Re: [PATCH] mfd: intel-lpss: Add default I2C device properties for Apollo Lake

[Lee Jones <lee.jones@linaro.org>]

On Mon, 12 Sep 2016, Jarkko Nikula wrote:

> Default I2C device properties for Intel Broxton, especially SDA hold time
> may not be enough on Intel Apollo Lake. These properties are used in case
> we don't get timing parameters from ACPI.
> 
> The default SDA hold time for Broxton may fail with arbitration lost errors
> on Apollo Lake:
> 
>   i2c_designware i2c_designware.1: i2c_dw_handle_tx_abort: lost arbitration
> 
> Fix this by using different default device properties on Apollo Lake than
> Broxton.
> 
> Reported-by: Paul Liu <paul.liu@canonical.com>
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=156181
> Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
> ---
> Hi Paul. This is the same patch I shared you offline but rebased on top
> of mfd.git, essentially on top of commit 19063e1b0aaa ("mfd: lpss: Add
> Intel Kaby Lake PCH-H PCI IDs") and commit log a little bit edited.
> ---
>  drivers/mfd/intel-lpss-acpi.c | 14 +++++++++++++-
>  drivers/mfd/intel-lpss-pci.c  | 28 ++++++++++++++++++++--------
>  2 files changed, 33 insertions(+), 9 deletions(-)

Patch looks okay.

Would like Paul's Acked-by or Tested-by to complete the loop.

Acked-for-MFD-by: Lee Jones <lee.jones@linaro.org>

> diff --git a/drivers/mfd/intel-lpss-acpi.c b/drivers/mfd/intel-lpss-acpi.c
> index 7ddc4a9563ea..6bf8d643d942 100644
> --- a/drivers/mfd/intel-lpss-acpi.c
> +++ b/drivers/mfd/intel-lpss-acpi.c
> @@ -52,6 +52,18 @@ static const struct intel_lpss_platform_info bxt_i2c_info = {
>  	.properties = bxt_i2c_properties,
>  };
>  
> +static struct property_entry apl_i2c_properties[] = {
> +	PROPERTY_ENTRY_U32("i2c-sda-hold-time-ns", 207),
> +	PROPERTY_ENTRY_U32("i2c-sda-falling-time-ns", 171),
> +	PROPERTY_ENTRY_U32("i2c-scl-falling-time-ns", 208),
> +	{ },
> +};
> +
> +static const struct intel_lpss_platform_info apl_i2c_info = {
> +	.clk_rate = 133000000,
> +	.properties = apl_i2c_properties,
> +};
> +
>  static const struct acpi_device_id intel_lpss_acpi_ids[] = {
>  	/* SPT */
>  	{ "INT3446", (kernel_ulong_t)&spt_i2c_info },
> @@ -61,7 +73,7 @@ static const struct acpi_device_id intel_lpss_acpi_ids[] = {
>  	{ "80860ABC", (kernel_ulong_t)&bxt_info },
>  	{ "80860AC2", (kernel_ulong_t)&bxt_info },
>  	/* APL */
> -	{ "80865AAC", (kernel_ulong_t)&bxt_i2c_info },
> +	{ "80865AAC", (kernel_ulong_t)&apl_i2c_info },
>  	{ "80865ABC", (kernel_ulong_t)&bxt_info },
>  	{ "80865AC2", (kernel_ulong_t)&bxt_info },
>  	{ }
> diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c
> index d19569a0f2f9..3228fd182a99 100644
> --- a/drivers/mfd/intel-lpss-pci.c
> +++ b/drivers/mfd/intel-lpss-pci.c
> @@ -111,6 +111,18 @@ static const struct intel_lpss_platform_info bxt_i2c_info = {
>  	.properties = bxt_i2c_properties,
>  };
>  
> +static struct property_entry apl_i2c_properties[] = {
> +	PROPERTY_ENTRY_U32("i2c-sda-hold-time-ns", 207),
> +	PROPERTY_ENTRY_U32("i2c-sda-falling-time-ns", 171),
> +	PROPERTY_ENTRY_U32("i2c-scl-falling-time-ns", 208),
> +	{ },
> +};
> +
> +static const struct intel_lpss_platform_info apl_i2c_info = {
> +	.clk_rate = 133000000,
> +	.properties = apl_i2c_properties,
> +};
> +
>  static const struct intel_lpss_platform_info kbl_info = {
>  	.clk_rate = 120000000,
>  };
> @@ -159,14 +171,14 @@ static const struct pci_device_id intel_lpss_pci_ids[] = {
>  	{ PCI_VDEVICE(INTEL, 0x1aee), (kernel_ulong_t)&bxt_uart_info },
>  
>  	/* APL */
> -	{ PCI_VDEVICE(INTEL, 0x5aac), (kernel_ulong_t)&bxt_i2c_info },
> -	{ PCI_VDEVICE(INTEL, 0x5aae), (kernel_ulong_t)&bxt_i2c_info },
> -	{ PCI_VDEVICE(INTEL, 0x5ab0), (kernel_ulong_t)&bxt_i2c_info },
> -	{ PCI_VDEVICE(INTEL, 0x5ab2), (kernel_ulong_t)&bxt_i2c_info },
> -	{ PCI_VDEVICE(INTEL, 0x5ab4), (kernel_ulong_t)&bxt_i2c_info },
> -	{ PCI_VDEVICE(INTEL, 0x5ab6), (kernel_ulong_t)&bxt_i2c_info },
> -	{ PCI_VDEVICE(INTEL, 0x5ab8), (kernel_ulong_t)&bxt_i2c_info },
> -	{ PCI_VDEVICE(INTEL, 0x5aba), (kernel_ulong_t)&bxt_i2c_info },
> +	{ PCI_VDEVICE(INTEL, 0x5aac), (kernel_ulong_t)&apl_i2c_info },
> +	{ PCI_VDEVICE(INTEL, 0x5aae), (kernel_ulong_t)&apl_i2c_info },
> +	{ PCI_VDEVICE(INTEL, 0x5ab0), (kernel_ulong_t)&apl_i2c_info },
> +	{ PCI_VDEVICE(INTEL, 0x5ab2), (kernel_ulong_t)&apl_i2c_info },
> +	{ PCI_VDEVICE(INTEL, 0x5ab4), (kernel_ulong_t)&apl_i2c_info },
> +	{ PCI_VDEVICE(INTEL, 0x5ab6), (kernel_ulong_t)&apl_i2c_info },
> +	{ PCI_VDEVICE(INTEL, 0x5ab8), (kernel_ulong_t)&apl_i2c_info },
> +	{ PCI_VDEVICE(INTEL, 0x5aba), (kernel_ulong_t)&apl_i2c_info },
>  	{ PCI_VDEVICE(INTEL, 0x5abc), (kernel_ulong_t)&bxt_uart_info },
>  	{ PCI_VDEVICE(INTEL, 0x5abe), (kernel_ulong_t)&bxt_uart_info },
>  	{ PCI_VDEVICE(INTEL, 0x5ac0), (kernel_ulong_t)&bxt_uart_info },

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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