[U-Boot] question about software i2c multi instance
Hi Heiko, After check the software i2c code, I found it can not support multi instances, although it has I2C_SOFT_DECLARATIONS2, I2C_SOFT_DECLARATIONS3, I2C_SOFT_DECLARATIONS4. Because, when do GPIO operation, there is only one pair of CONFIG_SOFT_I2C_GPIO_SCL and CONFIG_SOFT_I2C_GPIO_SDA. So, if want to support multi instances, it needs to extend the GPIO configuration for SCL/SDA, am I right?
Thanks.
Best Regards, Bo Shen
Hello Bo,
Am 20.03.2015 10:44, schrieb Bo Shen:
Hi Heiko, After check the software i2c code, I found it can not support multi instances, although it has I2C_SOFT_DECLARATIONS2, I2C_SOFT_DECLARATIONS3, I2C_SOFT_DECLARATIONS4. Because, when do GPIO operation, there is only one pair of CONFIG_SOFT_I2C_GPIO_SCL and CONFIG_SOFT_I2C_GPIO_SDA. So, if want to support multi instances, it needs to extend the GPIO configuration for SCL/SDA, am I right?
Prefered way should be to use DM, Przemyslaw posted patches for the soft-i2c driver, see http://lists.denx.de/pipermail/u-boot/2015-March/207641.html
maybe you can try this?
If not, you are right, you must define your own I2C_SCL/I2C_SDA/I2C_READ/I2C_INIT defines, for example:
# define I2C_SCL(bit) \ do { \ switch(I2C_ADAP_HWNR) { case 0: gpio_direction_output(CONFIG_SOFT_I2C_GPIO_SCL_0, bit); \ break; case 1: gpio_direction_output(CONFIG_SOFT_I2C_GPIO_SCL_1, bit); \ break; [...] I2C_GPIO_SYNC; \ } while (0)
bye, Heiko
Hi Heiko,
On 03/20/2015 06:10 PM, Heiko Schocher wrote:
Hello Bo,
Am 20.03.2015 10:44, schrieb Bo Shen:
Hi Heiko, After check the software i2c code, I found it can not support multi instances, although it has I2C_SOFT_DECLARATIONS2, I2C_SOFT_DECLARATIONS3, I2C_SOFT_DECLARATIONS4. Because, when do GPIO operation, there is only one pair of CONFIG_SOFT_I2C_GPIO_SCL and CONFIG_SOFT_I2C_GPIO_SDA. So, if want to support multi instances, it needs to extend the GPIO configuration for SCL/SDA, am I right?
Prefered way should be to use DM, Przemyslaw posted patches for the soft-i2c driver, see http://lists.denx.de/pipermail/u-boot/2015-March/207641.html
maybe you can try this?
Thanks for your information. As I try to use the old version of U-Boot, it doesn't support DM well.
If not, you are right, you must define your own I2C_SCL/I2C_SDA/I2C_READ/I2C_INIT defines, for example:
# define I2C_SCL(bit) \ do { \ switch(I2C_ADAP_HWNR) { case 0:
gpio_direction_output(CONFIG_SOFT_I2C_GPIO_SCL_0, bit); \ break; case 1:
gpio_direction_output(CONFIG_SOFT_I2C_GPIO_SCL_1, bit); \ break; [...] I2C_GPIO_SYNC; \ } while (0)
For this, the I2C_SCL and I2C_SDA working, however for I2C_READ, it maybe need to modify the definition from micro to function, as the I2C_READ can not use do {} while.
Thanks again.
bye, Heiko
Best Regards, Bo Shen
Hi Bo,
Hi Heiko, After check the software i2c code, I found it can not support multi instances, although it has I2C_SOFT_DECLARATIONS2, I2C_SOFT_DECLARATIONS3, I2C_SOFT_DECLARATIONS4. Because, when do GPIO operation, there is only one pair of CONFIG_SOFT_I2C_GPIO_SCL and CONFIG_SOFT_I2C_GPIO_SDA. So, if want to support multi instances, it needs to extend the GPIO configuration for SCL/SDA, am I right?
Some time ago we had a similar problem with SW I2C code. Please look into Samsung's trats board implementation.
However, such approach might be outdated, since Przemek is working on porting this functionality to device model:
https://patchwork.ozlabs.org/patch/448460/
Thanks.
Best Regards, Bo Shen
Hi Lukasz,
On 03/23/2015 04:28 PM, Lukasz Majewski wrote:
Hi Bo,
Hi Heiko, After check the software i2c code, I found it can not support multi instances, although it has I2C_SOFT_DECLARATIONS2, I2C_SOFT_DECLARATIONS3, I2C_SOFT_DECLARATIONS4. Because, when do GPIO operation, there is only one pair of CONFIG_SOFT_I2C_GPIO_SCL and CONFIG_SOFT_I2C_GPIO_SDA. So, if want to support multi instances, it needs to extend the GPIO configuration for SCL/SDA, am I right?
