[RFC PATCH 1/2] i2c: add bus_freq_hz in i2c_adapter

[RFC PATCH 1/2] i2c: add bus_freq_hz in i2c_adapter

[Tudor Ambarus]

The clock-frequency property is not mandatory for the i2c buses. If it's
not present in device tree, the buses usually asume that it is 100kHZ.
There are i2c clients that need to know the i2c bus frequency in order to
compute their wake token. Spare the clients of making (wrong) assumptions
and save the bus frequency in the i2c_adapter structure.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 include/linux/i2c.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 44ad14e..7a1f26e 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -671,6 +671,7 @@ struct i2c_adapter {
 	struct rt_mutex bus_lock;
 	struct rt_mutex mux_lock;
 
+	u32 bus_freq_hz;
 	int timeout;			/* in jiffies */
 	int retries;
 	struct device dev;		/* the adapter device */
-- 
2.9.4

[RFC PATCH 2/2] i2c: at91: provide bus_freq_hz

[Tudor Ambarus]

The clock-frequency property is not mandatory for the i2c buses. If it's
not present in device tree, the buses usually assume that is 100kHZ.
There are i2c clients that need to know the clock frequency in order to
compute their wake token. Spare the clients of making (wrong) assumptions
and provide the bus frequency in adapter.

Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
---
 drivers/i2c/busses/i2c-at91.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
index bfd1fdf..d3cd84e 100644
--- a/drivers/i2c/busses/i2c-at91.c
+++ b/drivers/i2c/busses/i2c-at91.c
@@ -1116,6 +1116,7 @@ static int at91_twi_probe(struct platform_device *pdev)
 	dev->adapter.quirks = &at91_twi_quirks;
 	dev->adapter.dev.parent = dev->dev;
 	dev->adapter.nr = pdev->id;
+	dev->adapter.bus_freq_hz = bus_clk_rate;
 	dev->adapter.timeout = AT91_I2C_TIMEOUT;
 	dev->adapter.dev.of_node = pdev->dev.of_node;
 
-- 
2.9.4

Re: [RFC PATCH 2/2] i2c: at91: provide bus_freq_hz

[Ludovic Desroches]

On Mon, Mar 26, 2018 at 02:19:27PM +0300, Tudor Ambarus wrote:
> The clock-frequency property is not mandatory for the i2c buses. If it's
> not present in device tree, the buses usually assume that is 100kHZ.
> There are i2c clients that need to know the clock frequency in order to
> compute their wake token. Spare the clients of making (wrong) assumptions
> and provide the bus frequency in adapter.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Acked-by: Ludovic Desroches <ludovic.desroches@microchip.com>

> ---
>  drivers/i2c/busses/i2c-at91.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/i2c/busses/i2c-at91.c b/drivers/i2c/busses/i2c-at91.c
> index bfd1fdf..d3cd84e 100644
> --- a/drivers/i2c/busses/i2c-at91.c
> +++ b/drivers/i2c/busses/i2c-at91.c
> @@ -1116,6 +1116,7 @@ static int at91_twi_probe(struct platform_device *pdev)
>  	dev->adapter.quirks = &at91_twi_quirks;
>  	dev->adapter.dev.parent = dev->dev;
>  	dev->adapter.nr = pdev->id;
> +	dev->adapter.bus_freq_hz = bus_clk_rate;
>  	dev->adapter.timeout = AT91_I2C_TIMEOUT;
>  	dev->adapter.dev.of_node = pdev->dev.of_node;
>  
> -- 
> 2.9.4
> 

Re: [RFC PATCH 1/2] i2c: add bus_freq_hz in i2c_adapter

[Tudor Ambarus]

ping

On 03/26/2018 02:19 PM, Tudor Ambarus wrote:
> The clock-frequency property is not mandatory for the i2c buses. If it's
> not present in device tree, the buses usually asume that it is 100kHZ.
> There are i2c clients that need to know the i2c bus frequency in order to
> compute their wake token. Spare the clients of making (wrong) assumptions
> and save the bus frequency in the i2c_adapter structure.
> 
> Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
> ---
>   include/linux/i2c.h | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/include/linux/i2c.h b/include/linux/i2c.h
> index 44ad14e..7a1f26e 100644
> --- a/include/linux/i2c.h
> +++ b/include/linux/i2c.h
> @@ -671,6 +671,7 @@ struct i2c_adapter {
>   	struct rt_mutex bus_lock;
>   	struct rt_mutex mux_lock;
>   
> +	u32 bus_freq_hz;
>   	int timeout;			/* in jiffies */
>   	int retries;
>   	struct device dev;		/* the adapter device */
>