i2c: i2c-stm32f7: rework slave_id allocation
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Message ID 1571144589-3066-1-git-send-email-alain.volmat@st.com
State Accepted
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Series
  • i2c: i2c-stm32f7: rework slave_id allocation
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Commit Message

Alain Volmat Oct. 15, 2019, 1:03 p.m. UTC
The IP can handle two slave addresses. One address can either be
7 bits or 10 bits while the other can only be 7 bits.
In order to ensure that a 10 bits address can always be allocated
(assuming there is only one 7 bits address already allocated),
pick up the 7-bits only address slot in priority when performing a 7-bits
address allocation.

Fixes: 60d609f3 ("i2c: i2c-stm32f7: Add slave support")

Signed-off-by: Alain Volmat <alain.volmat@st.com>
---
 drivers/i2c/busses/i2c-stm32f7.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Pierre Yves MORDRET Oct. 22, 2019, 1:41 p.m. UTC | #1
Hello

Looks good

Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com>

Thx
Regards

On 10/15/19 3:03 PM, Alain Volmat wrote:
> The IP can handle two slave addresses. One address can either be
> 7 bits or 10 bits while the other can only be 7 bits.
> In order to ensure that a 10 bits address can always be allocated
> (assuming there is only one 7 bits address already allocated),
> pick up the 7-bits only address slot in priority when performing a 7-bits
> address allocation.
> 
> Fixes: 60d609f3 ("i2c: i2c-stm32f7: Add slave support")
> 
> Signed-off-by: Alain Volmat <alain.volmat@st.com>
> ---
>  drivers/i2c/busses/i2c-stm32f7.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
> index d36cf08461f7..cfae01b15243 100644
> --- a/drivers/i2c/busses/i2c-stm32f7.c
> +++ b/drivers/i2c/busses/i2c-stm32f7.c
> @@ -1265,7 +1265,7 @@ static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev,
>  	 * slave[0] supports 7-bit and 10-bit slave address
>  	 * slave[1] supports 7-bit slave address only
>  	 */
> -	for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
> +	for (i = STM32F7_I2C_MAX_SLAVE - 1; i >= 0; i--) {
>  		if (i == 1 && (slave->flags & I2C_CLIENT_PEC))
>  			continue;
>  		if (!i2c_dev->slave[i]) {
>
Wolfram Sang Oct. 24, 2019, 6:35 p.m. UTC | #2
On Tue, Oct 15, 2019 at 03:03:09PM +0200, Alain Volmat wrote:
> The IP can handle two slave addresses. One address can either be
> 7 bits or 10 bits while the other can only be 7 bits.
> In order to ensure that a 10 bits address can always be allocated
> (assuming there is only one 7 bits address already allocated),
> pick up the 7-bits only address slot in priority when performing a 7-bits
> address allocation.
> 
> Fixes: 60d609f3 ("i2c: i2c-stm32f7: Add slave support")
> 
> Signed-off-by: Alain Volmat <alain.volmat@st.com>

Applied to for-next, thanks!

Patch
diff mbox series

diff --git a/drivers/i2c/busses/i2c-stm32f7.c b/drivers/i2c/busses/i2c-stm32f7.c
index d36cf08461f7..cfae01b15243 100644
--- a/drivers/i2c/busses/i2c-stm32f7.c
+++ b/drivers/i2c/busses/i2c-stm32f7.c
@@ -1265,7 +1265,7 @@  static int stm32f7_i2c_get_free_slave_id(struct stm32f7_i2c_dev *i2c_dev,
 	 * slave[0] supports 7-bit and 10-bit slave address
 	 * slave[1] supports 7-bit slave address only
 	 */
-	for (i = 0; i < STM32F7_I2C_MAX_SLAVE; i++) {
+	for (i = STM32F7_I2C_MAX_SLAVE - 1; i >= 0; i--) {
 		if (i == 1 && (slave->flags & I2C_CLIENT_PEC))
 			continue;
 		if (!i2c_dev->slave[i]) {