[Intel-gfx] [PATCH v6 1/4] ACPI / PMIC: Add support for executing PMIC MIPI sequence elements

[Hans de Goede]

Hi,

On 07-01-19 16:35, Andy Shevchenko wrote:
> On Mon, Jan 07, 2019 at 12:15:53PM +0100, Hans de Goede wrote:
>> DSI LCD panels describe an initialization sequence in the Video BIOS
>> Tables using so called MIPI sequences. One possible element in these
>> sequences is a PMIC specific element of 15 bytes.
>>
>> Although this is not really an ACPI opregion, the ACPI opregion code is the
>> closest thing we have. We need to have support for these PMIC specific MIPI
>> sequence elements somwhere. Since we already instantiate a special platform
>> device for Intel PMICs for the ACPI PMIC OpRegion handler to bind to,
>> with PMIC specific implementations of the OpRegion, the handling of MIPI
>> sequence PMIC elements fits very well in the ACPI PMIC OpRegion code.
>>
>> This commit adds a new intel_soc_pmic_exec_mipi_pmic_seq_element()
>> function, which is to be backed by a PMIC specific
>> exec_mipi_pmic_seq_element callback. This function will be called by the
>> i915 code to execture MIPI sequence PMIC elements.
> 
>> +/**
>> + * intel_soc_pmic_exec_mipi_pmic_seq_element - Execute PMIC MIPI sequence
> 
> I wonder if we need pmic duplication in the name.

Mipi sequences can do a bunch of things, talk to the panel over
the MIPI bus, set GPIOs, read-modify-write PMIC registers, etc.

This function can only execute the PMIC bits, not the rest,
so the second pmic is there to indiciate we are executing
a PMIC MIPI sequence and not e.g. a GPIO one. So I believe that
keeping this as is is best.

Regards,

Hans


>> + * @i2c_address:  I2C client address for the PMIC
>> + * @reg_address:  PMIC register address
>> + * @value:        New value for the register bits to change
>> + * @mask:         Mask indicating which register bits to change
>> + *
>> + * DSI LCD panels describe an initialization sequence in the i915 VBT (Video
>> + * BIOS Tables) using so called MIPI sequences. One possible element in these
>> + * sequences is a PMIC specific element of 15 bytes.
>> + *
>> + * This function executes these PMIC specific elements sending the embedded
>> + * commands to the PMIC.
>> + *
>> + * Return 0 on success, < 0 on failure.
>> + */
>> +int intel_soc_pmic_exec_mipi_pmic_seq_element(u16 i2c_address, u32 reg_address,
>> +					      u32 value, u32 mask)
>> +{
>> +	struct intel_pmic_opregion_data *d;
>> +	int ret;
>> +
>> +	if (!intel_pmic_opregion) {
>> +		pr_warn("%s: No PMIC registered\n", __func__);
>> +		return -ENXIO;
>> +	}
>> +
>> +	d = intel_pmic_opregion->data;
>> +
>> +	mutex_lock(&intel_pmic_opregion->lock);
>> +
>> +	if (d->exec_mipi_pmic_seq_element) {
> 
>> +		ret = d->exec_mipi_pmic_seq_element(intel_pmic_opregion->regmap,
>> +						    i2c_address, reg_address,
>> +						    value, mask);
> 
> Here it's not quite a dup, but it's implied by the name of structure...
> 
>> +	} else {
>> +		pr_warn("%s: Not implemented\n", __func__);
>> +		pr_warn("%s: i2c-addr: 0x%x reg-addr 0x%x value 0x%x mask 0x%x\n",
>> +			__func__, i2c_address, reg_address, value, mask);
>> +		ret = -EOPNOTSUPP;
>> +	}
>> +
>> +	mutex_unlock(&intel_pmic_opregion->lock);
>> +
>> +	return ret;
>> +}
>