Some time ago we had a similar problem with SW I2C code. Please look into Samsung's trats board implementation.
However, such approach might be outdated, since Przemek is working on porting this functionality to device model:
Thanks for your information. Now, I just do it as following to make it work. For next step, I will try to switch to use DM.
--->8--- diff --git a/drivers/i2c/soft_i2c.c b/drivers/i2c/soft_i2c.c index db9b402..b9cfbb8 100644 --- a/drivers/i2c/soft_i2c.c +++ b/drivers/i2c/soft_i2c.c @@ -126,6 +126,13 @@ DECLARE_GLOBAL_DATA_PTR; #define PRINTD(fmt,args...) #endif
+#ifdef I2C_READ_ADAP +static int soft_i2c_read_sda(void) +{ + I2C_READ_ADAP; +} +#endif + /*----------------------------------------------------------------------- * Local functions */ @@ -256,7 +263,11 @@ static int write_byte(uchar data) I2C_SCL(1); I2C_DELAY; I2C_DELAY; +#ifdef I2C_READ_ADAP + nack = soft_i2c_read_sda(); +#else nack = I2C_READ; +#endif I2C_SCL(0); I2C_DELAY; I2C_ACTIVE; @@ -286,7 +297,11 @@ static uchar read_byte(int ack) I2C_SCL(1); I2C_DELAY; data <<= 1; +#ifdef I2C_READ_ADAP + data |= soft_i2c_read_sda(); +#else data |= I2C_READ; +#endif I2C_DELAY; } send_ack(ack); ---8<---
Thanks again.
Best Regards, Bo Shen
Hello Bo,
On 03/23/2015 09:36 AM, Bo Shen wrote:
Hi Lukasz,
On 03/23/2015 04:28 PM, Lukasz Majewski wrote:
Hi Bo,
Hi Heiko, After check the software i2c code, I found it can not support multi instances, although it has I2C_SOFT_DECLARATIONS2, I2C_SOFT_DECLARATIONS3, I2C_SOFT_DECLARATIONS4. Because, when do GPIO operation, there is only one pair of CONFIG_SOFT_I2C_GPIO_SCL and CONFIG_SOFT_I2C_GPIO_SDA. So, if want to support multi instances, it needs to extend the GPIO configuration for SCL/SDA, am I right?
Some time ago we had a similar problem with SW I2C code. Please look into Samsung's trats board implementation.
However, such approach might be outdated, since Przemek is working on porting this functionality to device model:
Thanks for your information. Now, I just do it as following to make it work. For next step, I will try to switch to use DM.
--->8--- diff --git a/drivers/i2c/soft_i2c.c b/drivers/i2c/soft_i2c.c index db9b402..b9cfbb8 100644 --- a/drivers/i2c/soft_i2c.c +++ b/drivers/i2c/soft_i2c.c @@ -126,6 +126,13 @@ DECLARE_GLOBAL_DATA_PTR; #define PRINTD(fmt,args...) #endif
+#ifdef I2C_READ_ADAP +static int soft_i2c_read_sda(void) +{
I2C_READ_ADAP;+} +#endif
- /*-----------------------------------------------------------------------
*/
- Local functions
@@ -256,7 +263,11 @@ static int write_byte(uchar data) I2C_SCL(1); I2C_DELAY; I2C_DELAY; +#ifdef I2C_READ_ADAP
nack = soft_i2c_read_sda();+#else nack = I2C_READ; +#endif I2C_SCL(0); I2C_DELAY; I2C_ACTIVE; @@ -286,7 +297,11 @@ static uchar read_byte(int ack) I2C_SCL(1); I2C_DELAY; data <<= 1; +#ifdef I2C_READ_ADAP
data |= soft_i2c_read_sda();+#else data |= I2C_READ; +#endif I2C_DELAY; } send_ack(ack); ---8<---
Thanks again.
Best Regards, Bo Shen
Please look into the Trats2 board code in:
board/samsung/trats2/trats2.c lines 130-145 include/configs/trats2.h lines 180-185
It doesn't require i2c driver modifications. But anyway I recommend to use the code of my patches, which Lukasz mentioned.
Best regards,
Hi Przemyslaw Marczak,
On 03/23/2015 04:47 PM, Przemyslaw Marczak wrote:
Please look into the Trats2 board code in:
board/samsung/trats2/trats2.c lines 130-145 include/configs/trats2.h lines 180-185
It doesn't require i2c driver modifications. But anyway I recommend to use the code of my patches, which Lukasz mentioned.
Thanks for your information. I will try this method. Thanks again.
Best regards,
Przemyslaw Marczak Samsung R&D Institute Poland Samsung Electronics p.marczak@samsung.com
Best Regards, Bo shen
participants (4)
-
Bo Shen -
Heiko Schocher -
Lukasz Majewski -
Przemyslaw Marczak