v2:
- Use cleaner syntax as suggested by Sergei.
- Update commit message as suggested by Wolfram.

 drivers/i2c/busses/i2c-rk3x.c | 4 ++++
 1 file changed, 4 insertions(+)

Comments

Doug Anderson Aug. 22, 2014, 1:14 a.m. UTC | #1
Addy,

Title should probably have "master", not "maste"

On Thu, Aug 21, 2014 at 2:38 PM, Addy Ke <addy.ke@rock-chips.com> wrote:
> In rk3x SOC, the I2C controller can receive/transmit up to 32 bytes data
> in one chunk, so the size of data to be write/read to/from TXDATAx/RXDATAx
> must be less than or equal 32 bytes at a time.
>
> Tested on rk3288-pinky board, elan receive 158 bytes data.
>
> Acked-by: Max Schwarz <max.schwarz@online.de>
> Signed-off-by: Addy Ke <addy.ke@rock-chips.com>
> ---
> Changes in v2:
> - Use cleaner syntax as suggested by Sergei.
> - Update commit message as suggested by Wolfram.
>
>  drivers/i2c/busses/i2c-rk3x.c | 4 ++++
>  1 file changed, 4 insertions(+)
>
> diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
> index 69e1185..806724a 100644
> --- a/drivers/i2c/busses/i2c-rk3x.c
> +++ b/drivers/i2c/busses/i2c-rk3x.c
> @@ -323,6 +323,10 @@ static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd)
>         /* ack interrupt */
>         i2c_writel(i2c, REG_INT_MBRF, REG_IPD);
>
> +       /* Can only handle a maximum of 32 bytes at a time */
> +       if (unlikely(len > 32))
> +               len  = 32;

nit: one space before "=", not two.

Tested-by: Doug Anderson <dianders@chromium.org>
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diff mbox

Patch

diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
index 69e1185..806724a 100644
--- a/drivers/i2c/busses/i2c-rk3x.c
+++ b/drivers/i2c/busses/i2c-rk3x.c
@@ -323,6 +323,10 @@  static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd)
 	/* ack interrupt */
 	i2c_writel(i2c, REG_INT_MBRF, REG_IPD);
 
+	/* Can only handle a maximum of 32 bytes at a time */
+	if (unlikely(len > 32))
+		len  = 32;
+
 	/* read the data from receive buffer */
 	for (i = 0; i < len; ++i) {
 		if (i % 4 == 0)