[PATCH v3 1/3] ACPI / PMIC: Add support for executing PMIC MIPI sequence elements

[Jani Nikula]

On Thu, 13 Dec 2018, Hans de Goede <hdegoede at redhat.com> 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.
>
> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> ---
> Changes in v3:
> -Add kerneldoc for intel_soc_pmic_exec_mipi_pmic_seq_element
> -Make intel_soc_pmic_exec_mipi_pmic_seq_element return errors
> ---
>  drivers/acpi/pmic/intel_pmic.c     | 42 ++++++++++++++++++++++++++++++
>  drivers/acpi/pmic/intel_pmic.h     |  1 +
>  include/linux/mfd/intel_soc_pmic.h |  2 ++
>  3 files changed, 45 insertions(+)
>
> diff --git a/drivers/acpi/pmic/intel_pmic.c b/drivers/acpi/pmic/intel_pmic.c
> index ca18e0d23df9..61f99735fd41 100644
> --- a/drivers/acpi/pmic/intel_pmic.c
> +++ b/drivers/acpi/pmic/intel_pmic.c
> @@ -15,6 +15,7 @@
>  
>  #include <linux/export.h>
>  #include <linux/acpi.h>
> +#include <linux/mfd/intel_soc_pmic.h>
>  #include <linux/regmap.h>
>  #include <acpi/acpi_lpat.h>
>  #include "intel_pmic.h"
> @@ -36,6 +37,8 @@ struct intel_pmic_opregion {
>  	struct intel_pmic_regs_handler_ctx ctx;
>  };
>  
> +static struct intel_pmic_opregion *intel_pmic_opregion;
> +
>  static int pmic_get_reg_bit(int address, struct pmic_table *table,
>  			    int count, int *reg, int *bit)
>  {
> @@ -304,6 +307,7 @@ int intel_pmic_install_opregion_handler(struct device *dev, acpi_handle handle,
>  	}
>  
>  	opregion->data = d;
> +	intel_pmic_opregion = opregion;
>  	return 0;
>  
>  out_remove_thermal_handler:
> @@ -319,3 +323,41 @@ int intel_pmic_install_opregion_handler(struct device *dev, acpi_handle handle,
>  	return ret;
>  }
>  EXPORT_SYMBOL_GPL(intel_pmic_install_opregion_handler);
> +
> +/**
> + * intel_soc_pmic_exec_mipi_pmic_seq_element - Execute PMIC MIPI sequence
> + * @data: Pointer to *15* byte PMIC MIPI sequence element
> + *
> + * 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(const u8 *data)
> +{
> +	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;
> +	if (!d->exec_mipi_pmic_seq_element) {
> +		pr_warn("%s: Not implemented\n", __func__);
> +		pr_warn("%s: Data: %15ph\n", __func__, data);
> +		return -EOPNOTSUPP;
> +	}
> +
> +	mutex_lock(&intel_pmic_opregion->lock);
> +	ret = d->exec_mipi_pmic_seq_element(intel_pmic_opregion->regmap, data);
> +	mutex_unlock(&intel_pmic_opregion->lock);
> +
> +	return ret;
> +}
> +EXPORT_SYMBOL_GPL(intel_soc_pmic_exec_mipi_pmic_seq_element);
> diff --git a/drivers/acpi/pmic/intel_pmic.h b/drivers/acpi/pmic/intel_pmic.h
> index 095afc96952e..1cc5e69af0c3 100644
> --- a/drivers/acpi/pmic/intel_pmic.h
> +++ b/drivers/acpi/pmic/intel_pmic.h
> @@ -15,6 +15,7 @@ struct intel_pmic_opregion_data {
>  	int (*update_aux)(struct regmap *r, int reg, int raw_temp);
>  	int (*get_policy)(struct regmap *r, int reg, int bit, u64 *value);
>  	int (*update_policy)(struct regmap *r, int reg, int bit, int enable);
> +	int (*exec_mipi_pmic_seq_element)(struct regmap *r, const u8 *data);
>  	struct pmic_table *power_table;
>  	int power_table_count;
>  	struct pmic_table *thermal_table;
> diff --git a/include/linux/mfd/intel_soc_pmic.h b/include/linux/mfd/intel_soc_pmic.h
> index ed1dfba5e5f9..71a8607a0a8c 100644
> --- a/include/linux/mfd/intel_soc_pmic.h
> +++ b/include/linux/mfd/intel_soc_pmic.h
> @@ -26,4 +26,6 @@ struct intel_soc_pmic {
>  	struct device *dev;
>  };
>  
> +int intel_soc_pmic_exec_mipi_pmic_seq_element(const u8 *data);

Add a static inline dummy implementation with error return for
CONFIG_PMIC_OPREGION=n? Maybe even with pr_err or pr_warn or something?

BR,
Jani.

> +
>  #endif	/* __INTEL_SOC_PMIC_H__ */

-- 
Jani Nikula, Intel Open Source Graphics Center