diff mbox series

[v6,2/5] i2c: core: add api to provide frequency mode strings

Message ID 1617197790-30627-3-git-send-email-yangyicong@hisilicon.com
State New
Headers show
Series Add support for HiSilicon I2C controller | expand

Commit Message

Yicong Yang March 31, 2021, 1:36 p.m. UTC 
Some I2C drivers like Designware and HiSilicon will print the
bus frequency mode information, so add a public one that everyone
can make use of.

Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
---
 include/linux/i2c.h | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

Comments

Wolfram Sang April 6, 2021, 7:54 p.m. UTC | #1 
> diff --git a/include/linux/i2c.h b/include/linux/i2c.h

> index 10bd0b0..7268180 100644

> --- a/include/linux/i2c.h

> +++ b/include/linux/i2c.h

> @@ -47,6 +47,26 @@ typedef int (*i2c_slave_cb_t)(struct i2c_client *client,

>  #define I2C_MAX_HIGH_SPEED_MODE_FREQ	3400000

>  #define I2C_MAX_ULTRA_FAST_MODE_FREQ	5000000

>  

> +static inline const char *i2c_freq_mode_string(u32 bus_freq_hz)

> +{

> +	switch (bus_freq_hz) {

> +	case I2C_MAX_STANDARD_MODE_FREQ:

> +		return "Standard Mode (100 kHz)";

> +	case I2C_MAX_FAST_MODE_FREQ:

> +		return "Fast Mode (400 kHz)";

> +	case I2C_MAX_FAST_MODE_PLUS_FREQ:

> +		return "Fast Mode Plus (1.0 MHz)";

> +	case I2C_MAX_TURBO_MODE_FREQ:

> +		return "Turbo Mode (1.4 MHz)";

> +	case I2C_MAX_HIGH_SPEED_MODE_FREQ:

> +		return "High Speed Mode (3.4 MHz)";

> +	case I2C_MAX_ULTRA_FAST_MODE_FREQ:

> +		return "Ultra Fast Mode (5.0 MHz)";

> +	default:

> +		return "Unknown Mode";

> +	}

> +}


Any reason ehy this is an inline function? My gut feeling says it would
be better added to the core?
Yicong Yang April 7, 2021, 8:29 a.m. UTC | #2 
On 2021/4/7 3:54, Wolfram Sang wrote:
> 

>> diff --git a/include/linux/i2c.h b/include/linux/i2c.h

>> index 10bd0b0..7268180 100644

>> --- a/include/linux/i2c.h

>> +++ b/include/linux/i2c.h

>> @@ -47,6 +47,26 @@ typedef int (*i2c_slave_cb_t)(struct i2c_client *client,

>>  #define I2C_MAX_HIGH_SPEED_MODE_FREQ	3400000

>>  #define I2C_MAX_ULTRA_FAST_MODE_FREQ	5000000

>>  

>> +static inline const char *i2c_freq_mode_string(u32 bus_freq_hz)

>> +{

>> +	switch (bus_freq_hz) {

>> +	case I2C_MAX_STANDARD_MODE_FREQ:

>> +		return "Standard Mode (100 kHz)";

>> +	case I2C_MAX_FAST_MODE_FREQ:

>> +		return "Fast Mode (400 kHz)";

>> +	case I2C_MAX_FAST_MODE_PLUS_FREQ:

>> +		return "Fast Mode Plus (1.0 MHz)";

>> +	case I2C_MAX_TURBO_MODE_FREQ:

>> +		return "Turbo Mode (1.4 MHz)";

>> +	case I2C_MAX_HIGH_SPEED_MODE_FREQ:

>> +		return "High Speed Mode (3.4 MHz)";

>> +	case I2C_MAX_ULTRA_FAST_MODE_FREQ:

>> +		return "Ultra Fast Mode (5.0 MHz)";

>> +	default:

>> +		return "Unknown Mode";

>> +	}

>> +}

> 

> Any reason ehy this is an inline function? My gut feeling says it would

> be better added to the core?

> 


it's not a complicated function so i didn't think it'll make much difference,
so i just put it in the header along with the coresponding macro definitions.
do you want me to move it to the core?

Thanks
Andy Shevchenko April 7, 2021, 10:08 a.m. UTC | #3 
On Wed, Apr 07, 2021 at 04:29:29PM +0800, Yicong Yang wrote:
> On 2021/4/7 3:54, Wolfram Sang wrote:

> > 

> >> diff --git a/include/linux/i2c.h b/include/linux/i2c.h

> >> index 10bd0b0..7268180 100644

> >> --- a/include/linux/i2c.h

> >> +++ b/include/linux/i2c.h

> >> @@ -47,6 +47,26 @@ typedef int (*i2c_slave_cb_t)(struct i2c_client *client,

> >>  #define I2C_MAX_HIGH_SPEED_MODE_FREQ	3400000

> >>  #define I2C_MAX_ULTRA_FAST_MODE_FREQ	5000000

> >>  

> >> +static inline const char *i2c_freq_mode_string(u32 bus_freq_hz)

> >> +{

> >> +	switch (bus_freq_hz) {

> >> +	case I2C_MAX_STANDARD_MODE_FREQ:

> >> +		return "Standard Mode (100 kHz)";

> >> +	case I2C_MAX_FAST_MODE_FREQ:

> >> +		return "Fast Mode (400 kHz)";

> >> +	case I2C_MAX_FAST_MODE_PLUS_FREQ:

> >> +		return "Fast Mode Plus (1.0 MHz)";

> >> +	case I2C_MAX_TURBO_MODE_FREQ:

> >> +		return "Turbo Mode (1.4 MHz)";

> >> +	case I2C_MAX_HIGH_SPEED_MODE_FREQ:

> >> +		return "High Speed Mode (3.4 MHz)";

> >> +	case I2C_MAX_ULTRA_FAST_MODE_FREQ:

> >> +		return "Ultra Fast Mode (5.0 MHz)";

> >> +	default:

> >> +		return "Unknown Mode";

> >> +	}

> >> +}

> > 

> > Any reason ehy this is an inline function? My gut feeling says it would

> > be better added to the core?

