ACPI / PMIC: Add generic intel_soc_pmic_exec_mipi_pmic_seq_element handling

Most PMIC-s use only a single i2c-address, so after verifying the
i2c-address matches, we can simply pass the call to regmap_update_bits.

This commit adds support for this and hooks this up for the xpower AXP288
PMIC by setting the new pmic_i2c_address field.

This fixes the following errors on display on / off on a Jumper Ezpad
mini 3 and an Onda V80 plus tablet, both of which use the AXP288:

intel_soc_pmic_exec_mipi_pmic_seq_element: Not implemented
intel_soc_pmic_exec_mipi_pmic_seq_element: i2c-addr: 0x34 reg-addr ...
[drm:mipi_exec_pmic [i915]] *ERROR* mipi_exec_pmic failed, error: -95

Instead of these errors on both devices we now correctly turn on / off
DLDO3 (through direct register manipulation). On the Onda V80 plus this
fixes an issue with the backlight being brighter around the borders after
an off / on cycle. This should also help to save some power when the
display is off.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190107111556.4510-4-hdegoede@redhat.com

drivers/acpi/pmic/intel_pmic.c

@@ -359,6 +359,15 @@ int intel_soc_pmic_exec_mipi_pmic_seq_element(u16 i2c_address, u32 reg_address,
 		ret = d->exec_mipi_pmic_seq_element(intel_pmic_opregion->regmap,
 						    i2c_address, reg_address,
 						    value, mask);
+	} else if (d->pmic_i2c_address) {
+		if (i2c_address == d->pmic_i2c_address) {
+			ret = regmap_update_bits(intel_pmic_opregion->regmap,
+						 reg_address, mask, value);
+		} else {
+			pr_err("%s: Unexpected i2c-addr: 0x%02x (reg-addr 0x%x value 0x%x mask 0x%x)\n",
+			       __func__, i2c_address, reg_address, value, mask);
+			ret = -ENXIO;
+		}
 	} 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",

drivers/acpi/pmic/intel_pmic.h

@@ -21,6 +21,8 @@ struct intel_pmic_opregion_data {
 	int power_table_count;
 	struct pmic_table *thermal_table;
 	int thermal_table_count;
+	/* For generic exec_mipi_pmic_seq_element handling */
+	int pmic_i2c_address;
 };
 
 int intel_pmic_install_opregion_handler(struct device *dev, acpi_handle handle, struct regmap *regmap, struct intel_pmic_opregion_data *d);

drivers/acpi/pmic/intel_pmic_xpower.c

@@ -240,6 +240,7 @@ static struct intel_pmic_opregion_data intel_xpower_pmic_opregion_data = {
 	.power_table_count = ARRAY_SIZE(power_table),
 	.thermal_table = thermal_table,
 	.thermal_table_count = ARRAY_SIZE(thermal_table),
+	.pmic_i2c_address = 0x34,
 };
 
 static acpi_status intel_xpower_pmic_gpio_handler(u32 function,