[PATCH 2/3 v2] mfd: Allow mapping regulator supplies to MFD device from children

Charles Keepax
2013-10-15T19:22:18Z

Occasionally, it is useful to map supplies from a child device onto the
MFD device. A typical usecase for this would be if the MFD device is
represented as a single node in device tree. All supplies will be
defined in device tree as existing on the MFD device. When a child
depends on frameworks which might have no knowledge of MFD to lookup
supplies on its behalf the supply will not be found.

This patch adds a list of supplies that should be looked up on the
parent rather than the child as part of the mfd_cell structure.

Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
---
drivers/mfd/mfd-core.c | 22 +++++++++++++++++-----
include/linux/mfd/core.h | 6 ++++++
2 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/drivers/mfd/mfd-core.c b/drivers/mfd/mfd-core.c
index f421586..adc8ea3 100644
--- a/drivers/mfd/mfd-core.c
+++ b/drivers/mfd/mfd-core.c
@@ -20,6 +20,7 @@
#include <linux/module.h>
#include <linux/irqdomain.h>
#include <linux/of.h>
+#include <linux/regulator/consumer.h>

static struct device_type mfd_dev_type = {
.name = "mfd_device",
@@ -99,6 +100,13 @@ static int mfd_add_device(struct device *parent, int id,
pdev->dev.dma_mask = parent->dma_mask;
pdev->dev.dma_parms = parent->dma_parms;

+ ret = devm_regulator_bulk_register_supply_alias(
+ &pdev->dev, cell->parent_supplies,
+ parent, cell->parent_supplies,
+ cell->num_parent_supplies);
+ if (ret < 0)
+ goto fail_res;
+
if (parent->of_node && cell->of_compatible) {
for_each_child_of_node(parent->of_node, np) {
if (of_device_is_compatible(np, cell->of_compatible)) {
@@ -112,12 +120,12 @@ static int mfd_add_device(struct device *parent, int id,
ret = platform_device_add_data(pdev,
cell->platform_data, cell->pdata_size);
if (ret)
- goto fail_res;
+ goto fail_alias;
}

ret = mfd_platform_add_cell(pdev, cell);
if (ret)
- goto fail_res;
+ goto fail_alias;

for (r = 0; r < cell->num_resources; r++) {
res[r].name = cell->resources[r].name;
@@ -152,17 +160,17 @@ static int mfd_add_device(struct device *parent, int id,
if (!cell->ignore_resource_conflicts) {
ret = acpi_check_resource_conflict(&res[r]);
if (ret)
- goto fail_res;
+ goto fail_alias;
}
}

ret = platform_device_add_resources(pdev, res, cell->num_resources);
if (ret)
- goto fail_res;
+ goto fail_alias;

ret = platform_device_add(pdev);
if (ret)
- goto fail_res;
+ goto fail_alias;

if (cell->pm_runtime_no_callbacks)
pm_runtime_no_callbacks(&pdev->dev);
@@ -171,6 +179,10 @@ static int mfd_add_device(struct device *parent, int id,

return 0;

+fail_alias:
+ devm_regulator_bulk_unregister_supply_alias(&pdev->dev,
+ cell->parent_supplies,
+ cell->num_parent_supplies);
fail_res:
kfree(res);
fail_device:
diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h
index cebe97e..7314fc4 100644
--- a/include/linux/mfd/core.h
+++ b/include/linux/mfd/core.h
@@ -59,6 +59,12 @@ struct mfd_cell {
* pm_runtime_no_callbacks().
*/
bool pm_runtime_no_callbacks;
+
+ /* A list of regulator supplies that should be mapped to the MFD
+ * device rather than the child device when requested
+ */
+ const char **parent_supplies;
+ int num_parent_supplies;
};

/*
--
1.7.2.5