[Intel-gfx] [PATCH v3 2/3] ACPI / PMIC: Implement exec_mipi_pmic_seq_element for CHT Whiskey Cove PMIC

[Ville Syrjälä]

On Thu, Dec 13, 2018 at 12:21:35PM +0100, Hans de Goede wrote:
> Implement the exec_mipi_pmic_seq_element callback for the CHT Whiskey Cove
> PMIC.
> 
> On some CHT devices this fixes the LCD panel not lighting up when it was
> not initialized by the GOP, because an external monitor was plugged in and
> the GOP initialized only the external monitor.
> 
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> ---
> Changes in v2:
> -Interpret data passed to the PMIC MIPI elements according to the docs
>  instead of my own reverse engineered interpretation
> Changes in v3:
> -Use hex values for out of range checks
> -Make intel_cht_wc_exec_mipi_pmic_seq_element return errors
> ---
>  drivers/acpi/pmic/intel_pmic_chtwc.c | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/drivers/acpi/pmic/intel_pmic_chtwc.c b/drivers/acpi/pmic/intel_pmic_chtwc.c
> index 078b0448f30a..8ede74e9b89f 100644
> --- a/drivers/acpi/pmic/intel_pmic_chtwc.c
> +++ b/drivers/acpi/pmic/intel_pmic_chtwc.c
> @@ -12,6 +12,7 @@
>  #include <linux/mfd/intel_soc_pmic.h>
>  #include <linux/platform_device.h>
>  #include <linux/regmap.h>
> +#include <asm/unaligned.h>
>  #include "intel_pmic.h"
>  
>  #define CHT_WC_V1P05A_CTRL		0x6e3b
> @@ -231,6 +232,29 @@ static int intel_cht_wc_pmic_update_power(struct regmap *regmap, int reg,
>  	return regmap_update_bits(regmap, reg, bitmask, on ? 1 : 0);
>  }
>  
> +static int intel_cht_wc_exec_mipi_pmic_seq_element(struct regmap *regmap,
> +						   const u8 *data)
> +{
> +	u32 value, mask, reg_address, address;
> +	u16 i2c_client_address;
> +
> +	/* byte 0 aka PMIC Flag is reserved */
> +	i2c_client_address	= get_unaligned_le16(data + 1);
> +	reg_address		= get_unaligned_le32(data + 3);
> +	value			= get_unaligned_le32(data + 7);
> +	mask			= get_unaligned_le32(data + 11);

Upon further reflection maybe it would better to do this decoding in
the i915 code and just pass each parameter to this hook separately?
That way we wouldn't be spreading the vbt details all over the place.

> +
> +	if (i2c_client_address > 0xff || reg_address > 0xff) {
> +		pr_warn("%s warning addresses too big client 0x%x reg 0x%x\n",
> +			__func__, i2c_client_address, reg_address);
> +		return -ERANGE;
> +	}
> +
> +	address = (i2c_client_address << 8) | reg_address;
> +
> +	return regmap_update_bits(regmap, address, mask, value);
> +}
> +
>  /*
>   * The thermal table and ops are empty, we do not support the Thermal opregion
>   * (DPTF) due to lacking documentation.
> @@ -238,6 +262,7 @@ static int intel_cht_wc_pmic_update_power(struct regmap *regmap, int reg,
>  static struct intel_pmic_opregion_data intel_cht_wc_pmic_opregion_data = {
>  	.get_power		= intel_cht_wc_pmic_get_power,
>  	.update_power		= intel_cht_wc_pmic_update_power,
> +	.exec_mipi_pmic_seq_element = intel_cht_wc_exec_mipi_pmic_seq_element,
>  	.power_table		= power_table,
>  	.power_table_count	= ARRAY_SIZE(power_table),
>  };
> -- 
> 2.19.2

-- 
Ville Syrjälä
Intel