> > 

> 

> it's not a complicated function so i didn't think it'll make much difference,

> so i just put it in the header along with the coresponding macro definitions.

> do you want me to move it to the core?


I guess exporting will save few dozens of bytes if the function is used more
than once. (All strings will be duplicated or multiplied in that case)

-- 
With Best Regards,
Andy Shevchenko
Yicong Yang April 7, 2021, 10:24 a.m. UTC | #4 
On 2021/4/7 18:08, Andy Shevchenko wrote:
> On Wed, Apr 07, 2021 at 04:29:29PM +0800, Yicong Yang wrote:

>> On 2021/4/7 3:54, Wolfram Sang wrote:

>>>

>>>> diff --git a/include/linux/i2c.h b/include/linux/i2c.h

>>>> index 10bd0b0..7268180 100644

>>>> --- a/include/linux/i2c.h

>>>> +++ b/include/linux/i2c.h

>>>> @@ -47,6 +47,26 @@ typedef int (*i2c_slave_cb_t)(struct i2c_client *client,

>>>>  #define I2C_MAX_HIGH_SPEED_MODE_FREQ	3400000

>>>>  #define I2C_MAX_ULTRA_FAST_MODE_FREQ	5000000

>>>>  

>>>> +static inline const char *i2c_freq_mode_string(u32 bus_freq_hz)

>>>> +{

>>>> +	switch (bus_freq_hz) {

>>>> +	case I2C_MAX_STANDARD_MODE_FREQ:

>>>> +		return "Standard Mode (100 kHz)";

>>>> +	case I2C_MAX_FAST_MODE_FREQ:

>>>> +		return "Fast Mode (400 kHz)";

>>>> +	case I2C_MAX_FAST_MODE_PLUS_FREQ:

>>>> +		return "Fast Mode Plus (1.0 MHz)";

>>>> +	case I2C_MAX_TURBO_MODE_FREQ:

>>>> +		return "Turbo Mode (1.4 MHz)";

>>>> +	case I2C_MAX_HIGH_SPEED_MODE_FREQ:

>>>> +		return "High Speed Mode (3.4 MHz)";

>>>> +	case I2C_MAX_ULTRA_FAST_MODE_FREQ:

>>>> +		return "Ultra Fast Mode (5.0 MHz)";

>>>> +	default:

>>>> +		return "Unknown Mode";

>>>> +	}

>>>> +}

>>>

>>> Any reason ehy this is an inline function? My gut feeling says it would

>>> be better added to the core?

>>>

>>

>> it's not a complicated function so i didn't think it'll make much difference,

>> so i just put it in the header along with the coresponding macro definitions.

>> do you want me to move it to the core?

> 

> I guess exporting will save few dozens of bytes if the function is used more

> than once. (All strings will be duplicated or multiplied in that case)

> 


yes, that's one concern. since we don't need this to perform fast, an inline
one maybe unnecessary.
Wolfram Sang April 7, 2021, 10:56 p.m. UTC | #5 
> > I guess exporting will save few dozens of bytes if the function is used more

> > than once. (All strings will be duplicated or multiplied in that case)

> > 

> 

> yes, that's one concern. since we don't need this to perform fast, an inline

> one maybe unnecessary.


Exactly. I also don't see an advantage of the function being inline. But
potential disadvantage, even if just small memory overhead. So, I'd
still rather see it as a core function.
diff mbox series

Patch

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 10bd0b0..7268180 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -47,6 +47,26 @@  typedef int (*i2c_slave_cb_t)(struct i2c_client *client,
 #define I2C_MAX_HIGH_SPEED_MODE_FREQ	3400000
 #define I2C_MAX_ULTRA_FAST_MODE_FREQ	5000000
 
+static inline const char *i2c_freq_mode_string(u32 bus_freq_hz)
+{
+	switch (bus_freq_hz) {
+	case I2C_MAX_STANDARD_MODE_FREQ:
+		return "Standard Mode (100 kHz)";
+	case I2C_MAX_FAST_MODE_FREQ:
+		return "Fast Mode (400 kHz)";
+	case I2C_MAX_FAST_MODE_PLUS_FREQ:
+		return "Fast Mode Plus (1.0 MHz)";
+	case I2C_MAX_TURBO_MODE_FREQ:
+		return "Turbo Mode (1.4 MHz)";
+	case I2C_MAX_HIGH_SPEED_MODE_FREQ:
+		return "High Speed Mode (3.4 MHz)";
+	case I2C_MAX_ULTRA_FAST_MODE_FREQ:
+		return "Ultra Fast Mode (5.0 MHz)";
+	default:
+		return "Unknown Mode";
+	}
+}
+
 struct module;
 struct property_entry;