| Message ID | cabb42db7aec59f0b795a16809b0ccfaeddb2679.camel@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 05/18/2018 01:20 PM, Andy Shevchenko wrote: > On Fri, 2018-05-18 at 11:37 +0300, Andy Shevchenko wrote: >> On Fri, 2018-05-18 at 09:48 +0200, Hans de Goede wrote: >> >> >>> Could it be the i2c input clock definition in drivers/mfd/intel- >>> lpss- >>> pci.c >>> is also wrong for Apollo Lake (N3450) ? There are lots of people >>> having >>> various issues with i2c attached touchpads on Apollo Lake devices, >>> this bug: >>> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1728244 >>> >>> Is sort of a collection bug for these. Various models laptops, lots >>> of >>> reporters. Note not sure thie is an i2c-designware issue, but it >>> would >>> be good to double check the input clock on Apollo Lake. >>> >>> I've checked the datasheet and the datasheet mentions 133MHz as >>> "serial input clk" in the lpio_bxt_regs Registers Summary, which is >>> also part of the LPSS, no clk is mentioned in the "Summary of >>> DW_apb_i2c_mem_map_DW_apb_i2c_addr_block1 Registers". >> >> The internal datasheet we have access to mentioned in this case for >> Broxton and Cannonlake together. So, your assumption might be quite >> close to the truth and the issue is inherited from Broxton. >> > Nope. The specification I have mention the I2C input clock in Broxton is fixed 133 MHz but in Cannon Lake it is derived through non-SW visible divider. > Hans, can your reporters try the following patch? Depending on the > result I may send it out ASAP. > > --- a/drivers/mfd/intel-lpss-pci.c > +++ b/drivers/mfd/intel-lpss-pci.c > @@ -120,7 +120,7 @@ static struct property_entry apl_i2c_properties[] = > { > }; > > static const struct intel_lpss_platform_info apl_i2c_info = { > - .clk_rate = 133000000, > + .clk_rate = 216000000, > .properties = apl_i2c_properties, > }; > Nack. The Apollo Lake HW here shows expected I2C bus clock on oscilloscope so it is indeed clocked at 133 MHz.
Hi, On 18-05-18 12:58, Jarkko Nikula wrote: > On 05/18/2018 01:20 PM, Andy Shevchenko wrote: >> On Fri, 2018-05-18 at 11:37 +0300, Andy Shevchenko wrote: >>> On Fri, 2018-05-18 at 09:48 +0200, Hans de Goede wrote: >>> >>> >>>> Could it be the i2c input clock definition in drivers/mfd/intel- >>>> lpss- >>>> pci.c >>>> is also wrong for Apollo Lake (N3450) ? There are lots of people >>>> having >>>> various issues with i2c attached touchpads on Apollo Lake devices, >>>> this bug: >>>> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1728244 >>>> >>>> Is sort of a collection bug for these. Various models laptops, lots >>>> of >>>> reporters. Note not sure thie is an i2c-designware issue, but it >>>> would >>>> be good to double check the input clock on Apollo Lake. >>>> >>>> I've checked the datasheet and the datasheet mentions 133MHz as >>>> "serial input clk" in the lpio_bxt_regs Registers Summary, which is >>>> also part of the LPSS, no clk is mentioned in the "Summary of >>>> DW_apb_i2c_mem_map_DW_apb_i2c_addr_block1 Registers". >>> >>> The internal datasheet we have access to mentioned in this case for >>> Broxton and Cannonlake together. So, your assumption might be quite >>> close to the truth and the issue is inherited from Broxton. >>> >> > Nope. The specification I have mention the I2C input clock in Broxton is fixed 133 MHz but in Cannon Lake it is derived through non-SW visible divider. > >> Hans, can your reporters try the following patch? Depending on the >> result I may send it out ASAP. >> >> --- a/drivers/mfd/intel-lpss-pci.c >> +++ b/drivers/mfd/intel-lpss-pci.c >> @@ -120,7 +120,7 @@ static struct property_entry apl_i2c_properties[] = >> { >> }; >> static const struct intel_lpss_platform_info apl_i2c_info = { >> - .clk_rate = 133000000, >> + .clk_rate = 216000000, >> .properties = apl_i2c_properties, >> }; >> > Nack. The Apollo Lake HW here shows expected I2C bus clock on oscilloscope so it is indeed clocked at 133 MHz. Ok, thank you for checking this. Regards, Hans -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
--- a/drivers/mfd/intel-lpss-pci.c +++ b/drivers/mfd/intel-lpss-pci.c @@ -120,7 +120,7 @@ static struct property_entry apl_i2c_properties[] = { }; static const struct intel_lpss_platform_info apl_i2c_info = { - .clk_rate = 133000000, + .clk_rate = 216000000, .properties = apl_i2c_properties, };